DNA – Douglas Noel Adams and Deoxyribonucleic Acid

I’ve recently had a kind of brainworm I had to get down on paper, or rather on screen as it is nowadays, though it needn’t be. It focusses on ‘The Hitch-Hiker’s Guide To The Galaxy’ and I have of course spent way too much time concentrating on this to the detriment of the work itself, but I can’t resist it. On this occasion though, it yielded fruit, almost literally in fact, and turned out to culminate in something which was a lot less ridiculous than I initially thought. The problem was that despite it not being particularly pointful, I couldn’t get it out of my head.

The ultimate question, so to speak, is this:

How many species of organism could be rescued from Earth after it gets demolished by the Vogons?

This thought originated from the scene in Fit The First where Ford and Arthur are hiding on the Vogon spaceship, having just beamed aboard, and after a suitable pause, Ford tells Arthur, “I brought some peanuts.” When I heard this line, I felt a sense of poignancy that not only had the world just ended, but apparently the only other species of Earth life than humans which persisted, the peanut, would shortly itself be destroyed by Arthur’s digestive juices, and then that would be it: nothing would remain other than Arthur, as far as the listener knows at the time. Further consideration, and further listening, would demonstrate that this was not in fact so. And so begins the highly elaborate glass bead game.

There are, considering the entire trilogy of five books, several categories of life originating on this planet involved. It breaks down thus, and I am going to number the categories because they are quite enlightening:

1. Trillian and Arthur themselves. Humans survived the destruction of the planet.
2. Organisms whose DNA or other biological traces are on or in Arthur, or stand a chance of being associated with him.
3. The same issue considering Trillian. It may seem arbitrary to cleave the two humans in this way, but it turns out to be anything but. I’ll come back to this.
4. Other organisms who left Earth before or during its destruction, either canonically or plausibly without evoking the canon.
5. Earth organisms who canonically sprung into being due to the operation of the Infinite Improbability Drive.
6. Organisms accidentally removed in other ways.
7. Organisms mentioned which appear to be from Earth but in fact are not.

I’m going to consider these in reverse order.

Organisms Only Apparently From Earth

Items are mentioned here and there whose origin appears to be terrestrial but is apparently not. For instance, Ford asks the Vogon guard whether the appeal of his job is wearing rubber. Rubber could be considered as originating only from a specific tree originating in Brazil, Hevea brasiliensis, the rubber tree. However, two facts argue against this. One is that latex from other plants can and has been used to make rubber, for instance dandelions. The other is that synthetic rubbers exist and the word could be used less strictly, and may well be. For instance, there is silicone rubber. Hence rubber itself probably shouldn’t be taken to indicate that there are rubber trees of that species elsewhere in the Universe.

This is in fact kind of acknowledged in the books, with the existence of jynnan tonix and ouisghiansodas. Many civilisations throughout the Galaxy have a drink called something like “gin and tonic”, although beyond the name they don’t resemble each other, and it also turns out that there’s another similar coincidence, undiscovered and unacknowledged, in the form of “whisky and soda”. Given this, it’s possible that the various items referred to are not identical to an Earth reader’s concept of those things. They may in fact be almost but not entirely like them. The obvious answer here is tea, as produced by the Nutrimat Machine. It isn’t clear where this originates. Tea is available from the local megamart in a variety of easy to swallow capsules, and the initial creation of the Infinite Improbability Drive required a cup of really hot tea. It isn’t clear why, because hot water might be thought to suffice. Arthur is also made the best tea he’s ever tasted at one point on the Heart Of Gold. Hence for some reason, tea appears to exist, or to have existed in the past, elsewhere in the Universe. However, like rubber the word “tea” has a more generic meaning, referring to any vegetable matter infused in hot water, such as chamomile tea or rooibosch. Even so, Arthur clearly perceives the tea as tea. Two things may have happened here. Either literal Camellia sinensis exists on other worlds or it was obtained from Earth. There is a third possibility which will be considered later.

One fruit is mentioned at least thrice. The Pan-Galactic Gargle Blaster is described as having one’s brains smashed out by a slice of lemon wrapped around a large gold brick. When Ford and Arthur arrive on the ‘B’ Ark, the security guard offers them a lemon with their jynnan tonix. Finally, on Brontitall, the starship is delayed nine hundred years while waiting for lemon-soaked paper napkins. This is quite a striking recurrence. It’s possible that the lemon arrived with the Golgafrinchams on the ‘B’ Ark, but perhaps interestingly the scent of lemon is quite widely distributed through plants on this planet, such as lemon grass and lemon verbena. It’s one of two enantiomers of limonene, the other being the scent of oranges. There are also other lemon-flavoured organisms, such as black ants. The presence of citric acid in an organic life form would probably not be unusual. For whatever reason, something lemony is out there among the stars. Perhaps even a lemon.

Potatoes seem to be another such organism. These are very ancient. The Silastic Armourfiends were ordered to punch bags of potatoes to vent their aggression many millions of years before the manufacture of Earth and therefore the appearance of potatoes as we know them. Again, this could be a generic reference to tuberous root vegetables. Even on Earth we have starchy root crops similar to potatoes, such as sweet potatoes.

A further species, possibly several, crops up in Deep Thought’s original deduction of a recipe for rice pudding. This includes rice, milk, cream and cinnamon in the TV version. The existence of rice is not controversial. It means that rice pudding existed at that point in time. To digress slightly, it’s difficult to know how to refer to deep time in H2G2 because in its universe Earth didn’t exist before a few million years ago, so it’s not sensible to use the conjectured geological time periods such as “Jurassic” before the planet was built. The only real epochs are the Pliocene, Pleistocene and Holocene, the only real era is the Cenozoic, and not all of that. The question regarding Deep Thought here, though, is whether it anticipated the existence of rice pudding or deduced its current presence in the Universe. If it did the former, there’s an issue with why it couldn’t simply use its anticipation of the future course of Earth history to give the mice the Ultimate Question, so it makes more sense to see it as already in existence. The existence of milk in this recipe is pretty unproblematic, as milk is just what we call opaque white potable liquids such as coconut milk, and sometimes even impotable ones such as dandelion milk. Cinnamon, however, is highly specific.

It’s possible to extract a principle from this: there are generic items in the wider Universe which have surprisingly specific resemblances to familiar terrestrial ones. Out there in the Galaxy there is milk and rubber, perhaps unsurprisingly, but also tea, potatoes, lemon and even cinnamon. Incidentally, I have to get this out of my head: the spice Melange from Frank Herbert’s ‘Dune’ series has similarities to cinnamon according to the now-banned Dune Encyclopedia, so it isn’t just H2G2 which anticipates the existence of interstellar cinnamon (brand new sentence there). There are two other aspects to this. In an infinite Universe, everything is possible according to the Guide, so for example the Babel fish and ratchet screwdriver trees exist, as do sentient mattresses. Just on the last issue, it is kind of true even on Earth that living mattresses and lilos are possible as they did before the evolution of life as we know it since the Cambrian. This means that every species found on Earth does in fact exist somewhere else in the Universe, and in fact that a carbon copy of Earth exists which was not built by the Magratheans. Maybe we’re on that Earth and Arthur Dent’s an alien. The other aspect is that Deep Thought could have designed Earth as a microcosm of the wider Galaxy with organisms resembling those from elsewhere, so it isn’t that there are coincidentally or by convergence life forms elsewhere so much as that they were deliberately put here.

Organisms Accidentally Removed in Various Ways

The main mechanism here is teasers, or as we call them, little green men. These are occupants of interstellar craft who visit Earth and other planets and pretend to be stereotypical aliens. They are presumably also abductors, creators of crop circles, and interfere with cattle. I’m going to assume that the most contact they have with organisms on Earth is in the form of trampling on crop circles, which I also assume they make in the same way as the hoaxers do. Incidentally, although crop circles and UFOs were not widely associated by the public until something like 1990, the association did exist back in the ’70s but was only made in flying saucer enthusiast circles, so to speak. This is of course leading up to the “fact” that teasers take wheat pollen with them when they leave – Triticum aestivum. There’s another aspect to their visit which I will consider under another heading as it’s best considered with Trillian and particularly Arthur.

When the Earth explodes, various particularly tough organisms such as extremophiles might survive in the ensuing cloud of débris. Tardigrades are the obvious example, as they can survive dormant in space, possibly for years. There may even be tardigrades on Mars, and there definitely are on Cynthia (“the Moon”). Another category of organisms this clearly applies to is certain archaeans. Archaeans are microörganisms once confused with bacteria, many of which can survive in extreme conditions such as hot springs. These could possibly survive too, again perhaps in a dormant state.

Zaphod Beeblebrox also visited Earth and took one organism, Trillian, with him deliberately, but probably also took others accidentally. I’ll go into this in greater depth when I consider Trillian.

Finally, Arthur finds an unexpected bottle of retsina:

Vitis vinifera – grape. Used in the retsina Arthur finds on Agrajag’s planet.

Pinus halepensis – Aleppo pine, whose resin is an ingredient of retsina.

Saccharomyces cerevisiae – Brewer’s yeast, found in the retsina.

Infinite Improbability Drive Creations

Several organisms are created when the Infinite Improbability Drive is operated. There are very obvious examples, but I’ll deal with them in order of the timelike curve described by the Heart Of Gold.

The first time the drive is operated, it causes two hundred and thirty-nine thousand fried eggs to appear on the planet Poghril, where all but one person had just died of starvation. This seems at first to imply that it brought Gallus domesticus into existence, but actually it doesn’t. Eggs are a common means of reproduction found throughout the metazoan clade, such as with slugs, spiders and birds. These particular eggs must resemble hen’s to some extent because they seem to contain albumen and yolks and are altered by frying in a familiar way. At no point did they have shells, incidentally, as they were yanked into being without them. They are also high in cholesterol. Even so, I don’t believe these have to be hen’s eggs.

Now for the two most prominent incidents. When Ford and Arthur are rescued, they meet several species of animal on the Heart Of Gold and Ford turns into a penguin. I’m not sure whether to count that because he’s only temporarily transformed. There’s also a five-headed person crawling up a wall, but there are no such organisms on Earth. What there is, however, is an infinite number of monkeys, apparently capuchins. It isn’t clear what happens to any of these species but they don’t seem to be in evidence once normality is restored. That’s not true, though, of the sperm whale and the bowl of petunias. This next bit, therefore, is easy: Petunia and Physeter catadon. There’s even flesh strewn around on Magrathea afterwards. Although it’s straightforward that these species are brought into existence, it’s not so clear that they were alone. The sperm whale could, for all we know, be encrusted with barnacles and contain typical gut flora for a sperm whale along with parasites such as a tapeworm, but the simplest assumption is that the sperm whale is isolated. It’s also fair to question which organisms if any co-occurred with the Petunia, since it is in a bowl and therefore potted in some material. However, again we don’t know that this is so.

Just a side-issue on this: there was at one point going to be a goat on the Heart of Gold after Arthur rescued everyone from the missiles, but this was not pursued. On other occasions, there was a fossilised towel, but nothing is recorded to have happened in that respect when it was operated to escape from the Vogons or visit the Man In The Shack.

There is a flaw in how I’ve considered this. In fact, any terrestrial species could be conjured into existence by the Infinite Improbability Drive, but not in the narrative of the actual stories.

Trillian

Trillian is the most interesting aspect of this entire issue, and in fact she’s why I decided this wasn’t just a frivolous mind game. There is a markèd contrast between Arthur’s and Trillian’s biomes due to the circumstances of their departure and gender, which could in any case be linked.

Trillian was at a party six months before Earth’s destruction. She was surrounded by various alcoholic beverages and snacks. This contributes to her status as a goldmine of genomes, as does her gender presentation. Unlike Arthur she’s likely to have cosmetics, scent and jewellery, as well as residues of toiletries. She was being chatted up by Arthur, then Zaphod, as “Phil”, came along and, well, abducted her right out of that environment, which was not the moribund ecosystem surrounding Arthur as it was being destroyed, but a still-thriving habitat. Many organisms are likely to be held in common between them such as Candida albicans, which is found in the human gut, and in fact many of the microörganisms in their digestive tracts, lungs and body surfaces. Both have, for example, follicle mites – Demodex follicularum. They may also have pathogens, such as rhinovirus, and at a pinch even the likes of fleas and head lice, though probably not. Both have Mentha x piperita – peppermint – in their mouths, or possibly spearmint, from toothpaste.

Here’s a breakdown of what she might distinctively have on her and why:

From cocktails:

Cinchona pubescens – quinine, in bitter lemon.

Juniperus communis – juniper, in gin.

Olea europaea – olive, on cocktail sticks. This is, however, also mentioned in connection with Pan-Galactic Gargle Blasters, so it doesn’t count as distinctively terrestrial.

Prunus avium – cherry, also on cocktail stick.

Curcuma longa – cucumber. This is a long shot but not only might this occur in a cocktail but also in a cucumber sandwich. That also means:

Lepidum sativum – cress.

Sinapis alba – white mustard.

(Mustard and cress sandwiches)

Possibly an Abies species for the cocktail stick, but more likely to be Pinus, which was already in the retsina.

Artemisia absinthium – wormwood, if they had absinthe.

Gallus domesticus – hen, if there was advocaat (eggs).

Vanilla planifolia – vanilla orchid, same source.

Citrus aurantium – orange.

Pyrus malus – apple.

Angostura trifoliata – if they had genuine angostura bitters.

Solanum lycopersicum – tomato.

There would also have been snacks, which might allow various nut species to be recovered, such as Anacardium officinale (cashews), Prunus amygdalus (almond) and others. There could also be other things such as trail mix, pork scratchings or Bombay mix, but it would rely on Trillian actually eating it, and having the drinks.

Canapes might contain:

Salmo salar – salmon

Thunnus tynnus – Atlantic bluefin tuna

Allium sativa – garlic

Again, she’d have to eat or at least touch these. Both these categories are very uncertain, and in fact I can add a couple of quite likely ones:

Ananas comosus – pineapple. There are pretty sure to be pineapple cubes on sticks at this party.

Prawn cocktail – it isn’t clear to me which species of decapod is most popular as food.

Much of the above is culturally and historically specific. Wealthier people would have different food available. Trillian is not wealthy, but on the dole, although she may have had social capital from university days or others. Later on, something like sambuca might have become available, meaning licorice, possibly elder (Sambucus nigra). There is a positive wealth of possible organisms here, but also a high degree of uncertainty.

Cosmetics: Many cosmetics are mineral-based. Their ingredients also change over time, trending at the moment towards plant sources.

Lipstick:

Ricinus communis – Castor oil plant.

Theobroma cacao – cacao. Cocoa butter.

Simmondsia chinensis – Jojoba (also possibly in shampoo and conditioner).

Copernica conifera – Carnauba wax. Could also be on lemon rind.

Dactylopius coccus – cochineal insect. Could also be present in food.

Kerria lacca – lac bug. Possibly in makeup or on lemon rind, might also be on nail varnish.

These last two are likely to be less common today.

Eye shadow: exclusively mineral ingredients.

Mascara: big overlap with lipstick.

Foundation: palmitic acid, which remarkably at this stage (1978) could have been from sperm whale again!

Various glycerol-based lipids from a variety of different sources.

Primer: again remarkably, this could in theory be a source of Thea sinensis or Vitis, but I reckon that’s too sophisticated for the ’70s. Another change.

Blusher:

Cetorhinus maximus – basking shark, source of squalene. Could be a couple of other species. Nowadays this is not from animals, but back then it was. There are other species of shark this could be from.

Shampoo:

Cocos nucifera – coconut palm. TBH, this is probably going to be in something on the above lists anyway.

Elaeis guineensis – oil palm. This doesn’t really belong here but there will be palm oil in something.

Conditioner:

Sorbitol occurs naturally in various fruits.

Perfume and scent ingredients derived from various plants, e.g.

Lavandula angustifolia – lavender

Rosmarinus officinalis – rosemary

Rosa sp – there are so many species of rose it’s ridiculous, so I’m not going to narrow it down further than that.

Jasminum officinale – jasmine.

Pogostemon cablin – patchouli (less likely).

It’s uncertain whether these are just various compounds from the relevant organisms or if their actual genomes would be available. It’s also notable that Trillian has a less detailed back story than Arthur, and some of the uncertainty may result from that. This, sadly, probably arises from Douglas Adams’s sexism. His female characters generally seem to be less filled-out than his male ones. Most of his cybernetic characters are also male, with the exception of the Nutrimatic machine. The type of character Trillian has been made to become is, to be fair, not enormously stereotypical because she’s an astrophysicist, but her presentation is typically feminine, hence the massive biological accoutrements. This could be flipped: why isn’t Arthur expected to make this effort? It’s still interesting that if you remove an average woman from 1970s Islington from Earth, you sample a lot more of the planet’s biosphere with her than if you remove an average man from the rural West Country, even though she’s in an urban environment and he’s in a rural one.

Arthur’s turn. Arthur is a six-foot tall ape descendant (nowadays he’s seen as an ape) who works in local radio, and is of course a man. Here’s a list of what he has on or in him at the end of the world:

Felis cattus – domestic cat. When Arthur arrives back on Earth, there is a dead cat in his house, so he may have had a cat. Some fur may exist on his dressing gown. In fact it almost certainly does, and also aerosols from the cat licking her fur. 

At this point I should probably mention an organism of ‘Trainspotting’ fame: Toxoplasma gondii. Arthur may well actually be subclinically infected by Toxoplasma, as many people associated with cats are.

Canis familiaris – dog. As Arthur is about to be thrown off the Vogon spaceship, he says he was planning to “brush the dog”, so there may also be dog hairs on his dressing gown. Also, possibly Know-Nothing may have done the same, though this is less likely. In case you don’t know, Know-Nothing is the pub dog in Cottington, Arthur’s village.

Right at the start of the narrative portion of the story, Arthur’s morning routine is described.

Bos taurus – cattle. Arthur makes himself a cup of coffee just before he notices the bulldozers outside. The milk he puts in it probably has cow DNA in it.

Coffea robusta – coffee. Since it’s the ’80s, Arthur probably uses instant coffee, hence robusta rather than arabica.

Toothpaste occurs around this stage. There’s also shaving foam, which may contain Gossypium among other ingredients, and there might even be aftershave although this isn’t mentioned.

Humulus lupulus – hops in the six pints of beer Ford buys Arthur at lunchtime.

Hordeum vulgare – barley used to make the beer.

Saccharomyces cerevisiae – the yeast fermenting the beer and the retsina on Agrajag’s planet, which I’ve mentioned.

Arachis hypogaea – peanuts. “I brought some peanuts” – Ford’s comment which started this whole futile enterprise.

Musca domestica – house fly. Arthur swats flies on prehistoric Earth, possibly not that species but at least one species of fly. This is also Agrajag.

Oryctolagus cuniculus – the rabbit Arthur killed to make his bag out of. Also Agrajag.

Ovis aries – sheep. Wool in dressing gown.

Tineola bisselliella – clothes moth. Possible but unlikely.

Gossypium arboreum – cotton, probably present somewhere on Arthur’s person.

Morus alba – again, possible but unlikely. The white mulberry on which the silk worms making any silk Arthur might be wearing fed.

Bombyx mori – silk worm/moth. Could be present in Arthur’s clothing

Hevea brasiliensis – rubber tree. Might be present in Arthur’s slippers.

Saccharum sp – sugar cane. Unlikely, but he might’ve had sugar in his coffee and that might not have been refined.

Beta vulgaria – sugar beet. Mutually exclusive with the previous species. Also, I’m not convinced white sugar still contains any trace of DNA.

Commensal organisms:

Demodex folliculorum – follicle mite in Arthur’s eyelashes.

Candida albicans – thrush yeast. Present in the gastrointestinal tract of about half of human adults.

Gut flora – a large number of species.

Dermatophagoides pteronyssinus – house dust mite. According to the Infocom game, Arthur has fluff in his pocket, which probably contains this animal. Incidentally, this is the European dust mite. The American dust mite would not have survived in all probability.

Hence Trillian could be associated with thirty-seven named species whereas Arthur, despite the fact that we know a lot more about his circumstances as he left Earth, only has twenty-five. Two of them result from his personal violence against animals.

Arthur may not be wearing make up, but he is wearing mud. He lay down in front of the bulldozer. This means he’s likely to be covered in it, leading to such soil organisms as Caenorhabditis elegans and Colpoda, as well as various fungi.

Ford and Arthur are also covered in pollen. This would vary according to the time of year. Perhaps surprisingly, there are only two short date ranges during which the destruction of the Earth could have occurred. We know from the TV series that the Sun rose at 6:30 am on that day. Due to leap years, the date when this happens moves around slightly and due to BST it might be an hour earlier. We also know it’s a Thursday, although this has been disputed because of the football reference. Assuming it’s 1978, the relevant dates are 6th August (Hiroshima Day, rather appropriately), 3rd May and 4th April, none of which are on Thursday. Considering it’s the Vogons, I like the idea that it’s the last day of the tax year, 5th April. If this is so, likely pollens include alder, elm, willow, birch, ash, and, perhaps surprisingly, rather few herbs. Hence the rather obvious privet hedge buffeted by the wind just before Ford activates the electronic thumb is not shedding pollen and hence would only survive if one of its leaves got lodged in Arthur’s dressing gown or PJ’s. Some other plants would already be shedding but not at their peak, including plane, oak and canola.

Other Organisms Leaving Earth Voluntarily

There are two other types of animal who left Earth or were unaffected by its destruction. One of these was the dolphin. It isn’t clear whether this means all dolphins or a limited or unique species. I’ve assumed it was Tursiops truncatus, the bottlenose dolphin. They left Earth shortly before the Vogons arrived, having failed to be communicate the warning although I’m not sure what we could’ve done to prevent it really. They may have taken a food supply with them or simply had half-digested fish in their digestive systems, so that would include herring, mackerel and possibly krill. Other species include mullet, cephalopods, conger eels, hake, bandfish (in this case I didn’t know those existed in the first place) and porgies. Regarding internal parasites, there’s Cryptosporidium, a protist, Ascaris, a nematode, Giardia, another protist and Nasitrema, a trematode, but the question arises of whether the dolphins would use the opportunity to rid themselves of these or perhaps recognise their role in their health, as they might reduce the prevalence of autoimmune conditions. Whale lice would also be present if they chose to keep them. Just as humans are covered in pollen, dolphins and their prey are covered in phytoplankton, such as diatoms. Hence various single-celled algae can be expected to be salvageable.

The final category appears to be mice and the organisms associated with them. Again, it isn’t clear whether it’s just Mus musculus or several species of mice involved. I’m going to assume the former, but note also that whatever the original mouse was, they had time to evolve. What we think of as mice are of course merely the three-dimensional projections of hyperintelligent pan-dimensional beings, and being mice is just the day job.  Nonetheless, Trillian took her mice with her and can therefore be presumed to have taken their food. Mice are of course omnivorous, like most or all rodents, but are sometimes assumed to be herbivorous. In 1978, mice were fed a mixture of seeds and pellets of some kind which I couldn’t identify but may have been minced up insects or something. The seeds included sunflower, split peas, lentils and presumably peanuts. Mice get parasites like dolphins and humans but it’s unlikely Trillian’s would have any. It’s hard to know whether to count mice as native to Earth in the H2G2 universe, as they aren’t what we think they are.

Several issues remain. One is that Earth being only ten million years ago, all the fossils and evolution presumed to happen up until that point are fake, but after that point are probably real. I say fake evolution because DNA analysis would still show an apparent genetic relationship between, for example, humans and chimps even though chimps are native to this planet and humans are not, or between undoubtedly native organisms which were in fact separate creations or not even from the same planet or even dimension in one case. And this is the really weird thing about this whole constructed Earth scenario: Douglas Adams was clearly “a great fan of science” but his version of Earth is almost creationist, though not exactly young Earth creationist. The arrival of the Golgafrinchams led to the replacement of hominins by alien humans, since humans are aliens, and also possibly the introduction of novel species such as grapes, olives and lemons, and maybe also various other species which also replaced their native counterparts or successfully competed with species in similar ecological niches. Despite all this, all known life on Earth is now established to be related. Is this perhaps because it isn’t just life here which is related, but across the Galaxy? Did panspermia happen? Is it happening all the time? Or did the computer program which ran the Earth have to simulate the wider Universe in order to provide the right data on which to base its calculations? This could mean that Earth simply encapsulates the biomes of the wider Galaxy. Maybe life is just constantly diffusing in and out of Earth’s biosphere and linked genetically to the rest of the Universe.

To conclude, I think this is a good way of illustrating the intentional fallacy. Arthur’s and Trillian’s biomes are quite different from each other, although they overlap. Although Douglas Adams is unlikely to have any conscious intention of writing Arthur as a fuller character than Trillian, if he had written them more equally, Trillian’s biome would have been as certain as Arthur’s. This is in spite of the fact that Arthur is supposed to be “Everyman”, i.e. a close to blank slate, though quintessentially English, in whose position the reader is supposed to place herself. Trillian absconded from Earth in its prime, and because her gender stereotype is more clearly constructed than Arthur’s, she takes more of the planet with her when she goes. It’s expensive being a “girl”, meaning that whereas it’s alleged to be optional to present oneself as feminine as a woman, in many contexts this will place one at a disadvantage or put one in danger. Adams is also sketchier about Trillian’s background because he’s writing about what he knows, and he doesn’t know women in the same way as women know women. Moreover, Trillian leaves Earth willingly whereas Arthur has to be prised away from it even though he’ll die otherwise, which somehow reminds me of “women get sick but men die”. On the other hand, Trillian may be too compliant for comfort.

A few more things can be drawn out of this:

• H2G2 is oddly “creationist”, but “middle-aged Earth Creationist” rather than young or old Earth, despite Douglas Adams being proselytisingly atheist. This is also similar to Terry Pratchett’s ‘Strata’.
• Recent developments in DNA sequencing would be expected to have revealed that there was more than one line of evolution leading to organisms on this planet. Larry Niven did something similar with the Protectors.
• Terms used for certain items in the H2G2 universe are known to have wider references than they are usually used. This is acknowledged in the case of jynnan tonix and implied with ouisgiansoda, but may be much wider than is at first apparent. For instance, it may include “rubber”, “lemon” and “milk”.
• As the H2G2 universe is infinite, there are countably infinitely many identical species to those found on Earth in any case. This too is suggested in the text with the ratchet screwdriver trees, mattresses and the Babel fish.
• What would a gender-swapped version of H2G2 be like? What would this version be like told from Trillian’s perspective? Would gender-swapping include Marvin, Eddie and the Nutrimatic Machine?

Sodding Phosphorus!

Here is a sample of the aforesaid element:

Phosphorus has two main forms, or allotropes. When first extracted, it’s white and extremely toxic. The form illustrated above is red phosphorus of course. Left to itself, white phosphorus gradually turns into its red form, which is why the so-called “white” allotrope usually looks yellow:

By BXXXD, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=1096986

This is not, however, supposed to be “all about phosphorus”. Rather, it’s about two issues which affect the element, both to do with life, one on this planet and one in the Universe generally.

I’ll start by explaining the importance of phosphorus to life as we know it. There are six elements making up most of the body of a living organism on Earth. These are carbon, hydrogen, oxygen, nitrogen, sulphur and phosphorus. Carbon is important because it can form chains and rings from which complex molecules can be built. It’s notable that even though silicon is far more abundant on this planet than carbon, life is nonetheless carbon-based. This is to do with things like carbon’s ability to link itself into chains, form double and triple bonds with other atoms, the fact that its atoms are small compared to silicon and the difficulty of getting silicon out of molecules such as silica which may be formed as a result of any putative biochemical processes. Carbon dioxide, the analogue of silicon, is a gas at fairly low temperatures and can be incorporated into other structures. It so happens that I do think silicon-based life is possible, but it would have to be created artificially and exist in some kind of closed environment whose contents were carefully selected. The chances of silicon-based life arising without intelligent intervention are very low. The greater terrestrial abundance of another element should be considered again here, but not right now. Hydrogen and oxygen are of course the constituents of water, a compound which is really unusual in many ways, such as its unusually high melting and boiling points on the surface of this planet, its ability to dissolve other compounds and the fact that it gets less dense as it cools below 4°C. These properties mean respectively that the chemical reactions needed for life as we know it can occur at a temperature where there’s enough energy for them to take place but not so much that they’d be unstable, that the compounds are in a liquid medium conducive to reactions in the first place and that the oceans, lakes and rivers don’t freeze solid from the bottom up. The two constituents are useful in their own right. Oxygen and hydrogen are components of countless compounds, including carbohydrates, amino acids, proteins and fats. Oxygen, unlike chlorine which has been considered as a possible alternate breathing gas for alien life, can form two bonds, meaning that it isn’t the dead end single-bonding atom which the halogens are. Nitrogen is a essential component of protein via its presence in amino acids. Amino acids have a carbon connected to a carboxyl group and an amino group, which can bond together to form chains, and a functional group such as a benzene ring or a sulphur atom which can have other biological functions. Proteins, in other words. There are also chemicals called alkaloids which occur mainly in plants and vary a lot, which have striking pharmacological effects, and the nucleotides are also rings containing nitrogen, encoding genes in DNA and RNA. Nitrogen is actually so reactive that it bonds strongly to other atoms, including other nitrogen atoms, and consequently it’s vital that various organisms can uncouple it and combine it for the benefit of the rest of the biosphere. This is known as nitrogen fixation and is performed mainly by bacteria and certain plants, and also by lightning, but if life had to rely on lightning to do this, it would not be widespread and nitrogen fixed by lightning would be the limiting factor in global biomasse. Sulphur is significantly found in a couple of amino acids and allows proteins to form more complex shapes as are needed, for example, by enzymes and hormone receptors, because they form bridges with other amino acids making the molecule tangle usefully together. It’s also found in hair, nails and various other substances such as the substances responsible for the smell of garlic and onions. Sulphur is actually a bit of an exception in the chief elements required for life because sometimes it can be substituted by either selenium or tellurium, and there are amino acids which have these elements in sulphur’s place, but both of them are much scarcer than sulphur.

Then there’s phosphorus. Phosphorus has more limited functions than the others but these are incredibly vital. It forms part of adenosine triphosphate, which organisms use to transfer energy from respiration to the other functions of the body. It also forms part of the double layers of molecules which form membranes and allow controlled and specialised environments to exist in which the chemical reactions essential to life take place, and also enables substances to be packaged, as with neurotransmitters. Thirdly, it forms the strands of sugar phosphate which hold DNA and RNA together, so even if it didn’t do anything else, some kind of method would have to exist to store genetic information. This is perhaps the least vital role though. A more restricted role is found in most vertebrates, in that it forms part of the mineral matrix of bones and teeth, but there’s plenty of life that doesn’t do this and the usual substances used to make hard parts of animals are silicates and calcium carbonate, among other rarer examples such as iron pyrite. Nonetheless, humans need phosphorus for that reason too, as do our close relatives. However, even the closely related sea urchins use calcium carbonate instead.

Hence several facts emerge from all this. One is that an apparently similar and more abundant element can’t necessarily be used for a similar function, assuming here that life can start from scratch. Another is that elements can get themselves into such a strongly bound state that it would take too much energy to use them for it to be worth it for life. A third is that life will sometimes substitute another element for the one it usually employs if it can. If a rare element is used, there’s usually a good reason for it.

Now the first problem with phosphorus is that it’s much more abundant inside a living thing than in its non-living environment, and the cycle that replenishes it is very slow. Phosphorus usually becomes available to the biosphere on land as a result of continental drift, the formation of mountains and erosion and weathering, and it’s lost to the land when it’s washed into rivers and the sea, where it disappears into sediment before becoming available again millions of years later. In the sea, it’s less of a problem but still a significant one because it’s only available to life as phosphates and it’s often found as phosphides instead. Ironically, there’s also an overabundance problem with phosphates in fertilisers being washed into bodies of water and leading to algal blooms, which can in fact be of cyanobacteria rather than algæ as such. Since some microörganisms can produce extremely powerful toxins, this can lead to massive marine die-offs and contaminated sea food. Where I live, a nearby reservoir was afflicted by an algal bloom and had to be closed off for quite some time, and this can also poison wildlife on land. These can also lead to high biochemical oxygen demand, which is where all the oxygen gets used up and the water becomes anoxic, which is incidentally a cause of mass extinctions, though on a much larger scale, in the oceans. This happens because phosphorus is relatively scarce and a significant limiting factor in how much life is possible in a given area, so a sudden influx of usable phosphate is likely to cause a chemical imbalance.

The Alchemist Discovering Phosphorus, Joseph Wright, 1771 and 1795.

This painting is thought to refer to the discovery of the element by Hennig Brand in 1669. Brand discovered it when searching for the Philosopher’s Stone, by heating boiled down urine and collecting the liquid which dripped off it. It turns out that this is actually quite an inefficient process and it’s possible to extract a lot more of the phosphorus by other means. The allotrope illustrated in the painting is unfortunately the highly toxic and dangerous white variety, so the alchemist is putting himself in peril by kneeling so close to the retort. The point to remember in all this is that phosphorus is found in urine, not in huge amounts but enough. This points towards a particular problem, highlighted by Isaac Asimov in his 1971 essay ‘Life’s Bottleneck’, which points out that humans “may be able to substitute nuclear power for coal, and plastics for wood, and yeast for meat, and friendliness for isolation—but for phosphorus there is neither substitute nor replacement”. Urine goes down the toilet and is flushed into the sewers, processed in sewage farms and the phosphorus from it ends up in the sea. It does gradually return to the land in biological ways. For instance, a seagull may die on land and her bones may become part of the terrestrial ecosystem, or she might just poo everywhere and return it that way, but the occasional gull or tern conking out in Bridlington is no compensation for millions of people flushing the loo several times a day. By doing this, we are gradually removing phosphorus from the land and returning it to the sea, whence it won’t return on the whole for millions of years.

Two ways round this suggest themselves. One is to eat more sea food. For a vegan, this is unfeasible and in any case fishing causes a lot of plastic pollution and is unsustainable, but of course it is possible to eat seaweed, and I do this. The other is not to allow urine into sewage in the first place or to process sewage differently. I have been in the habit of dumping urine in the garden, although I haven’t done this as much recently. It also contains potassium, and in particular fixed nitrogen, so in diluted form it is indeed useful for raising crops. However, this is on a small scale and a better system might be to process the sewage differently and put it on the land, being careful to ensure that harmful microbes and medication have been neutralised before doing so. Regarding seaweed, dulse, for example, is 3% of the RDI of phosphorus by dried weight, compared to the much lower amounts in most fish. Cuttlefish is the highest marine animal source. Human urine averages 0.035%, so you’d have to eat a lot of seaweed. However, in isolation, if you don’t, there will be a constant loss of phosphorus to the land. Guano is one solution, but not ideal and only slowly renewable.

The other problem with phosphorus follows from the same scarcity and the same use in living systems, but is more cosmic in scale, and I personally find it more worrying: phosphorus is rare on a cosmic level. In a way, all atomic matter is rare in this sense because the Universe is, as the otherwise really annoying Nick Land once said, “a good try at nothing” (apparently nobody has ever quoted that before, so that’s a first!). The cosmic abundance of the different elements looks like this:

The Y axis is a logarithmic scale, so for instance hydrogen is about ten times as abundant as helium and even in terms of mass is more common than any other element except helium. One notable thing about this graph other than the clear rapid decline in abundance with atomic number (the X axis) is that it zig-zags because even-numbered elements are more frequently found than their odd-numbered neighbours. This is because many elements are formed by the collision of α particles, which consist of two protons and two neutrons. Phosphorus is flanked by Silicon and Sulphur on here, though it isn’t specifically marked, and its atomic number is fifteen, i.e. an odd number. Chlorine, which is quite common in living things because it’s part of salt, is less common still.

Elements are formed in various ways, and this relates to how common they are. The Big Bang led to the formation of mainly hydrogen and helium a few minutes later, as soon as the Universe was cool enough to allow their nuclei to hold together and their nucleons to form, although they would’ve been ionised for quite some time rather than being actual atoms. Small amounts of lithium and beryllium formed in the same way, and if the graph is anything to go by this looks like it might’ve been the main way beryllium in particular formed. Then the stars formed and the pressure inside them led to helium nuclei in particular being pushed together to form heavier elements. The crucial step in this phase is the formation of calcium when three helium nuclei collide. Then, a number of other things happen. The star may end up going supernova and scattering its heavier elements through the local galactic neighbourhood. It may also form new elements in the process of exploding through radiation. This was until fairly recently thought to be the main means heavier elements were formed, but another way has recently been discovered. When a star not quite massive enough to become a black hole collapses, it forms into what is effectively a giant atomic nucleus the size of a city known as a neutron star. When these collide, they kind of “splat” into lots of droplets. Neutrons are only stable within atomic nuclei. Outside them they last about a quarter of an hour before breaking down, and they often become protons in doing so. This means that many of the neutronium droplets form into heavier elements, which are then pushed away by an unimaginably powerful neutrino burst from the neutron stars and again scattered into the galactic neighbourhood. Two elements, beryllium and boron, are mainly formed by cosmic rays splitting heavier atoms. Some, particularly transition metals such as chromium and manganese, formed in white dwarf stars which then exploded, and technetium along with all the heaviest elements, have been generated by human activity.

At first, the abundance of phosphorus didn’t seem to be a big problem. However, after studying supernova remnants, scientists at Cardiff University seem to have found that there is a lot less produced in supernova than had been previously thought. This means that phosphorus is likely only to be as common as it is here in this solar system in star systems which formed near the right kind of supernova to generate it in relatively large amounts. Couple this with the essential function of phosphorus in DNA, RNA, membranes and ATP, particularly the last, and it seems to mean that at this point in the history of the Universe, life as is well-known on Earth is likely only to be found in initially localised areas, surrounded by vast tracts of lifeless space. The systems containing life would gradually separate and spread out through the Galaxy due to the migration of the stars as they orbit the centre of the Milky Way, but they would remain fairly sparse. However, as time goes by and the Universe ages, there will be more such supernovæ and phosphorus will slowly become more common, making our kind of life increasingly likely. If life always does depend on phosphorus, we may simply be unusually early in the history of the Universe, and in many æons time there will be much more life. This possible limitation may have another consequence. We may be living in a star system isolated from others which are higher than average in phosphorus, meaning that to exist as biological beings with a viable ecosystem around us elsewhere, we would either have to take enough phosphorus with us or make our own, and even the several light years between stars which we already find intimidating is dwarfed by the distances between phosphorus-rich systems in the Galaxy, which may once have been near us but no longer are, and not only do we have to schlep ourselves across the void, but also we have to take a massive load of phosphorus with us wherever we go.

But that is biological life as we know it. A couple of other thoughts occur. One is that there could conceivably be life as we don’t know it. This doesn’t work as well if the substitution of phosphorus is the main difference, because if that could happen, it presumably would’ve happened with us, and it didn’t, because other elements with similar functions would’ve worked better if they were more abundant and out-competed with the life which actually did arise unless there’s something about this planet which does something else like lock the possible other options away chemically or something. However, there could just be drastically different life, based perhaps on plasma instead of solid and liquid matter on planets and moons, which has no need for phosphorus or even chemistry, on nuclear reactions taking place between nucleons on the surface of a neutron star as suggested by Robert L Forward’s SF book ‘Dragon’s Egg’, or even nuclear pasta inside neutron stars. Maybe it isn’t that life is rare in the Universe, but that life as we know it is, partly because it needs to use phosphorus.

There is another possibility. We are these flimsy wet things crawling about a planet somewhere in the Galaxy, but we’ve also made machines. In our own history, we are the results of genes, and perhaps also mitochondria and flagella, concealing themselves inside cells and proceeding to build, through evolution, relatively vast multicellular machines to protect themselves. Maybe history is about to repeat itself and we are going to build our own successors, or perhaps symbionts, in the form of AI spacecraft which go out into the Universe and reproduce. Perhaps machine life is common in the Galaxy and we’re just the precursors. There is an obvious problem with this though, mentioned a long time ago: what’s to stop swarms of self-replicating interstellar probes from dismantling planets and moons and making trillions of copies of themselves? If this arises through a mutated bug in their software, it would be to their advantage, and they could be expected to be by far the most widespread “life” in the Universe. Yet this doesn’t seem to have happened. If it hasn’t, maybe the beings which built these machines never existed either. Or maybe they’re just more responsible than we are.

Racism And Astronomy

I am of course incredibly White, so the immediate question here is why a White non-astronomer is qualified to talk about racism in astronomy. Well, strictly speaking of course I can’t really, or rather, I am unlikely to be able to wade into it in enough depth to swim knowledgeably. Nonetheless I can give a kind of overview of it and comment on some of the active racism involved.

Photo by Faik Akmd on Pexels.com

This is a time lapse picture of the night sky. The main reason we can know it was taken here on Earth, apart from the fact that astronomical pictures taken from other celestial bodies are rare and poor quality (in fact I only know of one body they have been taken from, and that’s Mars) is the colour of the sky and the presence of liquid and solid on the surface at the bottom of the picture. It also seems to have been taken from the northern hemisphere because of the relatively stable and bright streak at the centre, which is presumably Polaris. Had it been taken from the south, the much dimmer Sigma Octantis would be at the centre of the swirl.

The sky seems non-specific and impassive to us, and also very little influenced by conflict or politics going on here on Earth among humans, and that is one reason I’m so keen on astronomy. Contemplating the Universe makes the problems we have here seem less important and seems to put them in perspective. I would personally say the stars are something to aspire to. I so want there to be humans out there among them one day. Of course, we are already among the stars but apparently only one of them hosts us. Nevertheless, there are cultural dominances and biasses in how we view the Universe and also very clear and overt racism exists among the astronomical community.

This sounds like an accusation, as the words “racism”, “sexism”, “ableism” and others often do, but that would imply that people are consciously and deliberately reserving much of the academic world to White people. That may happen as well, but it’s more important to look at the issue as a structural thing. As a White person, I have the privilege of firstly being unaware of racial bias among astronomers and secondly of being able to contemplate astronomy in a meaningful way. There are other ways in which I am trivially disadvantaged to do with my situation. For instance, I can’t see objects in the night sky very easily because of my poor eyesight, so the best I can usually manage to do is to view maybe first magnitude stars such as Antares, and basically nothing else. This is more on the disability side than ethnicity of course, but there is another set of issues which is fairly obvious to me regarding gender, namely that a man may feel much more confident to go out at night to a park or remote area to look at the sky in a place without light pollution than a woman might, and beyond that the kind of systemic biasses which prefer able-bodied middle-aged WASP men work against women, the disabled and ethnic minorities. Hence in the richer parts of the world, Black people are likely to live in places with more light pollution and less likely to be able to afford a good telescope. Ironically, much of Afrika, for example, would be very suitable indeed for telescopic astronomy. Here’s a map of the continent showing lighting at night:

(would’ve been better without the labels). And here’s Europe:

This means that treating every location as equally likely, which is not so because of lack of population, one stands a much better chance of seeing the night sky well in Afrika than in Europe. Also, along the Equator one can see both celestial hemispheres, so one can see more of it in Afrika than Europe.

There will inevitably be systemic racism in who becomes an astronomer in Europe and North America, although I’m guessing this isn’t any worse than who becomes a palaeontologist. The latter presents a rather different problem as there are issues regarding the plunder of resources by colonialists and the treatment of indigenous peoples and ethnic minorities in the field, which may not be so big a problem with astronomy. However, there can be problems with the siting of observatories in a similar sense, the most well-known one at the moment being the positioning of the Thirty Metre Array in Hawai’i, which was to be situated on Mauna Kea, a sacred site to the people of that archipelago. The issue here is that the planned observatory is one of several near that site, and in the past the excavation of the site has desecrated the graves of ancient high chiefs. In the past, promises regarding the building of telescopes have been broken, with insistence that this would be the last development, followed by more of the same. The northern hemisphere is low in such observatories, and a possible alternate site in La Palma in the Canary Islands is less suitable for infrared astronomy due to the warmer climate and lower elevation. Mauna Kea is the highest mountain on Earth measured from its base, so there’s less atmosphere to look through. There is a peaceful protest ongoing there. Some of the indigenous people view the idea of looking for other habitable planets as encouraging an attitude that Earth is disposable. Despite losing their case in the courts, the actions taken to build the observatory seem to meet the legal definition of desecration. Elders in their seventies and eighties have been arrested for peaceful protests, and because the site is sacred all protestors are committed to non-violence. This has also divided the community as the police officers are sometimes related to the protestors. Beyond that is the issue of how the United States government acquired the islands in the first place, on the grounds that the White businessmen were more fit to run the island than the recently independent natives. The federal government also had no legal jurisdiction over the country.

This story makes me wonder about whether there are other observatories with similar histories. There is also a separate issue regarding the Arecibo Telescope, which is an enormous radio telescope built in a basin in Puerto Rico. This was used to send the first message into interstellar space for detection by aliens, although it was only a semi-serious attempt for publicity purposes. In 2020 CE, the telescope collapsed, primarily due to lack of funding making maintenance unaffordable. Like Hawai’i, part of the rhetoric for siting the telescope there is that it brings money into the local economy, but that money is no longer forthcoming. Elsewhere on the planet, the Karoo Square Kilometre Array in South Africa requires a 13 000 hectare “quiet zone” which minimises electromagnetic transmissions to enable the telescopes to detect signals from the sky more easily. The San used to live in this region and were forced to move north by the colonial government in the century before last, and there’s the issue of purchase of the land from White farmers to prevent radio interference. Employment is low and deprivation high in the area, and it’s possible that building the extra telescopes may lead to jobs. The San were, however, displaced when the government brought Black farmers to the area some time ago. The SKA is situated where it is thanks to a government bidding process which brought it into the area.

Then there’s the Atacama Large Millimeter/submillimeter Array. This was afflicted in 2013 by a workers’ contract dispute between the Washington CD-based organisation which runs the facility and the four-fifths of employees at the site who are Chilean. All of these things taken together look like a process where scientific institutions in the wealthy and light-polluted (and also electromagnetic radiation more generally) North of the planet uses places with colonial histories to site its astronomical facilities, without much respect being paid to the people who actually live there. As I say, I don’t know much about these things but it seems to be a clear example of racism in astronomy. The Polynesian people and the San do of course also have their own astronomical traditions. Western astronomers were not the first.

In 2017, only nine percent of US STEM academics were POC. The Black population of the US is 13.6%. As for Black women, only sixty-six of them got doctorates in physics compared to 27 000 White men. This is not about problematising STEM departments or the scientific community in particular, but in a racist society this kind of disparity can be expected if nothing is done to address it. In general, diversity is an asset because new perspectives can be brought to bear on research, so this is not simply about justice for ethnic minorities but about having a well-functioning scientific discipline. Problems encountered in physics and astronomy for POC include microaggressions from White students, not feeling welcomed or included, imposter syndrome, a lack of role models, financial struggles and an absence of academic support. There is a second problem with examining racism specifically in astronomy caused by the tendency for physics and astronomy to be lumped together, perhaps because physics is perceived as a more “useful” subject, and it may also be that astronomers are less aware of the need to combat racism in their discipline than physicists. Researchers into the issue have not managed to visit astronomy departments as easily as physics ones, meaning that no firm conclusions can be drawn about the relative differences.

The White Florida emeritus astronomy professor Haywood Smith has state

d that he does not believe systemic racism exists at a time when only two percent of American astronomers are Black. His own department had had one Black employee, in admin, hired in the early 1990s. On the positive side, Black students report that the environment in the department is generally very positive and supportive. However, I can’t help but be reminded of Patrick Moore, who was chair of the right wing United Country Party, which opposed immigration. He was also an admirer of Enoch Powell, condemned the Race Relations Act and regarded the absolute monarchy of Liechtenstein as the “best political system in the world”. This last point is more complex, mainly because Liechtenstein is a microstate, but it still means that, like Britain, Liechtenstein’s head of state is very likely always to be White.

It would be unfair to use both of these astronomers as typical of their profession. Even so, it does remind me of the interesting phenomenon of right wing animal liberationists. There are people whom I might describe as “animal lovers” who look at the world very differently than I do, and whose veganism, if that’s an accurate description, is also very different to mine. For instance, there are some animal liberationists who are anti-abortion and see that as consistent, and there’s also an attitude that whereas humans are terrible, and behave terribly towards each other, other species do not perpetrate deliberate cruelty but simply try to survive and thrive, and take care of their offspring. For such people, other species seem to constitute a similar escape from the woeful interaction of human beings with each other as astronomy does for me. Maybe actively racist White astronomers are similar. I don’t feel I’ve exactly captured the issue, but I can see the sense in this apparently incongruous juxtaposition.

The way it might work for White astronomers is that they want to rise above this morass of apparent nonsense that infests the world, but their nonsense is not the same as my nonsense. Mine is the endless grind of global capitalism, greed and hatred between groups to ensure divided opposition to oppression. Theirs is a reflection of the privilege which enabled them to become astronomers in the first place. It could also be a kind of innocence. They may be so focussed on the stars that they’re oblivious of what’s happening on the ground. But it’s been said that not taking a position in a dispute about oppression is taking the side of the oppressor. Some might also say that there’s an issue with even having astronomy departments “when the world’s in such a mess”. I completely disagree with this though, because awareness of the existence of the rest of the cosmos has a function similar to spirituality and art in allowing one to continue and cope in order to continue fighting for a better world. Being a science, astronomy also has the usual function of science in training people in critical thinking. This is how astronomy graduates will be coming out the other end of the degree machine, whether or not they use their qualification vocationally. Astronomy is also just plain useful, for instance in detecting asteroids hurtling towards the planet and wiping out all life as we know it.

Another aspect of astronomy and racism is the question of sky cultures and names for objects. I’ve already mentioned the Square Kilometre Array and the observatories on Mauna Kea. Both of these are unsurprisingly both associated with indigenous communities, namely the San and Polynesians respectively. A sky culture is how a particular culture sees the sky. There are several Polynesian sky cultures just as there are many Polyesian languages. It could be expected that a set of people who have settled in various places across the Pacific and Indian Oceans would have a highly disparate set of cultures. The Austronesian language family had the largest geographical range of any language family before colonialism: Hawai’i and Madagascar both speak Austronesian languages and are 17 000 kilometres apart. Their broad distribution is a factor in their astronomy, as it was important to have some understanding of constellations in order to navigate. In order to record the positions of the stars, some Polynesians used “stick charts”, made from palm fronds, cowries and plant cordage:

By Sterilgutassistentin – This file has been extracted from another file, GPL, https://commons.wikimedia.org/w/index.php?curid=51775534

Curved links indicate ocean currents and winds and the charts are effectively maps of the ocean. Pacific Islands tend to be around one to three hundred kilometres apart with the exception of such outliers as Hawai’i. The information was memorised and navigators were also spiritual and political leaders, navigation being a spiritual and religious act. Astronomy was part of this. Guiding stars were used when low in the sky, with imaginary vertical lines projected onto the horizon to indicate direction, but these move as the night goes on due to the rotation of the planet. The direction indicated by the star is maintained until another star rises. The paths between these stars are referred to as “kavenga” – “star paths” – named after the brightest star and all stars are referred to by the name of the brightest. However, these are not applicable all year round, so the year is divided into four unequal seasons with different kavenga. These are Ke Ka O Makali’i (the northern winter – Hawai’i has no seasons of course), Ka Iwikuamo’o (northern spring), Manaiakalani (northern summer) and the overlapping Ka Lupu O Kawelo (northern autumn into winter, including some of Ke Ka O Makali’i). Kavenga could also be kept on one side or other of the boat, or the boat could be aimed between two kavenga. There is also the star compass, which uses the presence of Polaris and Crux Australis, as we in the West call them, and the stars around them as they rise and set, to locate the north and south celestial poles. They also picked out a number of other asterisms (star patterns), including what we call Orion’s Belt, Scorpio, and the Pleiades, and used their rising and setting to mark another six points on the horizon and construct the directions in which other stars were since their positions would then be known. This enables the navigator to find out where the boat is when the sky is partly cloudy. There are also, unsurprisingly, stories associated with the star paths and asterisms. Apart from being meaningful in other ways, these serve as mnemonics for the location of the star paths.

There isn’t time to cover all Polynesian sky cultures here, so I will now move on to the San. Although it must be remembered that the biological construction of ethnicity as race is distinctly dubious, politically speaking, it’s also worth noting the identity of the San, whose genetic profiles are highly unusual. The San appear to be the group genetically closest to the earliest examples of Homo sapiens. Both their Y-chromosomal and mitochondrial DNA branched off early from the rest of the species and they seem to have diverged from about two hundred millennia in the past. They’re also the most diverse group of humans genetically. Two San can be as different generically from each other as two randomly chosen people from anywhere on Earth. Besides this, albinos are unusually common among them. I mention all this to indicate that they are very much not simply Black people even though Europeans might lump all Afrikans who are not fair-skinned together. They have a very distinct identity. Afrikans generally are more genetically diverse than the rest of the human race, so as I’ve said previously, if you want a construction of race based on genetics, and I don’t really know why you would, it makes sense to see Afrika as including about ten ethnicities and the rest of the world about fourteen, but with entire continents in some cases only having a couple, so the human race basically consists of a series of genetic groups which often vary in skin tone and other features within those groups plus a large number of mainly dark-skinned groups all of whom originate recently from Afrika. The idea of skin tone as a major feature distinguishing ethnicities makes no genetic sense, and of course people don’t just “breed” within their own hermetically sealed racial units.

One tantalising possibility exists regarding San sky lore, which is that it may be directly descended from early human mythology. On the other hand, behavioural modernity seems to have appeared after the split between them and the rest of the species, so maybe not. One difficulty with recovering it is that Christian missionaries have obscured and suppressed the content, but one story is that a woman was baking a root vegetable on a fire and wouldn’t let her daughter eat it, so the daughter kicked at the fire and scattered the ashes across the night sky, forming the Milky Way, and the red embers formed the red stars in the sky. Kham (the Moon, Cynthia) is a man who has angered the Sun, gains weight each month and then is cut away by the Sun until only the backbone is left, and he pleads that this crescent he has become be left for his children, who then repeat the cycle. The Sun, in a possibly different tribal tradition, becomes a rhino at sunset, is eaten by a different tribe who then throw her scapula over to the east, where it becomes a new animal and rises again. The celestial bodies are the elder race and all personified. The Sun, and again this seems to be a different tradition, is a man with luminous armpits, armpits being considered a source of sweat which contains supernatural power, who refused to share his light to dry out the termites for eating, so the first San threw him into the sky so that his armpits could illuminate the world. The “Moon”, is the shoe of a male trickster deity, /kaggen, the name literally meaning “mantis”, who threw it into the sky, and an alternate theory is that it’s an ostrich feather also throw into the sky by /kaggen, who commanded it to become that celestial body. All of /kaggen his possessions are magically intelligent and the “Moon” alone speaks using a retroflex click. Like many other cultures, there is an association between a lagomorph, this time a hare, and this luminary. The spirits of the dead are carried by the dark side, so the full phase is considered good luck for hunting, as is a blood moon. The stars are named after various animals such as lions, antelopes and tortoises, and a stone used for digging. For them, the sky was a stone dome with holes in it through which the Sun shone. The three stars of Orion’s belt are zebras, the Pleiades the daughters of the deity of the dawn and sky, Tsui. Her unnamed husband is Aldebaran. Betelgeuse is a lion who is also stalking the zebras, so Aldebaran can’t get them without getting killed, so he’s slowly starving to death.

There’s quite a contrast, then, between the sky cultures of the Polynesians and those of the San, and of course there are plenty of others, but the dominant one, used by Western astronomers, is of course the Greco-Roman and more widely European eighty-eight classical constellations with stars named using Greek letters, numbers and often Arabic names. The presence of Arabic in this system demonstrates how the Arab world didn’t go into the Dark Ages like Christendom and for a long time their astronomy was more advanced than ours. There is a clear division in the names of the constellations between north and south because of what was visible from the Med at the time, so the zodiacal and the more prominent northern constellations were given names by the Greeks and Romans, but there are also fainter northern constellations with newer names and the southern names, also given by Westerners, tend to be very different. Some are neutral and uncontroversial, such as Crux Australis and Triangulum Australe, and the southern polar constellation is called Octans due to its obvious association with navigation. Several others have nautical or navigational names, such as Sextans, Quadrans (which is obsolete), Pyxis (the Compass), and some more are named after birds such as Tucana and Apus. The rather dim Indus was named by a Dutch astronomer and is clearly supposed to represent an individual of non-European origin, but their exact ethnicity is unclear due to the practice of referring to native Americans as “Indians”. There are also some obsolete constellations, one of which, Quandrans, has already been mentioned. Unfortunately one of these is Antinous, the homosexual lover of the Roman Emperor Hadrian. There was also a pangolin, and some others whose names seem perfectly normal and acceptable, such as the Cat, the Bee and the Sundial. Others used to be nationalistic or partisan, such as Sobieskii’s Shield, now known simply as the Shield, and Charles’s Oak. Also, in the seventeenth century, an attempt was made by one astronomer to give all the constellations Christian designations, replacing the northern constellations with New Testament names, the southern with Old Testament ones and the zodiac with the twelve apostles. This is a diffeent kind of cultural bias.

I’m sure there’s plenty more to be said about racism and astronomy, but I want to finish by mentioning the recent renaming of certain celestial objects such as NGC 2392, formerly known as “The Eskimo Nebula”. The name “Esquimau” is considered racist because it isn’t what the Inuit call themselves and it was widely believed to mean “eater of raw flesh”. In fact, it may not do but instead may be derived from “Ayeshkimu”, meaning “netters of snow shoes”. However, whatever its origin it’s considered as a colonial term with a racist origin by the Inuit, so the colloquial name has now been replaced by the New General Catalogue number. Similarly NGC 4567 and 4568, twin galaxies, were formerly referred to as the “Siamese Twin Galaxies”, which has again now been dropped. NASA also has an Office of Diversity and Equal Opportunity which addresses issues affecting marginalised groups.

As I said at the start of this post, I am not really the right person to be talking about racism in astronomy as I am White and not an astronomer, but I hope I’ve been able to provide some kind of sketchy survey of some of the issues involved. There’s bound to be a lot more.

Are Humans Embarrassing Or Boring?

This is not either/or, incidentally. We might theoretically be neither embarrassing nor boring or we might be both. Also, when I say “embarrassing”, I might be better off saying something like “shameful” or “social pariahs”. Please bear with me.

This is the famous “pale blue dot” photograph taken by one of the Voyager spacecraft on Valentine’s Day 1990, at which point it was beyond the orbit of Neptune. There is a minute fleck in this picture which I thought at first was a bit of dust on the screen. I tend to make similar mistakes whenever I see this image. Nonetheless, the “ray” on the right hand side has a tiny dot in it, and that’s Earth. Carl Sagan, the popular science guy, once said the following of this picture:

From this distant vantage point, the Earth might not seem of any particular interest. But for us, it’s different. Consider again that dot. That’s here. That’s home. That’s us. On it everyone you love, everyone you know, everyone you ever heard of, every human being who ever was, lived out their lives. The aggregate of our joy and suffering, thousands of confident religions, ideologies, and economic doctrines, every hunter and forager, every hero and coward, every creator and destroyer of civilization, every king and peasant, every young couple in love, every mother and father, hopeful child, inventor and explorer, every teacher of morals, every corrupt politician, every “superstar,” every “supreme leader,” every saint and sinner in the history of our species lived there–on a mote of dust suspended in a sunbeam.

Carl Sagan, ‘Pale Blue Dot’, (c) 1994.

This observation has a lot in common with Douglas Adams’s Total Perspective Vortex storyline from the Secondary Phase of ‘The Hitch-Hikers’ Guide To The Galaxy’, where he imagines a machine which drives people insane by showing them how insignificant they are in a vast Universe. This doesn’t succeed in Zaphod’s case, either because his ego is the size of the Universe or because he was actually in a simulated universe set up for his benefit, or strictly speaking his deficit.

The Fermi Paradox, which in case it’s somehow passed you by I will restate here, was voiced by the nuclear physicist Enrico Fermi in 1950, although Konstantin Tsiolkovskii had said something similar in 1933 and suggested the Zoo Hypothesis as a solution. Simply stated, it’s the apparent discrepancy between a Universe in which life is possible and the lack of evidence for the existence of aliens. That is, given that there is intelligent life on Earth, as is often claimed, and that Earth and the Sun are both quite unremarkable, why haven’t we had any contact with intelligent life forms from elsewhere in the Universe? Not only is there no apparent evidence today, but nor does there seem to have been any visitation from aliens at any time in the whole 4 600 million years since this planet formed. Since I’ve mentioned the Zoo Hypothesis, I should probably explain what that is. It’s the idea that we are known to aliens but they have chosen not to interfere with us, at least so far, so as to observe us as an interesting species.

This is actually the solution I favoured as a teenager. I liked the idea that there was a Galaxy teeming with intelligent life forms of various species out there with an ethic of non-interference, who were observing our species undetected. This is also very similar to the Prime Directive of the ‘Star Trek’ universe.

Right now, I have a much more depressing front runner as to the solution, although it’s not as much of a downer as the Great Filter, which now I’ve mentioned it I’ll have to outline, but later. At this moment, the most plausible explanation seems to me to be that phosphorus is relatively scarce. This argument goes as follows: non-carbon based life is unlikely because on this planet silicon is more abundant by far than carbon and yet there’s no silicon-based life here. Phosphorus is the rarest core element required for life as we know it, being incorporated in adenosine triphosphate and nucleic acids such as DNA, and it being so rare suggests that it wouldn’t be used unless there was no alternative. Then it turns out that phosphorus is even rare in our own solar system off-Earth. It’s ten times more concentrated in the human body than in the crust, and more than a thousand times as concentrated in the crust than in the matter of the solar system. Phosphorus only seems to form during a particular kind of supernova explosion, as opposed to within the star before it becomes a supernova and distribute the elements, meaning that phosphorus may only be at all common in certain parts of the Galaxy, and that also may prevent intelligent spacefaring civilisations from spreading far because they might have to take all their phosphorus with them or make it in situ. Moreover, it may be that as the Universe ages more phosphorus will accumulate and it will become more hospitable for life, which means we might just be really early.

I hope this is either not true or that another form of life dominates the Universe, such as plasma-based life living in nebulae or the depths of space between the stars. Nonetheless many other explanations have been offered, one of which is primarily interesting for the purposes of this blog post because of its origin: the Dark Forest.

There’s a famous and celebrated trilogy of SF novels by the Chinese author 刘慈欣 (Liu Cixin). I won’t go into the details of the plot, but the overarching idea in it is that the reason we haven’t heard from aliens is that the rational approach to the existence of extraterrestrial life is to regard it as a threat, and therefore that they’re all hiding due to the threat, and making oneself known, as we have if there’s anyone out there, is foolish and suicidal. More generally Liu Cixin believes that we project artificial positivity onto aliens, regarding them as more enlightened and benevolent than it’s reasonable to expect them to be, while simultaneously underestimating the benevolence of humans. I don’t agree with this at all as I think it’s based on how groups of human beings have behaved under patriarchy towards each other and there’s no reason to suppose aliens have the same characteristics and history as our highly contingent tendencies. However, one interesting aspect of the Dark Forest hypothesis, as it’s known, is that it’s an idea from fiction which has turned out to be taken seriously by theorists dealing with the real Fermi Paradox, and the same is true of the two main ideas I want to talk about today.

The first of these is that we’re embarrassing, and for this I’ll go back to Douglas Adams. In ‘Life, The Universe And Everything’, the (obvious spoilers) premise is that the reason aliens are always invading Earth is that they find the game of cricket to be in extreme bad taste due to a devastating war early in Galactic history. Taking this up and running with it, what if the reason we are not in contact with aliens is that there’s something about the way we are which does something like make us a cognitohazard to them, or that our behaviour or values are so reprehensible that we can’t be accepted in polite society? Maybe we are metaphorically wearing our underpants on our heads, or are like the racist uncle who can’t resist making off-colour jokes.

To state this more clearly, there are intelligent life forms elsewhere in the Universe, and they are aware of our existence. The reason they don’t make contact is that there is something about us they find abhorrent, not physically speaking but along the lines of our customs, culture, values or practices. They find us rude or to have crossed a line they would never dream of doing. Alternatively, they can’t contact us safely because our behaviour constitutes something which would infect their psyche and cause severe damage to their civilisation.

There’s a peculiar visual phenomenon which I’m going to suggest you don’t Google (will that verb be dated soon?) called the McCullough Effect (I’ve deliberately spelt this wrong). It’s hazardous to search for this online, and I have reason to suppose it might be more hazardous for me than the average person. It takes the form of two patches of black and white stripes, one set horizontal and the other vertical. If you look at them for a few minutes, black and white horizontal stripes look pink and black and white vertical stripes green, for a period of about three months. The idea isn’t new, but as far as I know this is the only real world example that’s been discovered so far which works on neurotypical people with good colour vision. My hypothesis here is that there is something about us as humans, or possibly our dominant culture, which has a similarly but possibly more severe harmful effect on aliens who come into contact with us, and therefore we have been quarantined to protect the rest of the Galaxy. If this is true, it isn’t clear to us what it is or whether it’s all-pervasive or permanent.

There’s a less morally-neutral version of this possibility. Maybe our selfishness and materialism have led to us being cast out of the Galactic community, but we aren’t permanently bound to it, and if we free ourselves from it as a species they may make contact. This sounds a little like the idea of the “Fall Of Man”, and one shouldn’t underestimate the role mythology or spirituality may play in causing this idea. Or, it could be something we just can’t guess at, as with Douglas Adams’s example that it’s because some humans play cricket. It could be something as arbitrary as that, which will never occur to us because it’s part of being human. Maybe we’re being shunned, in other words.

The other possibility is suggested by Iain M Banks’s story ‘State Of The Art’. Obviously I need to flag up spoilers here too, but I also need to get on. In this novella, a post-scarcity civilisation called the Culture surreptitiously visits Earth in 1977 and decides that it’s so average that it’s not worth making contact with us. I didn’t get this from the story myself but apparently that’s how most people read it.

To state this more clearly, the solution to the Fermi Paradox is this. We are in a vast and life-rich Galaxy, with plenty of advanced technological civilisations, and we just aren’t that interesting. It isn’t that there’s anything particularly wrong with us or that we’re being studied as the Zoo Hypothesis has it, just that we’re really boring and ordinary. In this scenario, there could be numerous planet-bound civilisations like ours which are also wondering where all the aliens are, but the advanced aliens have all been there and done that, and don’t have much interest in a history of a typical primitive but intelligent species living in a boring old ordinary solar system. We’re simply “Mostly Harmless”, to get back to H2G2. The scale of the Galaxy is such that paying any attention to us would be like getting fixated on a bit of mouldy bread accidentally dropped behind something in the kitchen, which might be interesting to a mycologist but unless it really starts to stink or something, they’re not going to pay much attention to it/us.

This explanation has the merit of according with what we already know about our apparent place in the Universe. We’re on a pale blue dot lost in the vastness of the Cosmos. I had to peer at that picture for a while before it registered with me that Earth wasn’t a random fleck of lint or a bit of dandruff. It is feasible that some kind of survey of the Galaxy could have been undertaken which picked us up, but it’s like a huge shoal of fish. There’s a species of fish called the Lanternfish. Actually there isn’t. There are more than thirty genera of this fish, and it’s a good illustration of my point that I didn’t even know that. The remarkable thing about lanternfish is that they are so numerous that there may be up to sixteen billion tonnes of them in the ocean and they may be the most populous vertebrate in the world. They live in the middle depths of the ocean throughour the world, and in that sense they are important. Their average weight is 250 milligrammes, so a low estimate of their global population is a million times that of the total population of humans in the world. But have we heard of them? Do we think much about them? They’re also one of the most diverse families of fish in terms of number of species, but this still doesn’t really matter to anyone apart fom a few specialist experts. Now consider a single lanternfish. Being a living being, of course it’s important and I’m not about to suggest that I consider it disposable or not worth keeping alive, but to the average person, who is going to care about or even think about such a fish? Maybe this is what the planet Earth and its human population is like to the Galactic community. There is maybe someone in an alien university thousands of light years away who has considered our civilisation as part of their PhD thesis, as a footnote somewhere in a book nobody will ever read, or whatever the alien equivalent of that is, but even that’s a pretty long shot. The sheer scale of the Galaxy supports this idea.

Both of these suggestions have in common that the question “where are all the aliens?” is kind of inverted. It’s more like the Biblical quote “Who is man that Thou art mindful of him?” Maybe the real question is why we would consider ourselves worthy of attention. On Earth, we are a big deal, a big fish in a small pond, but in the Galaxy perhaps we’ve either mistaken a fireplace for a urinal in the home of a prospective in-law or we’re like an individual lanternfish swimming a kilometre down in the Southern Ocean and nobody has any reason to care.

«Je ressens la pluie d’une autre planète»

It’s a trite cliché that artists have to draw what they see, and with twentieth and twenty-first century art it seems to be false. Perhaps with Fauvism an artist might attempt to concentrate on how she might see a particular shade or hue and paint it as that colour throughout, or at least that’s the impression (!) I got. In fact it seems to be nothing like that, but it does force the viewer to see the geometrical components of a scene while retaining one’s emotional relationship therewith, or maybe the artist’s feelings. Cubism, a couple of years later, concentrates on geometry while removing emotion.

Right now I feel that my tour of the Solar System has to some extent placed me in the second category, but only somewhat. I expect, if someone had genuinely visited other worlds, if their experience of Earth on their return would be more emotionally charged. I’m sure they’d never be the same again.

There will be something like poetry. Where it starts is another matter.

In the park near us, there’s a small fountain in a pond. Its drops describe a series of parabolas. These parabolæ radiate from the central showerhed and rise maybe fifty centimetres from the water surface. They remind me, right now, of nothing so much as a volcanic eruption on Io. With its exceedingly tenuous atmosphere and gravity less than a fifth of Earth’s, the fountain of ejecta from Io’s volcanoes resembles the fountain in the park but is cyclopean in extent, being over 150 kilometres high. However, the same laws of physics govern the movement and form of the drops. This was the first alteration in perception I became aware of.

Swerving into herbalism territory, like most Western herbalists my stock-in-trade substantially comprises a series of bottles containing what probably look like thick brown liquids to most people. These are usually ethanol and water solutions containing dissolved active ingredients of the plants in question. I could go into more depth about the more subtle distinctions herbalists perceive in the appearance of these tinctures, but for quite a number of them the residue remaining if some is spilt and the solvents evaporate becomes a tarry, often reddish-brown substance which is often a mixture of tannins and other compounds. Tannins are generally linked rings of organic molecules with hydroxyl and oxygen groups. Bakelite is another example of a substance made of these phenolic rings, and the brown or black appearance of a caster, mains plug or saucepan handle is often due to this. And out there in the depths, or maybe heights, of the outer Solar System are countless worlds covered in tholins, which are in some ways similar to this residue, though not necessarily phenolic. The sticky, reddish-black tincture residue is substantially similar to the same stuff coating the surface of many TNOs.

Another parallel with herbalism occurs when certain worlds are cold enough to have frozen nitrogen on their surfaces, such as Pluto and Triton. This brings tholins into contact with the element, leading to the formation of organic compounds containing nitrogen. These are quite similar to alkaloids. Alkaloids are a group of compounds which each have some of the following characteristics: they all contain nitrogen and have a markèd physiological action, tend to have rings including a nitrogen atom, and originate from plants. There are exceptions to the last two and the function of the alkaloid for the plant in question isn’t clear – they may act as reserves of fixed nitrogen. Alkaloids include caffeine, nicotine, atropine and cocaine. There are research programs to find novel alkaloids in rainforest plants for medical use, a race against time thanks to deforestation. Well, heinous as that may be, it so happens that many outer system worlds are coated in nitrogenous organic compounds, and this is just me but I do wonder if there are many such compounds out there. Maybe there could be heroin mines on Charon. The Universe doesn’t care about that.

The way tholins spread across the surfaces of the likes of moons and asteroids is reminiscent of how mould, lichen or plants colonise a new habitat. They are, as I’ve said before, a fork organic chemistry can take when free from technological influence instead of coming alive. It’s literally true to say that there’s an organic quality to tholins. Alternatively, maybe the way tholins went on Earth involved a freak accident with them coming to life. Consequently, when I look at a road surface, wall, pavement or other stone-like artifact, I see a parallel to the surface of a distant planet, where reddish-brown tar is gradually being deposited, just as moss and lichen gradually creep across these fresh plains. The difference is that in spite of the amazingly gradual encroachment of lichen at about a millimetre a decade, it’s still thousands of times faster than the rate of tholin deposition.

I don’t know if you’ve ever been to Dungeness. This area of Kent, held constantly in place by shingle lorries shuttling to and fro 24/7, is an example of a rare type of habitat known as a shingle bank whose largest examples on Earth are it and Cape Canaveral. The delicacy of this landscape is such that walking across it will leave footprints visible decades later due to the slow-growing foliose lichen living there. It has to be said that putting one of NASA’s main launchpads there is rather questionable, and much of what I’ve been able to write about in this series is contingent on environmentally questionable launches from that location. Dungeness at least has a lot in common with the lunar surface in that the footprints and human influence there, and doubtless in Cape Canaveral too, are extremely durable. Dungeness has been compared to “the surface of the Moon”, and this could equally well be inverted to comparing the surface of a distant planet to Dungeness. Titan in particular springs to mind.

On the whole, the view from moons, planets and asteroids on the Universe is either obscured or clear. There is a strong tendency for conditions to be close to extreme here. Either the sky is completely clear or completely cloudy. This is not universally so. For instance, on Mars clouds do occur but on the whole the sky is empty of them. Earth is cloudier than Mars but not as cloudy as Venus. This is one situation where I may not be aware of conditions outside the British Isles and over much of the planet the sky is either usually clear or mainly cloudy, but there are even so areas where there are, for example, little fluffy clouds in a blue daytime sky. The clouds on this planet are usually mainly water ice or water vapour, but the volcanoes are usually silicate rocks.

It needn’t be this way. Martian clouds are generally either water ice or dry ice, i.e. carbon dioxide. On the outer planets they’re various, sometimes evil-smelling, substances like ammonium hydrosulphide or hydrogen sulphide. On Titan they’re methane, and form a largely uninterrupted deck of obscurity. One notable thing about all these clouds is that none of them actually constitute a substantial part of the world in question’s atmosphere. Our own atmosphere, for example, is not mainly water vapour, and if it was this planet would be very like Venus and completely uninhabitable with no rivers, lakes, seas or oceans, because steam is a much stronger greenhouse gas than carbon dioxide. Likewise with the prominent clouds elsewhere in the Universe. Even so, there are circular storms, thunderstorms and plenty of cloud types approximating our own, as well as the same formations. On Mars, Earth and perhaps elsewhere, a peak can push a body of air up past the point where it starts to form clouds, and on its leeward side chains of clouds can develop in similar manners. This is of course not always so. Rain clouds of any kind whose drops actually reach the ground are only found on Titan and Earth in this star system. Something like snow is more common, but is sometimes the atmosphere itself freezing. Hence when you look at the sky, you’re seeing clouds like those on countless billions (long scale) of worlds throughout the cosmos.

These processes and structures can be composed of less expected materials in other star systems. A particularly easy kind of planet to detect by the method of looking for light being dimmed by a large body passing frequently between us and the star is the “Hot Jupiter”. These are, as the name suggests, somewhat Jupiter-like planets, but differ from our own largest planet in that they orbit their primaries in a couple of days and are far hotter at their cloudtops than any planet’s surface in our own system. Consequently, although they too have clouds “like” ours, they’re actually made of substances like droplets of molten titanium or quartz, or perhaps crystals of the same. Meanwhile, circling the Sun and doubtless innumerable other stars further out than Earth, the converse situation exists, with volcanoes made substantially of water ice and erupting water instead of silicate, while the clouds are made of ice or water vapour instead. This is as extreme compared to a world like Enceladus, Titan or Pluto as the silicate clouds are to us.

Taking the comparison a bit more deeply, the water that erupts out of volcanoes in the outer system emerges from a mantle of flowing slush analogous in the same way to our own rocky mantle, which does flow but is not really fluid as we understand the term as it’s extremely viscuous, but just as far out moons hide internal water oceans beneath a superficial veneer of ice, though sometimes a very thick crust thereof, so does our home world secrete a deep ocean of rock. It’s easy for us to imagine that somewhere like Europa or Enceladus could be concealing a vast reservoir of sea water replete with its own version of fish because we are ourselves familiar with that from our own seas. Extending that to our own mantle, who are we to say that there are no “fish”, perhaps silicon-based, hundreds of kilometres beneath our feet? After all, the ocean of rock is hundreds of times larger than the ocean of water on our home world. This can only be speculation, at least right now, and it’s hard to imagine how it could become anything else. Maybe there is an extremely hot Earth-sized planet whose lava oceans do contain life forms, or maybe not, but we’re looking for “life as we know it” when the one thing we really do know about life elsewhere is that we know nothing of it, or even of its existence.

And perhaps we will never know. Clearly nothing we’re aware of now could rule out the presence of other life off Earth, because we have an example of life here, but although there are numerous reasons we could project onto the sky that might make it implausible, it’s entirely possible that we’ll simply never know if we’re alone in the Universe, and that might apply even if we embarked on an exploration of it. Even if our entire Galaxy proved to be lifeless apart from us, there might be no particular reason for it other than luck, and another galaxy, such as Andromeda, could have life, and if not that a different galaxy so many gigaparsecs from us that we’ll never know it exists. Right now there doesn’t seem to be any kind of mathematical or scientific argument which would be able to give us an answer to this question. It’s rather like the existence of God. You can be “theist”, believing that there is life elsewhere. You can be “atheist”, observing the Universe and the physical laws which decide what can be in it and deciding that life is just a fantastically improbable freak accident, thus committing yourself to the probability that terrestrial life is all there is. Or, you can be agnostic, and simply withhold an opinion on the matter, while holding out for the possibility that there is or is not on a kind of faith-like basis. It’s even possible that we will never know if there’s life within our own planet.

Getting back to precipitation, there is a line from the TV series ‘Wonder Woman’ which seemed highly dubious when I first heard it. A man from the future visits the late 1970s and remarks to her that there are planets made of diamond where a stick of wood would be a previous commodity. At the time I suppose I assumed that other planets were more like our own than they in fact are, because remarkably for such a soft and unscientific franchise as ‘Wonder Woman’, with the likes of disappearing handbags and invisible aircraft, this is in fact so, and you don’t even need to look outside our own star system to find such planets. Both our ice giants are probably so rich in diamonds that they’re as common as icebergs in the Arctic or hailstones on a spring day, and wood would naturally be unheard of. Wood is also associated with life of course, and we have no idea how specific it is to Earth. If it is, it’s like blue john, which only occurs in one place in our Solar System and probably for many light years further than that, in the Derbyshire Peak District.

Water has influenced the appearance of the Peak District in a couple of significant ways which give the area its distinctive character. One is through the erosion of potholes and other caverns and another is the various effects of glaciers, such as causing lakes to form by blocking rivers and the presence of isolated boulders a long way from their original locations. It isn’t clear what actually happened there in that respect during recent ice ages, but it seems that ice-related erosion and weathering relatively close to melting point where ice expands as its temperature falls is likely to be characteristic of Earth as an ongoing process rather than anywhere else in the system, although during certain relatively short-lived catastrophes this does seem to become significant. The difference here is that in many places the temperature has fluctuated around the range where this takes place, making it a dynamic and repetitive process.

Looking up, we may see Cynthia. I’ve been rather startled to find recently that for some reason flat Earthers perceive her as luminous! She looks like nothing so much as a ball of grey rock to me. A varied and beautiful one to be sure, but not luminous. This impression, though, is not confined to our satellite. The other planets in the system do in fact look like bright stars to the naked eye. Even so, there are noctilucent clouds, which are so high in our atmosphere that they reflect sunlight considerably later or earlier than sunset or sunrise. It’s simply that unexpectedly daylit items in the night look so bright by contrast that they’re practically luminous, but not literally so. It illustrates how much the human eye can adjust to light and darkness that Cynthia can appear to shine. Yes, there is moonlight. Also, the light from the white door in our bedroom reflects onto the blue-painted wall, almost bringing us back to Fauvism.

When Sarada became aware that I tended to get bogged down in details, she recommended a book to me which I very much enjoyed: ‘The Mezzanine’, by Nicholson Baker. Baker’s book, which can hardly be described as a novel, focusses on the minutiæ of the quotidian in a manner possibly reminiscent of «A la recherche du temps perdu». Whereas I find the latter unhealthily self-absorbed (though I haven’t read it), the former caught my attention and was easy to relate to. It has no real plot and has been described as having a “fierce attention to detail”. As a young adult, I used to write long descriptions which I couldn’t turn into stories. Fortunately, Baker has succeeded in getting a work using a similar approach published. Most of our experience, mine at least, consists of such thoughts and unfinished mental doodles. One difference is that ‘Mezzanine’ finishes these. The approach taken is somewhat reminiscent of a minor poetic movement of the late twentieth century called “Martian Poetry”.

Martian Poetry is a small and fairly transient subgenre of poetry whose most famous piece is Craig Raine’s ‘A Martian Sends A Postcard Home’. This can be found here. It can take a while to puzzle out, but refers to such things as books, telephones and sleeping together. It’s a series of riddles, but more than that. Published in 1979, it uses unusual metaphors to make everyday objects and experiences fresh and unusual. It’s a little like the real-life ‘Man Who Mistook His Wife For A Hat’ and it raises the question in my mind of who the narrator is. When I wrote the previous post, I realised I’d created a problem. I had no idea who the aliens describing Earth were and I had to come up with a semi-feasible model of their own world, anatomy and physiology before I could begin to portray our home planet. In particular, I had the alternatives of making their comfort temperature hotter or colder than ours, and chose colder because more of our own star system, and in fact the whole Universe, is colder than Earth’s surface rather than hotter. Once I’d done that, I had something I could relate to and a perspective from which to conceive of Earth as others see it. Craig Raine, unsurprisingly, doesn’t do that. We can, however, glean something about the narrator because of the metaphors used, which can be contradictory. For instance, he uses the word “caxtons” to describe books, which he sees as avian, multiwinged creatures. This is a spiky-sounding word with its C and X, and calls to mind a rustly, fluttering thing which one might imagine capable of flight, and certainly it confers that capacity to its reader’s mind, but calling it after the fifteenth century printer anchors it in human life, and even in England. Nor does Craine play fair with the reader when he later describes mist as making the world “bookish”. The problem Craine sets himself is that of not being able to make the narrator Martian enough, because that would seem to make the poem less comprehensible.

I tried fairly hard to find another example of a Martian poet, but all I could uncover was Christopher Reid’s ‘The Song Of Lunch’, and even then I was only able to see the Emma Thompson and Alan Rickman TV movie version. It has a somewhat similar quality but as the action, such as it is, proceeds, it injects elements of plot and tension into the story and is much more conventional. It can currently be viewed here.

What makes these different from my own perspective of seeing a fountain in the park and thinking of the plume on Io’s Tvashtar Patera is specificity. I’m looking at the world in a kind of Cartesian way. I see the parabolas described by the water and consider the similarity, which does make me view them afresh, but there are only specific and sparse details and the comparison is with a specific alien environment. This cognitive estrangement can, however, be broadened and make the whole world surreal. I can remember one guy describing the experience of going swimming as stripping naked, putting on a pair of turquoise pants and immersing himself in a bluish liquid in a large blue room with various other similarly-attired people, and this is indeed surreal, and is more general than the constrained and sporadic examples I’ve mentioned above.

Neurodiversity has sometimes been described as being on the wrong planet, and there’s a website, wrongplanet.net, with this name. But which planet is wrong? Maybe it’s this one. “We” who are neurodiverse might be on a planet which, as a whole, treats us badly and makes assumptions which the rest of us will never be able to guess. This planet could be morally wrong. However, that’s unfair. In fact it isn’t the planet which treats neurodiversity so much as Homo sapiens. And the planet we come from isn’t wrong either. It’s actually the same planet: a conjoined twin Earth with as much right to life as Neurotypical Earth.

That brings us to the Véronique Sanson «chanson» quoted above. The line from Kiki Dee’s English version of the song has always puzzled me – “I feel the rain fall on another planet”. It comes across as a complete non sequitur. Sarada says I’m overthinking it. The original makes more sense: I have undergone such a life-changing experience that I am sensitive to the whole Universe. Now I have a grandchild (and a teenage grand-niece as of the other day, incidentally, which makes me feel really old), and I’m not comparing the experience of considering the Solar System’s other worlds in their own right to losing one’s virginity, but yes I am. I haven’t undertaken a project as grand as the so-called “Grand Tour” because all I’ve done is sit in the living room and typed stuff about the likes of Enceladus, but even that relatively mild enterprise has changed the way I see the world, and we all know about the Overview Effect, so who knows what would await us out there culturally or psychologically if any of our species crossed the lunar orbit?

A Large Terrestrial Planet Orbiting A Yellow Dwarf

After an extensive sky survey covering the planetary systems of a wide range of mid- to high-mass long-lived stars, a number of interesting systems were identified. Although scientists have traditionally focussed on stars suitable for life, with some success, the decision was made to widen the parameters for consideration to larger and more luminous examples in order to prevent observer bias. In particular, a fairly large and hot star was located whose planetary atmospheres showed a number of interesting features. The star was named Sol.

Sol is on first examination not the ideal location for life-bearing worlds. The star itself is considerably more luminous, hotter and more short-lived than our own and there is a notable absence of planets in the habitable zone, occupied by asteroids in this system. Moreover, there is an unusual absence of any planets with the mass of Planet, and therefore moons such as our home world, where life can arise and evolve straightforwardly, are completely lacking. The problems with life arising in this system are multiple. The lifetime of the star is relatively short, the system inside the asteroid belt is above the boiling point of ammonia, which in any case tends to get broken down by the radiation.

In the inner system, there are a large number of moons, all of which are however not particularly hospitable to life. Although three of the four gas giants have large moons, only one has a substantial atmosphere and is too cold for life as we know it to thrive or even appear there. Even so, this proved to be the most hospitable environment and a base was established there from which to mount missions to the other worlds in the system. None of the moons were at all promising. However, just out of curiosity, it was suggested that we investigate the inner system, in spite of its presumed hostility to life.

The situation did not at first appear very promising. There was only one relatively large satellite and even it was too small to maintain an atmosphere. The fourth planet had two small asteroid-sized moons which were even less promising, and the inner two planets had none at all. Two of the planets were large, and of these the outer planet was the host for the single large satellite, although it was considerably smaller than Planet itself. The fourth planet is close to our own world in size but is less dense and has very little to no ammonia on its surface and a tenuous atmosphere incompatible with the existence of most liquids.

Although slightly less hostile than the second planet, the host planet attracted attention because of its rather unpromising moon. It was found that, most improbably, the moon was of such a size and distance from the planet that it would perfectly cover the planet’s star from some locations on the planet, a situation which may well be unique in our Galaxy. This attracted attention to the solid surface of said planet, henceforth referred to as Sol III.

Sol III is a large, hot and rocky planet with a highly corrosive atmosphere and a surface largely covered in an expanse of molten dihydrogen monoxide rock, a substance henceforth referred to by its systematic standard name of oxidane. Runaway exothermic chemical reactions periodically occur on the surface where the likes of thunderstorms and volcanic eruptions trigger destructive processes which it might be thought would completely transform the surface. However, it has been found that in many cases this reaction can be limited by the presence of the liquid oxidane, which prevents dioxygen and the compounds in question coming into contact. Although the atmosphere is mainly (di)nitrogen, over a fifth of it consists of free dioxygen at sea level, becoming ozone some distance above the surface. Although the moon shows captured rotation, Sol III does not, rotating once every 24 hours. This has the consequence of causing the molten rock to flood the margins of the isolated land promontories twice every rotation. Any organism able to survive the extreme heat of most of the solid planetary surface unfortunate enough to find itself in such a location would be swiftly boiled to death by such events. Even away from the lava fields, liquid rock often falls from the sky, so there is little respite elsewhere on the planet.

There are exceptions to these conditions. There is a small area on the west side of one of the southern land promontories where this precipitation rarely or never takes place and many other regions close to the equator where it’s a relatively uncommon event, and these areas are free from the rivers and other bodies which make conditions so hazardous. The liquid is also quite corrosive and somewhat acidic compared to ammonia and tends to eat away at the solid surface of the planet. There are clouds of vaporised rock higher in the atmosphere which sometimes reach ground level. Near the poles the situation is slightly more hospitable, since these areas stay below oxidane’s melting point, and near the south pole temperatures are comfortable through most of the planet’s orbit and relatively normal crystallised oxidane.

Surface gravity is about triple our own, which would make it difficult to tolerate for long, and immersion in liquid would be one strategy to enable us to survive for long periods on the surface Sol is bluer than our own sun, with the result that the landscape, seascape and items within it have a blue tinge. This particularly applies to the lava plains dominating the surface and the sky when free of cloud. The higher gravity also flattens the solid surface, most of which is below the level of the lava, reducing the relief still further.

Considering the oxidane as a simple bulk substitute for our own ammonia, the chief difference between Sol III and our home moon is that the majority of the world is covered by an interconnected body of water, into which streams and rivers tend to feed, unlike our system of independently interconnected lake networks. Its mineral nature is emphasised by the presence in solution of many minerals, partly due to the strongly solvent properties of the liquid. More than half the solid surface is in permanent darkness and only just above oxidane’s melting point, though still far above the levels compatible with life as we know it. Also common here is a manifestation of the even hotter interior of the planet, also found on land, where even the silicate minerals melt and flow like ammonia. The silicate volcanism of Sol III, though, is physically still quite similar to our own oxidane volcanism, except that the volcanoes produced tend to be flatter and have less steep sides.

Technical terms have had to have been invented for the surface features of the planet. The lava fields are referred to by the arcane classical term “ocean”, and the giant island promontories as “continents”. Although the ocean is a single entity, there are also lakes on the surface which are not linked to them. These tend to be purer oxidane because of the reduced volume and time available to dissolve the underlying rocks. The ocean itself is conceptually divided into four sub-oceans, referred to as “northern”, “western”, “eastern” and “southern”. Currents running along the last three also mean that there is in a sense a further ocean not separated by land from the others. There are six continents. A relatively hospitable one is situated in the southern polar region, where the temperatures remain low enough for practically the whole surface to be lava-free. The corrosive atmosphere and high gravity, of course, remain. Most of the surface from the northern coasts of the polar continent is molten although the smallest continent, referred to as “Southern” is relatively free of precipitation. There are then two triangular continents, both linked to northern ones, referred to as “West Triangle” and “East Triangle” . The larger one, East Triangle, has two large areas free of precipitation but like Southern is extremely hot. West Triangle has a small stretch with practically no precipitation. Adjoining East Triangle is the Great Continent of the northern hemisphere. This is the largest continent of all, and its northeastern region is again cool enough not to kill someone quickly. The same is true of the final continent to be mentioned, the Lesser Northern Continent, although this and the Great Continent become very hot nearer the equator.

The surface of the planet is young. Unsurprisingly, the oceans are in constant motion, but the oxidane also eats away at the solid surface over a much longer time scale, although the occasional catastrophe can make major changes very quickly. WInds are another significant erosive factor. Also, in a process not found on our home world, the surface as a whole is constantly remodelled over a period of millions of years and the continents move around, collide with each other forming island chains and mountain ranges and split apart. This is, however, a very slow process. One consequence of this along with the erosion is the near-absence of impact craters.

A paradox of Sol III is how such a hot planet with a highly reactive atmosphere can remain in a fairly stable state rather than all the dioxygen reacting with the surface rocks and being removed from the atmosphere. The solution to this is quite remarkable: there are two balanced biochemical processes, one combining oxidane and gaseous carbon dioxide into energy-storage compounds with the aid of stellar radiation which releases the toxic gas as a waste produce, and another which combines the energy-storage compounds with dioxygen and releases carbon dioxide. Things were not ever thus. The planet went through a stage early in its history at an equable temperature, though still higher than our home world, with a harmless and hospitable atmosphere. Then, a certain group of microbes developed a mutation causing them to release the poisonous gas and the pollution of the atmosphere killed much of the biosphere. Hence not only is there life on the planet, in profusion in fact, but it actually requires the extreme high temperatures, molten lava and toxic atmosphere to survive. Although there are a few less extreme environments on the surface free of oxygen, all life on the planet uses molten oxidane to survive. Only a very few species could survive at temperatures we would consider comfortable or even survivable, and at such temperatures they’re in a dormant state from which they can only emerge in conditions of extreme heat. There is no true overlap between conditions life on Sol III would find tolerable and our own definition of survivable conditions.

Leaving microbes aside, some of which have biochemistry a little closer to our own with the proviso that they don’t employ ammonia, the larger organisms on the surface fall into three categories, which are covered below. It might be thought that the high gravity would make a buoyant environment more suitable for life, and in fact there is indeed more life living within the oxidane than out of it, there is also plenty of life outside these conditions. Although land life on Sol III tends to be smaller and stockier than the kind we’re familiar with, it’s as diverse and widespread as it is on our home world. One difference is that our own life originates from three different stocks due to our independent lake networks, whereas all life on Sol III is related because it originated in the ocean, or at least spent a long time evolving there before becoming able to leave it and exploit other niches.

One form of macroscopic life tends to use a prominent green pigment to absorb red light from the star to drive a nutrition-synthesising process. Its reliance on red light may reveal how life on Sol III is at a disadvantage compared to life on worlds near to redder stars. It’s this process, known as photosynthesis, which was responsible for poisoning the planet and causing the extinction of most life forms earlier in its history. Most large organisms reliant directly on photosynthesis do not move much of their own volition and the terrestrial varieties often bear colourful genitals which attract motile organisms to bear their semen to other members of their species and fertilise their eggs.

Another form of life tends to be able to move of its own accord and survives by consuming the bodies of other, often living, organisms. Their anatomy and physiology is usually centred around their need to move dissolved gases around their bodies, which they often manage using a system of tubes and one or more pumps. Their reliance on dioxygen and need to remove carbon dioxide gas from their tissues necessitates that all of their bodies need to be in close contact with a respiratory fluid, and all of the larger organisms also have entire body systems to deal with gases, either dissolved in the water around them or present in the air. In the case of the dominant class of animals, as they are known, on the land, this has limited their size as they rely on tubes open to the atmosphere. Incredible though it may seem, most animals can’t survive more than a few minutes without a constant supply of dioxygen.

The third form of life forms a kind of bridge between living and non-living parts of the food chain. Like the photosynthesisers, these are largely sessile and immobile, and tend to live off a substrate consisting of the dead or diseased bodies of other organisms. They do not photosynthesise. Many of them consist of subterranean mats of fibres which produce occasional fruiting bodies above ground level. Some of them are also parasitic. Without this group of organisms, there would be an ever-increasing unusable biomasse which would eventually cause all advanced life on Sol III to grind to a halt.

Animal evolution on Sol III went in a somewhat surprising direction. Unusually, a particular kind of fluid-living animal developed a hard internal skeleton and its descendents were able to use it to aid their movement rather than the more usual arrangement of holding them in place. These have proliferated into a variety of forms, though they constitute a small minority of species on the planet and animals themselves occupy much less biomasse than the plants (the photosynthesisers). Of all these species, one rather large, by the standards of the planet, type has become dominant over the planet through a technology based initially on the use and control of the runaway oxidative reaction and the discovery of language, which is acoustic and mediated by means of the organs which evolved to exchange gases. Remarkably, in spite of the intense gravitational field, these animals are able to achieve an erect bipedal gait.

It should be noted that the pace of animal life on Sol III tends to be very frenetic. This seems to be due to the high temperature and the employment of dioxygen as a means of releasing chemical energy. This hyperactivity doesn’t apply to plants to the same extent. It’s all the more so for those animals whose bodies rely on their own heat to drive their metabolism, and unsurprisingly this includes the technological species. Dormancy is a less significant phase of life for many animals living on the planet, partly because the years are shorter and in many parts of the world the seasons are less extreme. However, many species do become dormant on a diurnal basis for a considerable fraction of the planet’s rotation period, often when it faces away from the star, and depriving them of it for surprisingly short intervals leads to increasing mental derangement. The need of such organisms for food, oxidane and their respiratory gas is quite extreme compared to our own. This constitutes a barrier to space travel, as it means they are unlikely to be able to survive interstellar space voyages as easily as we can. This may not be a bad thing because there is a tendency for some members of the species to be quite violent, but this is also likely to be self-limiting. However, it’s probably better not to speculate too much about this aspect of their nature without more data.

One major lesson to learn from the complex life present on Sol III is that we may have restricted views on what constitutes an hospitable environment for the advent and evolution of advanced life forms. Before this discovery, the proposal that a sophisticated biosphere could exist on a planet two-thirds covered in molten rock with a dense caustic atmosphere capable of eating through metal, with a high gravitational field and temperatures far above boiling point over most of its surface, circling an ageing Sun much hotter and more massive than our own would have seemed ridiculous to all. These life forms can not only tolerate living with acidic molten rock in an aggressively reactive atmosphere but have evolved in tandem with it to the extent that depriving them of the gas for more than a few minutes is uniformly fatal and they need a continual intake of liquefied dihydrogen monoxide to survive more than a couple of rotations of their home world. Who knows what the inhabitants of Sol III might consider suitable conditions for life given their own extreme circumstances?

Any resemblance to Arthur C Clarke’s ‘Report On Planet Three’ is not entirely coincidental.

Are We Out In Dullsville Now?

If you go back to where I started this series properly, you’ll find that I produced a post, whose name and location I’ve currently forgotten, introducing the Solar System from the outside in. I’ve now returned to the outermost part of the system except for the Oort Cloud, and I ask myself, are these outer reaches really dull? Well, they are in a literal sense of course, in that the Sun is pretty dim at this distance, but the wide separation, small size and low temperature of worlds, if that’s the right word for them, combined with the facts that nothing has ever visited them and that they’re hard to detect, means that they might also be exceedingly boring. I can imagine people travelling to them who want to get seriously away from it all, and from other people. In fact, there’s a scene in an Iain M Banks novel about someone who has done precisely that. I think it’s ‘Excession’.

There’s a lot going on in the regions near the Sun, and I use “near” quite loosely as I intend for it to apply to Jupiter and Saturn, the latter being well over a milliard kilometres from it. Incidentally, why is it we get stuck at kilometres? I’ve just fished out an obscure English word to describe a distance which could easily be referred to as a terametre, and yet we never say that. The further out one goes, the less is happening, with the occasional exception such as Triton’s liquid nitrogen geysers and the mysterious brightness of the surface of Eris. Average distances between worlds increase, temperatures plummet and the Sun looks ever dimmer. That said, it’s still possible, for example, to imagine a world so cold that it has oceans of helium II which crawl over its surface and climb mountains, or outcrops of superconducting alloys which generate incredibly powerful magnetic fields. I don’t know if either of those things are possible, because the 3K background temperature of the Universe might rule them out and helium only becomes superfluid at 2.17K, but there have always been surprises. Few people would’ve guessed that Neptune has winds which blow faster than the sea level speed of sound, for instance. Perhaps high winds on a very cold planet would cool it below the temperature of deep space.

Considering the history of the Universe, a frantic and hyper beginning slows down continually, through the current stelliferous era and other less and less eventful stretches of time until basically nothing is happening. Space is rather like this too. Not a lot goes on in the Oort Cloud.

Even so, there is stuff out there. For instance, there’s a planetoid nicknamed FarFarOut, which is 132 AU from the Sun. Also known as 2018 AG₃₇, FarFarOut is about four hundred kilometres across, which means it could be round. It actually swings round to being only 27 AU, closer than Hamlet. It takes 718 years to orbit and at its maximum distance of 132.7 AU the Sun is almost 18 000 times dimmer than from here. There’s also 2019 EU₅, which averages 1 380 AU from it and has a maximum distance of 2 714 AU. These figures are highly uncertain, but if the aphelion is correct (it could be considerably greater or less), sunlight at such a distance is finally weaker than our moonlight and the planetoid takes fifty-one thousand years to orbit the Sun at a mean velocity of about eight hundred metres per second. With such planetoids, it becomes difficult to judge their actual trajectories because they move so slowly and haven’t been observed for long.

There are now five human-built spacecraft out there: Pioneers 10 and 11, Voyagers 1 and 2 and New Horizons, the last being the newcomer, only launched in 2006. Voyager 1 was manœuvred out of the ecliptic so it could get a good view of Titan, and is therefore heading out into the scattered disc rather than the Kuiper belt. It’s 153 AU from the Sun at the moment. Voyager 2 is 130 AU out. Both were launched in 1977. The Pioneer probes have been going for rather longer but are actually closer, at 129 and 108, but they’re all now over twice as far away as Pluto ever gets. New Horizons is a mere 50 AU from the Sun right now. Now a viable claim is made that the Voyager and Pioneer probes are now in interstellar space because the pressure of the solar wind is weaker than the ambient “flow” (I suppose) of charged particles between the stars, but there are still planetoids orbiting out there, even ones which never dip into the volume inside the heliosheath. Isaac Asimov’s novel ‘The Currents Of Space’, though its science is out of date, uses the idea of similar flows as an important plot point, so this is one possible way in which the outer part of the Solar System might not be boring. Processes taking place within the heliosheath which influence planets, asteroids, moons and so forth would not operate beyond it. For instance, any magnetospheres which exist out there would not be thrown into asymmetry by the solar wind, and larger and denser atmospheres could exist out there, although the only elements able to maintain a gaseous state at such temperatures would be hydrogen and helium, and in fact ultimately helium. It also means the useful isotopes found in lunar regolith would be absent from many trans Neptunian objects and this reduces the utility of mining for them.

There are a dozen known planets, dwarf planets by the IAU definition of course, which reach 150 AU or more from the Sun. This is one motivation for not calling them planets. If they were, they’d now outnumber the major planets. The same is, though, also true of asteroids and centaurs, and asteroids were simply called “minor planets”. The whole thing seems a bit silly and solves a “problem” which had in any case already been sorted when such concepts as major and minor planets, or planetoids, were invented to address the issue after the discovery of Ceres, in the early nineteenth century CE. Right: I’m going to resolve not to go on about this for the rest of this post as I’m sure it’s getting old. These objects include Haumea, Quaoar, Eris, Sedna, Makemake, Albion, Gonggong, Pluto itself, Varuna, Arrokoth, Arawn, Chaos, Ixion and Typhon. Others are also named, but most don’t come up much in discussions or news, and most of them have provisional designations. To be honest, some of them just stick in my mind because of their names, particularly Quaoar but also Makemake and Gonggong. FarFarOut has a predecessor which isn’t so far out called FarOut. There are two zones: the Kuiper belt, which consists of objects orbiting near the plane of the inner system, and the Scattered Disc, comprising objects whose orbits are more tilted. The second category developed because of the gravitational influence of the outer planets, although it occurs to me that this might also be the region where the Sun’s influence and the traces of the solar nebula become less relevant to them. There is also a third region, the Oort Cloud, which is in really deep space beyond either of the others, whence some comets originate, and extends for over a light year in every direction. TNOs are also distinguished by colour (Eris springs to mind but that’s a special case as far as I know). They’re either steely blue or bright red. A classification kind of cutting across this are the poorly-named “hot” and “cold” categories. Cold TNOs orbit close to the ecliptic and are usually red. Hot TNOs have tilted orbits and range between the two colours, which means that the red ones are the “cold” ones.

By Pablo Carlos Budassi – Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=94143935

One of the weirdest known trans Neptunian objects is Haumea, illustrated above. This has three remarkable features. It has a ring, two moons and is ellipsoidal but far from spherical. It counts as a dwarf planet. Its unusual shape is called a Jacobi ellipsoid, and is rather surprising. It intuitively makes sense that a rapidly-spinning body would be thrown outwards at its equator and therefore assume a kind of tangerine shape, or perhaps even a discus shape, as seen clearly with Jupiter and Saturn but also with most major planets including Earth to some extent. Venus and Mars are somewhat different, the former being almost spherical and the latter having a more egg-shaped form due to the Tharsis bulge. This more intuitive shape, an oblate spheroid, is quite common and the torus is another quite remarkable stable shape which, however, is hard to envisage actually forming in the first place. There is a notorious (to Sarada and me) pebble classification system called Zingg (two G’s), which divides them into spheres, discs, rods and blades according to their X, Y and Z axes. This used to be a source of joy to us due to its apparent obscurity, but has its uses, and Haumea counts as a blade. Each axis is markèdly different to the other two. Lagrange, who discovered the points of gravitational equilibrium around pairs of masses responsible, for instance, for the trojan asteroids in the orbits of several major planets and the trojan moons in the Saturnian system, held that the only stable shape for a rapidly rotating body of a certain size was the oblate spheroid, but counter-intuitively, this turns out to be wrong. This is the gateway to a whole branch of geometry involving ellipsoids.

Haumea’s axial dimensions are 2 322 × 1 704 × 1 138 kilometres. It spins once every three hours and fifty-five minutes, which is particularly high considering its size. Comparing it to Pluto, for example, that planet takes six and a half days to rotate and has a diameter of 2 377 kilometres. Not only is Haumea considerably smaller and less massive but it also spins three dozen times faster, causing a much stronger centrifugal effect. I have to admit that not only is it entirely unclear to me why Haumea is this shape beyond the simply fact that it’s spinning really fast and has thereby had projections drawn out from it, but also I can’t understand the maths behind it. If this can happen once, maybe there are larger planets out there somewhere with the same shape, maybe even Earth-sized ones. It seems unlikely, at least because a larger object would tend to be more spherical, although there could be other reasons why it might happen such as a nearby massive body pulling it out of shape. Haumea was probably hit some time in the past by something which sent it spinning wildly. It also isn’t clear that it’s reached hydrostatic equilibrium although it’s very large for a solid object if it hasn’t.

Haumea is the Hawaiian goddess of fertility and childbirth. The planet’s moons are named after her daughters, Hi‘iaka and Namaka. It’s thought to be rocky with a surface layer of water ice and seems to have a red crater near one of the geometric poles (i.e. on the equator). I’m guessing the reddish colour is due to tholins. Haumea seems denser than most other Kuiper belt objects, including Pluto, and may be as dense as Mars or Cynthia. It has crystalline water ice on its surface even though its temperature ought to cause the ice to become glassy. There may also be clay on the surface, and cyanides of various kinds. Hence the very surface would often be highly poisonous to ærobic life forms, including humans. There is no methane, suggesting that it was boiled away in the heat of impact.

The ring spins once every twelve hours, in other words a third as fast as the planet. The moons are small and probably result from the collision. Another thing which probably results from the collision is the Haumea family. In other parts of the Solar System, there are various families of objects, for instance the Vesta family, which consists of Vesta plus the asteroids which have been chipped off it, including some meteorites which have arrived on Earth. The Haumea family is the only identified group of objects beyond Neptune, and originates from the collision. They’re all water-ice at the surface and are fairly bright. Some may be up to seven hundred kilometres in diameter and count as dwarf planets in their own right. They average between forty-one and forty-four AU from the Sun. One of them seems to be in the family but is red.

Haumea itself is 43 AU from the Sun on average and has an orbital eccentricity of a little under 0.2. It takes 283 years to traverse this orbit, so it isn’t enormously further away than Pluto and in fact it gets closer to the Sun than Pluto does.

Another name which sticks in the mind belongs to the dwarf planet Sedna. This is one of the reddest known objects in the system and is also tied with Ceres in being the largest moonless dwarf planet. Sedna is one of those planets which makes me wonder whether it’s one of many undiscovered ones, because it was discovered due to happening to be almost as close as it gets to the Sun at 76 AU. Even that distance is almost twice Pluto’s. It takes 11 400 years to orbit the Sun and gets out to five and a half light days from it. The last time it was there, there were mammoths on this planet and the pyramids had yet to be built. It’s around a thousand kilometres in diameter, like Ceres. It’s named after the Inuit goddess of the sea and its denizens. The extremely elongated orbit, which has an eccentricity of almost 0.85, could be explained by the presence of an extremely distant and large planet. It’s part of a class (as opposed to a “family”, as in the Haumea family) of objects whose perihelia are greater than 50 AU and mean distances over 150 AU from the Sun. These orbits have an eccentricity of around 0.8, so although that’s the definition, in actual fact they’re considerably more elliptical. It’s been established that there are no large planets in the system beyond Pluto to a considerable distance, although there is the question of a missing ice dwarf. That would, however, not be detectable by current methods and wouldn’t explain the sednoid bunching of orbits. It’s also been suggested that the sednoids move thus because they were influenced by nearby stars back when the Sun was young and part of a cluster of baby stars. There are occasional stars which seem to be almost twins of the Sun due to similar proportions of heavier elements (often referred to in astrophysics as “metals”), suggesting that they were once our companions. Alternatively, they may have been captured from those stars early on in the history of the system. The other two objects falling into this category are Leleakuhonua and 2012 VP₁₁₃.

As well as the usual tholins, Sedna is covered in frozen nitrogen and methane, which is present generally but absent from Haumea, probably due to the collision. Its orbit looks like this to scale:

By Tomruen – Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=60453344

There may be amorphous carbon on the surface. Unfortunately the term “amorphous carbon” is ambiguous as it can mean charcoal- or soot-like carbon, which in fact consists of graphite sheets haphazardly arranged, or it can literally mean amorphous, i.e. glass-like, carbon, which might have special properties such as being a high-temperature superconductor and being harder than diamond. I suspect they mean the former – just a load of boring old black gunk like you might dig out of a coal mine.

Sedna is special because it isn’t. It’s probably an example of a very numerous class of objects orbiting way out beyond the influence of Neptune in the Oort Cloud. We happen to know it’s there but there are likely to be many, many more examples way outnumbering the objects known in the inner system whose orbits haven’t so far allowed us to detect them. That said, the presence of tholins is related to the influence of solar radiation so it might not be typical of them.

Another planetoid is Arrokoth, unique in being the only trans-Neptunian object other than Pluto-Charon and their moons to have been visited by a space probe, New Horizons. It was nicknamed Ultima Thule, but this was later deprecated due to the association with Nazi occultism. It was actually named in a Pamunkey ceremony. The common “dumb bell” appearance shared by two of Pluto’s moons, some comets and other objects is also seen here. It’s thirty-six kilometres long altogether but consists of two smaller fused planetesimals, fifteen and twenty-two kilometres in length. Planetesimals are the bricks which make up planets and moons, and have never been seen in their raw form before. If a twenty-kilometre object is typical, Earth would be made up initially of over a hundred million of them, having long since melted together and lost their identities. There are interesting substances on its surface, including methanol, hydrogen cyanide and probably formaldehyde-based compounds and complex macromolecules somewhat similar to those found in living things. The basin in the foreground, which is probably a crater, is a bit less than seven kilometres across and called Sky. The axis of rotation passes through the centre of the dumb bell.

Arrokoth is a “cubewano”. These are named after their first discovered member, 1992 QB₁. Also known as “classical Kuiper Belt objects”, cubewanos are often in almost circular orbits less than 30°from the plane of the Solar System, but are also often not. They have years between 248 and 330 times ours, the lower limit being defined by the plutinos with their sidereal periods close to Pluto’s. I’ve mentioned them above. They’re distinctive in not being particularly distant (relatively) and also not having orbits connected to Neptune’s.

Quaoar is a particularly large cubewano. Its name is from an indigeous people called the Tongva in Southwestern North America, although for a time it was called “Object X” as a reference to Planet X and because its nature was unknown. You can see the planetary definition crisis developing here, as it was discovered in 2002. It was first imaged in 1954, but like many other bodies went unnoticed for many years. It takes 289 years to orbit the Sun and is 43 AU from it. It seems quite dark, suggesting that it’s lost ice from its surface, which has a temperature of -231°C. It has a moon to keep it company, like many other trans-Neptunian objects. The diameter is around 1 100 kilometres.

Previously, the largest known TNO was Varuna, discovered in 2000. This may also be a “blade”-shaped planet like Haumea, and is just barely beyond Pluto’s average distance from the Sun at 42.7 AU, taking 279 years to orbit. It seems to be less dense than water and its average diameter was recently estimated at 654 kilometres. It takes six and a half hours to rotate on its axis.

I feel that this series is now drawing to a close. However, there are many objects I haven’t considered, such as the Neptune trojans, the possibility of Nemesis and the question of what large objects may be swimming out there in the depths of the Oort Cloud. There is also one planet I haven’t given its own post. It’s a small blue-green planet, third from the Sun, and will form the subject of my next post.

Pluto’s Kingdom

In the furore following from Pluto’s demotion after Eris’s discovery, a few people argued that Pluto of all places deserved to be called a planet because it had a moon. In fact it has at least five: Charon, Kerberos, Hydra, Nix and Styx, not in that order. It certainly seems to make sense that if a world is hefty enough to have its own companions, it ought to count as a planet, but in fact that isn’t how it works, and there are actually a couple of reasons why having moons almost makes a world less planet-like, if by “planet” you mean a solid or fluid spheroidal body with a relatively strong gravitational pull.

Only two of the universally accepted major planets have no companions: Mercury and Venus. These are notably the two next to the Sun, so the reason may be that they lack the gravitational “oomph” to maintain them. Matter circling either wouldn’t have to be very far out before it felt the Sun’s pull more strongly than the planets’. That said, both of them have respectable gravitas of their own and are far more than just a bunch of rocks loosely bound together. This last is the point really. A small object is less able to hold itself together and is therefore more likely to be a collection of stones or chunks of other matter, highly porous and riddled with caves and liable to lose some of itself or not accumulate nearby bits of matter in the first place. Therefore, in a way, if a body has a few moons, this could be more a sign of it not being a proper planet rather than the other way round. The other reason is basically the same but proceeding from the other end. Many Kuiper Belt and scattered disc objects are binary, and quite possibly more than binary. The same is true to a lesser extent of the asteroids. Being binary is therefore a characteristic of agglomerations of matter which are too small to hold together, but confusingly, having moons is also a characteristic of large planets able to pull loads of stuff towards them which is either already in clumps or forms into planet-like worlds in their own right. Hence Pluto having five moons, one of which is very large indeed compared to the planet (yes, planet) itself, doesn’t count towards its possible planethood.

All this aside, Charon is so large that if it orbited alone it would definitely count as a planet, at least if Pluto does. Earth is notorious for having an unusually large moon, if moon it be, of an eighty-first of its density. Charon far outdoes this, and in doing so consequently outdoes all the other planets in this respect, whose moons are generally well under a thousandth of their mass. Charon’s mass is a little under an eighth of Pluto’s, which is deceptively small as it should be remembered that the diameter relates to the cube root of this figure. After all, Cynthia is a large disc in our sky because it’s a quarter of Earth’s diameter, not 1/81. If the ratio applied to Cynthia and Earth, the former would be considerably larger than Mars, and it might even be habitable, which raises the question of whether such double habitable planets exist out there somewhere. Charon is 1212 kilometres in diameter. Cynthia, like many moons, always shows the same face to us, and the same is true of Charon and Pluto, but in their case the situation is mutual. Both worlds face each other at all times.

I’ve allowed Charon to be overshadowed by Pluto in my own mind, and know relatively little about it. The story of its discovery and naming is quite remarkable. The mythological figure Charon is of course the entity who ferries the souls of the dead across the River Styx into the Underworld, and Pluto being king of the aforementioned domain, one might fancy that the motivation for calling the moon that was clear. However, this is not in fact so. The man who discovered Charon, James W. Christy, actually named it after his wife Charlene Mary, whom he calls Char, and had no idea that the Ferryman was called that too. This gives me pause for thought, because it doesn’t seem to work like one would expect it to naturalistically. It’s reminiscent of the fact that before Saturn was believed to have rings, saturnine herbs were those which had prominent rings, and it’s almost as if the names of celestial bodies are “out there” waiting to be discovered rather than invented, like the non-existent American states of Jefferson and Superior. I won’t dwell too long on this here, but a similar phenomenon is manifested in western astrology where hypothetical planets have been used which have turned out to be real, particularly Pluto.

On 22nd June 1978, Christy noticed that his image of Pluto was not circular, and also that it changed shape on a regular, predictable basis:

Pluto appeared to have a lump on its side which appeared and disappeared. Since the planet is far too big to be irregular, it was correctly concluded correctly that it has a moon, and that that moon takes almost six and a half days to orbit Pluto, or rather, that the two of them take that long to orbit each other. Of all moons and planets in the system, other than small irregular ones, Pluto and Charon are respectively the first and second largest worlds in their companion’s skies, even larger than the Sun in Mercury’s sky (which actually isn’t that large though). Due to captured rotation, that’s also the day length for both Pluto and Charon, and it makes Pluto the only planet to have captured rotation with its satellite, to the extent that it actually counts as a planet, not because of the IAU but because it’s binary and almost orbits Charon rather than the other way round. Axial inclination can also be guessed at fairly reliably with this because the two are likely to circle over each others’ equators, and it’s 57°, exceeding 45° and leading to different variations in day length and the like for the two. Any tilt over 45° involves a peculiar set of circumstances where the polar circles are closer to the equator than the tropics are, though at such a distance from the Sun it’s questionable whether it makes much difference. One thing which definitely does make a difference on Pluto is the atmosphere snowing onto the surface in the autumn and evaporating again in the spring, bearing in mind that the dates for these are more than a dozen decades apart. Speaking of dates, there are 14 205½ Charonian (or Plutonian) days in their year.

The two share many characteristics. Some of these are also shared with Triton, which is closer to Pluto in size and mass than Charon is, but the conditions on the two are even more similar because of their gravitational influence on each other and being the same distance from the Sun, having the same axial tilt and day length and so forth. It’s actually slightly awkward to talk about Charon separately from Pluto, but I’ve written quite a bit about the latter already and don’t want to go over it again. New Horizons managed to take photos of the two together, like this:

This picture is a bit misleading, as it’s effectively taken through a telephoto lens. It wouldn’t be possible to see this similarity near either world because the two are almost 20 000 kilometres apart and Charon is considerably smaller than Pluto even though they are closer in size than any other planet-moon combination. Even so, Charon is notably duller and has a reddish cap over its north polar region, whereas Pluto’s is closer to its equator. This red substance is, however, the same, and seems to have been shed from Pluto and deposited on Charon. Unsurprisingly, it consists of tholins, which are as I’ve said before an organic mixture of dark red tarry stuff which reminds me of the deposits made by herbal tinctures, partly because they actually are quite similar. Tannins in particular spring to mind. To repeat myself from elsewhere on this blog, tholins are the alternative route taken in the Universe by organic chemistry to organic life. The question of how often organic chemistry becomes biochemistry is another question, but there are clearly countless examples of tholins in the Universe judging by how many there are orbiting the Sun. Methane is also deposited on the surface from Pluto. Before any of the stuff gets there, though, it’s been part of Pluto’s atmosphere, and is therefore deposited faster near perihelion. Also, we finally get an answer to why trailing hemispheres are more heavily coated than leading ones: it’s because of gravity. Trailing hemispheres simply bear the brunt of falling material because the material has fallen further by then. The north cap is called Mordor Macula, “macula” meaning “spot”, as in “immaculate” – “spotless”.

Unlike Pluto, whose surface is largely solid nitrogen, Charon’s surface away from the tholin cap is mainly water ice but there are also patches of ammonia hydrates. Also unlike Pluto, there is effectively no atmosphere, so the snowing and sublimating processes on that planet don’t occur here. The south pole is also rather dark, but the north is darker. Although Charon doesn’t have a persistent atmosphere, substances on its surface do sublimate, becoming gas. It’s just that its gravity isn’t strong enough to hold on to any of them. The southern polar region was actually imaged with the help of “plutoshine”, as it was night time there when New Horizons visited, so image processing involved removing the tint of Pluto’s light to restore it to how it would’ve looked if sunlit.

Charon does actually seem to be geologically active, with geysers similar to those on Triton, shedding water ice and ammonia nitrate. This must’ve happened last less than thirty millennia ago, probably a lot less, because the ice deposits are still crystalline and haven’t changed to the glassy form expected after such a long period of time. The different composition of the geyser plumes also means that the moon is different beneath the surface and has geological layers, which was previously controversial as it is quite small. It’s likely that the moon is geologically active due to Pluto raising tides within it, a possibly mutual process, which raises the question of whether there’s substantial heating and an internal water ocean, which it’s becoming apparent is very common in the Universe. Scientists believe that in the distant geological past, it did indeed have an ocean within it but that this froze and expanded, leading to the formation of the enormous canyons visible on its surface in the image at the top of this blog post. This is one way in which water, as a geologically significant compound, behaves differently and leads to different land forms than other substances which melt and freeze. On Earth, water is currently not often a geologically significant “rock”, except at high altitudes and within the polar circles. Beyond the frost line of the Solar System, it often is, and unlike the other liquids, which are often gaseous at Earth-like temperatures, it expands on freezing, leading to geology very unlike ours. Although there are some other substances which expand on freezing, such as bismuth and gallium, they don’t generally occur in bulk. In the case of Charon, water ice is a major and significant mineral which contributes to the landscape and interior in a way something like silicate or carbonate rock does on or in Earth.

More precisely, the reason for those canyons is that as the interior of the moon froze, it expanded and fractured the surface, leading to the formation of a number of features referred to as “chasmata” – “chasms”. These include Tardis, Serenity, Nostromo, Caleuche, Mandjet, Argo and Macross. Many of these have a rather obvious naming scheme, which is fun. Caleuche, which is named after a mythical boat which sails the coast of Chile collecting the souls of the dead, is a Y-shaped canyon thirteen kilometres deep, among the deepest chasmata in the system. Mandjet is thirty kilometres wide, four kilometres deep and 385 kilometres long. Serenity is two hundred kilometres long as a chasma but runs an additional two hundred as an unpaired escarpment. All of these chasmata run around the moon’s equator, separating the northern Oz Terra from the southern Vulcan Planum, which is named after Spock’s planet. Oz is a kilometre higher than Vulcan over its whole surface. Both Oz and Vulcan extend across into the portion of the moon which was dark when New Horizons got there, but it seems likely that each occupies an entire hemisphere. Vulcan is less heavily cratered, suggesting that there’s recently (relatively) been geological activity there which has erased them by remodelling the surface. However, there are some craters and also central mountains, including Kirk and Kubrick. Spock, Sulu and Uhura are also represented thus, as well as Clarke (Arthur C Clarke). The entire area seems to have been covered by a large flow of liquid over the entire hemisphere, probably water.

Other craters include Vader, Pirx, Alice, Organa, Dorothy, Nemo, Skywalker, Ripley, Revati, Sadko, Nasredin, Cora and Kaguya-Hime. I do wonder how people whose religion includes some of these figures feel about the avowèdly fictional characters represented here, but perhaps the day will come when the Vulcan and Jedi world views become official religions too, if they haven’t already. There is another macula, Gallifrey, through whose middle Tardis runs. This means, oddly, that the confusion the Bi-Al Medical Foundation receptionist shows in the ‘Doctor Who’ adventure ‘The Invisible Enemy’ could be explained in a fangirlish way by the presence of this feature, which creates an Ontological Paradox similar to the one created by K-9’s motherboard, introduced in the same episode.

That, then, is Charon, which deserves considerable attention as the largest and best-known of Pluto’s moons. However, there are four more to be covered, and this raises a question: how do they orbit? All other known satellite systems with more than two members consist of a relatively large planet and a number of much smaller moons, and although the orbital dynamics can be somewhat peculiar, such as coörbital moons regularly swapping positions, Pluto-Charon is a different matter. There are two relatively similar masses and other moons in the immediate vicinity. It was calculated at one point that there could be stable orbits in such a situation if an object was at least 3.5 times closer to one mass than the other or if it was at least 3.5 times the maximum separation between the pair, and there are also improbable but stable orbits of various kinds between them such as a figure of eight. Ternary star systems usually have two close companions and a third, much more distant one: this is true, for example, of the Centauri system, where Proxima is much further away than A and B are from each other. The Pluto-Charon system is unique as far as is known in the Solar System in this respect.

Where, then, are the other moons?

This is an image taken by the Hubble Space Telescope three years before New Horizons reached Pluto, and was used to plan the mission. It’s notable that Charon and Pluto actually look fainter in this image than Hydra and Nix, or at least smaller. Styx doesn’t seem to be far away enough to maintain its trajectory. This picture shows that the moons are outside the Pluto-Charon region, separated by a small gap but all relatively close to each other, in an arrangement which reminds me slightly of the TRAPPIST-1 system where several planets are within the habitable zone. They don’t seem to be spaced any way like the Titius-Bode Series and although there is a space between the inner two and the rest, the relative distances of the others are not like those of ternary stars. It also raises two questions in my mind: is this similar to how planetary systems might be arranged around binary stars? Also, is this where Earth’s other moons would be if we had any?

There’s a further surprise. At least two of them are merged double moons themselves, namely Hydra and Kerberos. Going off on a tangent for a moment, bearing in mind that scientists now have sufficient reliable information to establish that two of the small moons of Pluto are former double moons, what the heck do flat Earthers and people who believe, and I quote, “space is fake” think is going on here? Why would NASA, other space agencies and the global astronomical community bother to put in that kind of detail about an entirely bogus cosmos? On the other hand, it is also true that esoteric blind alleys have been known to become highly elaborate, so maybe they think it’s along those lines. Also, fictional universes can be very intricate too. It just strikes me as highly implausible that something like this would be made up and makes me wonder about how flat Earthers think.

Anyway. . .

Hydra and Kerberos are former double moons, and this is evident from their shapes. This is Hydra:

This shape is similar to the comet being studied by the Rosetta probe, and in the comet’s case it’s thought to result from the merging of two bodies. This is that comet, known as 67P:

In the comet’s case, it’s been suggested that the shape results from the heat of the Sun eroding the nucleus. However, each lobe has concentric strata, suggesting that it was originally two bodies which got stuck together. Were it only one, it would have layers indicating a former, more regular form. Hydra is fifty-one kilometres long. Like all the small moons, Hydra is shiny with water ice, and is the outermost moon at a distance of 64 738 kilometres from the barycentre, which is outside Pluto. It’s probably receded from Pluto-Charon due to tidal forces. The name is a bit unusual and sticks out because it isn’t named after a humanoid mythological figure, and this principle also applies to the next moon in.

Which is Kerberos, named after the four-headed (the snake forming the tail has a head) guard dog of the Greek Underworld. Isaac Asimov once suggested that the tenth planet should be called Cerberus so that a mission approaching the Solar System from the great beyond would encounter the system’s guard dog first. To that end, it makes more sense that Hydra be called Kerberos and since the latter was already known to be closer to Pluto than Hydra when it was discovered, its name lacks elegance in a way. There are no good images of the moon:

This image gives the impression that the moon has done something naughty and needs to have its identity protected, but it can again be seen to have two lobes, suggesting again that it’s the result of the collision of two former moons. The two-lobed “dumb bell” appearance is quite common and approached by orbit-swapping moon pairs of moons near other planets. It’s about nineteen kilometres long and averages 57 783 kilometres from the barycentre. This figure combined with Hydra’s gives some indication of how close together the outer moons are, as these are the two outermost and there’s a highly unstable region close to Pluto-Charon, so there isn’t much space between them for moons to exist. Kerberos was named after an online poll and was not the most popular choice, and it’s spelt that way because there’s already an asteroid called Cerberus. The final choice was made by the IAU. Hmmm.

The next moon in, Nix, also has a story behind its name, which has again been re-spelt. Nyx is the Greek goddess of night, but since there was already an asteroid with that name, it became Nix in Pluto’s case, which is the Coptic spelling: “Ⲛⲓⲝ”. There’s actually a pretty good image of Nix from New Horizons:

To me, the brown smudge closest to the camera, which is eighteen kilometres across, looks like tholins, and there are also white bits which I imagine are water ice. Nix is almost exactly fifty kilometres long. Like all the smaller moons, Nix doesn’t have captured rotation but tumbles, so all these four moons have no north or south in the rotational sense.

The innermost small Plutonian moon is Styx, and if you thought Kerberos had a poor image, just look at this:

It can be conjectured to be elongated like Nix and is the dimmest known object in the Solar System at a magnitude of 27. That is, it’s as dim compared to a star like Vega as Vega itself is to the Sun, from Earth of course. I’m a little surprised by this because I would’ve thought Adonis, for example, would be dimmer, since that asteroid is only two hundred metres across, but that’s actually hundreds of times brighter at 18. Styx is a sensible name because crossing its orbit brings one into Pluto’s kingdom, more or less, and it’s also the next moon out from Charon. Styx’s longest dimension is sixteen kilometres, so it’s smaller than the oft-employed Isle Of Wight yardstick. It takes twenty days to orbit the barycentre, 42 656 kilometres away.

All of the outer moons have orbital resonances with each other. Styx is almost in harmony with Pluto-Charon too. This brings up the question of their probable mode of formation. All are grey, unlike Pluto, and are thought to have been formed in a similar manner to Cynthia, with an impact from a large body kicking up débris from the surface which later fell into orbits and coalesced. These orbits would’ve been closer to Pluto than they currently are. Interestingly, three of the moons were named in 1940 in a SF story by Peter Hamilton: Cerberus (sic), Charon and Styx. Their orbits are fairly chaotic and not fixed over millions of years.

Next time I’ll turn to the other largish worlds beyond Neptune. We’re really approaching the end now. Thank you for your patience.

Hail Eris!

It used to be so simple, concordant and ordered. There were nine planets: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Hamlet, Neptune and Pluto. Of course, on the whole people didn’t call the one between Saturn and Neptune by that name but my patience with puerile jokes is finite and I actually think making one of them a joke just because it has a ridiculous name does it and science a disservice. My Very Eager Mother Just Served Us Nine Pizzas. Many Volcanoes Erupt Mulberry Jam Sandwiches Under Normal Pressure, which is the one I remember. Those mnemonics are actually quite odd, not just because they’re memorable sentences – it’d be odd for a mnemonic not to be memorable – but because I don’t actually think many people have any problem remembering what order the planets are in. It’s a bit like “Richard Of York Gave Battle In Vain” or “Roy G. Biv”. It isn’t really hard to remember what order the colours of the rainbow are because they blend into each other: orange is reddish yellow, indigo bluish violet and so on. Indigo in fact is just a kludge so they add up to seven. It’s not that it isn’t a real spectral colour so much as that lime green and cyan are too, but don’t get a mention.

I have a dormant project on the Althist Wiki called ‘The Caroline Era‘, where I imagined that instead of history doing a seemingly weird swerve at the end of the 1970s CE, it just carried on going in the same direction, with the post-war consensus being preserved. It turns out to be messy and difficult to contrive circumstances in which this could’ve happened. No fewer than seven major trends would have to have been different beforehand in order for this to have continued, one of which occurred as early as 1820. This alternate history also has different astronomy, not because there’s any difference in the planets, moons and the like but because the attitudes towards them were preserved and the technology available for investigating them advanced more slowly, in a way. Two of the ways in which this manifests itself are in the names of the solar planets and what’s considered a planet.

Back in the day, a planet was considered a large round non-luminous object orbiting the Sun independently, more or less. There wasn’t a firm definition but this is probably what people would agree with if you described them that way. I have already gone over the rather dubious procedures which led to this being changed to something most ordinary people would disagree with. Before this happened, however, astronomers, science fiction writers and others practically had a name picked out ready to apply to the next major planet to be discovered: Persephone. Persephone is kind of supposed to be the name of the planet, except that there’s a long-established asteroid called Persephone too. That said, there are also many duplicate names in the system and it doesn’t seem to have stopped astronomers reusing them. Ganymede springs to mind. Also, there’s a Latin version, Proserpina, which is also an asteroid, discovered quite early. Nonetheless the opinion is expressed that any “proper” planet out there beyond Pluto will not be called Persephone for this reason.

When Eris was discovered, it wasn’t given a name because its discovery was the main cause of controversy over the definition of a planet, which I’ve already said I consider rather silly. Because it wasn’t clear how it should be regarded, and there are different naming conventions for differently-classified objects in the system, it couldn’t be officially named. It was, though, given the unofficial name Xena after a show I’ve never seen called ‘Xena, Warrior Princess’, and its moon was given the name Dysnomia. The problem Eris was seen to pose was that if it were to be admitted into official planetaricity, the chances are that a lot of other similar worlds would also have to be called planets, and we could well have ended up with more than a hundred official planets. Now I have to admit that one of the things which annoyed me about what I now think of as the children’s space horror book ‘Galactic Aliens‘ (my review is on that page) was its portrayal of star systems as containing dozens of planets, which seemed unrealistic to me, but it now appears that it’s merely a question of definition, and the slight sense of disease I feel at this is not widely shared. The IAU decided to redefine “planet” because of Eris, making its name, after the goddess of discord, highly appropriate because that proved to be unpopular with the public. I presume the motive for calling it that was its disruption of the concept of “planet”, and it certainly succeeded in sowing discord when it provoked the turn against Pluto’s planethood among IAU members.

Eris is comparable in size and mass to Pluto and the probable former plutino Triton. Eris is a mere two percent smaller than Pluto in diameter and 27% more massive, which kind of makes the two cross over and means there isn’t much to choose between them. Hence there is a sense of fairness in excluding Pluto as a planet if Eris isn’t alowed to be one either. Nonetheless, if it had been discovered under different circumstances it would almost certainly have been thought of as one. There is no reason why, if you look at Pluto as a planet, as we did for many decades, you shouldn’t also look at Eris as one.

Compare and contrast this with Sedna. Not to diss the world, but it’s only a little larger than Ceres. Its mass is unknown because it seems to have no moon, which is unusual for these objects. It counts as a dwarf planet, to be sure, but Pluto and Eris are on a different scale.

Naturally Eris has never been visited. It’s the seventeenth largest world in the system, and the largest never to have had a spacecraft sent to it or past it. It averages almost 68 AU from the Sun, takes 559 years to orbit and is currently about a hundred AU from us. Sunlight takes thirteen hours to get there right now. At its closest approach, it comes slightly closer than Pluto’s average distance but it doesn’t cross Neptune’s orbit and is therefore not a plutino and doesn’t interact with Neptune. Its maximum distance from the Sun is 97.4 AU, which means it’s currently about as far away as it gets. I suspect that there are a number of Kuiper belt objects whose existence we only know of because they’re currently near perihelion, but this doesn’t apply to Eris. The Sun is currently over nine thousand times dimmer there than it is here. The distance of the world, and in fact I’m going to call a spade a spade and refer to it as a planet, the planet from the Sun is unprecedented in this series. It’s about five dozen times as bright as moonlight at that distance, meaning that finally the idea of a distant planet being so far from the Sun that it’s like night there may finally have begun to be fairly accurate, although a night of a brightness only seen on this planet had there been a fairly nearby supernova in the past few days. Surface temperatures vary between -243 and -217°C, so it doesn’t even get warm enough there to melt nitrogen or oxygen. It’s currently on the low side, and the seasons would be quite substantially determined by its distance from the Sun rather than just its axial tilt, although that’s also considerable at 78° if Dysnomia’s orbit is anything to go by.

Eris is bright. It isn’t like many of the other trans-Neptunian objects (TNOs), which are quite dark and also red. Its surface reflects most of the light back again, which makes it colder than other such worlds at comparable distances, and it’s also unlike Pluto, Charon and Triton in that respect. This is Charon:

. . .which looks quite like Pluto:

(to an extent), which in turn resembles Triton to a certain degree:

All three worlds have tholins on their surfaces to some extent and reflect up to 76% of sunlight. Eris could well be as bright as Enceladus. Something else is going on, or has gone on, there. One thing which very probably does happen is that it has a seasonal atmosphere. The surface is likely to be covered in a layer of frozen nitrogen and methane which will evaporate in a couple of centuries time when spring comes, at which point it will have a tenuous nitrogen-methane atmosphere for the summer, then with the onset of autumn this will freeze and snow onto the surface, once again covering it. This is a five and a half century process though, so we will never witness it. The last time Eris was where it is now was two decades before the Battle of Bosworth Field and three decades before Columbus reached the New World, and each season lasts something like the interval between the first Boer War and the present day, which means it’s just barely within the memory of my grandparents, and I’m middle-aged. That would be the average length. In reality, the winter is the longest season and the summer the shortest, and all seasons are somewhat affected by the considerable axial tilt. My ignorance of calculus makes it impossible to be more precise.

In considering Eris, we’re thrown back substantially onto pre-space age technology. Although there have been many advances in astronomical observation and reasoning since 1957, considering the planet is reminiscent of the kind of observation and reasoning astronomers used to have to use when all they had was what they saw through telescopes. This is not entirely true though, because conclusions were drawn on the basis of the actual space exploration of similar worlds, which didn’t just rely on light and other electromagnetic radiation, and the Hubble Space Telescope made a big difference too. There are also better modelling techniques. Even so, Eris is a dot in a telescope with another dot, Dysnomia, orbiting it, and astronomers have to base most of their studies on those. I’m once again reminded of Chesley Bonestell’s paintings of Saturn seen from different moons where the central subject more or less had to be the planet’s rather than the moons’ appearance because little was known about the characteristics of the moons themselves other than what was implied by their appearance through a less-than-ideal set of telescopes through Earth’s atmosphere, and their movements. Io, for example, was probably never depicted with a volcanic eruption taking place on it until the late ’70s or after. Nonetheless it’s still possible to go a long way with what we’ve got, and there’s even a kind of nostalgia to it. Just as we used to imagine oceans on Venus and canals on Mars, so we can project our wishes onto Eris. For instance, it could have the ruins of ancient alien space bases on it and we’d be none the wiser, although I very much doubt that’s so. Science fiction might be able to colour it in that way, but the genre hasn’t really developed in that direction. The planet is in a bit of a peculiar position because on the one hand it was fêted and imagined in detail for decades before it was discovered – mentioned on classic ‘Doctor Who’ for example – but when it was discovered for real, it ceased to be considered a planet within about a year and the kind of popular culture which existed by then had little space for such a concept as the “tenth” planet. It’s also been stated that not calling it the tenth planet is insulting to Clive Tombaugh’s memory, because he discovered Pluto. Calling it the ninth would be the same, and also wouldn’t make any sense. It’s either the tenth planet or not a planet at all.

The presence of Dysnomia is fairly typical for dwarf planets, which are often binary or at least have moons. Dysnomia is around seven hundred kilometres in diameter and is therefore almost certainly spheroidal. Here’s an image of the two together:

Eris is the brighter light in the middle, Dysomia the left lesser light. Since the moon can be observed to orbit Eris and perhaps also displace it as it does so, the time taken and the distance between the two can be used to calculate the mass of Eris, and the displacement would enable the density and mass of Dysnomia to be found. The moon might be a rubble pile, apparently, which surprises me because it seems too large not to have welded itself together. It was originally unofficially called Gabrielle due to the ‘Xena, Warrior Princess’ thing. Dysnomia orbits Eris once in almost sixteen days, averaging 37 000 kilometres separation in an almost circular path. It’s a lot less reflective, so it may not be made of the same stuff.

It’s possible to say a few of the usual things about Eris which follow from its known size, mass, density and orbit. It has a diameter of 2326 kilometres and a surface gravity 8.4% of Earth’s, which is about half Cynthia’s and close to Pluto’s. Its orbit is inclined 44° to the ecliptic. Its gleaming surface, which is almost uniformly bright, makes it difficult to measure its rotation, but it seems to be fourteen and a half days, making it just a little less than the “month” of Dysnomia. The planet is actually easily spottable through a large telescope. It wasn’t discovered before because its high orbital tilt keeps it away from the ecliptic where other planets generally stay. Even so, right now it is about ten thousand times too dim to be seen with the unaided naked eye, which is about as bright as a Sun-like star would look at the edge of our Galaxy, i.e. about twenty thousand light years away, so it ain’t exactly bright from this distance. It spends about thirty years in each of the maybe four zodiacal constellations it passes through and is currently in Cetus, the Whale.

Eris is not a plutino but a scattered disc object. The scattered disc is not the Kuiper belt, which consists of objects orbiting close to the plane of the Solar System, but comprises objects with highly tilted orbits such as Eris itself and many others, whereas the Kuiper belt planetoids orbit close to the plane of the inner system. The planet, however, still is quite remarkable as it shines forth compared to many of the others in the scattered disc, which have probably yet to be discovered due to their low albedo. It’s a little hard to imagine what could be so exceptional of Eris, it being, like the others, remote from other such objects barring its moon, and other scattered disc objects also have moons, often large compared to their own bulk like Dysnomia. However, discussion of this should wait for another time when I’ll be going into trans-Neptunian objects in more depth.

The surface area is almost seventeen million square kilometres, which is larger than any continent except Eurasia. It has a 26-hour day. It’s higher in rock than many other outer worlds. There’s very little else to say about Eris because so little is known about it, but it’s certainly a fair target for exploration as it’s certainly unusual. The problem is that because the charisma of being declared a planet was denied it, it’s harder to make a case for visiting it. Pluto didn’t suffer this problem because New Horizons was launched a few months before it lost its status. With current spaceflight technology, it would take a spacecraft nearly a quarter of a century to reach it, and once there it would take a radio signal more than half a day to reach Earth at its current distance. It won’t reach its closest approach until the late twenty-third century. The only probe-based exploration undertaken was from New Horizons itself, which was actually further from Eris than Earth was at the time, the advantage being that it was seen from a different angle.

To be honest, it’s a tall order to try to say anything much at all about Eris, as you may have gathered, but there would surely be a lot to say if the opportunity arose to explore it. Right now this seems quite unlikely, and by the time it’s in a position to be visited, we’ll probably be extinct or have lost the ability to launch spacecraft, so don’t hold your breath.

Next time, I’ll be talking about Pluto’s moons, of which there are five known.

Neptune’s Smaller Moons

For Neptune, or rather knowledge thereof, the early 1970s CE were a simpler time. In fact any time between 1949 and 1989 was a simpler time. Back then, Kuiper having discovered Nereid, a smaller and peculiar moon, at the end of the ’40s, Neptune only seemed to have two moons: Triton and Nereid. This state of affairs continued until the end of the ’80s, which was approximately one Neptunian season. Four decades during which the planet only appeared to have two moons. I’ll start with that.

I’ve already mentioned Triton, the oddball moon of the Neptunian system two hundred times as massive as all its other moons put together, orbiting backwards and at an angle, in an almost perfectly circular trajectory. I haven’t mentioned the equally oddball second moon discovered, Nereid, and I say the early ’70s were a simpler time but in fact its own orbit is very peculiar. Nereid has the most eccentric known orbit of any moon. It sometimes feels like discussing the orbit of a celestial body is a bit tangential to the core of its nature, but orbits have important consequences for the nature of planets, moons and their neighbours, and in this case it’s so odd that it would be strange not to mention it, particularly back in 1971 when that was practically all that was known about it. It sometimes feels like the Solar System “frays at the edges” with all this stuff, because things out here are really quite outré compared to the relatively regular innards of this system we call solar. Nereid’s orbit is entirely outside Triton’s, approaching Neptune by 1 353 600 kilometres at its closest and moving out to a maximum of 9 623 700 kilometres distance from the planet. It takes five days less than a year to go all the way round, which is appealingly similar to Earth’s sidereal period. In fact of all Solar System objects its year seems closest to ours. No other moon is remotely as eccentric. At its closest, Neptune would be a little larger than the Sun is in our own sky, and at its furthest, six months later (so to speak), about the size of a lentil on one’s dinner plate. This is probably the result of Triton’s capture, which to me suggests there are other former moons wandering far beyond Pluto or even in interstellar space, or maybe in the “Gap“.

Nereid is small and grey. There is no good image. The best one is this:

Not very impressive, eh?

Unlike Triton, Nereid orbits in the usual direction, as do two other irregular moons Sao and Laomedea, further out. Another moon, Helimede, is a remarkably similar colour but orbits the other way. It’s considered to be a bit that chipped off of Nereid. Nereid itself is about 360 kilometres across on average and may be somewhat spherical but by no means perfectly so. It’s one of several bodies in the system which are right on the border of being round, and is almost as large as the definitely round (sans Herschel) Mimas, but also rather denser. Its shape is therefore hard to determine. Certainly its gravity would be sufficient to pull Mimas-like material into a spheroid, since it’s higher, but that very density may result in the moon being tougher and more able to support its own weight without collapsing. However, its variation in brightness probably means it’s quite irregular in shape and closer to Hyperion in form. Its colour is markèdly unlike that of most centaurs, and it’s therefore probably a “native” Neptunian moon. There’s water ice on its surface.

Proteus is the one which really surprised me. On the whole, the Voyager probes and others only discovered small moons, although Charles Kowal’s discovery of Leda skews that for the Jovian satellites because it’s unusually small for a telescopic discovery of that time. Proteus is actually the second largest Neptunian moon, being somewhat larger than Nereid, and is shown at the top of this post. It orbits the planet at 117 647 kilometres from the barycentre on average in a fairly round orbit, though nowhere near as round as Triton’s. It can be determined not to be perfectly spherical and is in fact not even particularly rounded, with dimensions of 424 x 390 x 396 kilometres. Its surface consists of a number of planes (or plains) with sharp angles between them at their edges and it’s uniform in colour, being somewhat reddish like many other outer system worlds. It was discovered by Voyager, but two months before the space probe got to Neptune.

Unlike Nereid, Proteus was close enough to Voyager 2 to be mapped. As can be seen above, it’s heavily cratered and its surface is therefore likely to be quite old, meaning that nothing much has happened to it in a long time. NASA also had a very steep “learning curve” with Proteus compared to Nereid as it went from being unknown to being mapped within a few weeks, whereas Nereid’s existence has been established for six dozen years now and still there is no map available except possibly the kind of vague albedo feature map which used to be done for Pluto before a spacecraft got there. It can also be seen through the Hubble Space Telescope. It’s fairly dark, probably because its surface consists of hydrocarbons and cyanides. The only named feature on its surface is the relatively large crater Pharos, 260 kilometres across, but due to its somewhat irregular shape this fails to give it the “Death Star” appearance Mimas has. Proteus is also receding from Neptune due to tidal forces and is now eight thousand kilometres further from it than when it first formed. Unsurprisingly, given that it was undiscovered for so long, it’s a lot darker than Nereid.

The inner moons generally are coated in the same material as Proteus. A couple of them are quite notable. For instance, Larissa, which is 194 kilometres in diameter, was accidentally observed passing in front of a star in 1981, leading to the correct but unwarranted conclusion that Neptune has rings. The chances of a moon of that size being seen to cover a star are very small just anyway, but in Neptune’s case it’s even less likely because it moves against the “fixed” stars so slowly, taking almost three months to cover a distance equivalent to the face of the Sun. Larissa’s period is about twelve hours and it orbits only 73 400 kilometres above the centre of Neptune, putting it close to the Roche Limit, where large bodies are torn apart by gravity. It was, however, given a provisional designation in ’81, namely S/1981 N1, so it was accepted as a moon back then. Like the other inner satellites, it’s likely to be a rubble pile, without enough gravity to pull itself together as a solid object. It may be a future ring.

Another somewhat interesting moon is Hippocamp, which is so dim Voyager failed to notice it and had to wait for the Hubble Space Telescope to discover it, which was done by the combination of a number of images as even then it was too faint to be spotted. It seems to reflect less than ten percent of the light falling on it. It’s only seventeen kilometres across.

The closest moon to Neptune, and in fact to any solar gas giant at all, is Naiad, taking only seven hours to travel round the planet. It’s quite elongated at eight by five dozen kilometres, and will either become a ring or fall into the atmosphere in the relatively near future. Thalassa, the next moon out, is coörbital with it. Their orbits are only eighteen hundred kilometres apart but they never approach that closely because they move north and south of each other as they orbit, putting them a minimum of 2 800 kilometres apart. It’s about the planet’s radius from the cloud tops, making Neptune occupy most of its sky. This would make the surface look deep purple if it has a reddish coating like the others.

Like some other moons, the naming scheme has the prograde moons end in A, the retrograde in E and the highly tilted in O. The two outermost moons, Psamathe and Neso, are relatively close to each other, and stand in contrast to Naiad by being the most distant moons of any known planet at forty-six and fifty million kilometres. Neptune’s lower mass also gives them exceedingly long years of around a quarter of a century.

That’s it for Neptune and its moons, and I’ve already done Pluto, so next stop Eris.