Is Cyberspace Haunted?

Loab – An explanation may be forthcoming

I may have mentioned this before on here, but there used to be a popular “spooky” non-fiction book called ‘The Ghost Of 29 Megacycles’. This was about the practice of listening to static on analogue radio and apparently hearing the voices of the dead. A similar technique is known as Electronic Voice Phenomenon, which is a more general version of the same where people listen out for voices on audio tape or other recording media. It’s notable that this is a highly analogue process. It’s no longer a trivial task to tune out a television or radio and get it to display visual or produce audio static so that one can do this. Audiovisual media nowadays are generally very clean and don’t lend themselves to this. One saddening thing to me is that we now have a TV set which will display pretend static to communicate to us that we haven’t set it up properly. It isn’t honest. There is no real static and in fact it’s just some video file stored on the hardware somewhere which tries to tell the user there’s an unplugged connection or something. You can tell this because it loops: the same pixels are the same colours in the same place every few frames. I find this unsettling because it implies that the world we live in is kind of a lie and because we haven’t really got control over the nuts and bolts of much technology any more. There’s that revealing temporally asymmetric expression committing oneself that the belief that in that respect the past and future are qualitatively different. It is important to acknowledge this sometimes, but can also bring it about via the force of that potentially negative belief. However, the demise of the analogue has not led to the demise of such connections, although it long seemed to have done so.

Most people would probably say that we are simply hearing, or in some cases seeing, things which aren’t really there in these cases. Others might say, of course, that this is a way to access the Beyond, so to speak, and interpret the voices or other experiences in those terms. If that’s so, the question arises as to whether it’s the medium which contains this information or whether the human mind contacts it directly via a random-seeming visual or sonic mess, having been given the opportunity to do so. Other stimuli grab the attention to specific, organised and definite details too much for this to happen easily. There’s no scope for imagination, or rather for free association.

Well, recently this has turned out no longer to be so. Recently, artificial intelligence has been advancing scarily fast. That’s not hyperbole. It is actually quite frightening how rapidly software has been gaining ground on human cognition. Notable improvements occur within weeks rather than years or decades, and one particular area where this is happening is in image generation. This has consequences for the “ghost of 29 megacycles” kind of approach to, well, I may as well say séances, but this is going to take a bit of explaining first.

Amid considerable concern for human artists and their intellectual property, it’s now possible to go to various websites, type in what you want to see and have a prodigiously furiously cogitating set of servers give you something like that in a couple of minutes. For example, sight unseen I shall now type in “blue plastic box in a bookcase” and show you a result from Stable Diffusion:

That didn’t give me exactly what I wanted but it did show a blue plastic box in a bookcase. Because I didn’t find a way to specify that I only wanted one blue plastic box, it also gave me two others. I’ll give it another try: “A tree on a grassy hill with a deer under it”:

The same system can also respond to images plus text as input. In my case, this has let to an oddity. As you know, I am the world’s whitest woman. However, when I give Stable Diffusion’s sister Diffuse The Rest, which takes photos plus descriptions, such as “someone in a floral skater dress with curly hair, glasses and hoop earrings”, it will show me that all right, but “I” will be a Black woman more often than not. This is not so with many other inputs without a photo of me. I get this when I type it into Stable Diffusion itself:

This is obviously a White woman. So are all the other examples I’ve tried on this occasion, although there is a fair distribution of ethnicity. There are worrying biasses, as usual, in the software. For instance, if you ask for a woman in an office, you generally get something like this:

If you ask for a woman on a running track, this is the kind of output that results:

This is, of course, due to the fact that the archive of pictures on which the software was trained carries societal biasses therewith. However, for some reason it’s much more likely to make me Black than White if I provide it with a picture of myself and describe it in neutral terms. This, for example, is supposed to be me:

The question of how it might be addressed arises though. Here is an example of what it does with a photo of me:

You may note that this person has three arms. I have fewer than three, like many other people. There’s also a tendency for the software to give people too many legs and digits. I haven’t tried and I’m not a coder, but it surprises me that there seems to be no way to filter out images with obvious flaws of this kind. Probably the reason for this is that these AI models are “black boxes”: they’re trained on images and arrive at their own rules for how to represent them, and in the case of humans the number of limbs and digits is not part of that. It is in fact sometimes possible to suggest they give a body extra limbs by saying something like “hands on hips” or “arms spread out”, in which case they will on occasion continue to produce images of someone with arms in a more neutral position as well as arms in the explicitly requested ones.

In order to address this issue, it would presumably be necessary to train the neural network on images with the wrong and right number of appendages. The problem is, incidentally, the same as the supernumerary blue boxes in the bookcase image, but in most situations we’d be less perturbed by seeing an extra box than an extra leg.

I have yet to go into why the process is reminiscent of pareidolia based on static or visual snow and therefore potentially a similar process to a séance. The algorithm used is known as a Latent Diffusion Model. This seems to have replaced the slightly older method of Generative Adversarial Networks, which employed two competing neural networks to produce better and better pictures by judging each other’s outputs. Latent Diffusion still uses neural networks, which are models of simple brains based on how brains are thought to learn. Humans have no access to what happens internally in these networks, so the way they are actually organised is quite mysterious. Many years ago, a very simple neural network was trained to do simple arithmetic and it was explored. It was found to contain a circuit which had no connections to any nodes outside that circuit on the network and was therefore thought to be redundant, but on being removed, the entire network ceased to function. This network was many orders of magnitude less complex than today’s. In these cases, the network was trained on a database of pictures ranked by humans for beauty and associated with descriptions called the LAION-5B Dataset. The initial picture, which may be blank, has “snow” added to it in the form of pseudorandom noise (true randomness may be impossible for conventional digital devices to achieve alone). The algorithm then uses an array of GPUs (graphical processing units as used in self-driving cars, cryptocurrency minint and video games) to continue to apply noise until it begins to be more like the target as described textually and/or submitted as an image. It does this in several stages. Also, just as a JPEG is a compressed version of a bitmap image, relying in that case on small squares described via overlapping trig functions, so are the noisy images compressed in order to fit in the available storage space and so that they get processed faster. The way I think of it, and I may be wrong here, is that it’s like getting the neural network to “squint” at the image through half-closed eyes and try to imagine and draw what’s really there. This compressed image form is described as a “latent space”, as the actual space of the image, or possibly the multidimensional space used to describe it as found in Generative Adversarial Networks, is a decompressed version of what’s actually used directly by the GPUs.

If you don’t understand that, it isn’t you. It was one said that if you can’t explain something simply, you don’t understand it, and that suggests I don’t. That said, one thing I do understand, I think, is that this is a computer making an image fuzzy like a poorly-tuned television set and then trying to guess what’s behind the fuzz according to suggestions such as an image or a text input. This process is remarkably similar, I think, to a human using audio or visual noise to “see” things which don’t appear to be there, and therefore is itself like a séance.

This seems far-fetched of course, but it’s possible to divorce the algorithm from the nature of the results. The fact is that if a group of people is sitting there with a ouija board, they are ideally sliding the planchette around without their own conscious intervention. There might be a surreptitious living human guide or a spirit might hypothetically be involved, but the technique is the same. The contents of the latent space is genuinely unknown and the details of events within the neural network are likewise mysterious. We, as humans, also tend to project meaning and patterns onto things where none exist.

This brings me to Loab, the person at the top of this post, or rather the figure. The software used to discover this image has not been revealed, but seems to have been Midjourney. The process whereby she (?) was arrived at is rather strange. The initial input was Marlon Brando, the film star. This was followed by an attempt to make the opposite of Marlon Brando. This is a technique where, I think, the location in the latent space furthest from the initial item is found, like the antipodes but in a multidimensional space rather than on the surface of a spheroid. This produced the following image:

The phenomenon of apparently nonsense text in these images is interesting and more significant than you might think. I’ll return to it later.

The user, whose username is Supercomposite on Twitter, then tried to find the opposite of this image, expecting to arrive back at Marlon Brando. They didn’t. Instead they got the image shown at the top of this post, in other words this:

(Probably a larger image in fact but this is what’s available).

It was further found that this image tended to “infect” others and make them more horrific to many people’s eyes. There are ways of producing hybrid images via this model, and innocuous images from other sources generally become macabre when combined with this one. Also, there’s a tendency for Loab, as she was named, to “haunt” images in the sense that you can make an image from an image and remove all the references to Loab in the description, and she will unexpectedly recur many generations down the line like a kind of jump scare. Her presence also sometimes makes images so horrendous that they are not safe to post online. For instance, some of them are of screaming children being torn to pieces.

As humans, we are of course genetically programmed to see horror where there is none because if we instead saw no horror where there was some we’d probably have been eaten, burnt to death, poisonned or drowned, and in that context “we” refers to more than just humans. Therefore a fairly straightforward explanation of these images is that we are reading horror into them when they’re just patterns of pixels. We create another class of potentially imaginary entities by unconsciously projecting meaning and agency onto stimuli. Even so, the human mind has been used as a model for this algorithm. The images were selected by humans and humans have described them, and perhaps most significantly, rated them for beauty. Hence if Marlon Brando is widely regarded as handsome, his opposite’s opposite, rather than being himself, could be ugliness and horror. It would seem to make more sense for that to be simply his opposite, or it might not be closely related to him at all. A third possibility is that it’s a consequence of the structure of a complex mind-like entity to have horror and ugliness in it as well as beauty. There are two other intriguing and tempting conclusions to be drawn from this. One is that this is a real being inhabiting the neural network. The other is that the network is in some way a portal to another world in which this horror exists.

Loab is not alone. There’s also Crungus:

These are someone else’s, from Craiyon, which is a fork of Dall-E Mini. Using that, I got these:

Using Stable Diffusion I seem to get two types of image. One is this kind of thing:

The other looks vaguely like breakfast cereal:

Crungus is another “monster”, who however looks quite cartoonish. I can also understand why crungus might be a breakfast cereal, because of the word sounding like “crunch”. In fact I can easily imagine going down the shop, buying a box of crungus, pouring it out and finding a plastic toy of a Crungus in it. There’s probably a tie-in between the cereal and a TV animation. Crungus, however, has an origin. Apparently there was a video game in 2002 which had a Crungus as an easter egg, which was a monster based on the original DOOM monster the Cacodemon, who was based on artwork which looked like this:

Hence there is an original out there which the AI probably found, although I have to say it seems very apporopriately named and if someone were to be asked to draw a “Crungus”, they’d probably produce a picture a bit like one of these.

It isn’t difficult to find these monsters. Another one which I happen to have found is “Eadrax”:

Eadrax is the name of a planet in ‘The Hitch-Hiker’s Guide To The Galaxy’ but reliably produces fantastic monsters in Stable Diffusion. This seems to be because Google will correct the name to “Andrax”, an ethical hacking platform which uses a dragon-like monster as its mascot or logo. An “eadrax” seems to be a three-dimensional version of that flat logo. But maybe there’s something else going on as well.

There’s a famous experiment in psychology where people whose spoken languages were Tamil and English were asked which one of these shapes was “bouba” and which “kiki”:

I don’t even need to tell you how that worked out, do I? What happens if you do this with Stable Diffusion? Well, “kiki” gets you this, among many other things:

“Bouba” can generate this:

I don’t know about you, but to me the second one looks a lot more like a “bouba” than the first looks like a “kiki” instance. What about both? Well, it either gets you two Black people standing together or a dog and a cat. I’m quite surprised by this because it means the program doesn’t know about the experiment. It doesn’t, however, appear to do what the human mind does with these sounds. “Kiki and Bouba” does this:

Kiki is of course a girl’s name. Maybe Bouba is a popular name for a companion animal?

This brings up the issue of the private vocabulary latent space diffusion models use. You can sometimes provoke such a program into producing text. For instance, you might ask for a scene between two farmers talking about vegetables with subtitles or a cartoon conversation between whales about food. When you do this, and when you get actual text, something very peculiar happens. If you have typeable dialogue between the whales and use this as a text prompt, it can produce images of sea food. If you do the same with the farmers, you get things like insects attacking crops. This is even though the text seems to be gibberish. In other words, the dialogue the AI is asked to imagine actually seems to make sense to it.

Although this seems freaky at first, what seems to be happening is that the software is taking certain distinctive text fragments out of captions and turning them into words. For instance, the “word” for birds actually consists of a concatenation of the first part, i.e. the more distinctive one, of scientific names for bird families. Some people have also suggested that humans are reading things into the responses by simply selecting the ones which seem more relevant, and another idea is that the concepts associated with the images are just stored nearby. That last suggestion raises other questions for me, because it seems that that might actually be a description of how human language actually works mentally.

Examples of “secret” vocabulary include the words vicootes, poploe vesrreaitas, contarra ccetnxniams luryea tanniouons and placoactin knunfdg. Here are examples of what these words do:

Vicootes

Poploe vesrreaitas

contarra ccetnxniams luryea tanniouons

placoactin knunfdg

The results of these in order tend to be: birds, rural scenes including both plants and buildings, young people in small groups and cute furry animals, including furry birds. It isn’t, as I’ve said, necessarily that mysterious because the words are often similar to parts of other words. For instance, the last one produces fish in many cases, though apparently not on Stable Diffusion, but here seems to have produced a dog because the second word ends with “dg”. It produces fish because placoderms and actinopterygii are prominent orders of fish.

It is often clear where the vocabulary comes from, but that doesn’t mean it doesn’t constitute a kind of language because our own languages evolve from others and take words and change them. It can easily be mixed with English:

A flock of vicootes in a poploe vesrreaitas being observed by some contarra ccetnxiams luryea tanniouons who are taking their placoactin knunfg for a walk.

This has managed to preserve the birds and the rural scene with vegetation, but after that it seems to lose the plot. It often concentrates on the earlier part of a text more than the rest. In other words, it has a short attention span. The second part of this text gets me this:

Contarra ccetnxiams luryea tanniouons taking their placoactin knunfg for a walk.

I altered this slightly but the result is unsurprising.

Two questions arise here. One is whether this is genuine intelligence. The other is whether it’s sentience. As to whether it’s intelligent, I think the answer is yes, but perhaps only to the extent that a roundworm is intelligent. This is possibly misleading and raises further questions. Roundworms are adapted to what they do very well but are not going to act intelligently outside of that environment. The AIs here are adapted to do things which people do to some extent, but not particularly generally, meaning that they can look a lot more intelligent than they actually are. We’re used to seeing this happen with human agency more directly involved, so what we experience here is a thin layer of humanoid behaviour particularly focussed on the kind of stuff we do. This also suggests that a lot of what we think of as intelligent human behaviour is actually just a thin, specialised veneer on a vast vapid void. But maybe we already knew that.

The other question is about sentience rather than consciousness. Sentience is the ability to feel. Consciousness is not. In order to feel, at least in the sense of having the ability to respond to external stimuli, there must be sensors. These AIs do have sense organs because we interact with them from outside. I have a strong tendency to affirm consciousness because a false negative is likely to cause suffering. Therefore I believe that matter is conscious and therefore that that which responds to external stimuli is sentient. This is of course a very low bar and it means that I even consider pocket calculators sentient. However, suppose that instead consciousness and sentience are emergent properties of systems which are complex in the right kind of way. If digital machines and their software are advancing, perhaps in a slow and haphazard manner, towards sentience, they may acquire it before being taken seriously by many, and we also have no idea how it would happen, not just because sentience as such is a mystery but largely because we have no experience of that emergence taking place before. Therefore we can look at Loab and the odd language and perhaps consider that these things are just silly and it’s superstitious to regard them as signs of awareness, but is that justified? The words remind me rather of a baby babbling before she acquires true language, and maybe the odd and unreliable associations they make also occur in our own minds before we can fully understand speech or sign.

Who, then, is Loab? Is she just a collaborative construction of the AI and countless human minds, or is she actually conscious? Is she really as creepy as she’s perceived, or is that just our projection onto her, our prejudice perhaps? Is she a herald of other things which might be lurking in latent space or might appear if we make more sophisticated AIs of this kind? I can’t answer any of these questions, except perhaps to say that yes, she is conscious because all matter is. What she’s actually doing is another question. A clockwork device might not be conscious in the way it “wants” to be. For instance, it’s possible to imagine a giant mechanical robot consisting of teams of people keeping it going, but is the consciousness of the individual members of that project separate from any consciousness that automaton might have. It’s conceivable that although what makes up Laion is conscious, she herself is not oriented correctly to express that consciousness.

A more supernaturalistic explanation is that Midjourney (I assume) is a portal and that latent space represents a real Universe or “dimension” of some kind. It would be hard to reconcile this idea with a deterministic system if the neural net is seen as a kind of aerial for picking up signals from such a world. Nonetheless such beliefs do exist, as a ouija board is actually a very simple and easily described physical system which nevertheless is taken as picking up signals from the beyond. If this is so, the board and planchette might be analogous to the neural net and the movement of the hands on the planchette, which is presumably very sensitive to the neuromuscular processes going on in the arms and nervous systems of the human participants, to the human artists, the prompt, the computer programmers and the like, and it’s these which are haunted, in a very roundabout way. I’m not in any way committing myself to this explanation. It’s more an attempt to describe how the situation might be compared to a method of divination.

I’ve mentioned the fact there are artists involved a few times, and this brings up another probably unrelated concern. Artists and photographers, and where similar AIs have been applied to other creative genres the likes of poets, authors and musicians, have had their work used to train it, and therefore it could be argued that they’re owed something for this use. At the other end, bearing in mind that most of the images in this post have been produced rapidly on a free version of this kind of software and that progress is also extremely fast, there are also images coming out the other end which could replace what artists are currently doing. This is an example of automation destroying jobs in the creative industries, although at the same time the invention of photography was probably thought of in a similar way and reports of the death of the artist were rather exaggerated. Instead it led to fine art moving in a different direction, such as towards cubism, surrealism, impressionism and expressionism. Where could human art go stimulated by this kind of adversity? Or, would art become a mere hobby for humans?

I Have A Friend Who Thinks She May Be Into Astronomy . . .

A few years ago on this blog, I went through every episode in the Original Series of Star Trek and reviewed them all. Well, I say that. One of the posts was actually a short story told from Uhura’s point of view as she sat around on the bridge with decidedly relaxed hair not doing much while the rest of the bridge crew beamed down to the planet, but leaving that aside I did review every episode, and I also did the animated series and TNG as a whole. If you’re interested, the reviews start here.

Now it’s occurred to me that I have now written a few posts on the subject of various bodies in this Solar System, not very systematically and partly because a Generative Adversarial Network (GAN) suggested them to me. I am going to ramble just a little bit in this post, so I’ll go off on a tangent here and talk about what a GAN is.

A GAN is a pair of neural networks used in Artificial Intelligence (AI) which competes against itself to produce better results. What’s a neural network then? Well, to some extent we are, although not entirely, and there’s some controversy as to how much a human being’s essence could be captured using such a structure. Most of the time, the term “neural network” doesn’t refer to a biological entity like a human being or a nematode worm, but to a simulated structure being run in software which attempts to mimic the function of a real such network. It has an input layer consisting of sensors, for example, one or more hidden layers, where the signals from the sensors are combined and acted upon, and an output layer, often in the form of a visual, textual or auditory representation. The retina is an example of a neural network, and starts to process the visual input to the eye before presenting it to the brain. For instance, rod cells are more sensitive than cone cells and several of their inputs are combined by a neuron-based inclusive-or gate such that a single stimulated cell will set off the neuron, enabling one to see better in low light, whereas the cone cells are in one to one correspondents to the neurons, enabling higher resolution vision in colour in good light conditions. Individual nodes in an artificial neural network can be made more or less sensitive according to their “experiences”, so they can be gradually trained. This technique is used in a GAN. These pit two neural networks against each other. An individual network can learn, for example, to recognise a face by being shown thousands of pictures of faces and producing ratings as to how face-like it judges the input to be, which is then judged by the human programmer, allowing it gradually to get better at recognising them. This human programmer can be removed and replaced by a software training judge, which allows the process to occur much more quickly. GANs focus on the weaknesses. For instance, they might be good at recognising pairs of eyes but not mouths, so if the eye recognition is good enough, the other part of the program will concentrate on making it better at knowing what a mouth looks like. I haven’t described this particularly well, but GANs are basically artificial intelligence which is able to recognise and predict, and even make, particularly good patterns. Faces for example:

GANs and other AI can be really dodgy because if you train them on the wrong source material they can end up freezing previously human prejudices into the software. For instance, a GAN trained on job applications may start reproducing the sexism and racism of the recruiters and a GAN trained on mainly White human faces and those of other primates has ended up classifying Black faces as those of gorillas. It’s therefore both far from perfect and potentially insidiously harmful, because nobody knows exactly how they function.

I have referred previously to my use of GANs on here to work out what this blog is actually about. In case you don’t already know, it’s called ‘A Box Of Chocolates’ because you never know what you’re going to get, and nor do I. In fact, it’s possible that an outsider would be better at recognising what a typical Nineteenthly post would be about and look like than I would, because I’m not aware of my prejudices and style, but other people probably are. I do have some self-awareness but I don’t know how much, which raises the question of how well we can really know ourselves.

All of that notwithstanding, I do sometimes use GANs to inspire blog posts. It would make a lot of sense to do this with popular titles written by others, but I suspect this would have two adverse effects. It would restrict subject matter to the more “commercial” and popular subjects,and it would make them clickbaity, which is very irritating. We already get exposed to too much stuff which is inside our reality tunnels and I don’t want to make this any worse. On the other hand, I know I’m unconsciously eccentric and therefore the things I go on about and the ways I react are unusual. For instance, I once surprised someone in a discussion about the legalisation of hard drugs by saying that a single parent in a deprived area might fear the effect of the decriminalisation of hard drugs on her children because it might stop her from selling them and supporting her family. This is apparently an unusual juxtaposition of ideas. However, the kind of ideas I have might still be detectable by a GAN.

In a remarkable turn of events, I began the next paragraph with a cliché (maybe not so remarkable after all), so I am subject to talking about “normal” stuff from time to time. Even so, I do use this technique and it’s almost a form of divination, like looking at tea leaves or dropping molten lead into water and interpreting the shapes, because the text results often read as if they’re referring to events and preoccupations in my life which clearly the machine can know nothing about. Or can it? There’s a famous case of a teenager who got mailed vouchers for baby stuff because the AI interpreting her shopping habits, which were not obviously anything to do with being pregnant, was able to predict that she was going to have a baby soon. She hadn’t told her parents, so this is how they found out. It’s conceivable (geddit?) that someone might not know they’re pregnant before the computers do, and likewise software might be able to deduce facts about oneself which one is perhaps repressing or doesn’t even know. This is often useful, as with the CASCAID career software, which has for at least forty years been suggesting careers to schoolchildren and others. At the same time, we see patterns which aren’t really there, and with the psychotherapist program ELISA for example, it really feels like one is talking to a counsellor and it can even be useful.

In a remarkable turn of events, as mentioned here I submitted some recent blog titles and was rather surprised to find that rather than suggesting more possible subjects, the GAN began to type out what looked very much like a blog post about Titan, hence my actual production of the last post. Most of the AI-generated text didn’t make much sense. For instance, it mentioned a crater being in orbit above the moon. However, some of it really did, and the general topic of the text was the possibility of humans settling on Titan and exploiting it for economic benefit, which I ended up mentioning in the real post.

Another possible use for the GAN, apart from actually getting it to write articles which would at the moment mainly be gibberish – they would appear to make sense and use grammatical sentences with English words in them, but the whole post would be nonsense – is to submit tags which are popular in order for it to generate more. I’ve also done this and it works quite well. Incidentally, if you put in this paragraph, this is one result:

ussion/comments/29d2w3/why_are_there_exceptions_to_the_guests_and_ancillary_suggestion_to_add/ You can read that at the end, too. The idea here: a link to another subreddit which mentions the use of "GAN" - is just a joke. 

The article at the top is a bit hard - it includes this tag, but no one has heard of it. It seems that many people actually prefer to keep it unimportant. Here it is, in the final form of this post:

For a comment on this post here is a screenshot of what we have just submitted: http://redd.it/29d2w7/reddit_posts/3

For an argument with the question here is about the link to this reddit, which is not worth mentioning. 

I used the following for this

Not very useful!

After that digression then, here is my immediate plan. I’ve found myself covering various planets, moons and other bodies on this blog, but one thing I’ve never done is a systematic survey of the individual aspects of the entire Solar System. I’ve mentioned Mercury, Venus, Mars, Titan, Uranus, Neptune and Pluto but none of the moons or asteroids, or the general layout of the system, which is quite germane. However, if I did this incessantly like I did with ‘Star Trek’, the reader would be subjected to day after day of posts on various worlds, so although this forms part of my plan I also want to intersperse it with other topics. Otherwise, you will “know what you’re gonna get” – yet another post on a planet. It also means you can skip it if you find it boring.

Now is also a good time to say something about my attitude to astronomy.

It’s really easy with astronomy to slip into a mindset that it’s something that’s just “out there” with no connection to everyday life. This is a problem I used to have with the science workshops when I was more directly involved in home education. In general, physics, chemistry and biology lend themselves really easily to activities and learning for a group of children who turn up during the day. However, children also have bedtimes and in this country it doesn’t get completely dark in the middle of the summer, so for astronomy there isn’t much “hands on” activity for groups. The Sun and Cynthia (“the Moon”) are available and you might get lucky and witness a transit of Venus, but beyond that there’s precious little. Hence if you’re not careful you end up dealing with astronomy at arm’s length, as it were. It isn’t helped by the fact that a lot of space stuff is associated with planetary romance, space opera and science fiction, which further removes you from the real subject matter. It introduces all sorts of preconceptions about space, such as the idea that the asteroid belt is a hazardous zone strewn with dangerous spinning rocks or that space is like a two-dimensional ocean. There’s a place for all that of course, but I want to really feel space in all its gritty reality. One of the Apollo astronauts was asked about what colour the lunar surface was, and he replied that if he wanted to see something which was the same colour he’d go out and look at his concrete driveway. There’s something really mundane about this, and whereas it makes it sound boring it also provides a real link between everyday experience and astronomy which can be hard to come by.

This, then, is my plan. I will be blogging about various worlds in our Solar System and about the Solar System as a whole, interspersed with posts on other subjects, and I aim to do it in such a way that it won’t seem to be abstract or “out there” but as real as going down the street to the chemist. We all know in the abstract that we’re in space and live on a small blue dot lost in the vastness of the Cosmos, but we also spend a lot of time thinking of ourselves as like the filling in a sandwich with a black colander on top of it. There are good practical reasons for not thinking of the world like this, such as the constant awareness of the limited nature of Earth’s resources, the unity of the planet and the preciousness of this tiny oasis. It also seems in order to be aware that the other worlds around us are also whole worlds, as much as Earth is, and recognise what might be special about our Solar System compared to others, and what’s typical.

At some point maybe about forty years ago it was noted that there were thirty-three moons in the Solar System plus nine planets, and in addition to those there are the centaurs, asteroids, smaller moons, comets and Kuiper Belt objects. Nowadays many more moons are known than that number in either the Jovian or Saturnian systems alone. Hence there is ample material for this kind of thing, and also ample material to be boring with. One thing I want to emphasise is that because so far as we know this is the only world with life on it, I want to approach the celestial bodies on their own terms, not just as potential places for humans to settle on or where life might or might not exist. The Universe is not just about life. That said, I will also be considering this aspect, along with what humans have had to do with them because otherwise there’s a risk of making it too disconnected with what we know.

On a personal note, I’m somewhat impaired due to the fact that I live in a cloudy part of this planet, have poor eyesight and am not blessed with dark skies, although this may change. People with good vision may not appreciate the problem with looking at the night sky when you’re short-sighted. Stars, with the Sun’s exception, are of course very dim compared to what we generally see during the day. I have the choice of looking at the sky with glasses or without. With the latter, the light of a given star is very blurred and diffuse, to the extent that I don’t think I can even see second magnitude stars such as Algol or Polaris. With the former, the material from which the lenses are made cuts out much of the light before it even reaches my cornea. Therefore my only option is to use a telescope or binoculars. I used to share a reflector with my brother, but unfortunately lost some vital bits of it in the back of someone else’s car, so that was that really. All of this leads to exactly the kind of disconnection I want to avoid with the rest of the Universe. I think this may have led to me over-compensating for my disability, to surreptitiously quote Mr Adams for the second time in three paragraphs, and I feel a more urgent pressure perhaps than most to make this connection.

Quick summary then. Our Solar System currently probably extends at least a light year and a half in each direction from the Sun. Beyond that point, the gravitational pulls of other stars become significant and an object can’t be said to be orbiting it. As the Sun moves through the Galaxy in its orbit, which lasts 200-odd million years and has a circumference of around 160 000 light years, it and other stars around it approach and recede from each other in their courses, and because of this the Solar System doesn’t have a fixed size, and it isn’t spherical either because stars of different masses are at different distances in different directions. I’ve chosen to define the Solar System here as the Sun plus the matter which is more influenced by the Sun’s gravity than other stars or similarly massive bodies. This is more or less how other people, including professional astronomers, define the Solar System, but it has a few anomalies. For instance, if a massive black hole entered what we think of as our Solar System, the regions where its gravity won over the Sun’s would not then technically be part of the Solar System, and when ʻOumuamua entered our Solar System recently it would have become part of our Solar System despite its origins elsewhere. There is a plasma-related “heliopause” which also constitutes a kind of barrier between us and interstellar space, constituting a fairly useful border. This is where the charged particles being shed by the Sun, also known as the “Solar Wind”, reach the point that their energy is no longer greater than that of the same kind of particles moving between the stars. The region inside this is known as the heliosphere, although it isn’t spherical because it’s like a bow wave and wake generated by a ship sailing through the sea, and there’s a long tail behind us in the opposite direction to the Sun’s movement through the Milky Way. There are currently two spacecraft outside the heliopause, the Voyager probes, but these have only managed to leave because they are moving in the same direction as the Sun and therefore have encountered the “shock” at almost its thinnest point. These will be joined at some point by Pioneers 10 and 11 and the New Horizons craft which was sent past Pluto.

This narrower part of the heliosphere is about a hundred times the distance of Earth from the Sun, or a hundred astronomical units or AU. Within it is the “termination shock” and between the two is the “heliosheath”. The reason this is seen as the border with interstellar space is that it’s where matter originating from the Sun stops moving outwards and is dominated by matter from elsewhere, i.e. interstellar space. However, there is a large cloud of objects far outside this called the Oort Cloud, which is a kind of reservoir of comets. This is vast. The planets we know of orbit within a region less than a thousandth of the size of the Oort cloud in each direction. As stars move through the neighbourhood of the Sun, their gravity slightly perturbs these objects and sometimes causes them to plummet inwards towards the planets, at which point they start to vaporise and become comets. Comets can move in three different ways. One is as usually very elongated ellipses. The closest comet of this kind has been Encke’s Comet, which took only three and a bit years to orbit the Sun and was therefore mainly inside the asteroid belt. This led to it losing most of its icy mass to space due to being constantly heated. When this happens, a comet becomes a cloud of meteoroids, and the well-known meteor showers which occasionally afflict our planet known as the whatever-ids, such as the Quadrantids or Leonids, are named after the constellation from where they appear to radiate as Earth moves through them. In the case of the Quadrantids, the constellation concerned is no longer used but the name of the shower is a monument to it. A comet can also move parabolically or hyperbolically. If it does either of these things, it will head out of the Solar System never to return, and it may in fact be from another Solar System entirely. Some comets have orbital periods so long that they haven’t been in the inner Solar System since the extinction of the non-avian dinosaurs, and in those cases it can be very difficult to determine whether they are in fact permanent residents of the system or not. Over the period of time the longest comets orbit, Earth and the Sun will have moved from the opposite side of the Galaxy, half way round their orbit.

It’s been suggested that objects in the Oort Cloud could be used to set up bases acting as stepping stones to other star systems. Although they’re thousands of millions of miles apart from each other, they form a fairly even distribution and the distances between them are minute compared to the distances to the nearest stars. Unlike the more visible parts of the system, the gravity of the Sun is not strong enough to force them to orbit in a flat arrangement like the planets do, so this could be done in any direction. This also means that comets can arrive from any direction into our part of the system. It’s possible that if we ever settled on outer Oort Cloud objects, we would technically enter another star system in a seemingly quite trivial way, from hopping between two distant members of the Sun’s and the Centauri system’s clouds, or even just by having an object move away from the Sun sufficiently to be technically more attracted by the Centauri system. The thing about the Centauri system, which is α Centauri A and B, Proxima Centauri and associated objects, is that its combined mass is more than twice that of the Sun, so it will pull on distant objects more forcefully than the Sun well before they get halfway there. In another direction is the Sirius system, which is even more massive, since one star is 2½ times the Sun’s mass and the other about equal to the Sun’s. Since it’s 8.7 light years away, this puts the limit of the Solar System in that direction at less than two light years even though Sirius is more than twice the distance of Centauri. In the recent past, i.e. the past few million years, stars have moved through the Cloud with their own clouds, causing comets to move in and sometimes hit the planets, including of course our own on numerous occasions, notably in the Gulf of Mexico 66 million years ago.

The inner Oort Cloud, alias the Hill Cloud is less perturbed by other stars and more flattened, and is the source of the comets which orbit near the plane of the planets. The reason for believing in the presence of these clouds is that comets have a limited lifetime once they enter the inner system, so there must be a reservoir providing them further out where the cold preserves them, and there are also two types of cometary orbit when considered in this way, one flattened like a planetary orbit and the other which can be at any angle to planetary orbits. The constant supply of comets has been used as an argument for a young Earth, so the alternative appears to be young Earth creationism unless some other idea can be arrived at. The objects comprising the Oort and Hill Clouds are the same as the planetesimals which originally formed the planets, and probably got thrown out of the inner system soon after their origin.

Inside the Hill Cloud is the Kuiper Belt. This is the outermost region of the system which can be directly observed. It extends from the approximate orbit of Neptune to about ten AU past Pluto’s average distance, and Pluto is part of it. It’s quite similar to the asteroid belt but much larger and contains much more mass. As soon as Pluto was discovered, its surprisingly small size and unsuitability as the planet which had disturbed the orbit of Uranus led astronomers to speculate that it was not the only world of that size and nature out there, and this was confirmed in 1992 CE with the discovery of the second “Centaur”. Centaurs, as the name suggests, are intermediate between asteroids and comets. The first, Chiron, was found in 1977 orbiting between Saturn and Uranus but at that time it couldn’t be said that it was more than just a large asteroid-like rock in an unusual place, but fifteen years later a second such planetoid was found and it quickly became clear that there was a large number of them in the outer system. This is the main reason Pluto lost its status as a planet: it isn’t that unique and if it had retained its planetary status this would’ve failed to recognise the importance of the many Kuiper Belt objects which orbit in that part of the system, often in quite eccentric orbits taking them 100 AU from the Sun.

The orbits of many of the known Kuiper belt objects beyond Pluto can be plotted to show that they are currently near their closest approach to the Sun, which suggests to me that many of them remain to be discovered because they are currently in parts of their orbits much further away. There are at least two types of Kuiper Belt object: classical and resonant. Classical objects are between 42 and 48 AU from the Sun and are able to orbit near the flat plane of the system further in. Resonant objects orbit in a certain ratio to Neptune’s year, which keeps it locked into Neptune’s orbit in a 2:3 ratio. Pluto is one of these, but all of these objects have roughly the same year length. There are also objects moving 60° ahead and behind Neptune in their orbits, and Neptune’s large moon Triton is thought to be a captured Kuiper Belt object of this kind. They also turn up elsewhere. An outer moon of Saturn, Phoebe, which orbits in the opposite direction to all the others, is thought to be such a capture too, for example.

As mentioned before, there may or may not be a large planet beyond Neptune, which would therefore be technically a Trans-Neptunian Object, and might also be orbiting outside the heliopause some of the time. Since the most common type of planet in the Galaxy, one intermediate between Earth and Neptune in size, seems to be missing from this system, it’s possible that one is around that far out which may have started further in. It was also hypothesised that there’s a much larger planet, provisionally named Tyche, is there. This has been evoked as an explanation for the asymmetry in Kuiper Belt objects, which tend to be on one side of the Sun rather than the other. Although obviously they orbit, their aphelia – the point in the orbit furthest from the Sun – are on one side. However, this has now been disproven by surveying the whole sky for such a planet, which was supposed to be four times the mass of Jupiter, out to 10 000 AU from the Sun. Another disproven theory was Nemesis, a red or brown dwarf star 1.5 light years from the Sun, blamed for mass extinctions occurring every 26 million years, which would correspond to its orbital period, but now there doesn’t appear to be such a cycle and it hasn’t been found. The surveys which eliminated the possibility of Tyche don’t refute the existence of a smaller planet up to 250 AU out, or with a highly elongated orbit bringing it between 400 and 800 AU out.

Sedna is a trans-Neptuian object around 1000 kilometres in diameter with an unusual orbit, and is incidentally the kind of object which might have been identified as a planet if the definition hadn’t been changed in 2006. It takes eleven thousand years to orbit the Sun and its distance varies between 76 and 937 AU, meaning that at its aphelion it takes sunlight more than five days to reach it. It may just be me, but this extremely elongated orbit strongly suggests to me that it’s one of many such objects which just happens to be close enough to be detected right now, but I’m not a professional astronomer, so maybe I’m wrong.

Turning to the outer planets, Jupiter and Saturn have a very large number of moons each. Some of them are minute. Leda, for example, is just eight kilometres in diameter. If their orbits were visible in the sky, both systems would look larger than the moon to us. Both of them also have three “bunches” of orbits, but of the moons known from before probes were sent Saturn’s Phoebe orbits a lot further out than the rest. Nowadays a further fifty-eight moons have been discovered orbiting Saturn beyond Phoebe, making a total of eighty-three. The much more massive Jupiter only has eighty detected moons. I don’t know why this is. Both planets have large magnetospheres with tails reaching behind them and consequently Jupiter has powerful radiation belts in which three of its four planet-sized moons, as opposed to the many more smaller ones, orbit within, making them extremely hostile. Both of these magnetic fields are generated by metallic hydrogen deep within the planets.

All the outer planets have rings. However, Saturn’s, the brightest, lightest and most prominent, are likely to be temporary. This is just me again, but I think rings are more likely to develop around larger planets because they’re larger targets for objects to be captured by and then broken up.

Inside the orbit of Jupiter is of course the asteroid belt. Although it used to be thought that it was a former planet which had broken up, adding up all the matter in the belt isn’t enough to make even the smallest known planet. The largest object within the belt is Ceres, whose diameter is around 1000 kilometres. The belt is not crowded or particularly dusty, and as I’ve already said the idea that it’s a hazardous rock-strewn region is completely inaccurate. Most asteroids are so far apart from each other as to be invisible to the naked eye from their surfaces. It’s been stated that Pluto deserves to be a planet because it has quite a few moons. The asteroid belt gives the lie to this because many of its members are piles of rubble loosely held together by their weak gravity and it isn’t unusual for them to have moons simply because the smaller lumps of rock can get dislodged and start orbiting. Asteroids are made of various substances. Some, such as Vesta, are bright and icy. Others are etremely dark and made of carbon, or they may be composed of iron-nickel alloy or stone. Their orbits tend to occur fairly close together in bands due to the action of Jupiter’s gravity, which pulls asteroids with periods in certain ratios to its own sidereal period (“year”) together. Elsewhere in the system, this may have been the main factor in causing the other planets to form. The Solar System has been described as “the Sun, Jupiter and assorted débris” because of the huge disparity between the masses of the two and everything else, even added together.

One asteroid, Hidalgo, is actually a centaur and has a very unusual orbit, more like a comet. It spends some of its time in the asteroid belt but its maximum distance from the Sun is almost as far as Saturn. Its orbit is also very tilted to the plane of the planets. As far as I know, no other object is like Hidalgo.

Within the asteroid belt are the four inner planets, five if you count Cynthia. Of these, Mars and Cynthia are only about sixty percent as dense as the others. Being close to the asteroid belt, Mars has captured two small moons from it, one of which, Deimos, is unstale and will be ripped apart by tidal forces in about 30 million years, after which it will form rings. Earth and Venus, as mentioned before, are twins, although Venus is exceedingly hostile to life and the hottest planet of all on its surface (Jupiter has the hottest interior). Mercury is the smallest planet. Neither Mercury nor Venus have moons.

Also in the inner solar system is a fairly large number of asteroids which periodically impact on the planets and other bodies within it. One of these, Icarus, has an orbit taking it out to the distance of Mars and to within 20 million kilometres of the Sun. Several asteroids have orbits locked to the planets in various ways, including Amor, Apollo and Eros, also the name of classes of asteroids with similar orbits in the case of the first two. Apollo asteroids cross Earth’s orbits, so astronomers tend to want to keep an eye on them, but due to the general disengagement people seem to feel with astronomy there is no proper monitoring program for them and no organised defence against them crashing into us and wiping us all out, and apparently that’s all absolutely fine for some reason. Amor asteroids, including Eros, a sausage-shaped object about the size of the Isle of Wight, have orbits close to that of Earth’s at perihelion and usually close to Mars at aphelion. They can also be hazardous, because the orbits of relatively small bodies tend to be less stable. Finally, Aten asteroids have average distances (semi-major axes is the official term) less than Earth’s from the Sun and an aphelion greater than Earth’s perihelion, so these too cross our orbit.

Impacts on the planets of the inner system regularly chip bits of rock off them, which may land on other planets. Consequently there are occasional meteorites on Earth from Mercury, Mars and Cynthia, and there are also many meteorites originating from the asteroids.

All of the known planets of the Solar System orbit in roughly the same plane and have almost circular orbits, the biggest exception being Mercury’s, which is roughly lemon shapes without the pointy bits. There isn’t much inside the orbit of Mercury, possibly because the sunlight is so strong there that it pushes everything away from it. Some of the larger planets have asteroids orbiting 60° behind and ahead of them in the same orbits as their own because the Sun’s and their own gravity balances at those points as well as four others. This provides a kind of transport system between the different planets, because rather than having to aim for the planets themselves, spacecraft could theoretically just aim for these “Lagrangian” points where the gravity between the various bodies balances and let themselves fall the rest of the way towards the planets. All the planets orbit in the same direction but two of them spin backwards compared to the others: Uranus and Venus. Jupiter, Venus and Mercury orbit more or less upright and Uranus is tipped over. The other planets are all somewhat tilted.

The Sun is a yellow dwarf about five æons old. Although it is called a “dwarf”, it’s actually in the top ten percent of stars by mass. By volume, it’s somewhat over a million times the size of this planet.For some unknown reason, its atmosphere is more than a hundred times hotter than its surface. It has an eleven year cycle during which its magnetic fields get wound up, shifting the number and latitude of sunspots on its surface. At the end of this cycle, it kind of goes “SPLI-DOINGGG!” and the magnetic fields straighten up again.

So that’s the Solar System, about which I will be going on and on for ages, but I will also be taking breaks and only doing it every other time. I tend to think of the bodies within the system not as asteroids, centaurs, dwarf planets and planets so much as gas giants, solid round objects and smaller irregular objects, so I’ll be dealing with them as that. There are somewhere over two hundred moons, eight known planets (nine counting Cynthia), four asteroids larger than Mimas (Mimas is an important borderline case for reasons I’ll mention eventually), eighty-four Kuiper belt objects including Pluto which are larger than Mimas, and a total of 932 centaurs, all of which are too small to be properly rounded. Some of these bodies are extremely boring or very similar to other such bodies, and there are also comets of course. Obviously I’m not going to write more than a thousand blog posts on all this, but I will probably be writing quite a few.

One thing I don’t know is whether there are more Star Trek episodes than interesting Solar System objects, so we’ll have to wait and see.