Many a moon
Mar. 27th, 2026 10:15 am![[personal profile]](https://www.dreamwidth.org/img/silk/identity/user.png){kind=small}
baroque_mongooseI haven't said a lot about my studies lately because they did get rather messed about. My mother being ill was obviously stressful (from October we didn't know how long she was going to last, but we knew it wouldn't be too long), and of course I wasn't well myself for most of December; so what happened with this module was that I got off to a terrific start, then didn't do much for quite a while because it was so hard to concentrate, then got back into gear and am now motoring along with it. It's really just as well it's not a maths module this time, as those tend to require much more sustained effort, whereas with this one as long as you get the assignments in on time (and I did have to have one extension in February, when the Mum-related stress was particularly bad) you can do everything else whenever you like.
Being back in gear, however, is very satisfying. I have just finished a short course called "Moons of our Solar System", which you can, if you wish, find here: https://www.open.edu/openlearn/science-maths-technology/moons-our-solar-system/content-section-overview?active-tab=description-tab Most of these short OpenLearn courses have been excellent, but this one has been so far the best of a very fine bunch. I have enjoyed it immensely, and if you have any interest at all in planetary moons, including our own Moon, this one is for you. It's free, it's nominally 24 hours (though it probably won't take you as long as that, even though it's quite video-heavy, unless you delve into all the extra bonus material, of which there is a lot), and you get a badge at the end to show that you've passed it. And it is a whole lot of fun.
Obviously, there is a fair bit about our own Moon; after all, so far it's the only moon in the solar system where we've managed to land anyone. But there's plenty about all the others too. Every major moon in the system is covered, along with several of the more interesting minor ones. (Did you know some asteroids have moons? I didn't; but there it was, a photo of the asteroid Ida and its tiny moon Dactyl.) I knew Europa probably had an ocean of liquid water under its frozen crust, but I didn't realise it's not alone in that respect. A number of other moons of Jupiter and Saturn probably also do. I learnt all about tidal heating, which is the reason many of the outer moons aren't totally frozen; it's probably also what powers the huge amount of vulcanism on Io. (You like active volcanoes? Io is your dream destination. It's covered in them.) I also learnt about cryovulcanism, which happens on worlds where the rock is primarily water ice with an admixture of other ices, and the "magma" is mainly liquid water. I learnt about different types of terrain and how they were probably formed.
And then, of course, there's my favourite moon of all. Titan. I just love Titan, so I already knew a fair bit about it, but I still learnt some new things. Titan is one of Saturn's moons, and the only moon in the solar system with a dense atmosphere (indeed, the atmospheric pressure on Titan is about 1.5 times that on Earth). This atmosphere is about 97% nitrogen, but that other 3% mainly consists of hydrocarbons, predominantly methane and ethane, so you have smog, basically. You can't see the surface of Titan through the atmosphere - it took the Cassini spacecraft and the Huygens probe to do that. Titan is so cold that methane (with a bit of ethane) does exactly what water does on Earth; so there are rivers and lakes on Titan, and it rains, and it's even possible there may be lightning. I mean... that's wild. Not only that, but due to Titan's unique combination of dense atmosphere and low gravity, if you wore a suitably insulated bat-suit you could fly there under your own power. What is not to like here?
It's not all text and videos, either, no matter how informative. You can play Moon Trumps, too. (Do not put that in a search engine. You'll just get images of an obnoxious politician superimposed on a lunar background talking about how he wants the Moon, pretty much.) Moon Trumps is a card game devised by the OU; for some reason, the first time it's linked in the course, the link doesn't work, but the second time it does. You play against the computer, though I have to say I'd love a set of actual cards. The way it works is that each card has a photo of a different moon (some well known, some very obscure), together with some data: size (I think in terms of diameter), density, orbital period, and orbital radius. You pick a card at random and then choose one of the data points about your moon; so, if you got our Moon, that's pretty big, so you'd generally be safe selecting the size. If the data point you've chosen is larger than the corresponding one on the card your opponent picked, you win both cards (unless it's orbital period, when the smaller one wins). Otherwise, your opponent wins the cards. It's a good game and you learn quite a lot by playing it.
I reckon today it'll probably be more astronomy (White Dwarfs and Neutron Stars, anyone?). But I suspect that whatever course I do, it'll have a hard time beating that one.
Being back in gear, however, is very satisfying. I have just finished a short course called "Moons of our Solar System", which you can, if you wish, find here: https://www.open.edu/openlearn/science-maths-technology/moons-our-solar-system/content-section-overview?active-tab=description-tab Most of these short OpenLearn courses have been excellent, but this one has been so far the best of a very fine bunch. I have enjoyed it immensely, and if you have any interest at all in planetary moons, including our own Moon, this one is for you. It's free, it's nominally 24 hours (though it probably won't take you as long as that, even though it's quite video-heavy, unless you delve into all the extra bonus material, of which there is a lot), and you get a badge at the end to show that you've passed it. And it is a whole lot of fun.
Obviously, there is a fair bit about our own Moon; after all, so far it's the only moon in the solar system where we've managed to land anyone. But there's plenty about all the others too. Every major moon in the system is covered, along with several of the more interesting minor ones. (Did you know some asteroids have moons? I didn't; but there it was, a photo of the asteroid Ida and its tiny moon Dactyl.) I knew Europa probably had an ocean of liquid water under its frozen crust, but I didn't realise it's not alone in that respect. A number of other moons of Jupiter and Saturn probably also do. I learnt all about tidal heating, which is the reason many of the outer moons aren't totally frozen; it's probably also what powers the huge amount of vulcanism on Io. (You like active volcanoes? Io is your dream destination. It's covered in them.) I also learnt about cryovulcanism, which happens on worlds where the rock is primarily water ice with an admixture of other ices, and the "magma" is mainly liquid water. I learnt about different types of terrain and how they were probably formed.
And then, of course, there's my favourite moon of all. Titan. I just love Titan, so I already knew a fair bit about it, but I still learnt some new things. Titan is one of Saturn's moons, and the only moon in the solar system with a dense atmosphere (indeed, the atmospheric pressure on Titan is about 1.5 times that on Earth). This atmosphere is about 97% nitrogen, but that other 3% mainly consists of hydrocarbons, predominantly methane and ethane, so you have smog, basically. You can't see the surface of Titan through the atmosphere - it took the Cassini spacecraft and the Huygens probe to do that. Titan is so cold that methane (with a bit of ethane) does exactly what water does on Earth; so there are rivers and lakes on Titan, and it rains, and it's even possible there may be lightning. I mean... that's wild. Not only that, but due to Titan's unique combination of dense atmosphere and low gravity, if you wore a suitably insulated bat-suit you could fly there under your own power. What is not to like here?
It's not all text and videos, either, no matter how informative. You can play Moon Trumps, too. (Do not put that in a search engine. You'll just get images of an obnoxious politician superimposed on a lunar background talking about how he wants the Moon, pretty much.) Moon Trumps is a card game devised by the OU; for some reason, the first time it's linked in the course, the link doesn't work, but the second time it does. You play against the computer, though I have to say I'd love a set of actual cards. The way it works is that each card has a photo of a different moon (some well known, some very obscure), together with some data: size (I think in terms of diameter), density, orbital period, and orbital radius. You pick a card at random and then choose one of the data points about your moon; so, if you got our Moon, that's pretty big, so you'd generally be safe selecting the size. If the data point you've chosen is larger than the corresponding one on the card your opponent picked, you win both cards (unless it's orbital period, when the smaller one wins). Otherwise, your opponent wins the cards. It's a good game and you learn quite a lot by playing it.
I reckon today it'll probably be more astronomy (White Dwarfs and Neutron Stars, anyone?). But I suspect that whatever course I do, it'll have a hard time beating that one.
