round things of the solar system part four

part one

part two

part three

part four!

Back again. Last time we were with big fat Saturn with all the moons. This time we’re going to finish off the proper planets and then we can be nearly done with all this. The proper planets do not include Pluto. It genuinely isn’t really a proper planet :-(

765 million miles after Iapetus is:

uranusUranus (the planet with the name) is sometimes called an ice giant, along with Neptune, because it is full up of different ices and it has the coldest atmospheric temperature of the planets at -224.2°C. However, because it is massive, the middle is a hot sea of water, ammonia and methane and possibly because it is crazy pressurised the methane might break up into carbon that turns into diamonds that sink and melt and form a bottom ocean of liquid diamond with diamond-bergs floating on it. Uranus has a bunch of rings but it’s not Saturn so who cares.

81 thousand miles after Uranus is:

mirandaMiranda is a moon that is all smashed up. It has ridges and valleys running in different directions all over it, as well as craters and faults, that can be miles high. There are lots of detailed photos of Miranda only because Voyager 2 had to swing around Uranus in order to get to Neptune and Miranda happened to be nearby. The surface is nuts because of geological activity and squashing and stretching around between Uranus and moons and possibly because a big thing hit it and it exploded and then reformed itself.

38 thousand miles after Miranda is:

arielThis is a cool picture of Ariel in front of Uranus. Ariel is the brightest moon of Uranus and it has big crisscrossing valleys with smooth bottoms that are up to six miles deep. Because they have smooth bottoms they were most likely made by moving liquid, which would have to have been ammonia, methane or carbon monoxide because of coldness. Ariel is absorbent, possibly because tonnes of mini-meteorites hit it and worked up a fine tilth.

46 thousand miles after Ariel is:

umbrielA rocky icy block just like all the other moons around here, Umbriel is very dark though. The darkest of the Uranian moons. I failed to depict that. I also failed to depict the Wunda crater, which is very bright. No one knows why the moon is very dark with a very bright ring.

106 thousand miles after Umbriel is:

titaniaThis one is big and grey. It also has a bunch of long troughs in it, demonstrating that Titania is still tectonically active. The sun facing sides of the trough are white from going frosty in the sun.

91 thousand miles after Titania is:

oberonOberon is the most cratered major moon around Uranus. Strikes emit a bright ejecta, as on callisto, that make it quite pretty. Some craters have stuff in the bottom of them that no one knows what it is. There is a four mile high mountain on the horizon in the bottom left of this picture.

Below is an amazing video of Uranus and moons as seen by Hubble Telescope. Uranus really is as tilted as shown, it basically rolls around the sun. The video has no sound so below it I’ve put the track I was listening to when I watched it. It went pretty cool with it.

1 billion miles after Oberon is:

neptuneOne billion miles. Four and a half billion miles from the sun means the sun is pretty small here. The methane in Neptune’s atmosphere absorbs red light and makes the planet look super blue and it has lovely little white clouds drifting on the top at 832 miles per second. There are titanic storms that last years. The structure is the same as Uranus really, with the diamond sea and diamond-bergs and everything. It must be a horrendous place, these big planets are crazy unknowable balls of chemistry.

220 thousand miles after Neptune is:

tritonTriton orbits Neptune the opposite direction to the way Neptune spins. It is the only moon in the solar system that does this so it is thought that Neptune sucked it in from the Kuiper belt. The strange orbit will eventually cause Triton to break up or crash into Neptune. It is the only substantial moon that Neptune has. Triton is -235°C and it has volcanoes. Liquid nitrogen, dust and methane erupt from beneath the surface when they are heated by the sun (!) and the nitrogen condenses and settles down on the surface and makes it shiny. The surface is a dramatic mix of volcanic plains, fissures, ridges, ice caps and cantaloupe melon terrain.

That’s it. We’ve run out of planets. But there is still more solar system and there are still more round things, especially everybody’s second favourite round thing. So we’ll get back together for one last little explore in a bit.

round things of the solar system part three

Part one

Part two

Part three!

Apologies, we’ve been a while hanging out near Jupiter, here in space. I’m finally ready to get a move on though and deliver us to everybody’s favourite planet, which is of course:

400 million miles after Callisto is:

saturnSaturn is the ring-ed delight of the solar system and a big mess. Like Jupiter it is mostly gassy and like Jupiter it squashes hydrogen into a metal. Like Jupiter it probably makes diamonds from its carbon after its methane has been turned into carbon by lightning. Carbon would fall and get squashed into diamonds and then melt away in a display that would then inspire a Unilever sponsored contemporary installation for the turbine hall. The rings are over one hundred and fifty thousand miles wide and they are twenty metres thick. They are made of ice. It should really be one nice solid neat ring like what’s on the packet of che-he-heese and onion ringos or party rings but moons spoil it. There is a storm shaped like a hexagon at the top of Saturn that is as big as the Earth.

115 thousand miles after Saturn is:

mimasMimas has as much surface as Spain. It is the didiest thing to be big and round. It is made of ice like an old snowball. Whatever bashed the big dent in it nearly broke it in two, you can see cracks on the other side. Don’t feel sorry for it though, it is responsible for carving out the big gap in the big ring and ruining it.

33 thousand miles after Mimas is:

enceladusEnceladus is the nice fresh snowball. Similar sized to Mimas, it is like Mimas before Mimas was dropped in the gutter. It is pretty much the brightest thing in the solar system that isn’t the sun, reflecting nearly all of the light that touches it, which makes it terribly cold. -201° C. It gets mushed around by Saturn and it spits salty water into space, creating the e-ring of the big ring all by itself. The e-ring has organic compounds in it too, which suggests that Enceladus is the best place yet for aliens.

35 thousand miles after Enceladus is:

tethysThese next three are also balls of ice. It seems that that’s the way things are around Saturn. This one, Tethys, has a big dent like Mimas and also a big chasm. Other than that it’s basically featureless, probably due to it being a bit warm and doughy early on so that marks tended to wobble out. It is discoloured due to moving through ring pollution.

27 thousand miles after Tethys is:

dione Dione is like Tethys. However, unlike Tethys it is in cahoots with Mimas and Enceladus and they influence each others orbits. There is also a little moon, Helene, that orbits just ahead of Dione and another little moon, Polydeuces, that orbits just behind. Dione gets coated with spittle from Enceladus. Dione likes to keep friends, really. Dione has big bright scratches on it that are self-inflicted, indicative of past internal torment.

117 thousand miles after Dione is:

rheaThis one is like the other ones but its surface is more beat up. Cassini spacecraft took a picture that looks like the painting I did but I hadn’t seen that before I done it. Now it looks like I copied it. Rhea has a vague oxygen atmosphere, the only one found so far that isn’t our one. Cassini spacecraft has been flying around Saturn and its stuff for ten years doing science and taking endless amazing photos. It also does some excellent tweeting.

423 thousand miles after Rhea is:

titanTitan is the only moon in the solar system with a decent atmosphere and like Ganymede it is larger than Mercury. Cassini was designed to see through Titan’s impenetrable nitrogen atmosphere and it saw a strikingly Earth-like surface except for that the water is made from methane and the rock is made from water. Cassini also dropped the Huygens probe onto Titan which took a bunch of cool pictures and did science. Every thousand years there are storms that chuck down metres of methane.

1462 thousand miles after Titan is:

iapetusIapetus is so weird looking that loads of idiots think it was made by aliens. One half of Iapetus is very dark and the other half is very bright. No one knows quite why this is but it is probably space pollution. No one knows quite why there is a ridge most of the way around the middle of it either but the coolest explanation is that it had a ring that fell down. Iapetus also has a bunch of big dents bashed in it. It is a good moon.

That’s the end of this lot. The comedy planet is next. Hilarious, can’t wait. Here is a pretty picture of where we’ve been and here is a size comparison.

click here for part four