Miranda heres miranda the one i said is kind of weird

[Miranda]
Here's Miranda, the one I said is kind of weird. It's got these enormous streaky features on it,
really, really huge features. This picture doesn't really do it justice, there's just an enormous
amount of irregular structure on here. The size of these things is such that to make those is
really difficult. To make such large features, you'd need enough energy that you'd blow the
moon apart. We actually think Miranda was blown apart. Something hit it that was really
massive, blew it apart, but it was just was blown apart, and its own gravity ended up bringing it
back together into a weird structure. It's got all these weird features left over from being blown
apart and reforming as a hot ball of magma.
[Neptune’s Moons]
So Neptune has a bunch of smaller moons and one big moon. The big moon is called Triton, not
to be confused with Titan, which the moon of Saturn with an atmosphere. Triton's pretty large;
it's by far the largest of all the moons. But it's very weird; it has a nitrogen atmosphere, again a
very very thin atmosphere. I think I’m showing you a picture in a few moments of that. It's got
nitrogen geysers. Its atmosphere of nitrogen is probably not stable. It should be losing that
nitrogen. It shouldn't manage to survive as air; it should actually eventually escape from the
planet. So the only reason it probably has any nitrogen is because nitrogen is coming out in
geysers, which again is also kind of weird. It also has a retrograde orbit. It's a large moon, but
it's going around backwards. Now in our Solar System, going up above the Solar System from
the North Pole, everything moves counter-clockwise in our Solar System, except for a few very
strange things, a few planets that rotate backwards; there's some small moons that orbit
backwards. This is the only large object which actually orbits backwards, and it turns out that's
not stable, in fact this moon of Triton is spiraling in; that is; closer and closer and closer to
Neptune. You might think eventually it's going to hit Neptune, but what will actually happen is
eventually it will be, because of tides, be completely ripped apart, and instead of Saturn having
© University of Waterloo and others 39

Module 5: The Solar System
Audio Transcript
the best set of rings in our Solar System, eventually (you know, give it a few hundred million
years) Neptune will have the best ring system; because Triton will just turn into a bunch of rings.
Don't buy real estate on Triton; it's not going to be there for long.
[Triton]
Here's some streaks of this wind material that's being carried out of geysers. These little streaky
things, they took pictures and saw these things moving over time, and so it was clearly little
streaks of material, and it's actually streaks of nitrogen.