Moons of our Solar System
Moons of our Solar System

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Moons of our Solar System

Week 7: Exploring moons


Find out about the missions that gave us our first close-up views of distant moons: Voyagers 1 and 2, Galileo and Cassini-Huygens. Learn why probes are crashed into giant planets rather than risk crashing into a moon.

Here Jess reflects on the past three weeks and then introduces the missions that have taught us most about other moons. Windsurfing on Titan anyone?

Please note that when Jess refers to Titan as ‘the only moon in the Solar System with an atmosphere’ she should have said that it is the only one with a ‘dense atmosphere’.

Download this video clip.Video player: moons_1_vid051.mp4
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Well, that was quite a lot to learn about our Moon. The fascinating challenge with our Moon is that the more we find out about it-- with new techniques and new missions-- the more we understand its relationship with the Earth, and the more we realise how much there is still to learn. This is a good thing to bear in mind this week, when we'll be learning about other moons.
Some of our descriptions may be incomplete. And some of our interpretations we're still trying to confirm as fact. But as I said last week, science advances by continually testing hypotheses.
We'll begin by learning about the four great missions that taught us most of what we know about the moons of the outer planets- the two Voyager probes that flew past Jupiter, Saturn, Uranus, and Neptune; the Galileo probe that made an orbital tour of the Jupiter system; and Cassini, that reached Saturn in 2004 and is still producing great results.
Next, we'll look at Titan as seen from multiple flybys by Cassini and from the surface by the Huygens probe, a parachute lander delivered by Cassini. Interestingly, you could go windsurfing on Titan. It is the only moon in the Solar System with an atmosphere- and its atmosphere is dense with winds. It also has vast lakes. But you'd need a pretty good dry suit. The lakes are liquid methane, and it's pretty cold.
We'll end the week with a look at some particularly notable other moons, including some moons of Uranus where there are places where it seems cryovolcanic flows made of a rather gooey mix of water and ammonia have oozed onto the surface. See you next week.
End transcript
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By the end of this week, you will have an understanding of:

  • the missions that have explored moons in the outer Solar System
  • the surface and atmosphere of Titan
  • some medium-sized icy moons.

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