Astronomy on Titan: the Solar System and Beyond

When the Sun gets eclipsed, one can observe four objects near it: Mercury, Venus, the Earth, and Mars. Over an eclipse season, one can observe them go back and forth around the Sun, evidently orbiting it.

Moving about as fast as the Sun, and looking like a bright star, would be Jupiter. It would get as far as 33d from the Sun, making it easier to see than the inner planets.

Looking with a telescope will reveal the Earth’s moon and Jupiter’s four big moons. One will quickly find that those four moons follow Kepler’s third law. As to the inner planets, Jupiter, and Saturn, if their motions are referred to the stars, then they will also obey that law. So we notice these sets of objects all obeying it:

  • Saturn’s moons
  • Jupiter’s moons
  • The Sun’s “moons”

So if one wasn’t sure of Kepler’s third law before, one would be sure of it now.

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Astronomy on Titan: the Saturn system

So once we are floating in a balloon atop Titan’s haze, we will get to see lots of interesting things. I will start with the Saturn system.

Saturn is an obvious place to start, because of its prominence. Its angular size is about that of a fist at arm’s length, much greater than anything else that one will see in its system. We will be able to see its atmospheric zones and belts, and near its poles, its auroras. We will also notice that it is flattened at the poles, with its flattening being about 1/10.

Saturn’s rings will also be visible, though even at their best visibility, they will be very close to being edge-on, and one may need a telescope to resolve them.

Several of Saturn’s moons will be visible to the unaided eye, and one will also see some of them being eclipsed by Saturn and some of them casting shadows on Saturn. It will take a telescope to resolve them, with only Rhea being even borderline resolvable without a telescope.

There are lots of interesting things that one can discover by observing them.

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