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Saturn

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The following questions were answered by astronomer Dr. Cathy Imhoff of the Space Telescope Science Institute.

How big is Saturn?
Saturn is about ten times bigger across than Earth. But it weighs 95 times what the Earth would weigh — if you could find a scale big enough to put it on!!

How far away from Earth is Saturn?
Saturn is about ten times farther from Earth than the sun. That's about one BILLION miles.

How bright is Saturn?
As you may know Saturn shines by reflecting the light of the sun. It looks as bright as one of the brightest stars in the sky.

What is Saturn's surface temperature?
Saturn's surface (well, its clouds) is quite cold, about -288° Fahrenheit. That is because it is so far from the sun.

What is Saturn's tilt?
Saturn is tilted with respect to its orbit around the sun almost the same amount as Earth. Saturn is tilted 27 degrees, and the Earth is tilted 23 degrees. That means that Saturn has seasons (like winter and summer) like Earth. Of course it is very different from Earth, too — it is big, cold, and shrouded in clouds!

Why is Saturn so cloudy?
Saturn, as you know, is one of the giant outer planets that are mostly gas instead of rocky like Earth. The other giant gas planets are Jupiter, Uranus, and Neptune. Here is why we think they are mostly gaseous:

All the planets formed from a disk of gas and dust that surrounded the baby sun. The gas was mostly hydrogen, with some helium, nitrogen, oxygen, and so forth. So when the planets formed, they had both rocky material (from the dust) and gas. But the planets closest to the sun couldn't hold on to most of their gas. The sun was too hot and blows out too hard, so the gas was mostly blown away. But the giant outer planets were bigger and farther from the sun, so they were able to hang on to their gases.

How did Saturn get its rings?
We think that a small moon got too close to Saturn and was torn apart by Saturn's gravity. It is also possible that an asteroid passing by Saturn hit into one of the moons.

How many rings are there in Saturn?
When we look at Saturn's rings from Earth, they appear to have various bands. They have been given names: A, B, C, D, E, F, and G (there are seven bands). But the rings are actually made up of zillions of bits of rock, some as big as boulders but most tiny like sand. They are all in orbit around Saturn, like a horde of tiny moons.

Why does Saturn have so many rings?
Saturn's rings are made up of zillions of rocks. A few are as big as cars but most are small as sand. They all circle Saturn like zillions of little moons. So they look like rings but actually they are lots of tiny moons!

Are Saturn's rings made up of huge chunks of rocks and ice or small chunks of ice?
Saturn's rings are made up mostly of ice with a little rocky stuff mixed in. The chunks are mostly small, from around an inch across to 15 feet, with a few bigger "icebergs." Okay, small is relative — the chunks are much smaller than a moon but big enough that you wouldn't want to have one smack into your spaceship!

Are Saturn's rings formed by comets?
We aren't completely sure how the rings formed. But we think that they are from a comet or a moon that got too close to the planet and broke up. The rings contain both rocky and icy material, so maybe it was a comet. If the comet that hit Jupiter had not hit it but gone into orbit around the planet, maybe it would have made rings like Saturn's.

What gases can be found on Saturn?
Much of the atmosphere of Saturn is made of hydrogen and helium, but there is also water vapor, methane, ammonia, and nitrogen.

Can we land on Saturn?
Well, Saturn (and the other giant gas planets) is almost entirely made of gases — mostly hydrogen, helium, and methane. The atmosphere gets pretty thick, so it would probably seem more like an ocean than an atmosphere. You couldn't land and walk around, but you could either "fly" through the outer atmosphere with a spacecraft built like an airplane or "swim" through the deeper layers with a spacecraft built like a submarine.

Why is one part of Saturn hotter than the other?
I'm not sure which part you mean. Just as on Earth, the north and south poles are colder than the equator. And the night side is colder than the day side.

What is the distinction between satellites and moons? 
Normally moons and satellites mean the same thing. On Earth, though, if we counted the man-made satellites, we would have to say that we have many more than just one "moon!" I think that we are all having a hard time keeping up with how many moons Jupiter and Saturn have. (Editor's note: As of 2014, Saturn has 53 natural satellites, also known as moons, and nine provisional moons, or moons that need to be confirmed by the International Astronomical Union.)

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    Astronomy and Space, Planets, Moons, Solar Systems, Real-World Science, Science through Literature
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