Noob question regarding Europa

[Fire Walk With Me]

Jupiter's moon.

http://en.wikipedia.org/wiki/Europa_moon

It says that it is believed that there is a layer of water/ice some 62 miles deep.

How did all that water come to be in a single place, so anomalous regarding the rest of the region?

[Speck Tater]

1. Comets carry LOADS of water. Nothing anomolous about it. NT

[Fire Walk With Me]

3. Comets were my first thought.

But that would take a =lot= of them, 62 miles deep across the entire area, and why then only that moon?

[Muttocracy]

2. don't know - is it a lens of water in one area, or all over the sphere at that depth? nt

[krispos42]

4. I assume you are wondering why Europa has the water on it?

That is a damn good question.

Ganymede and Callisto have water on them as well, but it's not liquid.

I would assume that Europa is close enough to get enough tidally-generated heat to keep the water partially liquid, but not so close that the heat created volcanos and such that makes the water evaporate.

[Dogmudgeon]

5. We are ALL noobs when it comes to exploring the universe

Only in the past few years have we come to realize that water is extremely common in outer space.

And here's a real kicker --

-- most of it has a whole bunch af sodium mixed in.

It's seawater in space.

--p!
Surf's up!

[mainegreen]

6. Do you mean water, the element or liquid water.

If you mean water, the element, then it's not anomolous. Hell, a lot of the outer moons and planets have tons of water.

If you mean water as a liquid, that is a good question. Perhaps it's there for fishing?

[Fire Walk With Me]

7. Okay then, do Callisto and the other moons have anything approaching Europas

and is Europa still an immense anomaly in these regards?

[TechBear_Seattle]

8. Not quite, but Callisto and Ganymede do have a lot of ice

In the Wikipedia article on the Galilean moons,

Ganymede is composed of silicate rock and water ice, with an ice crust floating over a warmer ice mantle. The metallic core of Ganymede suggests a greater heat at some time in Ganymede's past than had previously been proposed. The surface of Ganymede is a mix of two types of terrain – highly cratered dark regions and younger, but still ancient, regions with a large array of grooves and ridges. Ganymede has a high number of craters, but many are gone or barely visible due to Ganymede’s icy crust forming over them. A small oxygen atmosphere is present on Ganymede.

and

This moon’s (Callisto) surface lies above a layer of ice, which is 150 kilometers thick, and a layer of water, which is ten kilometers thick.

All in all, water is pretty common in our solar system. In addition to Earth and the Galilean sattelites, all of Saturn's larger moons have large deposits of water ice, and Saturn's rings are in large part water ice. Water vapor has been detected in the atmospheres of every planet, including Mercury (which, oddly enough, has more than does Venus.)

Europa has the largest proportion of water to total mass in the Solar System, I believe. But then, some body has to be at the top of such a list.

[Fire Walk With Me]

9. Thanks for the facts!