Galileo's Flyby of Almathea

An anonymous reader writes "The spectacular Galileo flybys of Jupiter, Europa and Io are largely credited with the discovery of frozen water ice and some of the earliest examples of non-solar (tidal) heating anywhere in our solar system. For the next 10 days, Galileo scientists are preparing for their next target: probing one of Jupiter's moons, Almathea, at the close-up range of 100 miles. Almathea is one of the most unusual moons in the solar system, because it gives off more heat than it receives from the Sun."

Shift the focus already

[Drunken Coward]

Spending all these resources investigation such distant objects in outer space when there is so much [slashdot.org] so close [slashdot.org] to us that we have yet to get a good view of. Walk before we run people!

For those looking for Earth like planets...

[MrFenty]

This sort of place is exactly the sort of reason I think, if we find life elsewhere in the universe (intelligent or otherwise) then it won't have to be on a planet that looks exactly like Earth and at roughly 1 AU from its local star. Here we have a moon that gives off heat, at a very large distance from its sun. There is no reason for us to be arrogant enough to assume that life can only exist on a place that looks identical to our place. This really bugs me, when I see people say "life can't exist there, that planet is twice Earth's distance from its star..." and rubbish like that. Aarrgghh !

Sorry, I needed that rant.

Looking at Jupiter and its moons

[igotmybfg]

Two summers ago, one of my friends in University here asked me to come outside with her and look at something which she described as 'cool'. Thinking I might get some :) I went with her, and we set up a tripod and telescope and ended up watching the stars all night long. For a time we focused on Jupiter, and though I couldn't see Almathea, I did see Jupiter, Callisto, Io, Europa, and Ganymede. The thought that there was nothing (well, almost nothing) in between me and those huge, huge objects that were so very far away still sends tingling down my spine whenever I think about it. It reminds me, when I think that there is pretty much nothing left to do or discover, that there is indeed a whole universe out there, waiting for (or perhaps indifferent to) us.

Cheers!

Re:Shift the focus already

[Blackneto]

Um, Galileo has been orbiting Jupiter for 7 years. It's not like it's costing them a lot more to do this.
Think and read before we post people!

Re:Shift the focus already

[ChuckDivine]

While I strongly support looking for close in objects, it's not like it's an either/or situation. The world has lots of astronomers (and other kinds of scientists as well). We also have resources sufficient to do research into a wide variety of astronomical phenomena.

Those of us who have actually done some political work in support of looking for earth approaching asteroids only ask for a few millions of dollars to finance such work. Focusing all of our attention on nearby objects would be foolish and wasteful in the extreme.

Re:For those looking for Earth like planets...

[aurelian]

Planet hunters don't assume that life can only exist on earth-like planets. However they do assume that life might be more likely to be found on earth-like planets. hence it's worth looking for them.

Re:Leaves me feeling depressed...

[raduga]

With the primary arial undeployed the primary effect has been a reduction in the total number of pictures, and the frequency at which they are captured and returned; since the low-gain antenna / tape recorder are still capable of bringing back images of the same quality, just not nearly as many.

It's disappointing, sure, but even had the arial been fully deployed, we wouldn't have significantly greater resolution, and might not see substantially more detail of Europa's surface. Also, the change in mission priorities might (?) have meant fewer resources spent on magnetometric observations. Events don't seem to change frequently enough on Europa's surface that a few missing frames would have changed our view much.

(Contrast with Io! What if we'd missed that eruption?)

Re:Jupiter's mass is the cause of the heating

[pogen]

some think it's actually a star that just wasn't big enough to have it's own mass crush it's innards to the point where nuclear fusion occurs and the star is born.

And that makes it "actually a star" how, exactly?

You pretty much just gave the definition for why it isn't a star.

Re:Gives out more heat that it recieves.

[mpe]

I think at least Io was so volcanic and active because of the extreme "tidal waves" from Jupiter. The "waves" are, due to the huge gravitation of Jupiter, so strong they pull solid matter and this of course cause quite a bit of friction. And friction cause heat. Not really surprising, since such a small object as our Moon does funny things to our seas. :-)

IIRC Io being heated is part of an interaction with the other Jovian moons. What happens is that a moon generating tides also transfers energy to the moon, so that it moves away from the planet it orbits. This is what happens here on Earth.
With Io the interaction of the other large moons keeps in in orbit, so the energy shows up as vulcanism.