Complete Science Data Of Galileo Probe Mission? Options

[Dominik]

Hello there.

I've got a question about the science data of the galileo probe mission (Plunge into jupiters atmosphere).

Is it possible to download the complete dataset of the mission? If yes, where can I find those data? I've tried to find them with google, but I found nothing.

Thx for help...

(Sorry for my bad english. I don't use it so often, because I'm from germany )

[djellison]

Feasable perhaps, but fairly pointless I'd have thought. You know that bit on a plane flight when you're going thru the clouds and you cant see the end of the wing.....

That - plus the bandwidth from probe-to-orbiter was fairly poor I'd imagine, much like Huygens was.

Doug

[Dominik]

...the bandwidth from probe-to-orbiter was fairly poor I'd imagine, much like Huygens was.

3.8 Megabit of data was collected. Mostly scientific data from jupiters atmosphere. But I've seen some pictures from the galileo probe mission on TV some years ago. Those pictures were from the cloud structures (Below cloud top). They looked like radar pictures, but the probe did not have a radar.

Thanks for the link djellison. That is, what I was searching for.

[JRehling]

3.8 Megabit of data was collected. Mostly scientific data from jupiters atmosphere. But I've seen some pictures from the galileo probe mission on TV some years ago. Those pictures were from the cloud structures (Below cloud top). They looked like radar pictures, but the probe did not have a radar. 

Thanks for the link djellison. That is, what I was searching for.

The subcloud "pictures" I think you are referring to were reconstructed images based on models made from the Galileo *Orbiter*. Images made in different methane bands bring out detail from different depths. Those "visualizations" assumed that the clouds form three discrete thin sheets with clear air between them. Then they were colored. You can see lots of them here:

http://www2.jpl.nasa.gov/galileo/sepo/atju...s/latitude.html

A descent probe into Jupiter has such limited bandwidth opportunity, and such limited payload mass, with such uncertain prospects for seeing *anything* that it is hard to rationalize a camera. The Galileo Probe instrument payload was about 25 kg or a bit more than that. Huygens's camera was 8.5 kg -- what third of Galileo's payload would you have gotten rid of to get what might be one or two totally featureless pictures, and even in a good case might have looked like BW pictures of terrestrial cumulus clouds?

[DDAVIS]

A descent probe into Jupiter has such limited bandwidth opportunity, and such limited payload mass, with such uncertain prospects for seeing *anything* that it is hard to rationalize a camera. The Galileo Probe instrument payload was about 25 kg or a bit more than that. Huygens's camera was 8.5 kg -- what third of Galileo's payload would you have gotten rid of to get what might be one or two totally featureless pictures, and even in a good case might have looked like BW pictures of terrestrial cumulus clouds?

Well, future probes may well have better data bandwidth than what you are used to. I don't see uncertainty about what a camera would see as good reason to assume a camera isn't desirable.

this may be apocrophal but I recall in my USGS days hearing talk about a debate on whether the Pioneer F abd G spacecraft should have any imaging capability at all, after all, what could possibly be interesting about cloud tops? As it was the imaging Photopolerimeter was a cheap crappy substitute for a camera which was better than nothing, but outclassed by the real cameras the Voyagerws later carried.

Don

[ljk4-1]

this may be apocrophal but I recall in my USGS days hearing talk about a debate on whether the Pioneer F abd G spacecraft should have any imaging capability at all, after all, what could possibly be interesting about cloud tops? As it was the imaging Photopolerimeter was a cheap crappy substitute for a camera which was better than nothing, but outclassed by the real cameras the Voyagerws later carried.

  Don

They also assumed the Mercury astronauts wouldn't want to look out a window of their spacecraft, either.

Nothing sells space exploration like optical images.

As for a camera on an Jupiter atmosphere probe, how about an infrared one for cutting through the haze and clouds?

[um3k]

As for a camera on an Jupiter atmosphere probe, how about an infrared one for cutting through the haze and clouds?

But then what would there be to look at?

[mike]

But then what would there be to look at?

Who knows. That's the idea, to find out what is under there. Maybe nothing, probably something. I'm not knowledgeable on whether it's possible to have an IR probe that cuts through cloud and haze but bounces off of more solid matter, but the basic idea makes sense, RADAR or whatever.

Surely you agree that gravity causes things to coalesce, and that therefore if Jupiter is gas so far away from the core, the (massive) core must be rather more dense?

[JRehling]

Who knows.  That's the idea, to find out what is under there.  Maybe nothing, probably something.  I'm not knowledgeable on whether it's possible to have an IR probe that cuts through cloud and haze but bounces off of more solid matter, but the basic idea makes sense, RADAR or whatever.

Surely you agree that gravity causes things to coalesce, and that therefore if Jupiter is gas so far away from the core, the (massive) core must be rather more dense?

There should be no doubt that Jupiter has interesting "stuff" in its depths, but probing it from point-blank electromagnetic sensing (IR, microwave, radar, whatever) may not perform particular explorations the way we wish.

It is very unlikely that *any* EM sensing will penetrate more than a small fraction of the planet's depth. A few thousand km of air will still block light. We'd likely see an isotropic (ie, blank) field in most any wavelength. Exceptions would be:

1) Thermal wavelengths: We could see heat and cooling in updrafts, but really this sort of thing is more appropriately done from orbit. The intricacy of the structure of such updrafts and downdrafts is unlikely to be featured well from inside the atmosphere. You might see one or two "features" in the immediate vicinity, but if the atmosphere is heterogeneous in this respect, you wouldn't see very much, very far.

2) Unusual "clouds", deeper down, of compounds that we don't think of as volatiles. There could be sulfur, or even iron (etc) clouds at great depth. I don't know -- possibly a probe could go deep enough to radar scan for those? The feasability is questionable.

[mike]

It is very unlikely that *any* EM sensing will penetrate more than a small fraction of the planet's depth. A few thousand km of air will still block light. We'd likely see an isotropic (ie, blank) field in most any wavelength.

That doesn't seem fair, to have a huge ball of matter floating nearby and no way to examine most of it. Surely there's some way to take a look, perhaps with methods we haven't yet discovered/devised.. Maybe Jupiter will just have to wait a while.

I'd personally like to see a camera-equipped probe descend into Jupiter, just because the pictures would be utterly unique if nothing else - even if they are just undifferentiable walls of white, they're undifferentiable walls of white from Jupiter. We'd have to see something, and I think that something would be worth the effort. I'll pony up the $300 kajillion myself. If that's not enough, we can use some of that 'blowing people up' money of which we possess so much...

[JRehling]

That doesn't seem fair, to have a huge ball of matter floating nearby and no way to examine most of it.  Surely there's some way to take a look, perhaps with methods we haven't yet discovered/devised..  Maybe Jupiter will just have to wait a while.

I would liken the problem to seeing the core of the Earth. Can't be done. The only two ways to probe that are with thumps and gravity. Sensing the gravitational field is part of the Juno mission, so look forward to it! Thumping a gas is harder than thumping a solid. I suppose we could "sound" Jupiter by setting off a hydrogen bomb and listening for the sound reflection at a second site, separated by some fraction of Jupiter's circumference away. If we had the capability, it would be ideal to have a probe (or more than one!) listening at the same time as another comet hits the planet, but those events are few and far between. You can't really count on an entry probe being timed precisely enough (the margins are very tight), so a dirigible would be necessary. Maybe a long-lived nuclear powered hot air balloon would be possible -- but the hazards are innumerable. Remember that Jupiter's atmosphere has a tiny molecular weight (lower than helium!), so that only heated H2 could float in it, and provide meager buoyancy per volume of balloon.

Once you had something long-lived, a camera would seem a lot more worthwhile, as the high probability of getting a bland image would eventually give way to a good side-looking shot of a cloud formation. But it would still have to fit into the mass margins of what would have to be a small payload once you had a balloon big enough to loft a nuclear reactor, and this large and therefore flimsy balloon would have to face incredible wind shear sooner or later. I don't know if it's even possible to hope for a lifespan beyond hours. Surviving one rotation of the planet would be fantastic.

Given another comet strike with enough advance warning, we could hope to plop a dirigible or two in there and get the sounding data, maybe even several distinct ones if the impactor is fragmented like Shoemaker-Levy was. Nature is not forced to cooperate with this plan, however, which is already baroque.

I'd personally like to see a camera-equipped probe descend into Jupiter, just because the pictures would be utterly unique if nothing else - even if they are just undifferentiable walls of white, they're undifferentiable walls of white from Jupiter.  We'd have to see something, and I think that something would be worth the effort.  I'll pony up the $300 kajillion myself.  If that's not enough, we can use some of that 'blowing people up' money of which we possess so much...

You can pretend these are from Jupiter:

http://www.backgroundcity.com/groups/g7.html

[David]

You can't really count on an entry probe being timed precisely enough (the margins are very tight), so a dirigible would be necessary. Maybe a long-lived nuclear powered hot air balloon would be possible -- but the hazards are innumerable. Remember that Jupiter's atmosphere has a tiny molecular weight (lower than helium!), so that only heated H2 could float in it, and provide meager buoyancy per volume of balloon.

And given that, at Jupiter's cloudtops, everything weighs more than two and a half times what it does no earth, you'd need something extraordinarily light. The task might be more practical on Saturn, where the gravity is less than earth's.

Once you had something long-lived, a camera would seem a lot more worthwhile, as the high probability of getting a bland image would eventually give way to a good side-looking shot of a cloud formation.

I wouldn't expect that an entry-probe with an imager would provide very spectacular images from inside the clouds (though I'd be happy to be wrong); but if one had a downward-pointing camera, you could get invaluable images from the approach to the cloudtops, at much higher resolution than anything we have now, something like the approach images from Titan. Obviously they'd be more interesting if you dropped the probe into a raging storm, instead of a bland cloud-band!