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Galileo's Final Blaze of Glory
EccentricAnomaly writes: "CNN reports that the Galileo spacecraft is about to perform its last flyby of Io. Galileo will skim a mere 100 km above Io to enter a trajectory that crashes into Jupiter in 2003. This is to avoid the spacecraft running out of fuel and accidentally crashing into Europa which might contaminate it with any bacteria spores on Galileo. This is a real concern - Apollo 12 found bacteria on Surveyor 3 that survived two and a half years on the moon."
I just wish mankind could be this careful with its native planet.
(mod me as you will...)
Sorry, couldn't help myself:
All these worlds are yours - except Europa. Attempt no landings there.
(This should be all caps, damn the lameness filter!)
This is the place where you write something that will make you seem like a complete idiot.
We were warned not to touch Europa.
but I always am surprised when I hear these stories of how long bacteria can survive outside of normal conditions. 31 months on the moon, 4800 years in peruvian pyramids, 11000 years in a dead mastodon (extinct mammal sort of like an elephant), and (mabye) 300 million years in coal!
He who defends everything, defends nothing. -- Fredrick The Great
..has a lot more chances to survive on Europa which has Ice and presumably water. If you have read you Arthur C. Clarke you'd know that Jupiter is an "unlit" star so it's better suited to kill any leftover bacteria.
$HOME is where the
-- silver_p
What I don't understand from this theory is how bacteria can survive the reentry pressure and especially heat that is generated! Or does the inside of a big enough asteroid stay cool? I wouldn't think so but does anybody have a definitive answer?
Imperium et libertas
Autocracy and freedom
Jupiter has no solid surface, It is a gas giant. Technicaly it is a Brown Dwarf- which is a star that never got large enough to start a fusion chain reaction. It is extremely unlikely that any sentient life could form there, especialy considering the gravity is strong enough to compress the hydrogen atmosphere into a liquid metal at it's core, which produces the strongest magnetic field in the solar system.
Europa, on the other hand, has everything life needs to flourish. Water- most likely in a huge ocean under the surface ice, and energy- mainly geothermic energy produced by the mammoth gravitational force exerted by jupiter (the same ones that make io the most volcanicly active body in the solar system), as well as a phenominal amount of magnetic flux produced by hydrogens metalic core.
Now if you ask me, I'd prefer to burn a probe up in a dead star then a moon which could possibly support life.
is if jupiters magnetic field created a wormhole to a few billion years ago, and we sent a probe through which had a small amount of bacteria in it. It then lands on earth, and over the next few billion years ends up evolving into Humans...... what a paradox. What came first? the human or the probe ;-). Oh dear... my heads starting to hurt.
(Ok Ok I know... but I've just finished watching the new Planet of the Apes movie)
I found a fact sheet about this little rock. Looks kinda like the asteroid phobos. (We made a non-crash landing on phobos, but I never heard if they took off again)
More importantly, there are plans being drawn up to send probes to Europa to look for eveidence of life, as it's one of the most likely candidates in the solar system.
If there is any bacteria on the galileo probe, then crashing it on Europa risks contaminating any samples that we do take, thus giving false positives. Not cool given the amount of time, effort and money that will go into such a mission. (Don't even get me started on what a blow it would be for science...)
Cheers,
Tim
It's official. Most of you are morons.
We can strip mine the rest later...
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From: drizva@spacedefence.jupiter
To: pcachvoorsnrt@spacedefense.mars
Dear colleague,
We have recently become aware that those naughty Earthlings from the third planet are planning yet another attack on the solar system.
As you are well aware, those nasty Earth people have sent a number of projectiles slamming into your peaceful planet over the last few solar cycles. These atacks have become more sophisticated and have been increasing in numbers over time.
It now appears that a nuclear armed projectile that has been spying on our planetary system will be sent plunging into our atmosphere. The consequences of this act are grave and disturbing to say the least.
As a result of this latest attack, please be advised that we will be redirecting several asteroids from the main artillary field located between our two planets past your peaceful red planet toward the third planet in order to send a firm message to the Earthlings.
You will be happy to learn that once we have obliterated the Earth, you will then have an unobscured view of Venus.
Best Regards,
Drizva
In 1919, my father and Roy Adams, were 10 years old. My grandmother gave my father a small lathe which he and Roy used to fabricate a small, air-powered, motor. The motor is amazing, especially given that it was designed and built by two 10 year olds.
Roy's parents were poor so he didn't get to go college. However, he was so self-evidently bright, it didn't matter. JPL eventually hired him and he ended his career as a project manager on the Galileo. My father always got a kick out of the fact that Roy, with his high school diploma, had a raft of rocket science Ph.D.'s reporting to him.
The little air-powered motor still works. It, like the Galileo, way outlived its intended design life. Rest In Peace Roy, you did good.
If we're already spending millions of dollars on these machines, why don't we simply send em off into space in any direction taking pictures and mapping god-knows-what, then transmitting back to us until rapture? After the initial delay of sending the first image back to us, we would be getting a fairly consistent stream of images...at least until some object comes between, the signal strength wanes, or it crashes into something else (which is what it's doing now). Even the most focused spray of transmission back to us would do since as it gets further away, its transmit area would eventually cover our entire path through the solar system so that we wouldn't miss an image. I had a professor once that would probably say, "We never bring these billion-dollar toys back because those fascist, propagandizing bastards never sent em in the first place!"
Tidal stresses, such as the ones that drive the volcanos on Io, may produce enough heat to produce liquid water under the surface of Europa. And all you need is heat, hydrogen, and CO2 to have life.
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...we want to be sure it is native to Europa, not imported from earth by accident in a previous space mission. This is simply good science, nothing else, and is completely orthogonal to how well, or how poorly, we are acting as stewards of the Earth.
So get off your high horse and get over yourself, saving the whales and turning our backs on technology (I notice you are using a computer, including all kinds of hydrocarbon-generated electricity and toxic materials used, and dumped, in the creation of its components) to "save the earth" really has nothing whatsoever to do with Galileo's final trajectory past Io.
The Future of Human Evolution: Autonomy
..we want to be sure it is native to Europa, not imported from earth by accident in a previous space mission. This is simply good science, nothing else, and is completely orthogonal to how well, or how poorly, we are acting as stewards of the Earth.
Certainly, the major reason for going out of our way to avoid Europa is as you say (to avoid potentially introducing life where it did not exist before.) However, I would submit that it is also "good science" to ensure that a nuclear-powered spacecraft does not crash on and contaminate a terrestrial body suspected of harboring life. This is not "save the whales environmentalism"; it is common sense. Certainly you would not call a person who was opposed to detonating a nuclear device in the atmosphere on Earth to be a "save the whales" environmentalist?
We're going down, in a spiral to the ground
The large ablative surface area is to help dissipate the reentry heat, not a cause of it. It's been a while since I looked at this, but I seem to recall that the stagnation temperature for air at the leading edge of a reentry vehicle was inversely proportional to the radius of that edge. That's why the Shuttle has a nice round nosecone: they don't dare look like the Concorde or a fighter jet, because the tips of those nice sharp noses would simply melt off.
This is one of the reasons why, despite the Earth being continually pelted by thousands of tons a day of asteroidal material, it's rare that anything makes it to the ground: the small stuff just vaporizes first.
Obviously the temperature can't go to infinity, so there has to be some reason (continuum hypothesis failing at small enough distances?) why it doesn't... but even for centimeter radii leading edges we've only recently discovered ceramics that we think can survive the resulting reentry temperatures. What would let bacterial micrometer radii survive?
I think your #1 is off, too. At the very least, a bacterium reaching the Earth from another planet would have to be moving at Earth's escape velocity (because that's the velocity Earth's gravity would impart to it as it approaches), and that is 40% faster than the Shuttle's reentry velocity.
Is it too late to make this load of bacteria a little more intelligent?
It wasn't Lt. Calley who said that, BTW. I see your .sig on Slashdot frequently and the inaccuracy bugs me.
... never mind that.
It was said by an Army officer in a famous TV interview, back in the days when villages were being rebuilt into strongpoints that supposedly would then defend themselves against Viet Cong infiltrators. This theory ignored the fact that the villagers mostly despised the current economic system and their obscenely corrupt government, and therefore welcomed the VC as prophets of change, but
The point of the statement was that the old village had to be destroyed and replaced with a new, fortified, Army-built strongpoint in order to save it from the VC. The officer (a Captain IIRC) didn't see the irony of the situation which his statement so succinctly summarized.
I don't remember Calley saying anything particularly memorable. "I was just following orders" was already a trite, worn-out phrase by then.
What, you people think life is impossible on Jupiter? We don't know enough to say one way or the other. Who's to say Galileo's bacteria won't have some drastic effect on some Jovian life we are currently unaware of? Why contaminate Jupiter to save Europa from contamination? Why not just fling Galileo into the depths of space or into the sun if we want to get rid of it?
This smells to me of either not having been carefully thought through, or of unthinking assumptions that life must be impossible on Jupiter, when we simply don't know.
-Kasreyn
Kasreyn: Cheerfully playing the part of Devil's Advocate to hairtrigger