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Melting Europa
amigoro writes "After having contaminated Earth's Oceans, it seems that there are plans to send a probe drilling through Europa's ice sheet and explore the purported ocean below the crust. The plan seems to be to find Life there. But I wonder how long the time lag will be between the probe finding life, and a leak in the radioactive heater wiping all of it out."
Apparently some recent research has indicated that the ice on Europa may be quite a bit thicker than initially thought. I'd post a link if I had one (but I don't) The thickness of the ice sheet may well be such that getting to the ocean below (assuming there is one) could turn out to be impractical, even using heat.
Roving Web-Teleoperated Robot
Isn't Europa in Jupiter's radiation belts? In otherwords, a tiny amount of radiation released from a probe would probably be nothing compared to what the "ocean" experiences everyday? (I could be way off base, though)
Doh!
http://www.nas.nasa.gov/Main/Features/2000/Fall/sp ace_pic1.html
Europa is already highly radioactive. It's around 19 Mrads thanks to this thing we call Jupiter. Saying that a radioactive probe could potentialy destroy any life already there is akin to saying that my bottle of water could kill off life in the pacific. Its people like the poster of this story that the website about "dihydrogen monoxide" is meant to catch.
we have little knowledge of its atmospheric conditions
Actually, we have very good knowledge of Europa's atmospheric conditions, i.e. it doesn't have one (well, no more so than our own moon). On a side note, the vast majority of failed Mars missions were lost not because of the difficulties of navigating the atmosphere but because of things like a rocket motor blowing up, or an incorrect course adjustment, these problems occuring well before any martian atmosphere was encountered.
Estimates for the thickness of the ice on Europa vary, but think kilometers, not meters, except for a few areas, like the so-called Conemara cliffs region, were it could be much thiner, possibly due to a local hot spot.
"Just once, I'd like to meet an alien menace that wasn't immune to bullets." -- The Brigadier, Dr. Who
Look: The Galileo probe had contamination problems because it was designed for a space-only mission, and therefore was not subjected to a rigorous decontamination process before launch.
Therefore, when the possibility arose that it might crash on Europa, the decision was made to burn the probe rather than risk contamination.
Since this probe is intended to actually land on Europa, it will be subjected to the rigorous decontaminiation process that is already in place and applied as part of the standard prep checklst for planetary missions (such as the Mars rovers, for example).
Summary:
Galileo--space mission, not decontaminated, not allowed to land on Europa.
Europa Probe--planetary mission, decontaminated, intended to land on Europa.
You--not smarter than NASA.
Any sufficiently well-organized community is indistinguishable from Government.
Actually the investigation on the crash of the Beagle II was pointing towards a difference in the expected density of the Martian atmosphere casuing the landing mechanism to fail (i.e. it came in too fast). A lot of the probes have to "brake" by skidding through the upper layers of the atmosphere, which can be rather risky but necessary sometimes for the corret orbital positioning.
Martian atmospheric conditions are rather important for landing probes.
And to the previous poster, well it turns out that Europa has an atmosphere. Galileo returned data on the ionosphere and atmospheric conditions on Europa, that is why further study is needed on such atmosphere as the original poster in this thread sugested.