Ron Baalke wrote:
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RELEASE: 03-297

GALILEO TO TASTE JUPITER BEFORE TAKING FINAL PLUNGE

In the end, the Galileo spacecraft will get a taste of
Jupiter before taking a final plunge into the planet's
crushing atmosphere, ending the mission on Sunday, Sept. 21.
....
The spacecraft has been purposely put on a collision course
with Jupiter to eliminate any chance of an unwanted impact
between the spacecraft and Jupiter's moon Europa, which
Galileo discovered is likely to have a subsurface ocean.

At some heights in the Jupiter atmosphere the physical
conditions might be suitable to sustain life.
Since temperature increases inward, at some level it must
traverse the 0-100 C interval in layers where water and organic
molecules must be present, and well shielded from cosmic rays.

Apparently NASA seems to be sure enough that either no life
can exist within Jupiter, or that Galileo will be completely
sterilized before entering such "comfortable" atmospheric layers.

Dan