-----Original Message-----
From: Gail & Roberta <[EMAIL PROTECTED]>
To: [EMAIL PROTECTED] <[EMAIL PROTECTED]>
Date: Monday, February 19, 2001 8:49 PM
Subject: OK, OK, OK, Enough!
Haven't we milked this one dry already? What does all this have to do with
the possible exploration of one of Jupiter's moons anyhow? So Fox came up
with a stupid, but apparently entertaining show that no one in their right
minds would believe? Isn't sci-fi by it's very nature the same thing? OK,
forget I said that. I love sci-fi, I love to watch reruns of Star Trek in
all its permutations, even Babylon 5 is entertaining. But science? Naw, and
I don't even pretend it is.
So let's get back to discussing Europa.
When we land there, will we need flotation devices to float on the possibly
slushy ice? If we land on an ice island and want to drill through, will the
island drift so much that we'll lose our probes? Is there an atmosphere? How
hot is the core? Lots more interesting stuff to speculate about than some
crap served up on TV, don't you think?
The trouble is that this group has already long since chewed all that over
extremely thoroughly, throughout 1999 and 2000 (apparently before you got
here) -- and we're simply running out of specifically Europa-related stuff
to discuss. (Hopefully there will soon be some more of it, as I recently
noted.) That's precisely why many of us have moved over to Jason Perry's
"ISSDG" and "Jupiter List" chat groups, which deal with Solar System
exploration in general.
Regarding your questions: Europa's crust is solid ice and anywhere from
several to several dozen km thick -- so we certainly don't need to worry
about floating on the surface or drifting on ice floes. It has an extremely
faint trace of atmosphere -- only a few hundred-millionths as dense as
Earth's -- and we have a good idea of most of the gases making it up. The
core may or may not be hot enough to provide any volcanic vents at all on
the floor of the subsurface ocean, but most of that floor is certainly near
0 deg C, just like most of Earth's ocean floor. (Europa's tidal heating
from Jupiter is only about 1/10 of Io's.) This still leaves a tremendous
number of interesting questions about the place, of course -- with one of
the most lively recent subjects being an increased feeling among scientists
that Jupiter's radiation may produce a disproportionate concentration of
nutrients and other biologically useful chemicals in the TOP few meters of
Europa's ice, and that these may both be slowly transported down into the
underground ocean, or nourish microbes in local pockets of near-surface
water within the ice. (This, in turn, would mean that a productive search
for Europan life may not have to dig nearly as far down into the ice as the
originaly Cryobot would have -- but then, there was some feeling along those
lines anyway, since it's always seemed likely that long-dead but extremely
well-preserved Europan microbes may be preserved in the ice even near its
top.)
Bruce Moomaw
==
You are subscribed to the Europa Icepick mailing list: [EMAIL PROTECTED]
Project information and list (un)subscribe info: http://klx.com/europa/
