The search for life beyond Earth got more exciting today.
That’s because University of Texas scientists have identified that not only do large oceans of water exist beneath the surface of Europa, but that there’s likely vigorous interaction between that water and the icy surface.
Scientists have long debated the thickness of the ice on the surface of Europa, which is slightly smaller than Earth’s moon and orbits Jupiter. One of the tantalyzing clues, regarding thickness and what lurks beneath, has been the chaotic terrain on the surface of the moon, known as Conamara Chaos.
How could these bumpy, icy blocks exist?
Generally scientists believe that a thick sheet of ice would be bad for life because it would inhibit the transfer of energy and nutrients from the moon’s surface and the ocean beneath it.
But now Texas scientists, studying archival data from the Galileo spacecraft and comparing it to similar processes on Earth, such as ice shelves, developed a model to explain how the chaotic terrain could form on Europa.
The work, led by a UT postdoc, Britney Schmidt, is published in Nature today.
From their model they have inferred that large lakes must exist just a few miles beneath the surface of Europa. As part if their model the scientists say surface ice shelves must be collapsing into the sub-surface lakes.
Of course we won’t know for sure that this theory is correct until we smash a probe into the surface of the moon, to study the shell and oceans beneath. And who knows, the probe might even discover life.
Such a mission has been proposed, and was rated as the second-highest priority flagship mission by the National Research Council’s recent Planetary Science Decadal Survey (see report, large .pdf file).
But a Europa explorer would be very expensive, however, on the order of $4.7 billion according to the decadal survey. So I wouldn’t expect to see it any time soon given the current fiscal environment.
Which leaves us with studying ice sheet processes on Earth, life in extreme environments, and wondering what might be out there.
It beats celebrity watching.