Looking For Life On Europa

Many scientists think life might exist on Jupiter's ice-covered moon, Europa. They think Europa has an ocean rich in oxygen under the ice-- an ocean that could be one hundred miles deep. To look for life in that ocean, NASA and others are studying landing a probe on the surface and somehow drilling through the ice, or possibly melting the ice, to reach the ocean below.

There might be a cheaper, faster way, however. Richard Greenberg, of the University of Arizona's Lunar and Planetary Institute, argues rovers should be sent. He points out there are few craters on Europa, which likely means the surface is regularly refreshed with water and ice coming up from below. Running a rover across newly created surface, therefore, could possibly allow us to come upon evidence of life below that was thrown to the surface with the water. That evidence could be as dramatic as the body of an unfortunate creature deposited on the surface to die in the powerful radiation that pounds the icy shell.

Of course, a rover mission would depend to some large degree on sheer luck to find evidence of life, but it could be done relatively cheaply, sooner than a larger, more complex effort aimed at actually reaching the ocean below, and could return valuable science even if it didn't bag proof of life beyond Earth.