Adrian Brown – a planetary scientist at the SETI Institute who analyses spectroscopic data gathered by the Mars Reconnaissance Orbiter. For example, he’s interested in finding subtle hints that large bodies of water might once have flooded the northern regions of this now-dry world, hints that the Orbiter’s spectroscope could provide. In addition to his search for water, he also hunts for clues to volcanic activity in these same northern realms, because the energy provided by such eruptions could fuel microscopic life. A native of Australia, Adrian has spent a lot of time walking the rugged outback of the western part of that continent, learning how minerals in dry environments can be the fingerprints of water. That expertise helps him search for clues to Mars’ hydraulic past, when not just water, but alien life might have decked the landscape.