David Rothery investigates volcanism on Earth and elsewhere in the Solar System using remote-sensing Earth-orbiting satellites and space probes.  Mercury is his present focus, and he is lead co-investigator for geology on the X-ray spectrometer aboard BepiColombo, an ESA mission currently on its way to Mercury.  He describes some intriguing puzzles about Mercury that he hopes BepiColombo will resolve, as well as a type of volcanism occurring on some icy bodies in the outer solar system called cryovolcanism.
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