Free Astronomy Magazine May-June 2018

PLANETOLOGY A bove, right and below, the location of the Filolao Crater on the north-western rim of the Moon. [NASA] the Philolaus Crater (70 km in diameter), only 550 km away from the lunar north pole. Identified in images recorded by the Lunar Reconnaissance Orbiter, the new skylights Astrobiological Exercise for Astronauts), through which potential future explorers of lunar and martian lava tubes gain experience with homol- ogous terrestrial structures and with other geological formations. A further reason for interest in lava tubes is the discovery, announced last January by the SETI Institute and the Mars In- stitute at NASA’s Lunar Science for Landed Missions Workshop, of three small cavities in