title: Did Mars once have martians?
authors.affiliation: Space Sciences Division at NASA's Ames Research Center, Moffett Field, California, USA.
authors.forename: C P
authors.initials: CP
authors.lastname: McKay
mesh_terms: D000864:Antarctic Regions; D001272:Atmosphere; D002245:Carbon Dioxide / Q000032:analysis; D002980:Climate; D017753:Ecosystem; D019419:Evolution, Planetary; D018559:Exobiology; D005118:Extraterrestrial Environment; D005580:Fossils; D017752:Greenhouse Effect; D018535:Mars; D018531:Spacecraft; D014867:Water
chemical_list: D014867:Water; D002245:Carbon Dioxide