title: The gravity field of Mars: results from Mars Global Surveyor.
abstract: Observations of the gravity field of Mars reveal a planet that has responded differently in its northern and southern hemispheres to major impacts and volcanic processes. The rough, elevated southern hemisphere has a relatively featureless gravitational signature indicating a state of near-isostatic compensation, whereas the smooth, low northern plains display a wider range of gravitational anomalies that indicates a thinner but stronger surface layer than in the south. The northern hemisphere shows evidence for buried impact basins, although none large enough to explain the hemispheric elevation difference. The gravitational potential signature of Tharsis is approximately axisymmetric and contains the Tharsis Montes but not the Olympus Mons or Alba Patera volcanoes. The gravity signature of Valles Marineris extends into Chryse and provides an estimate of material removed by early fluvial activity.
authors.affiliation: Laboratory for Terrestrial Physics, National Aeronautics and Space Administration (NASA) Goddard Space Flight Center, Greenbelt, MD 20771, USA. dsmith@tharsis.gsfc.nasa.gov
authors.forename: D E
authors.initials: DE
authors.lastname: Smith
authors.forename: W L
authors.initials: WL
authors.lastname: Sjogren
authors.forename: G L
authors.initials: GL
authors.lastname: Tyler
authors.forename: G
authors.initials: G
authors.lastname: Balmino
authors.forename: F G
authors.initials: FG
authors.lastname: Lemoine
authors.forename: A S
authors.initials: AS
authors.lastname: Konopliv
mesh_terms: D001272:Atmosphere; D005118:Extraterrestrial Environment; D018471:Hypergravity; D007053:Ice; D018535:Mars
chemical_list: D007053:Ice