title: New perspectives on ancient Mars.
abstract: Mars was most active during its first billion years. The core, mantle, and crust formed within approximately 50 million years of solar system formation. A magnetic dynamo in a convecting fluid core magnetized the crust, and the global field shielded a more massive early atmosphere against solar wind stripping. The Tharsis province became a focus for volcanism, deformation, and outgassing of water and carbon dioxide in quantities possibly sufficient to induce episodes of climate warming. Surficial and near-surface water contributed to regionally extensive erosion, sediment transport, and chemical alteration. Deep hydrothermal circulation accelerated crustal cooling, preserved variations in crustal thickness, and modified patterns of crustal magnetization.
authors.affiliation: Department of Terrestrial Magnetism, Carnegie Institution of Washington, Washington, DC 20015, USA. scs@dtm.ciw.edu
authors.forename: Sean C
authors.initials: SC
authors.lastname: Solomon
authors.forename: Oded
authors.initials: O
authors.lastname: Aharonson
authors.forename: Jonathan M
authors.initials: JM
authors.lastname: Aurnou
authors.forename: W Bruce
authors.initials: WB
authors.lastname: Banerdt
authors.forename: Michael H
authors.initials: MH
authors.lastname: Carr
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Dombard
authors.forename: Herbert V
authors.initials: HV
authors.lastname: Frey
authors.forename: Matthew P
authors.initials: MP
authors.lastname: Golombek
authors.forename: Steven A
authors.initials: SA
authors.lastname: Hauck
authors.forename: James W
authors.initials: JW
authors.lastname: Head
authors.forename: Bruce M
authors.initials: BM
authors.lastname: Jakosky
authors.forename: Catherine L
authors.initials: CL
authors.lastname: Johnson
authors.forename: Patrick J
authors.initials: PJ
authors.lastname: McGovern
authors.forename: Gregory A
authors.initials: GA
authors.lastname: Neumann
authors.forename: Roger J
authors.initials: RJ
authors.lastname: Phillips
authors.forename: David E
authors.initials: DE
authors.lastname: Smith
authors.forename: Maria T
authors.initials: MT
authors.lastname: Zuber
mesh_terms: D001272:Atmosphere; D002980:Climate; D005118:Extraterrestrial Environment; D008280:Magnetics; D018535:Mars; D013696:Temperature; D014867:Water
chemical_list: D014867:Water