Meteorites at Meridiani Planum provide evidence for significant amounts of surface and near-surface water on early Mars

摘要: Abstract– Six large iron meteorites have been discovered in the Meridiani Planum region of Mars by Exploration Rover Opportunity a nearly 25 km-long traverse. Herein, we review and synthesize available data to propose that discovery characteristics six could be explained as result their impact into soft wet surface, sometime during Noachian or Hesperian, subsequently exposed at Martian surface through differential erosion. As recorded its sediments chemical deposits, has interpreted undergone watery past, including shallow sea, playa, an environment fluctuating ground water, and/or icy landscape. Meteorites encased upon buried, kept underground for long time, shielded from atmosphere. The apparently underwent significant weathering due aqueous alteration, indicated cavernous features suggest acidic corrosion removing less resistant material softer inclusions. During Amazonian, almost complete disappearance water desiccation landscape, followed induration subsequent erosion degradation sediments, least 10–80 m deflation last 3–3.5 Gy, would buried meteorites. We conclude support hypothesis once had denser atmosphere considerable amounts ice near surface.