Impact Excavation and the Search for Subsurface Life on Mars

doi:10.1006/icar.2001.6725

Icarus

Volume 155, Issue 2, February 2002, Pages 340-349

https://doi.org/10.1006/icar.2001.6725 Get rights and content

Abstract

Because of the ubiquity of subsurface microbial life on Earth, examination of the subsurface of Mars could provide an answer to the question of whether microorganisms exist or ever existed on that planet. Impact craters provide a natural mechanism for accessing the deep substrate of Mars and exploring its exobiological potential. Based on equations that relate impact crater diameters to excavation depth we estimate the observed crater diameters that are required to prospect to given depths in the martian subsurface and we relate these depths to observed microbiological phenomena in the terrestrial subsurface. Simple craters can be used to examine material to a depth of ∼270 m. Complex craters can be used to reach greater depths, with craters of diameters ≥300 km required to reach depths of 6 km or greater, which represent the limit of the terrestrial deep subsurface biosphere. Examination of the ejecta blankets of craters between 17.5 and 260 km in diameter would provide insights into whether there is an extant, or whether there is evidence of an extinct, deep subsurface microbiota between 500 and 5000 m prior to committing to large-scale drilling efforts. At depths <500 m some crater excavations are likely to be more important than others from an exobiological point of view. We discuss examples of impacts into putative intracrater paleolacustrine sediments and regions associated with hydrothermal activity. We compare these depths to the characteristics of subsurface life on Earth and the fossil microbiological record in terrestrial impact craters.

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Regular ArticleImpact Excavation and the Search for Subsurface Life on Mars

Abstract

Icarus

Icarus

Icarus

Icarus

FEMS Microbiol. Rev.

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Planetary Space Sci.

FEMS Microbiol. Lett.

Planet. Space Sci.

Systemat. Appl. Microbiol.

Palaeogeog. Palaeoclim. Palaeoecol.

FEMS Microbiol. Rev.

FEMS Microbiol. Lett.

FEMS Microbiol. Rev.

Exobiology at Sinus Meridiani—2003 and beyond

First Landing Site Workshop for the 2003 Mars Exploration Rovers

The Channels of Mars

Ancient oceans, ice sheets and the hydrologic cycle on Mars

Nature

Potential MER landing sites in the Terra Meridiani and Valles Marineris regions of Mars

First Landing Site Workshop for the 2003 Mars Exploration Rovers

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Lunar Planet. Sci.

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J. Geophys. Res.

Variations in the onset diameter for martian layered ejecta morphologies and their implications for subsurface volatile reservoirs

Geophys. Res. Lett.

The search for organic substances and inorganic volatile compounds in the surface of Mars

J. Geophys. Res.

Assessing layered materials in Gale crater

First Landing Site Workshop for the 2003 Mars Exploration Rovers

Exploring impact crater paleolakes in 2003

First Landing Site Workshop for the 2003 Mars Exploration Rovers

Water on Mars

Status of the European Mars Express mission

Lunar Planet. Sci.

Detection of crystalline hematite mineralization on Mars by the thermal emission spectrometer: Evidence for near-surface water

J. Geophys. Res.

The distribution of crystalline hematite on Mars from the thermal emission spectrometer: Evidence for liquid water

Lunar Planet. Sci.

The TES Hematite-rich region in Sinus Meridiani: A proposed landing site for the 2003 rover

First Landing Site Workshop for the 2003 Mars Exploration Rovers

A model for the hydrologic and climatic behavior of water on Mars

J. Geophys. Res.

Microbial mats in the Tswaing impact crater, South Africa—Results from a South African exobiology expedition and implications for the search for biological molecules on Mars

Lunar Planet. Sci.

The scaling of complex craters

J. Geophys. Res.

Detection of viable yeast in 3-million-year-old permafrost soils of Siberia

Microbiology

Bacterial mats from Crater-lake, Oregon, USA and their relationship to possible deep-lake hydrothermal venting

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J. Geophys. Res. Lett.

Geometric properties of martian impact craters: Preliminary results from the Mars orbiter laser altimeter

Geophys. Res. Lett.

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Oil Gas J.

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Regular Article
Impact Excavation and the Search for Subsurface Life on Mars