Details

Autor(en) / Beteiligte

• Piqueux, Sylvain
• Buz, Jennifer
• Edwards, Christopher S.
• Bandfield, Joshua L.
• Kleinböhl, Armin
• Kass, David M.
• Hayne, Paul O.

Titel

Widespread Shallow Water Ice on Mars at High Latitudesand Midlatitudes

Ist Teil von

• Geophysical research letters, 2019-12, Vol.46 (24), p.14290-14298

Ort / Verlag

Washington: John Wiley & Sons, Inc

Erscheinungsjahr

2019

Quelle

Wiley Online Library Journals【Remote access available】

Beschreibungen/Notizen

• We derive the depth of the water ice table on Mars by fitting seasonal surface temperature trends acquired by the Mars Climate Sounder and Thermal Emission Imaging System with a two‐layer regolith model assuming frozen H2O as the lower material. Our results are consistent with widespread water ice at latitudes as low as 35°N/45°S buried sometimes a few centimeters below sand‐like material, with high lateral ice depth variability, and correlated with periglacial features. While several investigations have already predicted, identified, and characterized some properties of near‐surface ice on Mars, our results constitute a significant advance in the context of the upcoming crewed exploration because (1) they focus on very shallow depths accessible with limited equipment, (2) they provide continuous regional coverage including the midlatitudes, and (3) they yield moderate spatial resolution maps (3 ppd) relevant to landing site selection studies. Plain Language Summary Frozen water is a very strong heat conductor compared to typical Martian regolith. As a result, near‐surface ice measurably influences seasonal surface temperature trends, and the depth of the H2O table controls the amplitude of this effect. We leverage this influence on orbital temperature observations using a numerical heat transfer model to derive regional and local maps of the ice depth on Mars, at much higher spatial resolution than previously available. We show that water ice is present sometimes just a few centimeters below the surface, at locations where future landing is realistic, under mobile material that could easily be moved around. This ice could be exploited on‐site for drinking water, breathable oxygen, etc., at a much lower cost than if brought from Earth. Key Points Shallow subsurface water ice on Mars influences seasonal surface temperatures in a measurable manner with MCS and THEMIS We leverage this effect to map the depth to the water ice table at middle and high latitudes Large continuous units of shallow ice are found ~35°N and ~45°S and could be exploited for future crewed missions