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Rummel JD, Beaty DW, Jones MA, Bakermans C, Barlow NG, Boston PJ, Chevrier VF, Clark BC, de Vera JPP, Gough RV, Hallsworth JE, Head JW, Hipkin VJ, Kieft TL, McEwen AS, Mellon MT, Mikucki JA, Nicholson WL, Omelon CR, Peterson R, Roden EE, Sherwood Lollar B, Tanaka KL, Viola D, Wray JJ. A new analysis of Mars "Special Regions": findings of the second MEPAG Special Regions Science Analysis Group (SR-SAG2). ASTROBIOLOGY 2014; 14:887-968. [PMID: 25401393 DOI: 10.1089/ast.2014.1227] [Citation(s) in RCA: 148] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
A committee of the Mars Exploration Program Analysis Group (MEPAG) has reviewed and updated the description of Special Regions on Mars as places where terrestrial organisms might replicate (per the COSPAR Planetary Protection Policy). This review and update was conducted by an international team (SR-SAG2) drawn from both the biological science and Mars exploration communities, focused on understanding when and where Special Regions could occur. The study applied recently available data about martian environments and about terrestrial organisms, building on a previous analysis of Mars Special Regions (2006) undertaken by a similar team. Since then, a new body of highly relevant information has been generated from the Mars Reconnaissance Orbiter (launched in 2005) and Phoenix (2007) and data from Mars Express and the twin Mars Exploration Rovers (all 2003). Results have also been gleaned from the Mars Science Laboratory (launched in 2011). In addition to Mars data, there is a considerable body of new data regarding the known environmental limits to life on Earth-including the potential for terrestrial microbial life to survive and replicate under martian environmental conditions. The SR-SAG2 analysis has included an examination of new Mars models relevant to natural environmental variation in water activity and temperature; a review and reconsideration of the current parameters used to define Special Regions; and updated maps and descriptions of the martian environments recommended for treatment as "Uncertain" or "Special" as natural features or those potentially formed by the influence of future landed spacecraft. Significant changes in our knowledge of the capabilities of terrestrial organisms and the existence of possibly habitable martian environments have led to a new appreciation of where Mars Special Regions may be identified and protected. The SR-SAG also considered the impact of Special Regions on potential future human missions to Mars, both as locations of potential resources and as places that should not be inadvertently contaminated by human activity.
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Affiliation(s)
- John D Rummel
- 1 Department of Biology, East Carolina University , Greenville, North Carolina, USA
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Martínez GM, Rennó N, Fischer E, Borlina CS, Hallet B, de la Torre Juárez M, Vasavada AR, Ramos M, Hamilton V, Gomez-Elvira J, Haberle RM. Surface energy budget and thermal inertia at Gale Crater: Calculations from ground-based measurements. JOURNAL OF GEOPHYSICAL RESEARCH. PLANETS 2014; 119:1822-1838. [PMID: 26213666 PMCID: PMC4508907 DOI: 10.1002/2014je004618] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2014] [Accepted: 07/12/2014] [Indexed: 05/28/2023]
Abstract
The analysis of the surface energy budget (SEB) yields insights into soil-atmosphere interactions and local climates, while the analysis of the thermal inertia (I) of shallow subsurfaces provides context for evaluating geological features. Mars orbital data have been used to determine thermal inertias at horizontal scales of ∼104 m2 to ∼107 m2. Here we use measurements of ground temperature and atmospheric variables by Curiosity to calculate thermal inertias at Gale Crater at horizontal scales of ∼102 m2. We analyze three sols representing distinct environmental conditions and soil properties, sol 82 at Rocknest (RCK), sol 112 at Point Lake (PL), and sol 139 at Yellowknife Bay (YKB). Our results indicate that the largest thermal inertia I = 452 J m-2 K-1 s-1/2 (SI units used throughout this article) is found at YKB followed by PL with I = 306 and RCK with I = 295. These values are consistent with the expected thermal inertias for the types of terrain imaged by Mastcam and with previous satellite estimations at Gale Crater. We also calculate the SEB using data from measurements by Curiosity's Rover Environmental Monitoring Station and dust opacity values derived from measurements by Mastcam. The knowledge of the SEB and thermal inertia has the potential to enhance our understanding of the climate, the geology, and the habitability of Mars.
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Affiliation(s)
- G M Martínez
- Department of Atmospheric, Oceanic and Space Sciences, University of MichiganAnn Arbor, Michigan, USA
| | - N Rennó
- Department of Atmospheric, Oceanic and Space Sciences, University of MichiganAnn Arbor, Michigan, USA
| | - E Fischer
- Department of Atmospheric, Oceanic and Space Sciences, University of MichiganAnn Arbor, Michigan, USA
| | - C S Borlina
- Department of Atmospheric, Oceanic and Space Sciences, University of MichiganAnn Arbor, Michigan, USA
| | - B Hallet
- Department of Earth and Space Sciences, University of WashingtonSeattle, Washington, USA
| | | | - A R Vasavada
- Jet Propulsion LaboratoryPasadena, California, USA
| | - M Ramos
- Departamento de Física, Universidad de Alcalá de HenaresMadrid, Spain
| | - V Hamilton
- Department of Space Studies, Southwest Research InstituteBoulder, Colorado, USA
| | | | - R M Haberle
- Space Science Division, NASA Ames Research CenterMoffett Field, California, USA
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Searls ML, Mellon MT, Cull S, Hansen CJ, Sizemore HG. Seasonal defrosting of the Phoenix landing site. ACTA ACUST UNITED AC 2010. [DOI: 10.1029/2009je003438] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Sizemore HG, Mellon MT, Searls ML, Lemmon MT, Zent AP, Heet TL, Arvidson RE, Blaney DL, Keller HU. In situ analysis of ice table depth variations in the vicinity of small rocks at the Phoenix landing site. ACTA ACUST UNITED AC 2010. [DOI: 10.1029/2009je003414] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Mellon MT, Arvidson RE, Sizemore HG, Searls ML, Blaney DL, Cull S, Hecht MH, Heet TL, Keller HU, Lemmon MT, Markiewicz WJ, Ming DW, Morris RV, Pike WT, Zent AP. Ground ice at the Phoenix Landing Site: Stability state and origin. ACTA ACUST UNITED AC 2009. [DOI: 10.1029/2009je003417] [Citation(s) in RCA: 140] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Arvidson RE, Bonitz RG, Robinson ML, Carsten JL, Volpe RA, Trebi-Ollennu A, Mellon MT, Chu PC, Davis KR, Wilson JJ, Shaw AS, Greenberger RN, Siebach KL, Stein TC, Cull SC, Goetz W, Morris RV, Ming DW, Keller HU, Lemmon MT, Sizemore HG, Mehta M. Results from the Mars Phoenix Lander Robotic Arm experiment. ACTA ACUST UNITED AC 2009. [DOI: 10.1029/2009je003408] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Smith PH, Tamppari LK, Arvidson RE, Bass D, Blaney D, Boynton WV, Carswell A, Catling DC, Clark BC, Duck T, Dejong E, Fisher D, Goetz W, Gunnlaugsson HP, Hecht MH, Hipkin V, Hoffman J, Hviid SF, Keller HU, Kounaves SP, Lange CF, Lemmon MT, Madsen MB, Markiewicz WJ, Marshall J, McKay CP, Mellon MT, Ming DW, Morris RV, Pike WT, Renno N, Staufer U, Stoker C, Taylor P, Whiteway JA, Zent AP. H2O at the Phoenix landing site. Science 2009; 325:58-61. [PMID: 19574383 DOI: 10.1126/science.1172339] [Citation(s) in RCA: 102] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
The Phoenix mission investigated patterned ground and weather in the northern arctic region of Mars for 5 months starting 25 May 2008 (solar longitude between 76.5 degrees and 148 degrees ). A shallow ice table was uncovered by the robotic arm in the center and edge of a nearby polygon at depths of 5 to 18 centimeters. In late summer, snowfall and frost blanketed the surface at night; H(2)O ice and vapor constantly interacted with the soil. The soil was alkaline (pH = 7.7) and contained CaCO(3), aqueous minerals, and salts up to several weight percent in the indurated surface soil. Their formation likely required the presence of water.
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Affiliation(s)
- P H Smith
- Lunar and Planetary Laboratory, University of Arizona, Tucson, AZ 85721, USA.
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Hudson TL, Aharonson O, Schorghofer N. Laboratory experiments and models of diffusive emplacement of ground ice on Mars. ACTA ACUST UNITED AC 2009. [DOI: 10.1029/2008je003149] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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