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Mitrofanov IG, Nikiforov SY, Djachkova MV, Lisov DI, Litvak ML, Sanin AB, Vasavada AR. Water and Chlorine in the Martian Subsurface Along the Traverse of NASA's Curiosity Rover: 1. DAN Measurement Profiles Along the Traverse. J Geophys Res Planets 2022; 127:e2022JE007327. [PMID: 36588803 PMCID: PMC9788246 DOI: 10.1029/2022je007327] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/06/2022] [Revised: 10/28/2022] [Accepted: 11/06/2022] [Indexed: 06/17/2023]
Abstract
This paper presents estimates of the water and chlorine contents in the subsurface of Gale crater based on the measurements by the Dynamic Albedo of Neutrons (DAN) instrument onboard the NASA Curiosity rover. It is Part 1 of a two-paper series. Data derived both from DAN active and passive measurements are presented in discrete surface areas (pixels) assuming a homogeneous distribution of water within the DAN sensing depth (60 cm) along the traverse of the rover. It is shown that the content of hydrogen, reported as Water Equivalent Hydrogen, varies between almost zero and a maximum of (6.1 ± 0.7) wt.%. The content of absorption equivalent chlorine varies between almost zero and (2.6 ± 0.2) wt.%. Such variations are thought to be related to the different geological processes and environmental conditions present in the strata along the traverse during the evolutionary history of Gale crater. The second paper (Part 2) studies particular properties of water and abundances of neutron absorbing elements at distinct geological regions, that the rover crossed on its way.
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Affiliation(s)
- I. G. Mitrofanov
- Space Research Institute of the Russian Academy of Sciences (IKI)MoscowRussia
| | - S. Y. Nikiforov
- Space Research Institute of the Russian Academy of Sciences (IKI)MoscowRussia
| | - M. V. Djachkova
- Space Research Institute of the Russian Academy of Sciences (IKI)MoscowRussia
| | - D. I. Lisov
- Space Research Institute of the Russian Academy of Sciences (IKI)MoscowRussia
| | - M. L. Litvak
- Space Research Institute of the Russian Academy of Sciences (IKI)MoscowRussia
| | - A. B. Sanin
- Space Research Institute of the Russian Academy of Sciences (IKI)MoscowRussia
| | - A. R. Vasavada
- Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaCAUSA
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Litvak ML, Mitrofanov IG, Sanin AB, Bakhtin B, Golovin DV, Zeitlin C. Observations of neutron radiation environment during Odyssey cruise to Mars. Life Sci Space Res (Amst) 2021; 29:53-62. [PMID: 33888288 DOI: 10.1016/j.lssr.2021.03.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2020] [Revised: 03/10/2021] [Accepted: 03/15/2021] [Indexed: 06/12/2023]
Abstract
In April 2001, Mars Odyssey spacecraft with the High Energy Neutron Detector (HEND) onboard was launched to Mars. HEND/Odyssey was switched on measurement mode for most of transit to Mars to monitor variations of spacecraft background and solar activity. Although HEND/Odyssey was originally designed to measure Martian neutron albedo and to search for Martian subsurface water/water ice, its measurements during cruise phase to Mars are applicable to evaluate spacecraft ambient radiation background. The biological impact of the neutron component of this radiation background should be understood, as it must be taken into account in planning future human missions to Mars. We have modeled the spacecraft neutron spectral density and compared it with HEND measurements to estimate neutron dose equivalent rates during Odyssey cruise phase, which occurred during the maximum period of solar cycle 23. We find that the Odyssey ambient neutron environment during May - September 2001 yields 10.6 ± 2.0 μSv per day in the energy range from 0 to 15 MeV, and about 29 μSv per day when extrapolated to the 0-1000 MeV energy range during solar quiet time (intervals without Solar Particle Events, SPEs). We have also extrapolated HEND/Odyssey measurements to different periods of solar cycle and find that during solar minimum (maximum of GCR flux), the neutron dose equivalent rate during cruise to Mars could be as high as 52 μSv per day with the same shielding. These values are in good agreement with results reported for a similar measurement made with an instrument aboard the Mars Science Laboratory during its cruise to Mars in 2011-2012.
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Affiliation(s)
- M L Litvak
- Space Research Institute, RAS, Moscow, 117997, Russia.
| | | | - A B Sanin
- Space Research Institute, RAS, Moscow, 117997, Russia
| | - B Bakhtin
- Space Research Institute, RAS, Moscow, 117997, Russia
| | - D V Golovin
- Space Research Institute, RAS, Moscow, 117997, Russia
| | - C Zeitlin
- Leidos, Inc., Houston, TX 77058, USA
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Ehlmann BL, Edgett KS, Sutter B, Achilles CN, Litvak ML, Lapotre MGA, Sullivan R, Fraeman AA, Arvidson RE, Blake DF, Bridges NT, Conrad PG, Cousin A, Downs RT, Gabriel TSJ, Gellert R, Hamilton VE, Hardgrove C, Johnson JR, Kuhn S, Mahaffy PR, Maurice S, McHenry M, Meslin PY, Ming DW, Minitti ME, Morookian JM, Morris RV, O'Connell-Cooper CD, Pinet PC, Rowland SK, Schröder S, Siebach KL, Stein NT, Thompson LM, Vaniman DT, Vasavada AR, Wellington DF, Wiens RC, Yen AS. Chemistry, mineralogy, and grain properties at Namib and High dunes, Bagnold dune field, Gale crater, Mars: A synthesis of Curiosity rover observations. J Geophys Res Planets 2017; 122:2510-2543. [PMID: 29497589 DOI: 10.1002/2016je005225] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2017] [Revised: 05/18/2017] [Accepted: 05/19/2017] [Indexed: 05/25/2023]
Abstract
The Mars Science Laboratory Curiosity rover performed coordinated measurements to examine the textures and compositions of aeolian sands in the active Bagnold dune field. The Bagnold sands are rounded to subrounded, very fine to medium sized (~45-500 μm) with ≥6 distinct grain colors. In contrast to sands examined by Curiosity in a dust-covered, inactive bedform called Rocknest and soils at other landing sites, Bagnold sands are darker, less red, better sorted, have fewer silt-sized or smaller grains, and show no evidence for cohesion. Nevertheless, Bagnold mineralogy and Rocknest mineralogy are similar with plagioclase, olivine, and pyroxenes in similar proportions comprising >90% of crystalline phases, along with a substantial amorphous component (35% ± 15%). Yet Bagnold and Rocknest bulk chemistry differ. Bagnold sands are Si enriched relative to other soils at Gale crater, and H2O, S, and Cl are lower relative to all previously measured Martian soils and most Gale crater rocks. Mg, Ni, Fe, and Mn are enriched in the coarse-sieved fraction of Bagnold sands, corroborated by visible/near-infrared spectra that suggest enrichment of olivine. Collectively, patterns in major element chemistry and volatile release data indicate two distinctive volatile reservoirs in Martian soils: (1) amorphous components in the sand-sized fraction (represented by Bagnold) that are Si-enriched, hydroxylated alteration products and/or H2O- or OH-bearing impact or volcanic glasses and (2) amorphous components in the fine fraction (<40 μm; represented by Rocknest and other bright soils) that are Fe, S, and Cl enriched with low Si and adsorbed and structural H2O.
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Ehlmann BL, Edgett KS, Sutter B, Achilles CN, Litvak ML, Lapotre MGA, Sullivan R, Fraeman AA, Arvidson RE, Blake DF, Bridges NT, Conrad PG, Cousin A, Downs RT, Gabriel TSJ, Gellert R, Hamilton VE, Hardgrove C, Johnson JR, Kuhn S, Mahaffy PR, Maurice S, McHenry M, Meslin P, Ming DW, Minitti ME, Morookian JM, Morris RV, O'Connell‐Cooper CD, Pinet PC, Rowland SK, Schröder S, Siebach KL, Stein NT, Thompson LM, Vaniman DT, Vasavada AR, Wellington DF, Wiens RC, Yen AS. Chemistry, mineralogy, and grain properties at Namib and High dunes, Bagnold dune field, Gale crater, Mars: A synthesis of Curiosity rover observations. J Geophys Res Planets 2017; 122:2510-2543. [PMID: 29497589 PMCID: PMC5815393 DOI: 10.1002/2017je005267] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2017] [Revised: 05/18/2017] [Accepted: 05/19/2017] [Indexed: 05/31/2023]
Abstract
The Mars Science Laboratory Curiosity rover performed coordinated measurements to examine the textures and compositions of aeolian sands in the active Bagnold dune field. The Bagnold sands are rounded to subrounded, very fine to medium sized (~45-500 μm) with ≥6 distinct grain colors. In contrast to sands examined by Curiosity in a dust-covered, inactive bedform called Rocknest and soils at other landing sites, Bagnold sands are darker, less red, better sorted, have fewer silt-sized or smaller grains, and show no evidence for cohesion. Nevertheless, Bagnold mineralogy and Rocknest mineralogy are similar with plagioclase, olivine, and pyroxenes in similar proportions comprising >90% of crystalline phases, along with a substantial amorphous component (35% ± 15%). Yet Bagnold and Rocknest bulk chemistry differ. Bagnold sands are Si enriched relative to other soils at Gale crater, and H2O, S, and Cl are lower relative to all previously measured Martian soils and most Gale crater rocks. Mg, Ni, Fe, and Mn are enriched in the coarse-sieved fraction of Bagnold sands, corroborated by visible/near-infrared spectra that suggest enrichment of olivine. Collectively, patterns in major element chemistry and volatile release data indicate two distinctive volatile reservoirs in Martian soils: (1) amorphous components in the sand-sized fraction (represented by Bagnold) that are Si-enriched, hydroxylated alteration products and/or H2O- or OH-bearing impact or volcanic glasses and (2) amorphous components in the fine fraction (<40 μm; represented by Rocknest and other bright soils) that are Fe, S, and Cl enriched with low Si and adsorbed and structural H2O.
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Mitrofanov IG, Litvak ML, Nikiforov SY, Jun I, Bobrovnitsky YI, Golovin DV, Grebennikov AS, Fedosov FS, Kozyrev AS, Lisov DI, Malakhov AV, Mokrousov MI, Sanin AB, Shvetsov VN, Timoshenko GN, Tomilina TM, Tret'yakov VI, Vostrukhin AA. The ADRON-RM Instrument Onboard the ExoMars Rover. Astrobiology 2017; 17:585-594. [PMID: 28731818 DOI: 10.1089/ast.2016.1566] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
This overview presents the physical principles, design, measurement capabilities, and summary of planned operations of the autonomous detector of radiation of neutrons onboard rover at Mars (ADRON-RM) on the surface of Mars. ADRON-RM is a Russian project selected for the joint European Space Agency-Roscosmos ExoMars 2020 landing mission. A compact passive neutron spectrometer, ADRON-RM, was designed to study the abundance and distribution of water and neutron absorption elements (such as Cl, Fe, and others) in the martian subsurface along the path of the ExoMars rover. Key Words: Mars exploration-Surface-Neutron Spectroscopy-Water. Astrobiology 17, 585-594.
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Affiliation(s)
- I G Mitrofanov
- 1 Institute for Space Research , Russian Academy of Sciences, Moscow, Russia
| | - M L Litvak
- 1 Institute for Space Research , Russian Academy of Sciences, Moscow, Russia
| | - S Y Nikiforov
- 1 Institute for Space Research , Russian Academy of Sciences, Moscow, Russia
| | - I Jun
- 2 Jet Propulsion Laboratory, California Institute of Technology , Pasadena, California
| | - Y I Bobrovnitsky
- 3 A.A. Blagonravov Institute of Mechanical Engineering , Russian Academy of Sciences, Moscow, Russia
| | - D V Golovin
- 1 Institute for Space Research , Russian Academy of Sciences, Moscow, Russia
| | - A S Grebennikov
- 3 A.A. Blagonravov Institute of Mechanical Engineering , Russian Academy of Sciences, Moscow, Russia
| | - F S Fedosov
- 1 Institute for Space Research , Russian Academy of Sciences, Moscow, Russia
| | - A S Kozyrev
- 1 Institute for Space Research , Russian Academy of Sciences, Moscow, Russia
| | - D I Lisov
- 1 Institute for Space Research , Russian Academy of Sciences, Moscow, Russia
| | - A V Malakhov
- 1 Institute for Space Research , Russian Academy of Sciences, Moscow, Russia
| | - M I Mokrousov
- 1 Institute for Space Research , Russian Academy of Sciences, Moscow, Russia
| | - A B Sanin
- 1 Institute for Space Research , Russian Academy of Sciences, Moscow, Russia
| | - V N Shvetsov
- 4 Joint Institute of Nuclear Research , Dubna, Russia
| | | | - T M Tomilina
- 3 A.A. Blagonravov Institute of Mechanical Engineering , Russian Academy of Sciences, Moscow, Russia
| | - V I Tret'yakov
- 1 Institute for Space Research , Russian Academy of Sciences, Moscow, Russia
| | - A A Vostrukhin
- 1 Institute for Space Research , Russian Academy of Sciences, Moscow, Russia
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Boynton WV, Droege GF, Mitrofanov IG, McClanahan TP, Sanin AB, Litvak ML, Schaffner M, Chin G, Evans LG, Garvin JB, Harshman K, Malakhov A, Milikh G, Sagdeev R, Starr R. High spatial resolution studies of epithermal neutron emission from the lunar poles: Constraints on hydrogen mobility. ACTA ACUST UNITED AC 2012. [DOI: 10.1029/2011je003979] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Sanin AB, Mitrofanov IG, Litvak ML, Malakhov A, Boynton WV, Chin G, Droege G, Evans LG, Garvin J, Golovin DV, Harshman K, McClanahan TP, Mokrousov MI, Mazarico E, Milikh G, Neumann G, Sagdeev R, Smith DE, Starr RD, Zuber MT. Testing lunar permanently shadowed regions for water ice: LEND results from LRO. ACTA ACUST UNITED AC 2012. [DOI: 10.1029/2011je003971] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Litvak ML, Mitrofanov IG, Sanin A, Malakhov A, Boynton WV, Chin G, Droege G, Evans LG, Garvin J, Golovin DV, Harshman K, McClanahan TP, Mokrousov MI, Mazarico E, Milikh G, Neumann G, Sagdeev R, Smith DE, Starr R, Zuber MT. Global maps of lunar neutron fluxes from the LEND instrument. ACTA ACUST UNITED AC 2012. [DOI: 10.1029/2011je003949] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Mitrofanov IG, Boynton WV, Litvak ML, Sanin AB, Starr RD. Response to Comment on “Hydrogen Mapping of the Lunar South Pole Using the LRO Neutron Detector Experiment LEND”. Science 2011; 334:1058-d. [DOI: 10.1126/science.1203483] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Affiliation(s)
- I. G. Mitrofanov
- Institute for Space Research of Russian Academy of Science, 117997 Moscow, Russia
| | | | - M. L. Litvak
- Institute for Space Research of Russian Academy of Science, 117997 Moscow, Russia
| | - A. B. Sanin
- Institute for Space Research of Russian Academy of Science, 117997 Moscow, Russia
| | - R. D. Starr
- Catholic University, Washington, DC 20015, USA
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Mitrofanov IG, Sanin AB, Boynton WV, Chin G, Garvin JB, Golovin D, Evans LG, Harshman K, Kozyrev AS, Litvak ML, Malakhov A, Mazarico E, McClanahan T, Milikh G, Mokrousov M, Nandikotkur G, Neumann GA, Nuzhdin I, Sagdeev R, Shevchenko V, Shvetsov V, Smith DE, Starr R, Tretyakov VI, Trombka J, Usikov D, Varenikov A, Vostrukhin A, Zuber MT. Hydrogen mapping of the lunar south pole using the LRO neutron detector experiment LEND. Science 2010; 330:483-6. [PMID: 20966247 DOI: 10.1126/science.1185696] [Citation(s) in RCA: 212] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Hydrogen has been inferred to occur in enhanced concentrations within permanently shadowed regions and, hence, the coldest areas of the lunar poles. The Lunar Crater Observation and Sensing Satellite (LCROSS) mission was designed to detect hydrogen-bearing volatiles directly. Neutron flux measurements of the Moon's south polar region from the Lunar Exploration Neutron Detector (LEND) on the Lunar Reconnaissance Orbiter (LRO) spacecraft were used to select the optimal impact site for LCROSS. LEND data show several regions where the epithermal neutron flux from the surface is suppressed, which is indicative of enhanced hydrogen content. These regions are not spatially coincident with permanently shadowed regions of the Moon. The LCROSS impact site inside the Cabeus crater demonstrates the highest hydrogen concentration in the lunar south polar region, corresponding to an estimated content of 0.5 to 4.0% water ice by weight, depending on the thickness of any overlying dry regolith layer. The distribution of hydrogen across the region is consistent with buried water ice from cometary impacts, hydrogen implantation from the solar wind, and/or other as yet unknown sources.
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Affiliation(s)
- I G Mitrofanov
- Institute for Space Research of the Russian Academy of Science, 117997 Moscow, Russia.
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Mitrofanov IG, Sanin AB, Golovin DV, Litvak ML, Konovalov AA, Kozyrev AS, Malakhov AV, Mokrousov MI, Tretyakov VI, Troshin VS, Uvarov VN, Varenikov AB, Vostrukhin AA, Shevchenko VV, Shvetsov VN, Krylov AR, Timoshenko GN, Bobrovnitsky YI, Tomilina TM, Grebennikov AS, Kazakov LL, Sagdeev RZ, Milikh GN, Bartels A, Chin G, Floyd S, Garvin J, Keller J, McClanahan T, Trombka J, Boynton W, Harshman K, Starr R, Evans L. Experiment LEND of the NASA Lunar Reconnaissance Orbiter for high-resolution mapping of neutron emission of the Moon. Astrobiology 2008; 8:793-804. [PMID: 18844457 DOI: 10.1089/ast.2007.0158] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
The scientific objectives of neutron mapping of the Moon are presented as 3 investigation tasks of NASA's Lunar Reconnaissance Orbiter mission. Two tasks focus on mapping hydrogen content over the entire Moon and on testing the presence of water-ice deposits at the bottom of permanently shadowed craters at the lunar poles. The third task corresponds to the determination of neutron contribution to the total radiation dose at an altitude of 50 km above the Moon. We show that the Lunar Exploration Neutron Detector (LEND) will be capable of carrying out all 3 investigations. The design concept of LEND is presented together with results of numerical simulations of the instrument's sensitivity for hydrogen detection. The sensitivity of LEND is shown to be characterized by a hydrogen detection limit of about 100 ppm for a polar reference area with a radius of 5 km. If the presence of ice deposits in polar "cold traps" is confirmed, a unique record of many millions of years of lunar history would be obtained, by which the history of lunar impacts could be discerned from the layers of water ice and dust. Future applications of a LEND-type instrument for Mars orbital observations are also discussed.
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Affiliation(s)
- I G Mitrofanov
- Institute for Space Research of the Russian Academy of Sciences, Moscow, Russia.
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Litvak ML, Mitrofanov IG, Barmakov YN, Behar A, Bitulev A, Bobrovnitsky Y, Bogolubov EP, Boynton WV, Bragin SI, Churin S, Grebennikov AS, Konovalov A, Kozyrev AS, Kurdumov IG, Krylov A, Kuznetsov YP, Malakhov AV, Mokrousov MI, Ryzhkov VI, Sanin AB, Shvetsov VN, Smirnov GA, Sholeninov S, Timoshenko GN, Tomilina TM, Tuvakin DV, Tretyakov VI, Troshin VS, Uvarov VN, Varenikov A, Vostrukhin A. The Dynamic Albedo of Neutrons (DAN) experiment for NASA's 2009 Mars Science Laboratory. Astrobiology 2008; 8:605-612. [PMID: 18598140 DOI: 10.1089/ast.2007.0157] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
We present a summary of the physical principles and design of the Dynamic Albedo of Neutrons (DAN) instrument onboard NASA's 2009 Mars Science Laboratory (MSL) mission. The DAN instrument will use the method of neutron-neutron activation analysis in a space application to study the abundance and depth distribution of water in the martian subsurface along the path of the MSL rover.
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Affiliation(s)
- M L Litvak
- Space Research Institute, Moscow, Russia.
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Mitrofanov IG, Zuber MT, Litvak ML, Boynton WV, Smith DE, Drake D, Hamara D, Kozyrev AS, Sanin AB, Shinohara C, Saunders RS, Tretyakov V. CO2 snow depth and subsurface water-ice abundance in the northern hemisphere of Mars. Science 2003; 300:2081-4. [PMID: 12829779 DOI: 10.1126/science.1084350] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Observations of seasonal variations of neutron flux from the high-energy neutron detector (HEND) on Mars Odyssey combined with direct measurements of the thickness of condensed carbon dioxide by the Mars Orbiter Laser Altimeter (MOLA) on Mars Global Surveyor show a latitudinal dependence of northern winter deposition of carbon dioxide. The observations are also consistent with a shallow substrate consisting of a layer with water ice overlain by a layer of drier soil. The lower ice-rich layer contains between 50 and 75 weight % water, indicating that the shallow subsurface at northern polar latitudes on Mars is even more water rich than that in the south.
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Affiliation(s)
- I G Mitrofanov
- Space Research Institute, Russian Academy of Sciences, Moscow, 117997, Russia.
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