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Huang J, Li Z, Shi D, Chen Y, Yuan K, Hu S, Wang Y. Scanning single-pixel imaging lidar. OPTICS EXPRESS 2022; 30:37484-37492. [PMID: 36258336 DOI: 10.1364/oe.471036] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2022] [Accepted: 09/16/2022] [Indexed: 06/16/2023]
Abstract
Long-range light detection and ranging (lidar) of active illumination optical imaging has widespread applications, such as remote sensing, satellite-based global topography, and target recognition and identification. Here, to make trade-offs among imaging efficiency, resolution, receiving field of view, divergence angle, and detected distance, we demonstrate a scanning single-pixel imaging lidar (SSPIL), enjoying the merits of the traditional pointing-by-pointing scanning imaging and single-pixel imaging. The imaging strategy of SSPIL is divided into scanning search and staring imaging processes. These strategies can save most time consumption for imaging background areas and thus improve imaging efficiency. Three imaging experiments were conducted in real urban atmospheric conditions. The preliminary results show SSPIL has the ability for long-range imaging with high efficiency, high resolution, and a large receiving field of view. Also, from the imaging results, we found that multiple samples can improve the SNR of imaging in the real urban atmosphere. The present work may provide a valuable alternative approach in the long-range active illumination optical imaging fields.
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Šrámek O, Zhong S. Long-wavelength stagnant lid convection with hemispheric variation in lithospheric thickness: Link between Martian crustal dichotomy and Tharsis? ACTA ACUST UNITED AC 2010. [DOI: 10.1029/2010je003597] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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3
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Heet TL, Arvidson RE, Cull SC, Mellon MT, Seelos KD. Geomorphic and geologic settings of the Phoenix Lander mission landing site. ACTA ACUST UNITED AC 2009. [DOI: 10.1029/2009je003416] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Ansan V, Mangold N, Masson P, Gailhardis E, Neukum G. Topography of valley networks on Mars from Mars Express High Resolution Stereo Camera digital elevation models. ACTA ACUST UNITED AC 2008. [DOI: 10.1029/2007je002986] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Arvidson R, Adams D, Bonfiglio G, Christensen P, Cull S, Golombek M, Guinn J, Guinness E, Heet T, Kirk R, Knudson A, Malin M, Mellon M, McEwen A, Mushkin A, Parker T, Seelos F, Seelos K, Smith P, Spencer D, Stein T, Tamppari L. Mars Exploration Program 2007 Phoenix landing site selection and characteristics. ACTA ACUST UNITED AC 2008. [DOI: 10.1029/2007je003021] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Hiesinger H, Head JW, Neukum G. Young lava flows on the eastern flank of Ascraeus Mons: Rheological properties derived from High Resolution Stereo Camera (HRSC) images and Mars Orbiter Laser Altimeter (MOLA) data. ACTA ACUST UNITED AC 2007. [DOI: 10.1029/2006je002717] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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8
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Bulmer MH, Petley DN, Murphy W, Mantovani F. Detecting slope deformation using two-pass differential interferometry: Implications for landslide studies on Earth and other planetary bodies. ACTA ACUST UNITED AC 2006. [DOI: 10.1029/2005je002593] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Hiesinger H. The Syrtis Major volcanic province, Mars: Synthesis from Mars Global Surveyor data. ACTA ACUST UNITED AC 2004. [DOI: 10.1029/2003je002143] [Citation(s) in RCA: 144] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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11
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Ghatan GJ. Cavi Angusti, Mars: Characterization and assessment of possible formation mechanisms. ACTA ACUST UNITED AC 2003. [DOI: 10.1029/2002je001972] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Wyatt MB. Analysis of surface compositions in the Oxia Palus region on Mars from Mars Global Surveyor Thermal Emission Spectrometer Observations. ACTA ACUST UNITED AC 2003. [DOI: 10.1029/2002je001986] [Citation(s) in RCA: 12] [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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14
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Carr MH. Oceans on Mars: An assessment of the observational evidence and possible fate. ACTA ACUST UNITED AC 2003. [DOI: 10.1029/2002je001963] [Citation(s) in RCA: 234] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Kreslavsky MA, Head JW. Fate of outflow channel effluents in the northern lowlands of Mars: The Vastitas Borealis Formation as a sublimation residue from frozen ponded bodies of water. ACTA ACUST UNITED AC 2002. [DOI: 10.1029/2001je001831] [Citation(s) in RCA: 138] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Mikhail A. Kreslavsky
- Department of Geological Sciences; Brown University; Providence Rhode Island USA
- Kharkov Astronomical Observatory; Kharkov Ukraine
| | - James W. Head
- Department of Geological Sciences; Brown University; Providence Rhode Island USA
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Affiliation(s)
- Robert A. Craddock
- Center for Earth and Planetary Studies, National Air and Space Museum; Smithsonian Institution; Washington District of Columbia USA
| | - Alan D. Howard
- Department of Environmental Sciences; University of Virginia; Charlottesville Virginia USA
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Ghatan GJ. Candidate subglacial volcanoes in the south polar region of Mars: Morphology, morphometry, and eruption conditions. ACTA ACUST UNITED AC 2002. [DOI: 10.1029/2001je001519] [Citation(s) in RCA: 107] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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19
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Scott ED. Plinian eruptions and passive collapse events as mechanisms of formation for Martian pit chain craters. ACTA ACUST UNITED AC 2002. [DOI: 10.1029/2000je001432] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Head JW. Northern lowlands of Mars: Evidence for widespread volcanic flooding and tectonic deformation in the Hesperian Period. ACTA ACUST UNITED AC 2002. [DOI: 10.1029/2000je001445] [Citation(s) in RCA: 204] [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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21
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Scott ED. Emplacement of giant radial dikes in the northern Tharsis region of Mars. ACTA ACUST UNITED AC 2002. [DOI: 10.1029/2000je001431] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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22
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Williams RME, Phillips RJ. Morphometric measurements of martian valley networks from Mars Orbiter Laser Altimeter (MOLA) data. ACTA ACUST UNITED AC 2001. [DOI: 10.1029/2000je001409] [Citation(s) in RCA: 79] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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23
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Titus TN, Kieffer HH, Mullins KF, Christensen PR. TES premapping data: Slab ice and snow flurries in the Martian north polar night. ACTA ACUST UNITED AC 2001. [DOI: 10.1029/2000je001284] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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24
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Smith DE, Zuber MT, Frey HV, Garvin JB, Head JW, Muhleman DO, Pettengill GH, Phillips RJ, Solomon SC, Zwally HJ, Banerdt WB, Duxbury TC, Golombek MP, Lemoine FG, Neumann GA, Rowlands DD, Aharonson O, Ford PG, Ivanov AB, Johnson CL, McGovern PJ, Abshire JB, Afzal RS, Sun X. Mars Orbiter Laser Altimeter: Experiment summary after the first year of global mapping of Mars. ACTA ACUST UNITED AC 2001. [DOI: 10.1029/2000je001364] [Citation(s) in RCA: 1152] [Impact Index Per Article: 50.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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25
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Thomson BJ, Head JW. Utopia Basin, Mars: Characterization of topography and morphology and assessment of the origin and evolution of basin internal structure. ACTA ACUST UNITED AC 2001. [DOI: 10.1029/2000je001355] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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26
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Neumann GA, Rowlands DD, Lemoine FG, Smith DE, Zuber MT. Crossover analysis of Mars Orbiter Laser Altimeter data. ACTA ACUST UNITED AC 2001. [DOI: 10.1029/2000je001381] [Citation(s) in RCA: 122] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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27
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Stewart EM, Head JW. Ancient Martian volcanoes in the Aeolis region: New evidence from MOLA data. ACTA ACUST UNITED AC 2001. [DOI: 10.1029/2000je001322] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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28
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Head JW, Pratt S. Extensive Hesperian-aged south polar ice sheet on Mars: Evidence for massive melting and retreat, and lateral flow and ponding of meltwater. ACTA ACUST UNITED AC 2001. [DOI: 10.1029/2000je001359] [Citation(s) in RCA: 190] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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29
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Sakimoto SEH, Gregg TKP. Channeled flow: Analytic solutions, laboratory experiments, and applications to lava flows. ACTA ACUST UNITED AC 2001. [DOI: 10.1029/2000jb900384] [Citation(s) in RCA: 42] [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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30
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Kreslavsky MA, Head JW. Kilometer-scale roughness of Mars: Results from MOLA data analysis. ACTA ACUST UNITED AC 2000. [DOI: 10.1029/2000je001259] [Citation(s) in RCA: 278] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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31
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Fishbaugh KE, Head JW. North polar region of Mars: Topography of circumpolar deposits from Mars Orbiter Laser Altimeter (MOLA) data and evidence for asymmetric retreat of the polar cap. ACTA ACUST UNITED AC 2000. [DOI: 10.1029/1999je001230] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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32
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Pavlov AA, Kasting JF, Brown LL, Rages KA, Freedman R. Greenhouse warming by CH4 in the atmosphere of early Earth. JOURNAL OF GEOPHYSICAL RESEARCH 2000; 105:11981-90. [PMID: 11543544 DOI: 10.1029/1999je001134] [Citation(s) in RCA: 412] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Earth appears to have been warm during its early history despite the faintness of the young Sun. Greenhouse warming by gaseous CO2 and H2O by itself is in conflict with constraints on atmospheric CO2 levels derived from paleosols for early Earth. Here we explore whether greenhouse warming by methane could have been important. We find that a CH4 mixing ratio of 10(-4) (100 ppmv) or more in Earth's early atmosphere would provide agreement with the paleosol data from 2.8 Ga. Such a CH4 concentration could have been readily maintained by methanogenic bacteria, which are thought to have been an important component of the biota at that time. Elimination of the methane component of the greenhouse by oxidation of the atmosphere at about 2.3-2.4 Ga could have triggered the Earth's first widespread glaciation.
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Affiliation(s)
- A A Pavlov
- Department of Geosciences, Pennsylvania State University, University Park, USA.
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33
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Abshire JB, Sun X, Afzal RS. Mars orbiter laser altimeter: receiver model and performance analysis. APPLIED OPTICS 2000; 39:2449-2460. [PMID: 18345159 DOI: 10.1364/ao.39.002449] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
The design, calibration, and performance of the Mars Orbiter Laser Altimeter (MOLA) receiver are described. The MOLA measurements include the range to the surface, which is determined by the laser-pulse time of flight; the height variability within the footprint determined by the laser echo pulse width; and the apparent surface reflectivity determined by the ratio of the echo to transmitted pulse energies.
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Hiesinger H, Head JW. Characteristics and origin of polygonal terrain in southern Utopia Planitia, Mars: Results from Mars Orbiter Laser Altimeter and Mars Orbiter Camera data. ACTA ACUST UNITED AC 2000. [DOI: 10.1029/1999je001193] [Citation(s) in RCA: 90] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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35
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Zuber MT, Solomon SC, Phillips RJ, Smith DE, Tyler GL, Aharonson O, Balmino G, Banerdt WB, Head JW, Johnson CL, Lemoine FG, McGovern PJ, Neumann GA, Rowlands DD, Zhong S. Internal structure and early thermal evolution of Mars from Mars Global Surveyor topography and gravity. Science 2000; 287:1788-93. [PMID: 10710301 DOI: 10.1126/science.287.5459.1788] [Citation(s) in RCA: 457] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Topography and gravity measured by the Mars Global Surveyor have enabled determination of the global crust and upper mantle structure of Mars. The planet displays two distinct crustal zones that do not correlate globally with the geologic dichotomy: a region of crust that thins progressively from south to north and encompasses much of the southern highlands and Tharsis province and a region of approximately uniform crustal thickness that includes the northern lowlands and Arabia Terra. The strength of the lithosphere beneath the ancient southern highlands suggests that the northern hemisphere was a locus of high heat flow early in martian history. The thickness of the elastic lithosphere increases with time of loading in the northern plains and Tharsis. The northern lowlands contain structures interpreted as large buried channels that are consistent with northward transport of water and sediment to the lowlands before the end of northern hemisphere resurfacing.
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Affiliation(s)
- M T Zuber
- Department of Earth, Atmospheric, and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
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36
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Edgett KS, Malin MC. New views of Mars eolian activity, materials, and surface properties: Three vignettes from the Mars Global Surveyor Mars Orbiter Camera. ACTA ACUST UNITED AC 2000. [DOI: 10.1029/1999je001152] [Citation(s) in RCA: 125] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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37
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Head JW, Hiesinger H, Ivanov MA, Kreslavsky MA, Pratt S, Thomson BJ. Possible ancient oceans on Mars: evidence from Mars Orbiter Laser Altimeter data. Science 1999; 286:2134-7. [PMID: 10591640 DOI: 10.1126/science.286.5447.2134] [Citation(s) in RCA: 306] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
High-resolution altimetric data define the detailed topography of the northern lowlands of Mars, and a range of data is consistent with the hypothesis that a lowland-encircling geologic contact represents the ancient shoreline of a large standing body of water present in middle Mars history. The contact altitude is close to an equipotential line, the topography is smoother at all scales below the contact than above it, the volume enclosed by this contact is within the range of estimates of available water on Mars, and a series of extensive terraces parallel the contact in many places.
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Affiliation(s)
- J W Head
- Department of Geological Sciences, Brown University, Providence, RI 02912, USA
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38
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Hinson DP, Simpson RA, Twicken JD, Tyler GL, Flasar FM. Initial results from radio occultation measurements with Mars Global Surveyor. ACTA ACUST UNITED AC 1999. [DOI: 10.1029/1999je001069] [Citation(s) in RCA: 224] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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39
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Lewis SR, Collins M, Read PL, Forget F, Hourdin F, Fournier R, Hourdin C, Talagrand O, Huot JP. A climate database for Mars. ACTA ACUST UNITED AC 1999. [DOI: 10.1029/1999je001024] [Citation(s) in RCA: 267] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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40
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Sakimoto SEH, Frey HV, Garvin JB, Roark JH. Topography, roughness, layering, and slope properties of the Medusae Fossae Formation from Mars Orbiter Laser Altimeter (MOLA) and Mars Orbiter Camera (MOC) data. ACTA ACUST UNITED AC 1999. [DOI: 10.1029/1999je001044] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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41
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Smith DE, Sjogren WL, Tyler GL, Balmino G, Lemoine FG, Konopliv AS. The gravity field of Mars: results from Mars Global Surveyor. Science 1999; 286:94-7. [PMID: 10506567 DOI: 10.1126/science.286.5437.94] [Citation(s) in RCA: 113] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Observations of the gravity field of Mars reveal a planet that has responded differently in its northern and southern hemispheres to major impacts and volcanic processes. The rough, elevated southern hemisphere has a relatively featureless gravitational signature indicating a state of near-isostatic compensation, whereas the smooth, low northern plains display a wider range of gravitational anomalies that indicates a thinner but stronger surface layer than in the south. The northern hemisphere shows evidence for buried impact basins, although none large enough to explain the hemispheric elevation difference. The gravitational potential signature of Tharsis is approximately axisymmetric and contains the Tharsis Montes but not the Olympus Mons or Alba Patera volcanoes. The gravity signature of Valles Marineris extends into Chryse and provides an estimate of material removed by early fluvial activity.
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Affiliation(s)
- D E Smith
- Laboratory for Terrestrial Physics, National Aeronautics and Space Administration (NASA) Goddard Space Flight Center, Greenbelt, MD 20771, USA.
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42
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Kreslavsky MA, Head JW. Kilometer-scale slopes on Mars and their correlation with geologic units: Initial results from Mars Orbiter Laser Altimeter (MOLA) data. ACTA ACUST UNITED AC 1999. [DOI: 10.1029/1999je001051] [Citation(s) in RCA: 83] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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43
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Hansen GB. Control of the radiative behavior of the Martian polar caps by surface CO2ice: Evidence from Mars Global Surveyor measurements. ACTA ACUST UNITED AC 1999. [DOI: 10.1029/1998je000626] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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44
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Smith DE, Zuber MT, Solomon SC, Phillips RJ, Head JW, Garvin JB, Banerdt WB, Muhleman DO, Pettengill GH, Neumann GA, Lemoine FG, Abshire JB, Aharonson O, Brown CD, Hauck SA, Ivanov AB, McGovern PJ, Zwally HJ, Duxbury TC. The global topography of Mars and implications for surface evolution. Science 1999; 284:1495-503. [PMID: 10348732 DOI: 10.1126/science.284.5419.1495] [Citation(s) in RCA: 714] [Impact Index Per Article: 28.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Elevations measured by the Mars Orbiter Laser Altimeter have yielded a high-accuracy global map of the topography of Mars. Dominant features include the low northern hemisphere, the Tharsis province, and the Hellas impact basin. The northern hemisphere depression is primarily a long-wavelength effect that has been shaped by an internal mechanism. The topography of Tharsis consists of two broad rises. Material excavated from Hellas contributes to the high elevation of the southern hemisphere and to the scarp along the hemispheric boundary. The present topography has three major drainage centers, with the northern lowlands being the largest. The two polar cap volumes yield an upper limit of the present surface water inventory of 3.2 to 4.7 million cubic kilometers.
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Affiliation(s)
- D E Smith
- Earth Sciences Directorate, NASA/Goddard Space Flight Center, Greenbelt, MD 20771, USA.
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45
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Chapman MG, Kargel JS. Observations at the Mars Pathfinder site: Do they provide “unequivocal” evidence of catastrophic flooding? ACTA ACUST UNITED AC 1999. [DOI: 10.1029/98je02083] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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46
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Zeitler W, Oberst J. The Mars Pathfinder landing site and the Viking control point network. ACTA ACUST UNITED AC 1999. [DOI: 10.1029/98je01430] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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47
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Davis WL, McKay CP, Hynes SF. Remote sensing for organics on Mars. ADVANCES IN SPACE RESEARCH : THE OFFICIAL JOURNAL OF THE COMMITTEE ON SPACE RESEARCH (COSPAR) 1999; 24:489-496. [PMID: 11543336 DOI: 10.1016/s0273-1177(99)00083-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The detection of organics on Mars remains an important scientific objective. Advances in instrumentation and laboratory techniques provide new insight into the lower level detection limit of complex organics in closely packed media. Preliminary results demonstrate that algae present in a palagonite medium do exhibit a spectral reflectance feature in the visible range for dry mass weight ratios of algae to palagonite greater than 6%--which corresponds to 30 mg algae in a 470 mg (just optically thick (< 3 mm) layer) palagonite matrix. This signature most probably represents chlorophyll a, a light harvesting pigment with an emission peak at 678 nm.
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Affiliation(s)
- W L Davis
- SETI Institute, NASA Ames Research Center, Moffett Field, CA 94035, USA
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48
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Smith DE, Zuber MT, Haberle RM, Rowlands DD, Murphy JR. The Mars seasonal CO2cycle and the time variation of the gravity field: A general circulation model simulation. ACTA ACUST UNITED AC 1999. [DOI: 10.1029/1998je900024] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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49
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Zuber MT, Smith DE, Solomon SC, Abshire JB, Afzal RS, Aharonson O, Fishbaugh K, Ford PG, Frey HV, Garvin JB, Head JW, Ivanov AB, Johnson CL, Muhleman DO, Neumann GA, Pettengill GH, Phillips RJ, Sun X, Zwally HJ, Banerdt WB, Duxbury TC. Observations of the north polar region of Mars from the Mars orbiter laser altimeter. Science 1998; 282:2053-60. [PMID: 9851922 DOI: 10.1126/science.282.5396.2053] [Citation(s) in RCA: 189] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Elevations from the Mars Orbiter Laser Altimeter (MOLA) have been used to construct a precise topographic map of the martian north polar region. The northern ice cap has a maximum elevation of 3 kilometers above its surroundings but lies within a 5-kilometer-deep hemispheric depression that is contiguous with the area into which most outflow channels emptied. Polar cap topography displays evidence of modification by ablation, flow, and wind and is consistent with a primarily H2O composition. Correlation of topography with images suggests that the cap was more spatially extensive in the past. The cap volume of 1.2 x 10(6) to 1.7 x 10(6) cubic kilometers is about half that of the Greenland ice cap. Clouds observed over the polar cap are likely composed of CO2 that condensed out of the atmosphere during northern hemisphere winter. Many clouds exhibit dynamical structure likely caused by the interaction of propagating wave fronts with surface topography.
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Affiliation(s)
- M T Zuber
- Department of Earth, Atmospheric, and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
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Abstract
The Mars Global Surveyor (MGS) spacecraft achieved a 45-hour elliptical orbit at Mars on 11 September 1997 after an 11-month cruise from Earth. The mission is acquiring high-quality global observations of the martian surface and atmosphere and of its magnetic and gravitational fields. These observations will continue for one martian year.
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Affiliation(s)
- A L Albee
- California Institute of Technology, Pasadena, CA, 91125, USA
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