Mars Orbiter Laser Altimeter: Experiment summary after the first year of global mapping of Mars

The Mars Orbiter Laser Altimeter (MOLA), an instrument on the Mars Global Surveyor spacecraft, has measured the topography, surface roughness, and 1.064-μm reflectivity of Mars and the heights of volatile and dust clouds. This paper discusses the function of the MOLA instrument and the acquisition, processing, and correction of observations to produce global data sets. The altimeter measurements have been converted to both gridded and spherical harmonic models for the topography and shape of Mars that have vertical and radial accuracies of ~1 m with respect to the planet's center of mass. The current global topographic grid has a resolution of 1/64° in latitude × 1/32° in longitude (1 × 2 km^2 at the equator). Reconstruction of the locations of incident laser pulses on the Martian surface appears to be at the 100-m spatial accuracy level and results in 2 orders of magnitude improvement in the global geodetic grid of Mars. Global maps of optical pulse width indicative of 100-m-scale surface roughness and 1.064-μm reflectivity with an accuracy of 5% have also been obtained.

[1]  Robert Blair Vocci.  Geology , 1882, Nature.

[2]  G S Levy,et al.  Occultation Experiment: Results of the First Direct Measurement of Mars's Atmosphere and Ionosphere , 1965, Science.

[3]  E. Opik,et al.  The Martian Surface , 1966, Science.

[4]  P. Gierasch,et al.  A study of the thermal and dynamical structure of the martian lower atmosphere , 1968 .

[5]  Charles C. Counselman,et al.  Radar measurements of Martian topography. , 1969 .

[6]  Y. Mintz,et al.  Numerical Simulation of the Atmospheric Circulation and Climate of Mars , 1969 .

[7]  G. Pettengill,et al.  Radar Measurements of the Surface Topography and Roughness of Mars , 1970 .

[8]  R. Goldstein,et al.  Preliminary radar results of Mars. , 1970 .

[9]  Robert B. Leighton,et al.  The Surface of Mars , 2007 .

[10]  L. Soderblom,et al.  The surface of Mars 2. Uncratered terrains , 1971 .

[11]  A E Rogers,et al.  Martian Craters and a Scarp as Seen by Radar , 1971, Science.

[12]  R. Goldstein,et al.  Mars Radar Observations, a Preliminary Report , 1971, Science.

[13]  A. Kliore,et al.  The atmosphere of Mars from Mariner 9 radio occultation measurements. , 1972 .

[14]  C. Hord.  Mariner 6 and 7 ultraviolet spectrometer experiment: Photometry and topography of mars , 1972 .

[15]  A. Lane,et al.  Mariner 9 Ultraviolet Spectrometer Experiment: Photometry and Topography of Mars (A 3. 6) , 1972 .

[16]  G. Schubert,et al.  Evidence for convection in planetary interiors from first-order topography , 1973 .

[17]  T. E. Burke,et al.  Atmospheric and surface properties of Mars obtained by infrared spectroscopy on Mariner 9. , 1973 .

[18]  P. Woiceshyn,et al.  S band radio occultation measurements of the atmosphere and topography of Mars with Mariner 9: Extended mission coverage of polar and intermediate latitudes , 1973 .

[19]  Robert P. Sharp,et al.  Mars: Fretted and chaotic terrains , 1973 .

[20]  Alan E. E. Rogers,et al.  Topography and radar scattering properties of Mars , 1973 .

[21]  J. F. Jordan,et al.  Gravity Field of Mars from Mariner 9 Tracking Data (A. 6.2 and A. 6. 1) , 1973 .

[22]  W. Ward.  Climatic variations on Mars: 1. Astronomical theory of insolation , 1974 .

[23]  G. Hulme,et al.  The Interpretation of Lava Flow Morphology , 1974 .

[24]  Thomas A. Mutch,et al.  Geology of Mars , 1977 .

[25]  R. R. Green,et al.  Radar measurements of Martian topography and surface properties - The 1971 and 1973 oppositions , 1975 .

[26]  R Greeley,et al.  North Polar Region of Mars: Imaging Results from Viking 2 , 1976, Science.

[27]  Terry Z. Martin,et al.  Thermal and albedo mapping of Mars during the Viking primary mission , 1977 .

[28]  R. Greeley,et al.  Martian impact craters and emplacement of ejecta by surface flow , 1977 .

[29]  Bruce G. Bills,et al.  Mars topography harmonics and geophysical implications , 1978 .

[30]  M. Davies.  The control net of Mars: May 1977 , 1978 .

[31]  L. Soderblom,et al.  Possible fossil H2O liquid-ice interfaces in the Martian crust , 1978 .

[32]  A. Şengör,et al.  Relative timing of rifting and volcanism on earth and its tectonic implications , 1978 .

[33]  P. E. Reichley,et al.  Radar studies of the Martian surface at centimeter wavelengths: The 1975 opposition , 1978 .

[34]  Matthew P. Golombek,et al.  Tharsis province of Mars: Geologic sequence, geometry, and a deformation mechanism , 1979 .

[35]  W. H. Michael,et al.  Viking radio occultation measurements of the atmosphere and topography of Mars: Data acquired during 1 Martian year of tracking , 1979 .

[36]  P. Komar.  Comparisons of the hydraulics of water flows in Martian outflow channels with flows of similar scale on earth , 1979 .

[37]  M. Golombek,et al.  Tectonic evolution of Mars , 1979 .

[38]  M. Steckler,et al.  Observations of flexure and the state of stress in the oceanic lithosphere , 1980 .

[39]  G. S. Downs,et al.  Radar altimetry of South Tharsis, Mars , 1980 .

[40]  R. L. Duncombe,et al.  Report of the IAU Working Group on Cartographic Coordinates and Rotational Elements of the Planets and Satellites , 1980 .

[41]  Richard J. Pike,et al.  Control of crater morphology by gravity and target type - Mars, earth, moon , 1980 .

[42]  James W. Head,et al.  Volcanism on Mars , 1981, Nature.

[43]  R. J. Willemann,et al.  Role of membrane stresses in the support of planetary topography , 1981 .

[44]  The Olympus Mons Paradox: why Hasn't the Martian Lithosphere Failed Under the Load? , 1981 .

[45]  M. Carr,et al.  Martian channels and valleys: Their characteristics, distribution, and age , 1981 .

[46]  L. Soderblom,et al.  Mars' global properties: maps and applications. , 1982 .

[47]  Sean C. Solomon,et al.  Evolution of the Tharsis Province of Mars: The importance of heterogeneous lithospheric thickness and volcanic construction , 1982 .

[48]  C. Gardner,et al.  Target signatures for laser altimeters: an analysis. , 1982, Applied optics.

[49]  Roger J. Phillips,et al.  Thick shell tectonics on one-plate planets - Applications to Mars , 1982 .

[50]  T. W. Thompson,et al.  New radar‐derived topography for the northern hemisphere of Mars , 1982 .

[51]  D. Campbell,et al.  Dual-polarization radar observations of Mars: Tharsis and Environs , 1982 .

[52]  M. Davies,et al.  The 1982 Control Network of Mars , 1983 .

[53]  Steven W. Squyres,et al.  The martian hemispheric dichotomy may be due to a giant impact , 1984, Nature.

[54]  W. Peltier,et al.  Pleistocene deglaciation and the Earth's rotation: a new analysis , 1984 .

[55]  M. Kobrick,et al.  Venus topography:a harmonic analysis , 1985 .

[56]  Steven J. Ostro,et al.  Mars - Dual-polarization radar observations with extended coverage , 1985 .

[57]  Sean C. Solomon,et al.  Mars: Thickness of the lithosphere from the tectonic response to volcanic loads , 1985 .

[58]  B. Tapley,et al.  Geographically correlated orbit error and its effect on satellite altimetry missions , 1985 .

[59]  Roger J. Phillips,et al.  Gravity and lithospheric stress on the terrestrial planets with reference to the Tharsis Region of Mars , 1985 .

[60]  D. H. Scott,et al.  GEOLOGIC MAP OF THE WESTERN EQUATORIAL REGION OF MARS , 1986 .

[61]  M. Golombek,et al.  Origin of planetary wrinkle ridges based on the study of terrestrial analogs , 1986 .

[62]  P. Christensen.  Regional dust deposits on Mars - Physical properties, age, and history , 1986 .

[63]  Ronald Greeley,et al.  Geologic map of the eastern equatorial region of Mars , 1987 .

[64]  P. Masson.  The Geology of Mars , 1987 .

[65]  Michael H. Carr,et al.  Water on Mars , 1987, Nature.

[66]  Robert L. Byer,et al.  Diode Laser—Pumped Solid-State Lasers , 1988, Science.

[67]  R. Arvidson,et al.  Accumulation of Sedimentary Debris in the South Polar Region of Mars and Implications for Climate History , 1988 .

[68]  Richard A. Schultz,et al.  Large impact basins and the mega-impact origin for the crustal dichotomy on Mars , 1988 .

[69]  P. Schultz,et al.  Sequence and mechanisms of deformation around the Hellas and Isidis Impact Basins on Mars , 1989 .

[70]  Thomas C. Duxbury,et al.  The figure of Phobos , 1989 .

[71]  G. Mcgill.  Buried topography of Utopia, Mars: Persistence of a giant impact depression , 1989 .

[72]  Nadine G. Barlow,et al.  Martian impact craters: Correlations of ejecta and interior morphologies with diameter, latitude, and terrain , 1990 .

[73]  Walter H. F. Smith,et al.  Gridding with continuous curvature splines in tension , 1990 .

[74]  Sean C. Solomon,et al.  Heterogeneities in the thickness of the elastic lithosphere of Mars - Constraints on heat flow and internal dynamics , 1990 .

[75]  C. Shum,et al.  Altimeter crossover methods for precision orbit determination and the mapping of geophysical parameters , 1990 .

[76]  Alain Soufflot,et al.  ISM observations of Mars and PHOBOS - First results , 1990 .

[77]  R. Strom,et al.  Ancient glaciation on Mars , 1990 .

[78]  Robert M. Haberle,et al.  Simulations of the general circulation of the Martian atmosphere: 1. Polar processes , 1990 .

[79]  H. Frey,et al.  A new survey of multiring impact basins on Mars , 1990 .

[80]  Tilman Spohn,et al.  Thermal history of Mars and the sulfur content of its core , 1990 .

[81]  V. R. Baker,et al.  Ancient oceans, ice sheets and the hydrological cycle on Mars , 1991, Nature.

[82]  Kenneth L. Tanaka,et al.  Reconciliation of stress and structural histories of the Tharsis region of Mars , 1991 .

[83]  Design and performance of an autonomous tracking system for the Mars observer laser altimeter receiver , 1991 .

[84]  Topographic maps of the polar, western, and eastern regions of Mars , 1991 .

[85]  Chester S. Gardner,et al.  Ranging performance of satellite laser altimeters , 1992, IEEE Trans. Geosci. Remote. Sens..

[86]  P. K. Seidelmann,et al.  Report of the IAU/IAG/COSPAR working group on cartographic coordinates and rotational elements of the planets and satellites: 1991 , 1992 .

[87]  Frederic M. Davidson,et al.  Receiver characteristics of laser altimeters with avalanche photodiodes , 1992 .

[88]  J. Pollack,et al.  Dynamics of the atmosphere of Mars , 1992 .

[89]  D. Muhleman,et al.  Radar determination of Mars surface properties , 1992 .

[90]  William D. Smythe,et al.  The Opposition Effect of the Moon: Coherent BackscatterandShadow Hiding , 1998 .

[91]  J. Pollack,et al.  Mars - Epochal climate change and volatile history , 1992 .

[92]  H. J. Moore,et al.  The Martian surface layer , 1992 .

[93]  David E. Smith,et al.  Radio science investigations with Mars Observer , 1992 .

[94]  James B. Abshire,et al.  Mars Observer laser altimeter investigation , 1993, Defense, Security, and Sensing.

[95]  David C. Pieri,et al.  Coastal Geomorphology of the Martian northern plains , 1993 .

[96]  Stephane Erard,et al.  The surface of Syrtis Major - Composition of the volcanic substrate and mixing with altered dust and soil , 1993 .

[97]  Stephen M. Clifford,et al.  A model for the hydrologic and climatic behavior of water on Mars , 1993 .

[98]  T. Watters.  Compressional tectonism on Mars , 1993 .

[99]  Alfred S. McEwen,et al.  Lunar impact basins: New data for the western limb and far side (Orientale and South Pole‐Aitken Basins) from the first Galileo flyby , 1993 .

[100]  S. Solomon,et al.  State of stress, faulting, and eruption characteristics of large volcanoes on Mars , 1993 .

[101]  Robert M. Haberle,et al.  Simulations of the general circulation of the Martian Atmosphere: 2. Seasonal pressure variations , 1993 .

[102]  S. Squyres,et al.  Early Mars: How Warm and How Wet? , 1993, Science.

[103]  J. Bufton,et al.  Optical system design and integration of the Mars Observer Laser Altimeter. , 1994, Applied optics.

[104]  J. Head,et al.  Mars: review and analysis of volcanic eruption theory and relationships to observed landforms. , 1994 .

[105]  David E. Smith,et al.  The Shape and Internal Structure of the Moon from the Clementine Mission , 1994, Science.

[106]  Kenneth L. Tanaka,et al.  Lithospheric-scale buckling and thrust structures on Mars: The Coprates rise and south Tharsis ridge belt , 1994 .

[107]  R. Afzal,et al.  Mars Observer Laser Altimeter: laser transmitter. , 1994, Applied optics.

[108]  N. Sleep.  Martian plate tectonics , 1994 .

[109]  David A. Paige,et al.  Thermal and albedo mapping of the polar regions of Mars using Viking thermal mapper observations: 1. North polar region , 1994 .

[110]  Paul D. Spudis,et al.  Ancient Multiring Basins on the Moon Revealed by Clementine Laser Altimetry , 1994, Science.

[111]  The orientation of future JPL Planetary Ephemerides , 1995 .

[112]  Remo Guidieri.  Res , 1995, RES: Anthropology and Aesthetics.

[113]  Steven M. Klosko,et al.  The temporal and spatial characteristics of TOPEX/POSEIDON radial orbit error , 1995 .

[114]  Preliminary Cartographic Analysis of the Pathfinder Landing Site Using Viking Orbiter Images , 1995 .

[115]  David E. Smith,et al.  Mars without Tharsis , 1995 .

[116]  J. Pollack,et al.  Low brightness temperatures of Martian polar caps : CO2 clouds or low surface emissivity ? , 1995 .

[117]  M. Zuber.  Wrinkle Ridges, Reverse Faulting, and the Depth Penetration of Lithospheric Strain in Lunae Planum, Mars , 1995 .

[118]  Kenneth L. Tanaka,et al.  Extension across Tempe Terra, Mars, from measurements of fault scarp widths and deformed craters , 1996 .

[119]  David E. Smith,et al.  The Shape of Mars and the Topographic Signature of the Hemispheric Dichotomy , 1996, Science.

[120]  Detection and monitoring of H2O and CO2 ice clouds on Mars , 1996 .

[121]  H. J. Moore,et al.  Overview of the Mars Pathfinder mission and assessment of landing site predictions. , 1997, Science.

[122]  Tilman Spohn,et al.  The interior structure of Mars: Implications from SNC meteorites , 1997 .

[123]  V. Baker,et al.  Paleohydrology and flood geomorphology of Ares Vallis , 1997 .

[124]  W. Folkner,et al.  Interior structure and seasonal mass redistribution of Mars from radio tracking of Mars Pathfinder. , 1997, Science.

[125]  H. J. Moore,et al.  Selection of the Mars Pathfinder landing site , 1997 .

[126]  David E. Smith,et al.  Topography of the Moon from the Clementine lidar , 1997 .

[127]  S. Solomon,et al.  Filling of flexural moats around large volcanoes on Venus: Implications for volcano structure and global magmatic flux , 1997 .

[128]  M. Zuber.  Mars Orbiter Laser Altimeter , 1997 .

[129]  David E. Smith,et al.  The NEAR laser ranging investigation , 1997 .

[130]  Sean C. Solomon,et al.  Localization of gravity and topography: constraints on the tectonics and mantle dynamics of Venus , 1997 .

[131]  M. T. Boies,et al.  The Near-Earth Asteroid Rendezvous Laser Altimeter , 1997 .

[132]  The Role of Viscous Deformation in the Morphology of the Martian North Polar Cap , 1998 .

[133]  Olivier Grasset,et al.  Thermal convection in a volumetrically heated, infinite Prandtl number fluid with strongly temperature‐dependent viscosity: Implications for planetary thermal evolution , 1998 .

[134]  Kevin K. Williams,et al.  Measurement and Analysis of Lunar Basin Depths from Clementine Altimetry , 1998 .

[135]  David E. Smith,et al.  The relationship between MOLA northern hemisphere topography and the 6.1‐Mbar atmospheric pressure surface of Mars , 1998 .

[136]  Maria T. Zuber,et al.  Mars: Northern hemisphere slopes and slope distributions , 1998 .

[137]  The MOLA Topographic signature at the crustal dichotomy boundary zone on Mars , 1998 .

[138]  J W Head,et al.  Topography of the northern hemisphere of Mars from the Mars Orbiter Laser Altimeter. , 1998, Science.

[139]  A. Albee,et al.  Mars global surveyor mission: overview and status. , 1998, Science.

[140]  David E. Smith,et al.  Oceans in the past history of Mars: Tests for their presence using Mars Orbiter Laser Altimeter (MOLA) data , 1998 .

[141]  M E Davies,et al.  Early views of the martian surface from the Mars Orbiter Camera of Mars Global Surveyor. , 1998, Science.

[142]  Detection of Lava Flow Unit Thicknesses and Characteristics on Mars: First Results from Mars Orbiter Laser Altimeter (MOLA) Data , 1998 .

[143]  G. Pettengill,et al.  Observations of the north polar region of Mars from the Mars orbiter laser altimeter. , 1998, Science.

[144]  D. Muhleman,et al.  Opacity of the Martian atmosphere from the Mars Orbiter Laser Altimeter (MOLA) observations , 1998 .

[145]  David E. Smith,et al.  Shape of the northern hemisphere of Mars from the Mars Orbiter Laser Altimeter (MOLA) , 1998 .

[146]  D. Harding,et al.  Observations of the Earth's topography from the Shuttle Laser Altimeter (SLA): Laser-pulse Echo-recovery measurements of terrestrial surfaces , 1998 .

[147]  Extension Across Tempe Terra, Mars from MOLA Topographic Measurements , 1999 .

[148]  David E. Smith,et al.  The global topography of Mars and implications for surface evolution. , 1999, Science.

[149]  Recent and Ancient Flood Lavas on Mars , 1999 .

[150]  Paul E. Johnson,et al.  Infrared Spectral Imaging of Martian Clouds and Ices , 1999 .

[151]  K. Herkenhoff,et al.  Dark material in the polar layered deposits and dunes on Mars , 1999 .

[152]  Frank G. Lemoine,et al.  Orbit Determination for Mars Global Surveyor During Mapping , 1999 .

[153]  Ness,et al.  Global distribution of crustal magnetization discovered by the mars global surveyor MAG/ER experiment , 1999, Science.

[154]  James W. Head,et al.  Kilometer‐scale slopes on Mars and their correlation with geologic units: Initial results from Mars Orbiter Laser Altimeter (MOLA) data , 1999 .

[155]  M. Malin,et al.  Oceans or seas in the Martian northern lowlands: High resolution imaging tests of proposed coastlines , 1999 .

[156]  J W Head,et al.  Possible ancient oceans on Mars: evidence from Mars Orbiter Laser Altimeter data. , 1999, Science.

[157]  H. Frey,et al.  Discovery of a 450 km diameter, multi‐ring basin on Mars through analysis of MOLA topographic data , 1999 .

[158]  J. Bell,et al.  Near-Infrared Imaging of Mars from HST: Surface Reflectance, Photometric Properties, and Implications for MOLA Data , 1999 .

[159]  David P. Hinson,et al.  Initial results from radio occultation measurements with Mars Global Surveyor , 1999 .

[160]  Frank G. Lemoine,et al.  The use of laser altimetry in the orbit and attitude determination of Mars Global Surveyor , 1999 .

[161]  J. Oberst,et al.  The Mars Pathfinder landing site and the Viking control point network , 1999 .

[162]  Alba Patera, Mars: Characterization Using Mars Orbiter Laser Altimeter (MOLA) Data and Comparison with Other Volcanic Edifices , 1999 .

[163]  W. Durham,et al.  Steady‐state flow of solid CO2: Preliminary results , 1999 .

[164]  Ness,et al.  Magnetic lineations in the ancient crust of mars , 1999, Science.

[165]  M. Malin,et al.  Flow rates and duration within Kasei Valles, Mars: Implications for the formation of a Martian Ocean , 1999 .

[166]  J. Garvin,et al.  Vertical roughness of Mars from the Mars Orbiter Laser Altimeter , 1999 .

[167]  Driving Stresses in Mars Polar Ice Caps and Conditions for Ice Flow , 1999 .

[168]  G. Balmino,et al.  The gravity field of Mars: results from Mars Global Surveyor. , 1999, Science.

[169]  G. A. Neumann,et al.  The Topography (and Ephemeris) of Phobos from MOLA Ranging , 2000 .

[170]  J. Head,et al.  Characteristics and origin of polygonal terrain in southern Utopia Planitia, Mars: Results from Mars Orbiter Laser Altimeter and Mars Orbiter Camera data , 2000 .

[171]  R. Arrell.  Implications of Martian polar insolation levels on the climatic cycling of volatiles , 2000 .

[172]  Detailed Topographic Structure of the Isidis Impact Basin from MOLA Data , 2000 .

[173]  Anton B. Ivanov,et al.  The Role of Sublimation for the Formation of the Northern Ice Cap: Results from the Mars Orbiter Laser Altimeter , 2000 .

[174]  M. Golombek,et al.  Tectonics of the Tharsis Region of Mars: Insights from MGS Topography and Gravity , 2000 .

[175]  Joshua L. Bandfield,et al.  A Global View of Martian Surface Compositions from MGS-TES , 2000 .

[176]  M. Malin,et al.  Evidence for recent groundwater seepage and surface runoff on Mars. , 2000, Science.

[177]  J. Abshire,et al.  Mars orbiter laser altimeter: receiver model and performance analysis. , 2000, Applied optics.

[178]  Zuber,et al.  The shape of 433 eros from the NEAR-shoemaker laser rangefinder , 2000, Science.

[179]  Peter G. Ford,et al.  Winter clouds over the North Martian Polar Cap , 2000 .

[180]  M. Zuber,et al.  Degree-1 mantle convection and the crustal dichotomy on Mars , 2000 .

[181]  J. Garvin,et al.  Topographic Evidence for Geologically Recent Near-Polar Volcanism on Mars , 2000 .

[182]  James W. Head,et al.  Kilometer‐scale roughness of Mars: Results from MOLA data analysis , 2000 .

[183]  James B. Garvin,et al.  North Polar Region Craterforms on Mars: Geometric Characteristics from the Mars Orbiter Laser Altimeter , 2000 .

[184]  J. Head,et al.  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 , 2000 .

[185]  L. A. Soderblom,et al.  North–south geological differences between the residual polar caps on Mars , 2000, Nature.

[186]  John C. Pearl,et al.  Mars Global Surveyor Thermal Emission Spectrometer (TES) observations of dust opacity during aerobraking and science phasing , 2000 .

[187]  David E. Smith,et al.  Lithospheric Loading by the Northern Polar Cap on Mars , 2000 .

[188]  A Large Population of Possible Buried Impact Basins on Mars Revealed by MOLA Topographic Data , 2000 .

[189]  J W Head,et al.  Internal structure and early thermal evolution of Mars from Mars Global Surveyor topography and gravity. , 2000, Science.

[190]  F. Nimmo,et al.  Influence of early plate tectonics on the thermal evolution and magnetic field of Mars , 2000 .

[191]  Extensive South Polar Ice Cap in Middle Mars History?: Tests Using MOLA Data , 2000 .

[192]  J. M. Moore,et al.  The Instability of a South Polar Cap on Mars Composed of Carbon Dioxide , 2000 .

[193]  Jeffrey S. Lavell,et al.  Report on the Loss of the Mars Polar Lander and Deep Space 2 Missions , 2000 .

[194]  Frederik J. Simons,et al.  Isostatic response of the Australian lithosphere: Estimation of effective elastic thickness and anisotropy using multitaper spectral analysis , 2000 .

[195]  G. Leonard Tyler,et al.  Radio science observations with Mars Global Surveyor: Orbit insertion through one Mars year in mapping orbit , 2001 .

[196]  M. Zuber,et al.  Martian wrinkle ridge topography: Evidence for subsurface faults from MOLA , 2001 .

[197]  F. Nimmo,et al.  Estimates of Martian crustal thickness from viscous relaxation of topography , 2001 .

[198]  Extension and uplift at Alba Patera, Mars: Insights from MOLA observations and loading models , 2001 .

[199]  G. Neumann,et al.  Enigmatic northern plains of Mars , 2001, Nature.

[200]  R. Phillips,et al.  Mars' volatile and climate history , 2001, Nature.

[201]  Daniel H. Rothman,et al.  Statistics of Mars' topography from the Mars Orbiter Laser Altimeter: Slopes, correlations, and physical Models , 2001 .

[202]  V. Baker.  Water and the martian landscape , 2001, Nature.

[203]  Frank G. Lemoine,et al.  An improved solution of the gravity field of Mars (GMM‐2B) from Mars Global Surveyor , 2001 .

[204]  Maria T. Zuber,et al.  The crust and mantle of Mars , 2001, Nature.

[205]  D. Stevenson.  Mars' core and magnetism , 2001, Nature.

[206]  R. Phillips,et al.  Evidence for extensive denudation of the Martian highlands , 2001 .

[207]  M. Mellon,et al.  Mars Global Surveyor Thermal Emission Spectrometer experiment: Investigation description and surface science results , 2001 .

[208]  H. C. Williams,et al.  Power laws: Are hospital waiting lists self-regulating? , 2001, Nature.

[209]  David E. Smith,et al.  Ancient Geodynamics and Global-Scale Hydrology on Mars , 2001, Science.

[210]  Raymond E. Arvidson,et al.  Overview of the Mars Global Surveyor mission , 2001 .

[211]  David E. Smith,et al.  Crossover analysis of Mars Orbiter Laser Altimeter data , 2001 .

[212]  J. Head,et al.  Ancient Martian volcanoes in the Aeolis region: New evidence from MOLA data , 2001 .

[213]  Dah-Ning Yuan,et al.  Gravity field of Mars: A 75th Degree and Order Model , 2001 .