Celestial Mechanics and Dynamical Astronomy, 82, 83–110. Report of the IAU/IAG Working Group on Cartographic Coordinates and Rotational Elements of the Planets and Satellites-2000. Journal of Geophysical Research, 108(E4), 5023. Two Mars years of clouds detected by the Mars Orbiter Laser Altimeter. Crossover analysis of Mars Orbiter Laser Altimeter data. National Aeronautics and Space Administration (NASA) Jet Propulsion Laboratory (JPL) (2010). An Improved Solution of the Gravity Field of Mars (GMM-2B) from Mars Global Surveyor. Planetary mapping (274-275), Cambridge, UK: Cambridge University Press. Paper presented at Joint International Symposium on Geospatial Theory, Processing and Applications: ISPRS Commission IV Proceedings, Working Group 9-Extraterrestrial Mapping, Proceedings, International Society for Photogrammetry and Remote Sensing, Ottawa, Canada. Mars Geodesy/Cartography Working Group recommendations on Mars cartographic constants and coordinate systems. Journal of Geophysical Research, 78, 4395–4404. Overview of the Mars Global Surveyor mission. These data provided evidence of cloud coverage and atmospheric variations (NASA JPL, 2010).Īlbee, A. In June 2001, part of the laser reached the end of its life, but a sensor continued to detect changes in surface brightness in the near infrared part of the spectrum. The MOLA showed seasonal changes in the height of the Martian surface (such as snow depth) that represented the first direct global measurement of the amount and distribution of condensed carbon dioxide.
The instrument detected the heights of clouds and identified dynamic features in the atmosphere, such as gravity waves (NASA JPL, 2010). Data from the laser altimeter identified pathways for the flow of past water and the locations, sizes, and volumes of watersheds. The MOLA created the most accurate global topographic map of any planet in the solar system, giving scientists elevation maps precise to within about 30 centimeters (1 foot) in the vertical dimension. After nearly a decade of discovery, MGS went silent in November, 2006 (NASA JPL, 2010). MGS arrived at Mars in September, 1997 and has contributed a multitude of findings, including signs of past, persistent water such as an ancient delta and currently active water features in the gullies of canyon walls. After a 20-year absence at the planet, MGS ushered in a new era of Mars exploration with its five science investigations (NASA JPL, 2010) The thirdstage Star 48B solid rocket later propelled the spacecraft out of Earth orbit and on its way to Mars. MGS launched on Novematop a three-stage Delta II launch vehicle from launch pad 17A at Cape Canaveral Air Station, FL. mission launched to Mars since the Viking mission in 1976 (Albee et al., 2001). (2) The radius, still as a sphere, has been updated to conform to the IAU 2000 definition for Mars 3396190.0 m. (1) The polar gaps from 88 to 90 north and south have been filled by reprojecting polar PDS releases. This version is slightly updated from the original PDS (GeoScience Node) MOLA release. Pixel resolution is 463 meters per pixel (m). However, the total elevation uncertainty is at least ☓ m due to the global error in the areoid (☑.8 meters Neumann et al., 2001) and regional uncertainties in its shape (Neumann, 2002). The average accuracy of each point is originally ~100 meters in horizontal position and ~1 meter in radius (Neumann et al., 2001). These have been converted to elevations above the areoid as determined from a Martian gravity field solution GMM-2B (Lemoine et al., 2001), truncated to degree and order 50, and oriented according to current standards. The MOLA DEM represents more than 600 million measurements gathered between 19, adjusted for consistency (Neumann et al., 2001 Neumann, Smith & Zuber, 2003) and converted to planetary radii. This digital elevation model (DEM) is based on data from the Mars Orbiter Laser Altimeter (MOLA Smith et al., 2001), an instrument on NASA’s Mars Global Surveyor (MGS) spacecraft (Albee et al., 2001).
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