Observations of the North Polar Region of Mars from the Mars Orbiter Laser Altimeter

Authors:
  • DSDavid E. Smith
    David E. Smith
  • SSSean C. Solomon
    Sean C. Solomon
  • JAJames B. Abshire
    James B. Abshire
  • RARobert S. Afzal
    Robert S. Afzal
  • KFKathryn Fishbaugh
    Kathryn Fishbaugh
  • PFPeter G. Ford
    Peter G. Ford
  • HFHerbert V. Frey
    Herbert V. Frey
  • JGJames B. Garvin
    James B. Garvin
  • JHJames W. Head
    James W. Head
  • AIAnton B. Ivanov
    Anton B. Ivanov
Publisher website
Google Scholar
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 H 2 O composition. Correlation of topography with images suggests that the cap was more spatially extensive in the past. The cap volume of 1.2 × 10 6 to 1.7 × 10 6 cubic kilometers is about half that of the Greenland ice cap. Clouds observed over the polar cap are likely composed of CO 2 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.

This publication has 32 references indexed in Scilit: