Research Article

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

Science  11 Dec 1998:
Vol. 282, Issue 5396, pp. 2053-2060
DOI: 10.1126/science.282.5396.2053

You are currently viewing the abstract.

View Full Text

Via your Institution

Log in through your institution

Log in through your institution


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 × 106 to 1.7 × 106cubic 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.

  • * To whom correspondence should be addressed: zuber{at}tharsis.gsfc.nasa.gov

View Full Text

Related Content