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

Autor:	Maria T. Zuber, Catherine L. Johnson, David E. Smith, T. C. Duxbury, Xiaoli Sun, G. H. Pettengill, H. Jay Zwally, Gregory A. Neumann, Anton B. Ivanov, Oded Aharonson, Herbert Frey, Kathryn E. Fishbaugh, W. Bruce Banerdt, Peter G. Ford, Roger J. Phillips, James B. Abshire, Duane O. Muhleman, Robert S. Afzal, James B. Garvin, Sean C. Solomon, James W. Head
Rok vydání:	1998
Předmět:	Martian Multidisciplinary Extraterrestrial Environment Ice Northern Hemisphere Mars Water Mars Exploration Program Geophysics Carbon Dioxide Astrobiology Atmosphere Mars Orbiter Laser Altimeter Polar Outflow Altimeter Geology
Zdroj:	Science. 282:2053-2060
ISSN:	1095-9203 0036-8075
Popis:	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.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_dedup___::c463a437c23dccba78e17ae90d8798cf https://doi.org/10.1126/science.282.5396.2053 Zobrazit plný text záznamu Plný text ve formátu PDF