Polar caps
Publikation: Bidrag til bog/antologi/rapport › Bidrag til bog/antologi › Forskning › fagfællebedømt
The permanent polar caps of Mars constitute the largest known reservoirs of H 2 O on the planet. The permanent caps are distinguished from the seasonal snow covers that have been known for centuries. The seasonal snow consists of CO 2 that condenses out of the atmosphere in the winter hemisphere [8]. During summer, the seasonal snow cover gradually evaporates, and the permanent cap is exposed. The permanent polar caps are recognisable as topographic domes rising about 3 km above the surrounding terrain. They have an extent of around 1000 km in the north and 400-800 km in the south. They consist of layers of H 2 O, dust and CO 2 that have been deposited through millions of years. Bright white areas indicate a currently active interaction with the Martian climate system. Dark areas reveal an extensive layering thought to preserve a record of climate changes on Mars. The caps may contain preserved samples of biological origin, and geological indications of meltwater may be a clue to subsurface environments where life might exist. The polar regions are thus particularly interesting in relation to the search for life on Mars.
Originalsprog | Engelsk |
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Titel | Advances in Astrobiology and Biogeophysics |
Antal sider | 25 |
Forlag | Springer Verlag |
Publikationsdato | 1 jan. 2005 |
Sider | 129-153 |
DOI | |
Status | Udgivet - 1 jan. 2005 |
Navn | Advances in Astrobiology and Biogeophysics |
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Vol/bind | 4 |
ISSN | 1610-8957 |
ID: 230423103