Comparison of UV Albedo of CO<sub>2</sub> and H<sub>2</sub>O Ices t North and South Poles Perennial Caps - Archive ouverte HAL Access content directly
Conference Papers Year :

Comparison of UV Albedo of CO2 and H2O Ices t North and South Poles Perennial Caps

(1) , (1) , (2) , (1) , (1) , (3)
1
2
3

Abstract

Perennial polar caps appear very bright in visible light images (Viking, MOC, HRSC). This is also true in the UV range from 200 to 300 nm as seen by SPICAM UV spectrometer, where the albedo is found larger by a factor 3 to 4 higher than surrounding areas outside the caps, both on south and north polar caps. On the south polar cap, which was visited first by Mars Express in January 2004, the UV albedo was found to decrease strongly with wavelength from 300 to 200 nm in the bright regions. Since H2O is not suspected to have such a strong slope in that range, this spectral albedo variation seems to be typical either of CO2 ice or of dust mixed in the ice. A comparison with the north polar cap data, which contain only H2O ice, will be useful to better understand the different spectral signatures of the two types of ices in the UV. Also, it appears that in the visible, the albedo of the south polar cap is distinctly lower in peripheral regions of the perennial cap, interpreted as being the sign of dominating dusty H2O ice. A comparison between visible albedo and UV albedo will be presented on both poles.
Not file

Dates and versions

insu-00364599 , version 1 (26-02-2009)

Identifiers

  • HAL Id : insu-00364599 , version 1

Cite

Sébastien Perrier, Jean-Loup Bertaux, Bernard Schmitt, Aurélie Reberac, Emmanuel Dimarellis, et al.. Comparison of UV Albedo of CO2 and H2O Ices t North and South Poles Perennial Caps. First Mars Express Science Conference, ESA/ESTEC, Feb 2005, Noordwijk, Netherlands. ⟨insu-00364599⟩
64 View
0 Download

Share

Gmail Facebook Twitter LinkedIn More