Publication Date:
2002-06-01
Description:
Using the Gamma-Ray Spectrometer on the Mars Odyssey, we have identified two regions near the poles that are enriched in hydrogen. The data indicate the presence of a subsurface layer enriched in hydrogen overlain by a hydrogen-poor layer. The thickness of the upper layer decreases with decreasing distance to the pole, ranging from a column density of about 150 grams per square centimeter at -42 degrees latitude to about 40 grams per square centimeter at -77 degrees. The hydrogen-rich regions correlate with regions of predicted ice stability. We suggest that the host of the hydrogen in the subsurface layer is ice, which constitutes 35 +/- 15% of the layer by weight.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Boynton, W V -- Feldman, W C -- Squyres, S W -- Prettyman, T H -- Bruckner, J -- Evans, L G -- Reedy, R C -- Starr, R -- Arnold, J R -- Drake, D M -- Englert, P A J -- Metzger, A E -- Mitrofanov, Igor -- Trombka, J I -- D'Uston, C -- Wanke, H -- Gasnault, O -- Hamara, D K -- Janes, D M -- Marcialis, R L -- Maurice, S -- Mikheeva, I -- Taylor, G J -- Tokar, R -- Shinohara, C -- New York, N.Y. -- Science. 2002 Jul 5;297(5578):81-5. Epub 2002 May 30.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Lunar and Planetary Laboratory, University of Arizona, Tucson, AZ 85721, USA. wboynton@lpl.arizona.edu〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/12040090" target="_blank"〉PubMed〈/a〉
Keywords:
Atmosphere
;
Dry Ice
;
Extraterrestrial Environment
;
Gamma Rays
;
*Hydrogen
;
*Ice
;
*Mars
;
Models, Theoretical
;
Neutrons
;
Spacecraft
;
Spectrometry, Gamma
;
Spectrum Analysis
;
Water
Print ISSN:
0036-8075
Electronic ISSN:
1095-9203
Topics:
Biology
,
Chemistry and Pharmacology
,
Computer Science
,
Medicine
,
Natural Sciences in General
,
Physics
