Publication Date:
2009-07-04
Description:
The Wet Chemistry Laboratory on the Phoenix Mars Lander performed aqueous chemical analyses of martian soil from the polygon-patterned northern plains of the Vastitas Borealis. The solutions contained approximately 10 mM of dissolved salts with 0.4 to 0.6% perchlorate (ClO4) by mass leached from each sample. The remaining anions included small concentrations of chloride, bicarbonate, and possibly sulfate. Cations were dominated by Mg2+ and Na+, with small contributions from K+ and Ca2+. A moderately alkaline pH of 7.7 +/- 0.5 was measured, consistent with a carbonate-buffered solution. Samples analyzed from the surface and the excavated boundary of the approximately 5-centimeter-deep ice table showed no significant difference in soluble chemistry.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Hecht, M H -- Kounaves, S P -- Quinn, R C -- West, S J -- Young, S M M -- Ming, D W -- Catling, D C -- Clark, B C -- Boynton, W V -- Hoffman, J -- Deflores, L P -- Gospodinova, K -- Kapit, J -- Smith, P H -- New York, N.Y. -- Science. 2009 Jul 3;325(5936):64-7. doi: 10.1126/science.1172466.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA. michael.h.hecht@jpl.nasa.gov〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/19574385" target="_blank"〉PubMed〈/a〉
Keywords:
*Anions
;
*Cations
;
Chemical Phenomena
;
Extraterrestrial Environment
;
Hydrogen-Ion Concentration
;
*Mars
;
Oxidation-Reduction
;
*Perchlorates
;
Solubility
;
Spacecraft
;
Temperature
;
Water
Print ISSN:
0036-8075
Electronic ISSN:
1095-9203
Topics:
Biology
,
Chemistry and Pharmacology
,
Computer Science
,
Medicine
,
Natural Sciences in General
,
Physics
