title: Search for life on Mars:  evaluation of techniques.
abstract: An important question for exobiology is, did life evolve on Mars?  To answer this question, experiments must be conducted on the martian surface.  Given current mission constraints on mass, power, and volume, these experiments can only be performed using proposed analytical techniques such as: electron microscopy, X-ray fluorescence, X-ray diffraction, alpha-proton backscatter, gamma-ray spectrometry, differential thermal analysis, differential scanning calorimetry, pyrolysis gas chromatography, mass spectrometry, and specific element detectors.  Using prepared test samples consisting of 1% organic matter (bovine serum albumin) in palagonite and a mixture of palagonite, clays, iron oxides, and evaporites, it was determined that a combination of X-ray diffraction and differential thermal analysis coupled with gas chromatography provides the best insight into the chemistry, mineralogy, and geological history of the samples.
authors.affiliation: SETI Institute, NASA Ames Research Center, Moffett Field, CA 94035-1000, USA.
authors.forename: D E
authors.initials: DE
authors.lastname: Schwartz
authors.forename: R L
authors.initials: RL
authors.lastname: Mancinelli
authors.forename: M R
authors.initials: MR
authors.lastname: White
mesh_terms: D000538:Aluminum Silicates / Q000032:analysis; D002254:Carbonates / Q000032:analysis; D002623:Chemistry Techniques, Analytical / Q000379:methods*; D002849:Chromatography, Gas; D000077215:Clay; D005069:Evaluation Studies as Topic; D018559:Exobiology / Q000379:methods*; D019015:Geologic Sediments / Q000032:analysis*; D005898:Glass / Q000032:analysis; D018535:Mars; D012107:Research Design; D012987:Soil / Q000032:analysis; D013026:Space Flight / Q000295:instrumentation; D014961:X-Ray Diffraction
chemical_list: D000538:Aluminum Silicates; D002254:Carbonates; D012987:Soil; D000077215:Clay