Search for life on Mars: evaluation of techniques

Area of Science:

• Exobiology and Astrobiology
• Planetary Science
• Geochemistry

Background:

• Determining if life evolved on Mars is a key exobiological question.
• Surface experiments are necessary to answer this question, but are limited by mission constraints.
• Analytical techniques must be carefully selected for Martian exploration.

Purpose of the Study:

• To evaluate various analytical techniques for their effectiveness in analyzing Martian surface samples.
• To identify the optimal combination of techniques for assessing sample chemistry, mineralogy, and geological history.

Main Methods:

• Tested analytical techniques including electron microscopy, X-ray fluorescence, X-ray diffraction, and gas chromatography.
• Utilized prepared test samples: 1% organic matter (bovine serum albumin) in palagonite, and a mixture of palagonite, clays, iron oxides, and evaporites.

Main Results:

• A combination of X-ray diffraction and differential thermal analysis (DTA) proved effective.
• Coupling X-ray diffraction, DTA, and gas chromatography provided the most comprehensive data.
• These methods offered significant insight into sample chemistry, mineralogy, and geological history.

Conclusions:

• X-ray diffraction, differential thermal analysis, and gas chromatography are recommended for future Mars missions.
• This technique combination offers the best approach for analyzing Martian samples under current mission constraints.
• Successful analysis of Martian samples is crucial for addressing the question of past life on Mars.