Application of laser induced breakdown spectroscopy (LIBS) to Mars polar exploration : LIBS analysis of water ice and water ice/soil mixtures

• Main Authors: Arp, Z. A., Cremers, D. A., Wiens, R. C.
• Language: unknown
• Published: 2021
• Subjects: 47 OTHER INSTRUMENTATION; 71 CLASSICAL AND QUANTUM MECHANICS; GENERAL PHYSICS; LASER SPECTROSCOPY; MARS PLANET; SURFACE PROPERTIES; ICE; CARBON DIOXIDE; SOIL CHEMISTRY; ABLATION; POLAR REGIONS; MULTI-ELEMENT ANALYSIS; ice core
• Online Access: http://www.osti.gov/servlets/purl/977482; https://www.osti.gov/biblio/977482

The polar regions of Mars are of great interest due to the presence of water ice and CO{sub 2} ice combined with wind blown deposits. Due to seasonal changes and repeated cycles of precipitating dusts and H{sub 2}O, geological samples appear to have built up in the polar regions. These polar layered deposits (PLD) may include volcanic ash, fallout from surface impacts, evaporates from subliming lakes and seas and even wind blown ancient microbial life. The ability to examine the PLDs will be of great importance in the study of past Martian geological history and the determination of the past presence of life on Mars. Analysis of the ice fields which are present in the polar regions of Mars will almost certainly be of great interest to future surface rovers and landers to this region. The use of LIBS will maximize the scientific return of these missions. Through the development of a compact sensor head and a pan and tilt mechanism, analysis of PLD may be made in areas that are otherwise inaccessible to either a lander or a surface rover. This gives LIBS a significant advantage over other analysis techniques which require more than just optical access. Also, through the use of repetitive laser pulses it will be possible to ablate away the water ice layer to better examine the PLDs which exist below the surface. Another potential use for LIBS is the analysis of retrieved ice core samples. Laser pulses formed along the length of the ice core can monitor composition as a function of depth. This method has already been shown to work for mineral drill cores and terrestrial ice cores using laser ablation ICP-MS. Prior work on the use of LIBS for analysis of ice has focused on the detection of trace metal ions in the ice. To our knowledge no further work has been reported on the use of LIBS for analysis of water ice and water ice/soil mixtures. Here we will examine in detail the detection capabilities of LIBS on water ice and water ice/soil mixtures in an atmosphere similar in pressure and composition to that on Mars.