14:40 〜 14:55
[MIS03-04] Analytical Advancements in Extraterrestrial Life Detection Targeting Mars Return Samples
NASA's Perseverance Rover completed sampling of rocks, regoliths and air in combination with blanks to trace terrestrial contamination. As International missions for the recovery and return of the collected samples are planned to initiate in 2027, analytical frameworks involved in life detection from the returned samples are developed (Kminek, Suzuki et al. 2022). Along with the recent development, challenges for the detection of extraterrestrial life became clearly recognized:
1) The selection of analytical instruments is limited by the practicality in biosafety level 4 laboratories.
2) As the applicability of biological methods is limited to non-terrestrial life, rock and ligolith characterizations must be combined with biological characterization to statistically determine the presence/absence of extraterrestrial life.
3) There is a knowledge gap in the validity and applicability of the analytical methods assumed to detect life in returned samples (e.g. effects of rock matrix and rock age).
In this study, basaltic rock, a prominent rock type at the Martian surface, was selected. Rock core samples previously characterized by high sensitivity, low specificity analytical instruments not feasibly applicable to biosafety level 4 laboratories such as nanoscale secondary ion mass spectrometry (NanoSIMS) and high angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) were subjected to analysis by infrared red spectroscopy as an alternate in Biosafety Level 4 laboratories. Fourier Transform IR (FT-IR) analysis of reference materials including various types of clay minerals, archaeal and bacterial cultures and biomolecules (DNA, proteins, lipids) was performed to clarify diagnostic signals. By using bulk FT-IR information, thin sections of the rock core samples with clay-filled fractures were subjected to in-situ analysis using optical-photothermal infrared spectroscopy (O-PTIR). It was revealed that Fe/Mg-smectite and microbial cells identified by HARDF-STEM and NanoSIMS analyses were resolved by O-PTIR analysis. However, it was found that O-PTIR is based on thermal expansion inducted by laser bombardment, which hindered to obtain diagnostic signals from minerals grains of serpentine-group minerals. In the presentation, in-situ FT-IR analysis targeting life detection from regolith samples will be presented.
Kminek, G., Benardini, JM., Brenker, FE., Brooks, T., Burton, AS., Dhaniyala, S., Dworkin, JP., Fortman, JL., Glamoclija, M., Grady, MM., Graham, HV., Haruyama, J., Kieft., TL., Koopmans, M., McCubbin, FM., Meyer, MA., Mustin, C., Onstott, TC., Pearce, Z., Pratt, LM., Sephton, MA., Siljeström, S., Sugahara, H., Suzuki, S., Suzuki, Y., Zuilen Mv., & Viso, M. (2022) COSPAR Sample Safety Assessment Framework (SSAF). Astrobiology 22, S1, doi.org/10.1089/ast.2022.0017.
1) The selection of analytical instruments is limited by the practicality in biosafety level 4 laboratories.
2) As the applicability of biological methods is limited to non-terrestrial life, rock and ligolith characterizations must be combined with biological characterization to statistically determine the presence/absence of extraterrestrial life.
3) There is a knowledge gap in the validity and applicability of the analytical methods assumed to detect life in returned samples (e.g. effects of rock matrix and rock age).
In this study, basaltic rock, a prominent rock type at the Martian surface, was selected. Rock core samples previously characterized by high sensitivity, low specificity analytical instruments not feasibly applicable to biosafety level 4 laboratories such as nanoscale secondary ion mass spectrometry (NanoSIMS) and high angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) were subjected to analysis by infrared red spectroscopy as an alternate in Biosafety Level 4 laboratories. Fourier Transform IR (FT-IR) analysis of reference materials including various types of clay minerals, archaeal and bacterial cultures and biomolecules (DNA, proteins, lipids) was performed to clarify diagnostic signals. By using bulk FT-IR information, thin sections of the rock core samples with clay-filled fractures were subjected to in-situ analysis using optical-photothermal infrared spectroscopy (O-PTIR). It was revealed that Fe/Mg-smectite and microbial cells identified by HARDF-STEM and NanoSIMS analyses were resolved by O-PTIR analysis. However, it was found that O-PTIR is based on thermal expansion inducted by laser bombardment, which hindered to obtain diagnostic signals from minerals grains of serpentine-group minerals. In the presentation, in-situ FT-IR analysis targeting life detection from regolith samples will be presented.
Kminek, G., Benardini, JM., Brenker, FE., Brooks, T., Burton, AS., Dhaniyala, S., Dworkin, JP., Fortman, JL., Glamoclija, M., Grady, MM., Graham, HV., Haruyama, J., Kieft., TL., Koopmans, M., McCubbin, FM., Meyer, MA., Mustin, C., Onstott, TC., Pearce, Z., Pratt, LM., Sephton, MA., Siljeström, S., Sugahara, H., Suzuki, S., Suzuki, Y., Zuilen Mv., & Viso, M. (2022) COSPAR Sample Safety Assessment Framework (SSAF). Astrobiology 22, S1, doi.org/10.1089/ast.2022.0017.