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4. Subsistence of ice-covered lakes during the Hesperian at Gale crater, Mars

Author

Kling, Alexandre M., Haberle, Robert M., McKay, Christopher P., Bristow, Thomas F., and Rivera-Hernandez, Frances

Subjects
Astrophysics - Earth and Planetary Astrophysics
Abstract

Sedimentary deposits characterized by the Mars Science Laboratory Curiosity rover provide evidence that Gale crater, Mars intermittently hosted a fluvio-lacustrine environment during the Hesperian. However, estimates of the CO2 content of the atmosphere at the time the sediments in Gale crater were deposited are far less than needed by any climate model to maintain temperatures warm enough for sustained open water lake conditions due to the low solar energy input available at that time. We incrementally test the existence of open water conditions using energy balance calculations for the global, regional, and seasonal temperatures, and we assess if the preservation of liquid water was possible under perennial ice covers. We found scenarios where lacustrine conditions are preserved in a cold climate, where the resupply of water by the inflow of rivers and high precipitation rates are substituted by an abutting glacier. For equatorial temperatures as low as 240K-255K, the ice thickness ranges from 3-10 m, a value comparable to the range of those for the perennially ice-covered lakes in Antarctica (3-6 m). The ice-covered lake hypothesis is a compelling way to decouple the mineralogy and the climate by limiting the gas exchanges between the sediment and the CO2 atmosphere, and it eliminates the requirement for global mean temperatures above the freezing point. Not only do ice-covered lakes provide a baseline for exploring the range of possible lake scenarios for Gale crater during the Hesperian that is fully consistent with climate studies, but also they might have been ideal environments to sustain life on Mars.

Published
2019
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6. Contribution of soil bacteria to the atmosphere across biomes

Author

Archer, Stephen D.J., Lee, Kevin C., Caruso, Tancredi, Alcami, Antonio, Araya, Jonathan G., Cary, S. Craig, Cowan, Don A., Etchebehere, Claudia, Gantsetseg, Batdelger, Gomez-Silva, Benito, Hartery, Sean, Hogg, Ian D., Kansour, Mayada K., Lawrence, Timothy, Lee, Charles K., Lee, Patrick K.H., Leopold, Matthias, Leung, Marcus H.Y., Maki, Teruya, McKay, Christopher P., Al Mailem, Dina M., Ramond, Jean-Baptiste, Rastrojo, Alberto, Šantl-Temkiv, Tina, Sun, Henry J., Tong, Xinzhao, Vandenbrink, Bryan, Warren-Rhodes, Kimberley A., and Pointing, Stephen B.

Published
2023
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9. Process Safety in the Pharmaceutical Industry: A Selection of Illustrative Case Studies

Author

Dunn, Anna L., Payne, Andrew, Clark, Peter R., McKay, Christopher, Williams, Glynn D., Wheelhouse, Katherine, Arendt, Kevin, Dixon, Frank, and Shilcrat, Susan

Abstract

Awareness of best safety practices in the industrial sector will allow students in chemistry and chemical engineering programs to apply these approaches to their own safety assessments. Process safety is a critical function within the pharmaceutical industry to ensure safety when performing reactions. An introduction to process safety and a series of case studies illustrating how safety is routinely considered within the pharmaceutical industry is presented. The concepts presented herein are applicable to multiple industries, academic research, and chemical reactions conducted on all scales. The case studies include examples where a synthesis was redesigned to afford a triazole intermediate without forming potentially explosive byproducts, an exothermic reaction was controlled by understanding the heat output with time and developing a portion-wise addition procedure, and a reaction that displayed extremely fast gas evolution was managed by using an alternative solvent and controlling the rate of reagent addition.

Published
2021
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11. Meteorological data from Badwater, Death Valley National Park 1998 to 2019.

Author

McKay, Christopher P.

Subjects
*RADIATIVE corrections, *ATMOSPHERIC temperature, *THERMISTORS, *TEMPERATURE measurements, *DATA libraries
Abstract

We installed a meteorological recording system at Badwater (elev. −75 m), the lowest point in Death Valley, California and recorded data over the period 1998–2019. A second station (the Outhouse Station) was established nearby from 2014 to 2019. Here, we report on and publicly archive the data from these two stations. Of interest was the comparison between two air temperature measurements at the Badwater Station, the first with an aspirated platinum resistance temperature device and the second with a thermistor probe in a passive sun shield. During the hottest periods of the summer when temperatures were typically between 30°C at night and 50°C daily peak, the passively shielded sensor indicated up to 0.5°C warmer than the aspirated temperature sensor due to radiative effects. The data suggest a correction for radiative heating of (T–35)/30, for T > 35°C, where, T, is the uncorrected temperature reading of a passively shielded sensor subtracted after any calibration at lower temperatures. Our station was the first precision temperature measurements at Badwater. A longer record exists for the reporting station near the visitor's centre at the Furnace Creek. The summer temperature maxima at the Badwater site correlate well with the values the same day from the Furnace Creek site. The daily maximum temperatures in winter at the Badwater site appear to be about 1°C lower than at the Furnace Creek site. The largest differences are in the minimum temperatures for which the Badwater site averages about 2–3°C warmer than the Furnace Creek site. [ABSTRACT FROM AUTHOR]

Published
2024
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12. Transitory microbial habitat in the hyperarid Atacama Desert

Author

Schulze-Makuch, Dirk, Wagner, Dirk, Kounaves, Samuel P, Mangelsdorf, Kai, Devine, Kevin G, de Vera, Jean-Pierre, Schmitt-Kopplin, Philippe, Grossart, Hans-Peter, Parro, Victor, Kaupenjohann, Martin, Galy, Albert, Schneider, Beate, Airo, Alessandro, Frösler, Jan, Davila, Alfonso F, Arens, Felix L, Cáceres, Luis, Cornejo, Francisco Solís, Carrizo, Daniel, Dartnell, Lewis, DiRuggiero, Jocelyne, Flury, Markus, Ganzert, Lars, Gessner, Mark O, Grathwohl, Peter, Guan, Lisa, Heinz, Jacob, Hess, Matthias, Keppler, Frank, Maus, Deborah, McKay, Christopher P, Meckenstock, Rainer U, Montgomery, Wren, Oberlin, Elizabeth A, Probst, Alexander J, Sáenz, Johan S, Sattler, Tobias, Schirmack, Janosch, Sephton, Mark A, Schloter, Michael, Uhl, Jenny, Valenzuela, Bernardita, Vestergaard, Gisle, Wörmer, Lars, and Zamorano, Pedro

Subjects
Bacteria, Biodiversity, Desert Climate, Ecosystem, Soil, Soil Microbiology, South America, habitat, aridity, microbial activity, biomarker, Mars
Abstract

Traces of life are nearly ubiquitous on Earth. However, a central unresolved question is whether these traces always indicate an active microbial community or whether, in extreme environments, such as hyperarid deserts, they instead reflect just dormant or dead cells. Although microbial biomass and diversity decrease with increasing aridity in the Atacama Desert, we provide multiple lines of evidence for the presence of an at times metabolically active, microbial community in one of the driest places on Earth. We base this observation on four major lines of evidence: (i) a physico-chemical characterization of the soil habitability after an exceptional rain event, (ii) identified biomolecules indicative of potentially active cells [e.g., presence of ATP, phospholipid fatty acids (PLFAs), metabolites, and enzymatic activity], (iii) measurements of in situ replication rates of genomes of uncultivated bacteria reconstructed from selected samples, and (iv) microbial community patterns specific to soil parameters and depths. We infer that the microbial populations have undergone selection and adaptation in response to their specific soil microenvironment and in particular to the degree of aridity. Collectively, our results highlight that even the hyperarid Atacama Desert can provide a habitable environment for microorganisms that allows them to become metabolically active following an episodic increase in moisture and that once it decreases, so does the activity of the microbiota. These results have implications for the prospect of life on other planets such as Mars, which has transitioned from an earlier wetter environment to today's extreme hyperaridity.

Published
2018

15. Contributors

Author

Benardini, J. Nick, primary, Berea, Anamaria, additional, Camprubi, Eloi, additional, Candian, Alessandra, additional, Carneiro, Jéssica, additional, Chan, Queenie Hoi Shan, additional, Cleaves, H. James, additional, Cockell, Charles S., additional, Ditzler, Mark Adam, additional, Dixit, J., additional, Gustafson, Kevin, additional, Haqq-Misra, Jacob, additional, Herts, Richard, additional, Jagtap, S.S., additional, Kaur, K., additional, Lee, Michael D., additional, Lin, Ying, additional, Liu, Rongrong, additional, Markovitch, Omer, additional, Marlow, Jeffrey, additional, McKay, Christopher P., additional, Méndez, Abel, additional, Moissl-Eichinger, Christine, additional, Muchowska, Kamila B., additional, Otto, Sijbren, additional, Perl, Scott M., additional, Petrignani, Annemieke, additional, Popović, Milena, additional, Profitiliotis, George, additional, Santiago, Ma. Francesca, additional, Seyler, Lauren M., additional, ten Kate, Inge Loes, additional, Thombre, R.S., additional, Tiwari, Satyam, additional, Vaishampayan, P.V., additional, Yazıcı, Ayşe Meriç, additional, Zajkowski, Tomasz, additional, and Zolensky, Michael E., additional

Published
2022
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17. Synthetic biological circuit tested in spaceflight

Author

Kitto, Rebekah Z., Dhillon, Yadvender, Bevington, James, Horne, Mera, Giegé, Philippe, Drouard, Laurence, Heintz, Dimitri, Villette, Claire, Corre, Nicolas, Arrivé, Mathilde, Manefield, Michael J, Bowman, Robert, Favier, Jean-Jacques, Osborne, Barnaby, Welch, Chris, McKay, Christopher P., and Hammond, Ming C.

Published
2021
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18. Ammonia or methanol would enable subsurface liquid water in the Martian South Pole

Author

Egea-González, Isabel, McKay, Christopher P., Hallsworth, John E., Jiménez-Díaz, Alberto, Ruiz, Javier, Egea-González, Isabel, McKay, Christopher P., Hallsworth, John E., Jiménez-Díaz, Alberto, and Ruiz, Javier

Abstract

The notion of liquid water beneath the ice layer at the south polar layered deposits of Mars is an interesting possibility given the implications for astrobiology, and possible human habitation. A body of liquid water located at a depth of 1.5 km has been inferred from radar data in the South Polar Cap. However, the high temperatures that would facilitate the existence of liquid water or brine at that depth are not consistent with estimations of heat flow that are based on the lithosphere's flexure. Attempts to reconcile both issues have been inconclusive or otherwise unsuccessful. Here, we analyse the possible role of subsurface ammonia and methanol in maintaining water in a liquid state at subsurface temperatures that are compatible with the lithosphere strength. Our results indicate that the presence of these compounds at the base of the south polar layered deposits can reconcile the existence of liquid water with previous estimations of surface heat flow.

Published
2024

22. In Situ Real-Time Monitoring for Aseptic Drilling: Lessons Learned from the Atacama Rover Astrobiology Drilling Studies Contamination Control Strategy and Implementation and Application to the Icebreaker Mars Life Detection Mission

Author

Bonaccorsi, Rosalba, primary, Glass, Brian, additional, Moreno-Paz, Mercedes, additional, García-Villadangos, Miriam, additional, Warren-Rhodes, Kimberley, additional, Parro, Victor, additional, Manchado, Juan Manuel, additional, Wilhelm, Mary Beth, additional, and McKay, Christopher P., additional

Published
2023
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23. Evidence for indigenous nitrogen in sedimentary and aeolian deposits from the Curiosity rover investigations at Gale crater, Mars.

Author

Stern, Jennifer, Sutter, Brad, Freissinet, Caroline, Navarro-González, Rafael, McKay, Christopher, Archer, P, Buch, Arnaud, Brunner, Anna, Coll, Patrice, Eigenbrode, Jennifer, Fairen, Alberto, Franz, Heather, Glavin, Daniel, Kashyap, Srishti, McAdam, Amy, Ming, Douglas, Steele, Andrew, Szopa, Cyril, Wray, James, Martín-Torres, F, Zorzano, Maria-Paz, Conrad, Pamela, and Mahaffy, Paul

Subjects
Curiosity, Mars, astrobiology, nitrates, nitrogen, Extraterrestrial Environment, Geologic Sediments, Mars, Nitrates, Nitric Oxide, Nitrogen, Temperature, Water, Wind
Abstract

The Sample Analysis at Mars (SAM) investigation on the Mars Science Laboratory (MSL) Curiosity rover has detected oxidized nitrogen-bearing compounds during pyrolysis of scooped aeolian sediments and drilled sedimentary deposits within Gale crater. Total N concentrations ranged from 20 to 250 nmol N per sample. After subtraction of known N sources in SAM, our results support the equivalent of 110-300 ppm of nitrate in the Rocknest (RN) aeolian samples, and 70-260 and 330-1,100 ppm nitrate in John Klein (JK) and Cumberland (CB) mudstone deposits, respectively. Discovery of indigenous martian nitrogen in Mars surface materials has important implications for habitability and, specifically, for the potential evolution of a nitrogen cycle at some point in martian history. The detection of nitrate in both wind-drifted fines (RN) and in mudstone (JK, CB) is likely a result of N2 fixation to nitrate generated by thermal shock from impact or volcanic plume lightning on ancient Mars. Fixed nitrogen could have facilitated the development of a primitive nitrogen cycle on the surface of ancient Mars, potentially providing a biochemically accessible source of nitrogen.

Published
2015

27. Background levels of methane in Mars’ atmosphere show strong seasonal variations

Author

Webster, Christopher R., Mahaffy, Paul R., Atreya, Sushil K., Moores, John E., Flesch, Gregory J., Malespin, Charles, McKay, Christopher P., Martinez, German, Smith, Christina L., Martin-Torres, Javier, Gomez-Elvira, Javier, Zorzano, Maria-Paz, Wong, Michael H., Trainer, Melissa G., Steele, Andrew, Archer, Doug, Sutter, Brad, Coll, Patrice J., Freissinet, Caroline, Meslin, Pierre-Yves, Gough, Raina V., House, Christopher H., Pavlov, Alexander, Eigenbrode, Jennifer L., Glavin, Daniel P., Pearson, John C., Keymeulen, Didier, Christensen, Lance E., Schwenzer, Susanne P., Navarro-Gonzalez, Rafael, Pla-García, Jorge, Rafkin, Scot C. R., Vicente-Retortillo, Álvaro, Kahanpää, Henrik, Viudez-Moreiras, Daniel, Smith, Michael D., Harri, Ari-Matti, Genzer, Maria, Hassler, Donald M., Lemmon, Mark, Crisp, Joy, Sander, Stanley P., Zurek, Richard W., and Vasavada, Ashwin R.

Published
2018

29. Red Dragon drill missions to Mars

Author

Heldmann, Jennifer L., Stoker, Carol R., Gonzales, Andrew, McKay, Christopher P., Davila, Alfonso, Glass, Brian J., Lemke, Larry L., Paulsen, Gale, Willson, David, and Zacny, Kris

Published
2017
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42. In Situ Real-Time Monitoring for Aseptic Drilling: Lessons Learned from the Atacama Rover Astrobiology Drilling Studies Contamination Control Strategy and Implementation and Application to the Icebreaker Mars Life Detection Mission

Author

National Aeronautics and Space Administration (US), Ministerio de Ciencia, Innovación y Universidades (España), Agencia Estatal de Investigación (España), Ministerio de Ciencia e Innovación (España), Bonaccorsi, Rosalba, Glass, Brian J., Moreno-Paz, Mercedes, García-Villadangos, Miriam, Warren-Rhodes, Kimberley, Parro-García, Víctor, Wilhite, Patrick, McKay, Christopher P., National Aeronautics and Space Administration (US), Ministerio de Ciencia, Innovación y Universidades (España), Agencia Estatal de Investigación (España), Ministerio de Ciencia e Innovación (España), Bonaccorsi, Rosalba, Glass, Brian J., Moreno-Paz, Mercedes, García-Villadangos, Miriam, Warren-Rhodes, Kimberley, Parro-García, Víctor, Wilhite, Patrick, and McKay, Christopher P.

Abstract

In 2019, the Atacama Rover Astrobiology Drilling Studies (ARADS) project field-tested an autonomous rover-mounted robotic drill prototype for a 6-Sol life detection mission to Mars (Icebreaker). ARADS drilled Mars-like materials in the Atacama Desert (Chile), one of the most life-diminished regions on Earth, where mitigating contamination transfer into life-detection instruments becomes critical. Our Contamination Control Strategy and Implementation (CCSI) for the Sample Handling and Transfer System (SHTS) hardware (drill, scoop and funnels) included out-of-simulation protocol testing (out-of-sim) for hardware decontamination and verification during the 6-Sol simulation (in-sim). The most effective five-step decontamination combined safer-to-use sterilants (3%_hydrogen-peroxide-activated 5%_sodium-hypochlorite), and in situ real-time verification by adenosine triphosphate (ATP) and Signs of Life Detector (SOLID) Fluorescence Immunoassay characterization of hardware bioburden and airborne contaminants. The 20- to 40-min protocol enabled a 4-log bioburden reduction down to <0.1 fmoles ATP detection limit (funnels and drill) to 0.2–0.7 fmoles (scoop) of total ATP. The (post-cleaning) hardware background was 0.3 to 1–2 attomoles ATP/cm2 (cleanliness benchmark background values) equivalent to ca. 1–10 colony forming unit (CFU)/cm2. Further, 60–100% of the in-sim hardware background was ≤3–4 bacterial cells/cm2, the threshold limit for Class <7 aseptic operations. Across the six Sols, the flux of airborne contaminants to the drill sites was ∼5 and ∼22 amoles ATP/(cm2·day), accounting for an unexpectedly high Fluorescence Intensity (FI) signal (FI: ∼6000) against aquatic cyanobacteria, but negligible anthropogenic contribution. The SOLID immunoassay also detected microorganisms from multiple habitats across the Atacama Desert (anoxic, alkaline/acidic microenvironments in halite fields, playas, and alluvial fans) in both airborne and post-cleaning hardware background. Final

Published
2023

43. Contribution of soil bacteria to the atmosphere across biomes

Author

Ministry of Education (Singapore), Archer, Stephen D. J., Lee, Kevin C., Caruso, Tancredi, Alcamí, Antonio, Araya, Jonathan G., Cary, S Craig, Cowan, Don A, Etchebehere, Claudia, Gantsetseg, Batdelger, Benito Gomez-Silva, Hartery, Sean, Hogg, Ian D, Kansour, Mayada K, Lawrence, Timothy, Lee, Charles K, Lee, Patrick K H, Leopold, Matthias, Leung, Marcus H Y, Maki, Teruya, McKay, Christopher P, Al Mailem, Dina M, Ramond, Jean-Baptiste, Rastrojo, Alberto, Šantl-Temkiv, Tina, Sun, Henry J, Tong, Xinzhao, Vandenbrink, Bryan, Warren-Rhodes, Kimberley A, B Pointing, Stephen, Ministry of Education (Singapore), Archer, Stephen D. J., Lee, Kevin C., Caruso, Tancredi, Alcamí, Antonio, Araya, Jonathan G., Cary, S Craig, Cowan, Don A, Etchebehere, Claudia, Gantsetseg, Batdelger, Benito Gomez-Silva, Hartery, Sean, Hogg, Ian D, Kansour, Mayada K, Lawrence, Timothy, Lee, Charles K, Lee, Patrick K H, Leopold, Matthias, Leung, Marcus H Y, Maki, Teruya, McKay, Christopher P, Al Mailem, Dina M, Ramond, Jean-Baptiste, Rastrojo, Alberto, Šantl-Temkiv, Tina, Sun, Henry J, Tong, Xinzhao, Vandenbrink, Bryan, Warren-Rhodes, Kimberley A, and B Pointing, Stephen

Published
2023

47. Evidence for indigenous nitrogen in sedimentary and aeolian deposits from the Curiosity rover investigations at Gale crater, Mars

Author

MSL Science Team, Stern, Jennifer C., Sutter, Brad, Freissinet, Caroline, Navarro-González, Rafael, McKay, Christopher P., Archer, P. Douglas, Buch, Arnaud, Brunner, Anna E., Coll, Patrice, Eigenbrode, Jennifer L., Fairen, Alberto G., Franz, Heather B., Glavin, Daniel P., Kashyap, Srishti, McAdam, Amy C., Ming, Douglas W., Steele, Andrew, Szopa, Cyril, Wray, James J., Martín-Torres, F. Javier, Zorzano, Maria-Paz, Conrad, Pamela G., and Mahaffy, Paul R.

Published
2015

48. Mars methane detection and variability at Gale crater

Author

the MSL Science Team, Webster, Christopher R., Mahaffy, Paul R., Atreya, Sushil K., Flesch, Gregory J., Mischna, Michael A., Meslin, Pierre-Yves, Farley, Kenneth A., Conrad, Pamela G., Christensen, Lance E., Pavlov, Alexander A., Martín-Torres, Javier, Zorzano, María-Paz, McConnochie, Timothy H., Owen, Tobias, Eigenbrode, Jennifer L., Glavin, Daniel P., Steele, Andrew, Malespin, Charles A., Archer, P. Douglas, Sutter, Brad, Coll, Patrice, Freissinet, Caroline, McKay, Christopher P., Moores, John E., Schwenzer, Susanne P., Bridges, John C., Navarro-Gonzalez, Rafael, Gellert, Ralf, and Lemmon, Mark T.

Published
2015

49. Oxychlorine Detection in Gale Crater, Mars and Implications for past Environmental Conditions

Author

Archer, P. Douglas, Jr, Ming, Douglas W, Sutter, Brad, Morris, Richard V, Clark, B. C, Mahaffy, P. R, Wray, J .J, Fairen, A .G, Gellert, Ralf, Yen, Albert, Blake, David F, Vaniman, David T, Glavin, Daniel P, Eigenbrode, Jen, Trainer, M .G, Navarro-González, Rafael, McKay, Christopher P, Freissinet, Caroline, and Martin, Peter

Subjects
Lunar And Planetary Science And Exploration
Abstract

The Sample Analysis at Mars (SAM) instrument on the Mars Science Laboratory (MSL) rover has detected oxychlorine compounds such as perchlorate or chlorate in Gale Crater samples. Two potential pathways for oxychlorine formation on Mars are UV-induced interaction between chlorine and metal oxides or atmospheric oxygen and radiolysis of Cl-containing surface materials by galactic cosmic rays, with the chlorine being volcanically derived in both cases. Oxychlorine compounds are identified by a diagnostic release of O2 at temperatures <600 °C and an HCl release from ~350-850 °C during sample pyrolysis. Of the 16 samples analyzed by SAM as of July 2018, 12 have contained oxychlorine compounds, including all four scooped samples and 8 of the 12 drilled samples.

Published
2018

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