Thursday, August 15, 2019

Testing Technology for NASA

Astrobiology Science and Technology for Exploring Planets (ASTEP) Project
By the 2006 expedition, the priority for AMASE trips shifted towards testing new instruments in the field prior to their being selected for space flight on upcoming Mars missions. In a proposal to the Astrobiology Science and Technology for Exploring Planets (ASTEP) program, we asked the following questions:
1) How do we access suitable samples?
2) How do we identify, sample and detect molecules of interest at suitable spatial and detection sensitivity scales?
3) How do we ensure sample integrity and control for cross contamination by organic, biogenic and inorganic molecules?
4) How do measurements from laboratory and field instrumentation compare in terms of analyzing terrestrial samples from a Mars relevant environment?

         Each year we worked with a JPL crew that brought along a sophisticated rover
Cliffbot rover in Svalbard
 that was put to the test on slopes and terrains similar to those found on Mars. JPL scientists Terry Huntsberger, Ashely Stroupe, Paulo Younse, and Michael Garrett took turns operating the Cliff-Bot rover. This team was given 2-3 days of special time to test their rover. Many of us envisioned the rover swiftly covering the landscape in a matter of minutes, reaching out its robotic arm, scooping up sediment and returning faithfully to its base. Unfortunately, sending a rover over a complex landscape, as though it were on a remote planetary body, was a much slower, hour-by-hour and inch-by-inch process that tested the patience of many a crewmember.
         The project now included two instruments that were ultimately chosen to fly on Mars Curiosity: CheMin and SAM (Sample Analysis on Mars). CheMin’s instrument PI is David Blake, a scientist at NASA Ames. Blake, a US Navy veteran and an expert in designing and testing field X-ray mineralogy instruments, is also quite a character. Dave sang navy songs laced with profanity, told jokes and funny stories of all types, and laughed with a distinct pirate-like “Har har”. To say he brought some “color” to the expeditions is an understatement. SAM’s PI, Paul Mahaffey, brought a crew of scientists from NASA Goddard including Pamela Conrad, Jennifer Eigenbrode, and Inge Loes ten Kate. SAM is a combination gas chromatograph-mass spectrometer (GC-MS) equipped with the capability of high temperature pyrolysis GC-MS and a tunable diode laser for measuring methane and its isotopic composition. CheMin was fully portable and field deployable; SAM was not.
Mission "manager" Steve Squyres
         In addition to instrument teams, Steven Squyres, the PI of the Mars Exploration Rover mission with Opportunity and Spirit, was invited to observe sampling in the field and to conduct mock Mars sampling exercises (Science Operations Working Group: SOWG--pronounced “Sahg”) based on his experience “roving Mars” from Earth. Squyres was our most “famous” AMASE participant. We were a bit in awe to first meet him, but he quickly adapted to the informal, give-and-take atmosphere of discovery that was AMASE. Steve is a rail thin guy who likes to climb ice mountains in winter and must have the metabolism of a bird. Dressed in black track jacket and jeans with his head wrapped in a red printed bandana, Squyres led the SWOG sessions seriously. He also had the chance to participate in active fieldwork, where he was often a fish out of water so to speak, since he is a space and planetary scientist with little training in biology.  He particularly enjoyed helping out Verena Starke with her work and sampling at Troll Springs.
Paul Mahaffey and his SAM prototype
         The SWOG exercises were designed so that scientists and engineers, required to work together in teams during real missions, would learn as a group how to answer the four technical questions posed above. The question of how to access suitable samples had to be tackled separately with specialized practice with the rover team. Our second question--how to identify, sample and detect molecules of interest at suitable spatial and detection sensitivity scales?-- took up most of our time.
         For many of the last AMASE expeditions, about three SOWG exercises were held each year. Traveling with AMASE was a German camera crew led by Nicole Schmitz, who was testing a camera that she hoped would fly on a future Mars mission. She joined AMASE expedition photographer Kjell Ove Storvik, Steele, and Amundsen, who chose an outcrop for investigation.  The two photographers then provided PanCam like photos that were sent back to the team “on Earth”--meaning inside a room on the ship--for them to analyze. Photos were in black and white and then pieced together to form a mosaic of the outcrop. The CheMin, SAM, UV fluorescence, and Life Marker Chip instrument teams were assigned an energy budget. For each measurement requested, the team needed to use up one or more of its energy allotments to “pay” for the analyses.
Pan Conrad and Dave Blake with his CheMin
         After the teams finished arguing about where on the outcrop the samples should be taken and how they would use their precious energy resources, the crew on land sampled the outcrop with hammers and delivered the samples to the instruments. CheMin, UV fluorescence, and the Life Marker Chip instruments were deployed in the field; SAM on board ship. When the analyses were completed, data were “downlinked” from “Mars” to “Earth” for inspection and analysis. At this point, teams argued as to whether they were able to detect molecules of life on “Mars”. The discussion then shifted to whether or not a sample should be cached for future return to Earth for more sophisticated sampling.
         These exercises were intense: periods of high drama and discussion, followed by periods of restless inactivity, cooped up on the ship or lounging on a rock outcrop. All samples were brought back to the ship and analyzed by the full AMASE crew with a summary report for each SOWG exercise. As ASTEP funding and matching European Space Agency funding neared completion in 2010, AMASE entered a period of uncertainty in particular about its focus on discovery-based science versus technology testing. Folks like Blake and Mahaffey needed to turn their attention completely to Mars Science Laboratory. The yearly, international expeditions with Hans, ESA and NASA collaborators, and Carnegie scientists ended on the flat side.

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