As NASA continues to put forth efforts in seeking out life in the solar system with missions like Europa Clipper, Mars Sample Return, and Dragonfly, reducing the bioburden (number of living microbes) on spacecraft is required by NASA policy for the protection of potentially habitable worlds. In this project, we are testing the efficacy of a novel method for laser sterilization on stress tolerant bacterial spores (Bacillus subtilis) using a high energy femtosecond laser. To test the laser, we inoculate metal coupons with Bacillus subtilis spores. After laser treatment, we do a PVA (polyvinyl acetate) peel to recover the spores then we calculate to find the number of spores that survived the treatment. Our results show that within a certain pulse count range, increasing fluence increases sterilization effectiveness. We have demonstrated the ability to reduce viable microbial counts by at least 10-4. By studying laser sterilization, we could change the way spacecraft are sterilized by making the process more efficient and cost-effective.
Testing the Efficacy of Laser Sterilization as A Spacecraft Bioburden Reduction Alternative
STEM Better Together conference ; 2023 ; San Jose, CA, US
Conference paper
No indication
English
Airborne Endospore Bioburden as an Indicator of Spacecraft Cleanliness
SAE Technical Papers | 2006
|NTRS | 1966
|Engineering Index Backfile | 1962
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