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Assessment of Gamma Radiation Resistance of Spores Isolated from the Spacecraft Assembly Facility During MSL AssemblySpore forming bacteria, a common inhabitant of spacecraft assembly facilities, are known to tolerate extreme environmental conditions such as radiation, desiccation, and high temperatures. Since the Viking era (early 1970's), spores have been utilized to assess the degree and level of microbiological contamination on spacecraft and their associated spacecraft assembly facilities. There is a growing concern that desiccation and extreme radiation resistant spore forming microorganisms associated with spacecraft surfaces can withstand space environmental conditions and subsequently proliferate on another solar body. Such forward contamination would certainly jeopardize future life detection or sample return technologies. It is important to recognize that different classes of organisms are critical while calculating the probability of contamination, and methods must be devised to estimate their abundances. Microorganisms can be categorized based on radiation sensitivity as Type A, B, C, and D. Type C represents spores resistant to radiation (10% or greater survival above 0.8 Mrad gamma radiation). To address these questions we have purified 96 spore formers, isolated during planetary protection efforts of Mars Science Laboratory assembly for gamma radiation resistance. The spores purified and stored will be used to generate data that can be used further to model and predict the probability of forward contamination.
Document ID
Document Type
External Source(s)
Chopra, Arsh (Pennsylvania State Univ. University Park, PA, United States)
Ramirez, Gustavo A. (California State Polytechnic Univ. Pomona, CA, United States)
Vaishampayan, Parag A. (Jet Propulsion Lab., California Inst. of Tech. Pasadena, CA, United States)
Venkateswaran, Kasthuri J. (Jet Propulsion Lab., California Inst. of Tech. Pasadena, CA, United States)
Date Acquired
April 21, 2015
Publication Date
August 1, 2011
Subject Category
Space Radiation
Distribution Limits
spacecraft assembly
gamma radiation