‘Bacillus pumilus SAFR-032’ Bacteria from Earth may contaminate Mars; confuse researchers in future about origin of life on Mars: NASA
NASA has expressed concerns about possible contamination of the Martian surface due colonization of micro-organisms riding with the space-crafts sent from Earth. These bacteria could contaminate celestial bodies such as Mars, making it difficult for researchers to ascertain if a life form actually originated on the site.
Currently, spacecraft landing on Mars or other planets where life might exist must meet requirements for a maximum allowable level of microbial life, or bioburden. Recent study has shown that some microbes are tougher than expected and may use various protective mechanisms to survive interplanetary flights.
For example, spores of Bacillus pumilus SAFR-032 have shown particularly high resistance to techniques such Ultra-Violet (UV) radiation and peroxide treatment used to clean spacecraft. These spores were exposed for 18 months on the European Technology Exposure Facility (EuTEF), a test facility mounted outside the ISS. Surprisingly, some of the spores pulled through for 18 months.