Three scientific papers examined the risks involved in interplanetary exchange of micro-organisms that can cause difficulty for scientists to discern whether the life form in a planet is authentically produced or brought by explorers from other planets.
The researchers have pointed out the importance of knowing the Earth-born micro-organisms that can survive inside a spacecraft or in any landing vehicle since they can potentially contaminate other universal bodies such as Mars.
"If you are able to reduce the numbers to acceptable levels, a proxy for cleanliness, the assumption is that the life forms will not survive under harsh space conditions," said Kasthuri J. Venkateswaran, a researcher with the Biotechnology and Planetary Protection Group at NASA's Jet Propulsion Laboratory and a co-author on all three papers, in a press release.
However, a recently-done research shows that some microbes can be tougher than expected while some may employ various protective survival mechanisms during an interplanetary flight. Another finding also provided new insight on the survival capacities of robust microbial communities found in Earth's extremely hostile areas according to their responses on varying levels of radiation.
One particular area of concern is the spore-forming bacteria which are capable of tolerating some sterilization procedures and the harsh condition of outer space and other planetary surfaces. If the spores are protected against solar radiation because they are hidden in tiny pockets of the spacecraft or are found beneath the layer of other spores, they can survive the trip to Mars.
In one study, rock-colonizing cellular organisms are placed in the EuTEF facility for one and a half years. Researchers had based the study on '"ithopanspermia"-- a theory of the movement of organisms from one planet to the other. Though lithopanspermia needed many years to provide strong evidence of the organism's invincible feature, the results have somehow given an initial glimpse of their hard character in space. This further led to the possibility that space-bound rocks can actually carry life between planets.
The three papers, titled Survival of Bacillus Pumilus Spores for a Prolonged Period of Time in Real Space Conditions, Resistance of Bacterial Endospores to Outer Space for Planetary Protection Purposes, and Survival of Rock-Colonizing Organisms after 1.5 Years in Outer Space, were all published in the journal, Astrobiology.
