|Manu||Date: Saturday, 14-November-2020, 11:36 AM | Message # 1|
|A year in space is no walk in the park. Just ask Scott Kelly, the American astronaut who spent a year on the International Space Station (ISS) in 2015.|
His long-term stay in space changed his DNA, telomeres, and gut microbiome, he lost bone density, and he still had sore feet three months later.
But it's a whole other thing to survive in the naked space outside the protection of the ISS, where UV radiation, vacuum, huge temperature fluctuations, and microgravity are all imminent threats.
So, it's quite a feat that a species of bacterium first found in a can of meat, Deinococcus radiodurans, was still alive and kicking after a year spent living on a specially designed platform outside the pressurized module of the ISS.
Researchers have been investigating these mighty microbes for a while; back in 2015, an international team set up the Tanpopo mission on the outside of the Japanese Experimental Module Kibo, to put hardy bacterial species to the test.
Now, D. radiodurans has passed with flying colors.
The bacterial cells were dehydrated, shipped to the ISS, and placed in the Exposed Facility, a platform continuously exposed to the space environment; in this case, the cells were behind a glass window that blocked out UV light at wavelengths lower than 190 nanometers.
"Results presented in this study may increase awareness regarding planetary protection concerns on, for instance, the Martian atmosphere which absorbs UV radiation below 190-200 nm," the team from Austria, Japan, and Germany wrote in their new paper.
"To mimic this condition, our experimental setup on the ISS included a silicon dioxide glass window."
This isn't the longest time D. radiodurans has been kept in these conditions – back in August we wrote about a sample of the bacterium being left up there for three whole years.
But the team weren't trying for a world record, instead they were trying to uncover what makes D. radiodurans just so good at surviving in these extreme conditions.
Read more/full article/source - https://www.livescience.com/bacteri....on.html