Mid-March, NASA investigators announced that they had found an unknown life form hiding aboard the International Space Station. And they were cool with that.
In fact, for an organization known for cutting-edge public communications strategy – Mars rovers don’t write their own tweets, is what I’m saying – everyone has been pretty quiet about this discovery.
Almost to quiet.
It is true that the new life was not, for example, a xenomorphic alien with acid as blood. It was a new bacterial species, unknown on Earth, but whose genes identified it as coming from a well-known terrestrial lineage called MethylobacteriumMost of the time, its members hang to hang between the roots of plants, not on the walls of space stations. Still, you’d think that a probably-not-but-maybe-evolved microbe in space would deserve a little more crazy. But here we are. No one was really surprised – and the reasons why could determine the future of human space exploration.
As part of an ongoing research project into the microbial life of the ISS, astronauts on board in 2015 and 2016 wiped down various areas of the station and sent home the wipes they used. Over the following years here on Earth, a team of researchers headquartered at the Jet Propulsion Laboratory’s Biotechnology and Planetary Protection Group isolated the microbes and sequenced their genes. One species, found on a HEPA filter in the station’s life support system, was a garden variety (literally!) Methylobacterium rhodesianumBut three samples – from a surface near the materials research rack, a wall near the “dome” of windows, and the astronauts’ dining table – were something new. The researchers who ran the project called it M. ajmalii
It wasn’t even the first time these researchers had found a new bacteria in space. They had already found a whole different unknown bacteria in that set of ISS samples – they published a paper on that in 2017. There is a chance that these bugs are, in a sense, aliens, that they evolved on the station. But it is a thin one. Chances are they were hitchhiking on cargo or on astronauts, and the microbe hunters only noticed them because they went to see. “There are undoubtedly opportunities for evolution in space, but the space station is so young. He is only 20 years old. Bacteria may not have evolved in that time, ”said Kasthuri Venkateswaran, the JPL microbiologist who leads the project.
Perhaps more interesting is to find out which bacteria are zeros on Earth, but heroes in the lofty, closed environment of a spaceship. Therefore, studying the International Space Station’s microbiome – the bacteria, fungi and viruses that thrive on board – could be critical to the safety of missions to Mars or permanent bases on other worlds. As on Earth, human health in space depends in part on a healthy microbiome and a good relationship with the microbiome of the vessel or shelter. “We can say that new species transported by the crew have a number of characteristics to withstand the conditions there,” says Venkateswaran. The rest may have died. These are the things that survive. “
Space is real quite unpleasant. Outside of a barrel or vacuum pack, it would be a race to see if you died first from asphyxiation or lyophilization. (The high levels of harsh radiation are more of a long-term deal breaker.)
So the inside of those barrels and packs must be closed systems. The only things that come and go are cargo and astronauts. But wherever people go, they bring their ride-on microbes with them – in their guts, on their skin, in their noses and mouths. That’s true in your home, and it’s true on the ISS. But the ISS isn’t like your home, and not just because it recycles air and water, and you can’t open the windows. The air in the ISS is drier, with more carbon dioxide. The radiation levels are higher. There is no gravity. (“We are used to certain types of microbes staying on the floor, but they don’t stay on the floor if there is no floor,” said John Rummel, a former NASA Planetary Protection Officer responsible for keeping aliens away from Earth. and life on Earth from other places.) It doesn’t smell that fresh inside the ISS, and because it’s full of nooks and crannies for water droplets to float in and then attach, thanks to its surface tension, it has lots of places where microbes can can hang out.