If you’ve clicked around the internets today, you might have come across a headline saying that the Russians have found alien bacteria clinging to the International Space Station (ISS).
The claim is based on an interview the Russian news agency TASS conducted with veteran cosmonaut Anton Shkaplerov released on Monday, which was later partially reprinted in English. During the interview, Shkaplerov explains that Russian cosmonauts have sampled the surface of the ISS 19 times, using cotton swabs to collect dust and debris from the station’s nooks and crannies, bringing the samples back to Earth to be tested.
"And now it turns out that somehow these swabs reveal bacteria that were absent during the launch of the ISS module," says Shkaplerov. "That is, they have come from outer space and settled along the external surface. They are being studied so far and it seems that they pose no danger."
In other words, the ISS modules were clean and sterile when they launched in the late 1990s and early 2000s. But now researchers are finding parts that are contaminated with bacteria and other crud. So does that mean the microbes on the station are micro-E.T.’s? It is possible—and it’s hard to truly assess what the Russians have found from one vague, translated statement—but it's unlikely.
As Jason Le Miere reports for Newsweek, Shkaplerov is likely referring to a Russian program starting in 2010 called "Test," in which cosmonauts swabbed the station. The idea is that the space station could act as a de facto space-debris sponge, passively collecting the bits and pieces that float past Earth, since according to TASS, the ISS spends 60 percent of its time in the dust fields of comets.
“The micrometeorites and comet dust that settle on the ISS surface may contain biogenic substance of extra-terrestrial origin in its natural form,” the Russian space agency Roscosmos tells TASS. “The ISS surface is possibly a unique and easily available collector and keeper of comet substance and, possibly, of biomaterial of extra-terrestrial origin.”
Even if the ISS exterior is hosting bacteria, it doesn’t mean it comes from the Great Beyond. Back in 2010, bacteria collected from rocks near the village of Beer in Great Britain were exposed to the elements on the exterior of the ISS for 553 days. One batch of the bugs survived the constant cosmic radiation, UV light and 300 degree temperature swings, meaning there are terrestrial bacteria that can make it in the harshness of space.
In fact, despite an obsession with decontamination and keeping everything that goes to the ISS bug-free, a 2015 study showed that the interior of the cosmic complex is swarming with microbes. Sequencing the DNA found in the dust from one of the ISS’s air filters, researchers detected over two dozen genera of bacteria and fungus—two of these could contain potentially harmful pathogens.
It’s also possible that bacteria from Earth can make it to space on their own. According to a 2013 study, researchers found living microbes in samples collected five to ten miles above the Gulf of Mexico and Caribbean Sea during hurricane season.
As Miriam Kramer reported for Space.com in 2014, other microbes, like tardigrades or water bears, are known to be capable of tolerating the harshness of space. “Note that there is a long history of U.S. and European missions proving that microbes could survive in low Earth orbit for extended periods of time,” NASA astrobiologist Lynn Rothschild told Kramer.
This isn’t the first time that TASS has reported a strange find at the ISS. Kramer's article was focused on the 2014 claim from space station official Vladimir Solovyov who said that the cosmonauts had found sea plankton on the exterior of the space station, surmising that it was blown up there by air currents.
NASA was not able to confirm the claims at the time. But earlier this year, TASS offered more details on the find:
“Experiments of various years have revealed fragments of Mycobacteria DNA — a marker of heterotrophic bacterial sea plankton in the Barents Sea; the DNA of extremophile bacteria of the genius Delftria; the DNA of bacteria closely related to those found in soil samples from the island of Madagascar; vegetative genomes; the DNA of certain species of Archaea and the DNA of fungus species Erythrobasidium and Cystobasidium.”
If confirmed, that would mean the biosphere extends quite a bit farther into space than previously thought. Which would be awesome, but we’ll need to see some peer-reviewed research before we can vouch for the space plankton—or, for that matter, the latest "alien" bacteria.