The International Space Station has been colonized by thousands of microbe species, according to a new study in the journal PeerJ.
Quoting from the study, The Washington Post reported that the interior surfaces of the 17-year-old, 250-mile-high, airtight space station harbor at least 1,000 and perhaps more than 4,000 microbe species.
According to the report, David Coil, the co-author of the study, says that the finding is actually "reassuring" because it is probably a signature of a healthy spacecraft.
"Diversity is generally associated with a healthy ecosystem," David Coil said.
The samples for Coil's paper were collected in 2014 as part of the citizen science program Project MERCCURI which was conceived by a group of National Football League and National Basketball Association cheerleaders who are also scientists and engineers.
The samples were taken from 15 sites on the International Space station. These sites included the audio terminal unit microphone, air vents, the tab used to close the privacy panel on the crew sleep compartment. The microbe samples were packaged and flown to Earth, where the scientists at UC Davis sequenced their genomes.
The study revealed no "Andromeda Strains" that threaten the astronauts' well-being.
Interestingly, the International Space Station was dominated by human-associated microbes, particularly the kind that dwell on skin.