At even the minutest level, the space environment differs drastically from life on Earth. In addition to microorganisms that may already exist in space, crewmembers will bring bacteria, viruses, and other microscopic life forms with them from Earth. Once in space, these organisms may react in unexpected ways to the environmental conditions that exist in reduced gravity or in the closed environment of a spacecraft.
As a result, the microbiology of the space environment has long been a concern of the Human Research Program. HRP microbiologists study factors such as infectious diseases, antibiotic resistance, and metabolic and genetic changes. Future research will focus on the microbiological implications of long-term space travel and habitation, with the International Space Station serving as one of the primary sites for further study.