But to make these big missions happen, researchers are thinking small. So small, in fact, that they're focusing on the microscopic bacteria in our guts.
This is because keeping humans alive and healthy on years-long missions is a major challenge, complicated by the unknown effects of microgravity on various nasty bugs that make humans sick. At least one common pathogen, Salmonella, gets more virulent in space, and microgravity alters the activity of other microbes as well.
What that means for astronauts is yet unknown, but ongoing experiments — including one that flew on a recent shuttle mission that looked at the gut bacteria of squid — aim to find out.
"We're very concerned with the potential of increased infectious disease," on long-duration missions, said Cheryl Nickerson, a professor in the Center for Infectious Disease and Vaccinology at The Biodesign Institute at Arizona State University, who studies the effect of spaceflight on microbes. "They're living, if you will, in a tin can. It's a closed environmental system … It becomes very important for us to understand the microflora in our bodies, both the good and the bad ones."



