Researchers from NASA’s Kennedy Space Center Air and Water Revitalization lab are studying two tanks, containing water with green dye, inside the Neil Armstrong Operations and Checkout Building in Florida on Nov. 13, 2019. The tanks have recently returned to Kennedy after remaining on the International Space Station for the past five years, originally sent to space to study slosh – the movement of water – in a zero-gravity environment to help engineers predict the movement of propellant in rocket tanks. With the slosh experiment now concluded, the tanks are being examined to determine if there is, or was, any microbial growth within them. The results will help NASA determine whether clean water can be stored in space for long-duration missions, an essential component to keeping astronauts safe and healthy as the agency prepares for missions to the Moon and beyond to Mars.