Kennedy Space Center’s Jason Fischer holds a sample of water in the Florida spaceport’s Neil Armstrong Operations and Checkout Building on Nov. 13, 2019. Two tanks of water have recently returned to Kennedy after spending the last five years on the International Space Station for an experiment to study slosh, or the movement of water, in a zero-gravity environment to help engineers predict the movement of propellant in rocket tanks. Kennedy’s Air and Water Revitalization lab is studying the water tanks 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.