National Aeronautics and Space Administration (NASA) boldly goes where no one has gone before. The federal agency's Aeronautics division conducts research on new flight technologies while its Exploration Systems works on human and robotic exploration and its Science unit studies climate, gravitation, and the atmosphere. The Space Operations division mans and maintains the International Space Station (ISS) in conjunction with several other nations; it also ran the space shuttle program until that was retired in 2011. NASA was founded in 1958, partly in response to Russia's launch of the Sputnik satellite, to research space and flight technology. It successfully landed two Americans on the moon in 1969.