In this Oct. 3, 2010 file photo, astronaut Scott Kelly crew member of the mission to the International Space Station, ISS, looks on in a museum at the Russian leased Baikonur cosmodrome, Kazakhstan. Scott and his twin Mark Kelly are taking part in an unprecedented study of identical twins looking into the effects of prolonged weightlessness. Mark will undergo tests on Earth while his brother Scott will embark on a one-year space station stint. (AP Photo/Dmitry Lovetsky, File)