Grandpa to Break Scott Kelly's Space Record Jeff Williams will have spent 534 days in space by September By Arden Dier, Newser Staff Posted Mar 18, 2016 7:43 AM CDT 12 comments Comments NASA astronaut Jeff Williams in Kazakhstan on March 17. (AP Photo/Dmitry Lovetsky) (Newser) – It's a good thing Scott Kelly nabbed two records during his year in space because one will soon be broken. NASA astronaut Jeff Williams—who is rocketing into space on Friday with Russian cosmonauts Alexey Ovchinin and Oleg Skripochka—will become America's most experienced space traveler during a nearly six-month expedition on the International Space Station, reports Florida Today. At the end of Expedition 48, the 58-year-old will have spent 534 days in space over four trips to the ISS—14 days more than Kelly, who will retain his record for the longest single mission by an American at 340 days. "It's been a great privilege that I don't take for granted," says Williams, a grandfather who in 2010 became the first astronaut to interact live with NASA's social media fans from space, per ABC News. The Soyuz spacecraft departs from Kazakhstan at 5:26pm EDT and will dock at ISS six hours later. The three new arrivals will join America's Tim Kopra, British astronaut Tim Peake, and Russia's Yuri Malenchenko. Like Kelly, Williams will be a "guinea pig" for tests on space's effect on the human body. The 58-year-old Wisconsin native and retired Army colonel will also perform two spacewalks. He'll install a docking ring to be used by future Boeing and SpaceX crew capsules and activate an inflatable module, "a demonstration of expandable habitat technology that will be attached to the station for two years," per a press release. "Nothing becomes routine, nothing becomes boring up there," says Williams. Since his career has largely synced with the construction of the ISS (he first visited in 2000), he intends to use social media to share some of its history, per the Planetary Society.