Sunita Williams becomes the second astronaut to spend the longest time in space – see the astronauts who spent the most time aboard the ISS

NASA astronauts like Peggy Whitson, Sunita Williams, and Scott Kelly have set records for the longest space missions on the ISS, contributing significantly to research and exploration. Their extended stays in space have provided invaluable data on the effects of long-duration spaceflight, crucial for future missions to the Moon and Mars.