An inspection of two faulty parts of the International Space Station today marked its 100th spacewalk, Space.com reports. Astronauts Peggy Whitson and Dan Tani, about to make the nearly seven-hour walk, were surprised to hear the news. "It is kind of mind boggling," Tani said. "I remember pre-ISS talking about the hundreds, and thinking that was a huge mountain to climb."
Whitson's walk marked another milestone, setting the record for most total ISS spacewalk time by a woman. She was already the station's first female commander when she arrived in October. In all, 73 astronauts and cosmonauts have spent more than 624 hours on ISS spacewalks over the past nine years. "That's an amazing record of resounding success," Tani said as he wrapped today's walk.