He has flown five space shuttle missions and made seven space walks between 1994 and 2007. His flights include the Endeavour mission in April 2001 to deliver the robotic arm Canadarm 2 to the International Space Station (ISS). Following the space shuttle Columbia disaster in 2003, Parazynski returned to space aboard space shuttle Discovery in October 2007; during that mission, Parazynski accumulated over 27 EVA hours in four space walks, including one unplanned one to fix damage to a live solar array on the ISS. He was selected as an astronaut in 1992 and retired from NASA in 2009. During his career he has logged over eight weeks in space, including 47 hours of space walks. He is also the only person to have both flown in space and climbed to the summit of Mount Everest. Parazynski has written a book with Susy Flory, titled The Sky Below.