NASA's "Hubble Repairman" John Grunsfeld, a former astronaut who was most well-known for his work repairing and upgrading the Hubble Space Telescope while it was in orbit, will be retiring from the world of space exploration with the agency on April 30.
Grunsfeld has headed NASA's Science Mission Directorate since 2012 and oversaw missions such as the Mars rover Curiosity's landing on the Red Planet and the New Horizons spacecraft's flyby of Pluto.
"After exploring strange new worlds and seeking out new life in the universe, I can now boldly go where I've rarely gone before - home," Grunsfeld said. "I'm grateful to have had this extraordinary opportunity to lead NASA science, and know that the agency is well-positioned to make the next giant leaps in exploration and discovery."
Throughout his career, Grunsfeld performed eight spacewalks in order to ensure the proper maintenance of the Hubble, conducting numerous upgrades and repairs on the observatory.
NASA almost abandoned the Hubble mission in favor of preparing to return humans to the moon, a move that left Grunsfeld devastated due to his passion for the Hubble Space Telescope mission, claiming that he was "willing to risk his life for it."
Despite numerous delays, the mission was eventually completed with the help of Grunsfeld, and the Hubble remains in use today.
"The only reason Hubble works is because we have a space shuttle," Grunsfeld said back in 2009. "And of all things we do, I think Hubble is probably the best thing we use it for."
"John leaves an extraordinary legacy of success that will forever remain a part of our nation's historic science and exploration achievements," said Charlie Bolden, NASA Administrator and former space shuttle commander.
"Widely known as the Hubble Repairman, it was an honor to serve with him in the astronaut corps and watch him lead NASA's science portfolio during a time of remarkable discovery," Bolden added. "These are discoveries that have rewritten science textbooks and inspired the next generation of space explorers."
Until NASA finds a suitable replacement for Bolden, Science Mission Directorate deputy chief Geoff Yoder will be acting administrator.
