Endeavour commander Mark Kelly quits NASA

Mark Kelly, the veteran combat pilot and astronaut, has announced he's retiring from the US Navy and quitting NASA on 1 October.

In an announcement on his Facebook page, Kelly admits it was "not an easy decision" to move on from a career which has encompassed Desert Storm combat missions and four space shuttle trips to the International Space Station.

Kelly was the commander of Endeavour on its last mission - STS-134 to the ISS - while his wife, Arizona congresswoman Gabrielle Giffords, was recovering from the headshot she received in the Tucson shooting in January.

During that trip, commander Kelly took a moment to record a message for the crowd at a U2 gig at Quest Field, Seattle:

Back down at Facebook, Kelly says: "As life takes unexpected turns we frequently come to a crossroads. I am at this point today.

"Gabrielle is working hard every day on her mission of recovery. I want to be by her side. Stepping aside from my work in the Navy and at NASA will allow me to be with her and with my two daughters. I love them all very much and there is no doubt that we will move forward together. After some time off, I will look at new opportunities and am hopeful that one day I will again serve our country."

Whatever the future holds for Kelly, he's certain that NASA will continue on the right track without him. He insists: "I know that as our space program evolves, there are those who will question NASA's future. I am not among them. There isn't a group more dedicated to its mission or more capable than the outstanding men and women of NASA.

"Exploration is a critical component of what makes our country great. We will continue to explore and NASA will continue to lead that effort." ®