Mark Kelly

Mark Kelly was born in 1964 in Orange, New Jersey, the identical twin of astronaut Scott Kelly, and grew up in a family of police officers. He earned a bachelor's degree in marine engineering and nautical science from the U.S. Merchant Marine Academy and a master's in aeronautical engineering from the U.S. Naval Postgraduate School, then became a U.S. Navy combat aviator, flying 39 missions in F/A-18 Hornets during Operation Desert Storm before serving as a test pilot. NASA selected him as an astronaut in 1996, alongside his brother — a first for the astronaut corps.

Kelly flew four Space Shuttle missions, all in support of building and supplying the International Space Station. He piloted STS-108 aboard Endeavour in 2001, a crew-rotation and logistics flight, and piloted STS-121 aboard Discovery in 2006, a critical return-to-flight test mission following the Columbia accident. He then commanded two flights: STS-124 aboard Discovery in 2008, which delivered the pressurized core of Japan's Kibo laboratory to the station, and STS-134 aboard Endeavour in 2011, the final flight of that orbiter, which carried the Alpha Magnetic Spectrometer (AMS-02) to the ISS. He commanded STS-134 just months after his wife, U.S. Representative Gabby Giffords, was gravely wounded in the January 2011 Tucson shooting — a convergence of personal and public events that drew national attention to the mission.

After retiring from NASA and the Navy, Kelly co-founded the gun-violence-prevention organization Giffords with his wife and became a prominent advocate on the issue. In 2020 he was elected as a Democratic U.S. Senator from Arizona, bringing his engineering and spaceflight background to debates over space policy, veterans' affairs, and technology. Alongside his brother Scott, he formed one of the most unusual pairs in spaceflight history — two identical twins who both reached orbit and together became the natural subjects of NASA's Twins Study of long-duration spaceflight. His public life reflects a maxim he often repeats: courage is not the absence of fear, but the willingness to act in spite of it.