NASA makes us proud to be Americans. And even more so, the agency is an engine of discovery and innovation that benefits all ...

Mark and Scott Kelly, twin brothers and former NASA astronauts, spoke to "CBS Mornings" about how the agency is set to lose ...

Identical twins Mark Kelly, left, and brother Scott, right, are veterans of multiple spaceflights. Scott Kelly lived aboard the International Space Station for 340 days in 2015-16. NASA ...

Mark Kelly wrote that his parents also taught him and demonstrated for him the importance of a strong work ethic. His father told the boys they could join the welders' union, he had a contact there.

NASA Administrator Bill Nelson also attended Mark Kelly's induction ceremony. He was raised in Malabar, graduated from Melbourne High, represented the Space Coast in Congress, and flew aboard ...

Before Mark Kelly emerged as one of the lead contenders for VP on the Democratic ticket, the former astronaut earned more than a million dollars on the speaking circuit.

Mark Kelly's four years in the Senate came after a career in the military, at NASA and on front lines of advocacy for gun ...

In February, former NASA astronaut Mark Kelly announced his decision to run for the US Senate in Arizona — a move that he had been thinking about for the last couple of months. We spoke with ...

Kelly has an identical twin, Scott Kelly, who was also a NASA astronaut. From 2015 to 2016, Scott spent nearly a year aboard the International Space Station, while Mark stayed on the ground.

Kelly says his twin brother, Scott Kelly, who just returned to Earth after 340 days in space, was temporarily 2 inches taller. NASA is studying the pair to explore what spaceflight does to the body.

But Kelly won’t be alone. He’ll be joined by his identical twin, retired NASA astronaut Mark Kelly. The pair have been participating in what might be the most far-out twin study ever conducted.

June 21, 2011 -- Mark Kelly, the astronaut husband of Rep. Gabrielle Giffords, announced today he is retiring from NASA to spend time with his wife and write a memoir with her.