Pettit, NASA's oldest active astronaut, is celebrating his 70th birthday while landing in Kazakhstan after 220 days in space.

Learn more about who Suni Williams is and what her contributions have looked like throughout her career in space.

Astronaut Don Pettit shared what he calls “science of opportunity” to demonstrate how experimenting with our surroundings can ...

NASA astronaut Suni Williams works outside the International Space Station. Credit: NASA | edited by Space.com's Steve ...