Christopher Williams (astronaut)

Christopher Williams
Williams in February 2024
Born
Christopher Leigh Williams

(1983-10-23) October 23, 1983
New York City, New York, U.S.
Education
FamilyJuan Williams (uncle)
Space career
NASA astronaut
Time in space
110 days, 12 hours, 51 minutes
(currently in space)
SelectionNASA Group 23 (2021)
MissionsSoyuz MS-28 (Expedition 73/74)
Mission insignia
Scientific career
FieldsPhysics
ThesisInitial Exploration of 21-cm Cosmology with Imaging and Power Spectra from the Murchison Widefield Array (2012)
Doctoral advisorJacqueline Hewitt

Christopher Leigh Williams is an American medical physicist and NASA astronaut. Selected in 2021, Williams is currently on his first mission aboard Soyuz MS-28 in November 2025, serving as a flight engineer and member of Expedition 73/74 on the International Space Station. He is expected to spend approximately eight months aboard the station, contributing to various scientific investigations and technology demonstrations. Before joining NASA, Williams worked at Harvard Medical School, Brigham and Women's Hospital, and the Dana–Farber Cancer Institute, where he led efforts in MRI-guided radiation therapy for cancer treatment. He holds a Ph.D. in physics from the Massachusetts Institute of Technology and is board-certified in medical physics.