Chris Cassidy
Official portrait, 2020
Born	Christopher John Cassidy (1970-01-04) January 4, 1970 (age 54) Salem, Massachusetts, U.S.
Education	United States Naval Academy (BS) Massachusetts Institute of Technology (MS)
Spouse	Peggy Yancer[1]
Space career
NASA astronaut
Rank	Captain, USN
Time in space	377d 17h 49m
Selection	NASA Group 19 (2004)
Total EVAs	10
Total EVA time	54h 51m
Missions	STS-127 Soyuz TMA-08M (Expedition 35/36) Soyuz MS-16 (Expedition 62/63)
Mission insignia
Retirement	May 28, 2021

Christopher John "Chris" Cassidy (born January 4, 1970) is a retired NASA astronaut and United States Navy SEAL. Chris Cassidy achieved the rank of captain in the U.S. Navy. His first spaceflight was on a Space Shuttle mission in 2009. He was the Chief of the Astronaut Office at NASA from July 2015 until June 2017.

Cassidy was born in Salem, Massachusetts on January 4, 1970. He attended York High School, in York, Maine.^[2] He then graduated from the Naval Academy Preparatory School in Newport, Rhode Island, in 1989. He received a Bachelor of Science degree in mathematics at the United States Naval Academy in 1993 and a Master of Science degree in ocean engineering at the Massachusetts Institute of Technology in 2000.

Cassidy graduated from BUD/S class 192 in 1993 as Honor man. He served for ten years as a member of the Navy SEALs. His specializations in military tactics include long range special reconnaissance (vehicular and foot patrols), direct action building assaults, non-compliant ship-boardings, desert reconnaissance patrols, combat diving, underwater explosives, and a variety of air operations, including parachuting, fast roping, and rappelling. He made four six-month deployments: two to Afghanistan, and two to the Mediterranean Sea. Cassidy served as Executive Officer and Operations Officer of Special Boat Team 20 in Norfolk, Virginia, and SEAL Platoon Commander at SEAL Team 3 in Coronado, California. He deployed to the Afghanistan region two weeks after the September 11 attacks. He served as Ground Assault Force Commander for international and U.S.-only combat missions in Afghanistan. Cassidy led two months of non-compliant ship-boardings in the Northern Persian Gulf. Cassidy was also a SEAL Delivery Vehicle (SDV) platoon commander at SEAL Delivery Vehicle Team Two in Norfolk. He accumulated over 200 hours underwater as pilot, navigator, or mission commander of a two-man flooded submersible SDV, which is launched and recovered from a host-ship submarine. He also served as drydeck shelter platoon commander at SEAL Delivery Vehicle Team Two in Norfolk. Cassidy volunteered for and completed a week-long, 180-mile (290 km) charity kayak paddle from Norfolk, Virginia to Washington, D.C. to raise money and awareness for the Special Operations Warrior Foundation.^[2]

Cassidy was selected as an astronaut candidate by NASA in May 2004. In February 2006 he completed Astronaut Candidate Training, which included scientific and technical briefings, intensive instruction in Space Shuttle and International Space Station systems, physiological training, T-38 Talon flight training, and water and wilderness survival training. Completion of this initial training qualified him for various technical assignments within the Astronaut Office and future flight assignment as a mission specialist.^[2]

In February 2008, Cassidy was assigned to his first spaceflight as a mission specialist on STS-127, a Space Shuttle mission to deliver the Exposed Facility of the Japanese Experiment Module (JEM-EF) to the ISS aboard Space Shuttle Endeavour.^[3]

Cassidy and his six fellow crew members lifted off aboard Endeavour from the Kennedy Space Center on July 15, 2009.^[4] The seven astronauts docked with the ISS on July 17, joining the six-person Expedition 20 crew commanded by Russian cosmonaut Gennady Padalka. This marked the first time that 13 people had been in space together, a record that has not been surpassed since.^[5] On July 22, 2009, Cassidy stepped outside the ISS with NASA astronaut David Wolf for his first spacewalk. The two began work replacing batteries on the P6 Truss and continued work on installing the JEM-EF. The EVA was called off after 5 hours and 59 minutes for excess carbon dioxide in Cassidy's suit.^[6]

Over the course of STS-127, Cassidy participated in two more spacewalks with NASA astronaut Thomas Marshburn. The two completed replacing the batteries on the P6 truss and completed the installation of the JEM-EF during two excursions lasting 7 hours and 12 minutes and 4 hours and 57 minutes, respectively.^[7] Cassidy's third spacewalk marked the completion of the Japanese Experiment Module, a feat that took three space shuttle missions starting with STS-123.

On July 31, 2009, Cassidy returned to the KSC Shuttle Landing Facility, wrapping up his first spaceflight after 15 days in space.^[8]

Cassidy was assigned to the Expedition 35 crew as a flight engineer and flew to the ISS aboard Soyuz TMA-08M (US designation: 34S), which launched on March 28, 2013.^[2][9] On May 11, 2013, Cassidy and Thomas Marshburn performed an unplanned spacewalk to replace a pump controller box suspected to be the source of an ammonia coolant leak.^[10][11]

Cassidy participated in two US spacewalks from the ISS in June/July 2013.^[9] On July 16, 2013, he was joined by Luca Parmitano on a spacewalk. The EVA was cut short when Parmitano reported water floating behind his head inside his helmet.^[12] During the EVA, Cassidy took his space selfie. That photo became one of the best selfies of 2013 listed by many news sites.^[13][14]

Cassidy was named Chief of the Astronaut Office at NASA in July 2015, succeeding Bob Behnken.^[15]

On June 2, 2017, Cassidy was replaced by Patrick G. Forrester as Chief of the Astronaut Office and was returned to normal flight status.

Cassidy launched onboard Soyuz MS-16 on April 9, 2020, as part of Expedition 62. He was the ISS commander for Expedition 63, which consisted of Cassidy and Russian cosmonauts Ivan Vagner and Anatoli Ivanishin.^[16][17] Cassidy was joined by fellow NASA astronauts Doug Hurley and Bob Behnken on May 31, 2020, with the docking of Crew Dragon Demo-2. Cassidy and his crew returned to Earth on October 21, 2020. They landed in Dzhezkazgan, Kazakhstan at 10:54 pm.

Cassidy's last two years as an astronaut were the central feature of the Disney+ docuseries Among the Stars. The series was removed from Disney+ on May 26, 2023, amidst the Disney+ and Hulu purge.^[18]

Cassidy joined the National Medal of Honor Museum Foundation as President and CEO in August 2021^[19] after retiring from the Navy and the NASA Astronaut Corps earlier that year. Since his retirement from government service, Cassidy has also been active on the boards of directors for several non-profits, including the Navy SEAL Foundation^[20] and the John F. Kennedy Library Foundation.^[21] He also serves as an advisor for New Vista Acquisition Corp,^[22] a Special Purpose Acquisition Company (SPAC).

Cassidy was awarded the Bronze Star with "V" device and the Presidential Unit Citation for leading a nine-day operation at the Zhawar Kili cave complex, a national priority objective directly on the Afghan–Pakistan border, during Operation Enduring Freedom. Cassidy was a guest speaker at the USNA Combat Leadership Seminars in 2003 and 2004. He was awarded a second Bronze Star for combat leadership service in 2004 during Operation Enduring Freedom in Afghanistan.^[2]

Chris Cassidy is also the 500th person in space. He achieved this when his crewmates so designated him during the STS-127 mission.^[23] He is also the second SEAL to fly in space, following William Shepherd, a veteran of four missions.

	Bronze Star with valor device and award star
	Combat Action Ribbon
	Presidential Unit Citation
	NASA Exceptional Achievement Medal
	NASA Space Flight Medal
	National Defense Service Medal with service star
	Armed Forces Expeditionary Medal
	Afghanistan Campaign Medal
	Global War on Terrorism Expeditionary Medal
	Sea Service Deployment Ribbon

Cassidy is married to the former Peggy Yancer from Elyria, Ohio. They have five children between the two of them. Recreational interests include traveling, biking, camping, snow skiing, weight lifting, running, basketball, real estate, and home improvement.^[1]

Cassidy is a licensed amateur radio operator (ham), holding U.S. Technician level license KF5KDR.^[24] Cassidy has participated in several Amateur Radio on the International Space Station events with students in the United States.

Cassidy announced his retirement from both the Navy and NASA Astronaut Corps on May 28, 2021.

 This article incorporates public domain material from websites or documents of the National Aeronautics and Space Administration.

• NASA biography Archived May 14, 2021, at the Wayback Machine
• Spacefacts biography of Christopher Cassidy