Chris Austin Hadfield (born August 29, 1959) is a Canadian retired astronaut, engineer, fighter pilot, and musician. The first Canadian to perform extravehicular activity in outer space, he has flown two Space Shuttle missions and also served as commander of the International Space Station (ISS). Prior to his career as an astronaut, he served in the Canadian Armed Forces for 25 years as an Air Command fighter pilot.

Hadfield has cited part of his career inspiration to have come to him as a child, when he watched the first crewed Moon landing by American spaceflight Apollo 11 on television. He attended high school in Oakville and Milton in southern Ontario, and earned his glider pilot licence as a member of the Royal Canadian Air Cadets. After enlisting in the Canadian Armed Forces, he earned an engineering degree at the Royal Military College in Kingston, Ontario. Hadfield learned to fly various types of aircraft in the military and eventually became a test pilot, flying several experimental planes. As part of an exchange program with the United States Navy and United States Air Force, he obtained a master's degree in aviation systems at the University of Tennessee Space Institute.

In 1992, Hadfield was accepted into the Canadian astronaut program by the Canadian Space Agency. He first flew in space in November 1995 as a mission specialist aboard STS-74, visiting the Russian space station Mir. He flew again in April 2001 on STS-100, when he visited the ISS and walked in space to help install Canadarm2. In December 2012, he flew for a third time aboard Soyuz TMA-07M to join Expedition 34 on the ISS. When Expedition 34 ended in March 2013, Hadfield became the commander of the ISS as part of Expedition 35, responsible for a crew of five astronauts and helping to run dozens of scientific experiments dealing with the impact of low gravity on human biology. During this mission, he chronicled life onboard the space station by taking pictures of Earth and posting them on various social media platforms. He was a guest on television news and talk shows and gained popularity by playing the ISS's guitar in space. Hadfield returned to Earth in May 2013, when the mission ended. He announced his retirement shortly after returning, capping a 35-year-long career as a military pilot and astronaut.