Question:
Dafydd Rhys "Dave" Williams OC (born May 16, 1954) is a Canadian physician, public speaker and a retired CSA astronaut. Williams was a mission specialist on two space shuttle missions. His first spaceflight, STS-90 in 1998, was a 16-day mission aboard Space Shuttle Columbia dedicated to neuroscience research. His second flight, STS-118 in August 2007, was flown by Space Shuttle Endeavour to the International Space Station.
In January 1995, Williams was selected to join the 1995 international class of NASA mission specialist astronaut candidates. He reported to the Johnson Space Center in March 1995 and completed training and evaluation in May 1996. On completing basic training, he was assigned to work technical issues for the payloads/habitability branch of the astronaut office. From July 1998 to November 2002, Williams served as Director of the Space and Life Sciences directorate with responsibility for research in both physical and biomedical space sciences at the Johnson Space Center (JSC). With this appointment, he became the first non-American to hold a senior management position within NASA. Overall crew medical safety was one of his principal concerns, in addition to flight medical operations and JSC occupational and environmental health. His programs were directed toward protecting astronauts from the hazards of the space environment, including space radiation and microgravity, in addition to maintaining their medical, physical, and psychological well-being while aloft and on return to Earth. His other oversight responsibilities were in the fields of telemedicine, 3-D tissue culture/regeneration in microgravity, the curatorial management of extraterrestrial materials, and of qualifying humans for very long space journeys and ensuring their safe return to Earth. Williams served as an aquanaut on the first NEEMO (NASA Extreme Environment Mission Operations) crew aboard the Aquarius underwater laboratory in October 2001. During this mission, he was thrilled to shake hands underwater with Canadian underwater explorer Joe MacInnis. Williams was originally scheduled to command NEEMO 7 in October 2004, but was replaced by back-up crewmember and fellow CSA astronaut Robert Thirsk due to Williams undergoing review of a temporary medical issue. In April 2006, Williams commanded the NEEMO 9 mission. During this eighteen-day mission, the six-person crew developed lunar surface exploration procedures and telemedical technology applications.
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What caused him to join NASA?

Answer:
In January 1995, Williams was selected to join the 1995 international class of NASA mission specialist astronaut candidates.

Question:
William Miller Edwards (June 21, 1905 - June 12, 1987) was an American football player and coach. He served as the head football coach at Western Reserve University, Vanderbilt University and Wittenberg University in a career lasting more than 30 years, compiling a win-loss-tie record of 168-45-8. Edwards also coached the Detroit Lions of the National Football League (NFL) from 1941 to 1942, tallying a 4-9-1 record, and served as an assistant coach for the NFL's Cleveland Browns in the late 1940s. Raised near Massillon, Ohio, Edwards was the son of an immigrant from Wales who worked in the area's coal mines.
Having built a strong record at Western Reserve, Edwards was in the running for head coaching roles at a number of larger universities and professional teams. He met with officials at Marquette University and was considered a candidate for coaching duties at Colorado University and for the National Football League's Detroit Lions. After visiting with Lions owner Fred Mandel, Edwards ultimately was hired in February 1941 to succeed George Clark. Both Edwards and Dugan Miller signed two-year contracts. Edwards was given a $10,000 annual salary ($166,380 in 2017 dollars), more than double the $4,420 he was paid at Western Reserve. Edwards's stint as the Lions coach was unsuccessful. He guided the team to a 4-6-1 record in 1941, and Mandel fired him after three straight losses to begin the 1942 season as the team's roster was depleted by players' service in World War II. Detroit went on to lose all the rest of its games after John Karcis was named his replacement. Edwards enlisted in the U.S. Navy later in 1942 as America's involvement in the war intensified. While in the military, he served at St. Mary's Pre-Flight, a training program in California, and coached the Air Devils football team there. He also served at a base in Pensacola, Florida. Edwards was discharged in 1946, and spent a year in the sporting goods business in Cleveland, Ohio before reuniting with Brown, who had become the first coach of the Cleveland Browns in the All-America Football Conference (AAFC). Edwards took a position as a tackle coach and remained with the team for two seasons. He coached tackles including Ernie Blandin, Lou Rymkus and future Pro Football Hall of Fame member Lou Groza. The Browns won the AAFC championship in both of Edwards's years as an assistant; the team won all of its games in 1948, turning in professional football's first perfect season.
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What about his military service was he in a war?

Answer:
Edwards enlisted in the U.S. Navy later in 1942 as America's involvement in the war intensified.