We Remember John Glenn: 20 Photos of His Inspiring Patriotic Life

2. Glenn and six other military fliers were selected in 1959 to become the first American astronauts as part of Project Mercury. NASA put the “Mercury 7” through a grueling series of medical and psychological tests. Glenn is seen here being outfitted with a biosensor during astronaut training activities at Cape Canaveral, Fla., in 1961.

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