What project did an American aerospace engineer, test pilot, United States Air Force pilot, and one of the seven original astronauts, also referred to as the Original Seven or Astronaut Group 1, participate in?
Mercury Seven:  They are also referred to as the Original Seven or Astronaut Group 1. Gordon Cooper: Leroy Gordon "Gordo" Cooper Jr. (March 6, 1927 – October 4, 2004), (Col, USAF), better known as Gordon Cooper, was an American aerospace engineer, test pilot, United States Air Force pilot, and one of the seven original astronauts in Project Mercury, the first manned space program of the United States.
Project Mercury