Project Mercury
Project Mercury was the first manned space program of the United States. Operated by the civilian space agency NASA, it ran from 1958 to 1963. The program's goal was to send a Human into space and returned them safely to Earth. The program conducted twenty uncrewed flights and six successful crewed flights. Firsts in the program included the first American in space and the first American orbiting the Earth.
Costing $2.27 billion (when adjusted for inflation), this program was named after the god of communication from Roman mythology. The seven astronauts of this program were collectively named the Mercury Seven. Each one of them named their spacecraft ending with "7".
In 2024, at the gala for the Europa Mission astronauts, there was display about this project along with a replica of the Mercury capsule. (PIC: "Two of One")