Project Mercury was the first human spaceflight program of the United States and ran from 1959 through 1963 at a cost of $384 million dollars.
Four of the Project Mercury spaceflights included monkeys, or non-human primates.
Sam, a Rhesus macaque, was launched on 4 December 1959 on Little Joe 2 to 85 km altitude.
Miss Sam, a Rhesus macaque, was launched on 21 January 1960 on Little Joe 1B to 15 km altitude.
In January 1961, the first Mercury was tested with a chimpanzee named Ham in a successful suborbital flight.
Enos, a chimpanzee, was launched on 29 November 1961 on Mercury-Atlas 5 for a 2-orbit flight.
Several months later, astronaut Alan B. Shepard also survived a successful suborbital flight.