The first woman to ever enter space was Valentina Tereshkova. She flew in 1963, but it was not until the 1980s that another woman entered space again. At the time, all astronauts were required to be military test pilots; and women were not able to enter this career, which is one reason for the delay in allowing women to join space crews. After the rules were changed, Svetlana Savitskaya became the second woman to enter space; she was also from the Soviet Union. Sally Ride became the next woman to enter space and the first woman to enter space through the United States program.