Manned Spacecraft

The first and simplest crewed spacecraft were designed to carry a single passenger. In the Soviet Union, these vehicles were designated by the code-name Vostok ("East") and in the United States they were known as Mercury spacecraft. The first Vostok flight was piloted by Yuri A. Gargarin and was launched from the Tyuratam kosmodrome (space center) on April 12, 1961. In all, a total of six Vostok flights were completed over a period of just over two years. The last of these carried the first woman to fly in outer space, Valentina Tereshkova. Tereshkova spent three days in Vostok 6 between June 16 and 19, 1963.

The Vostok spacecraft was essentially a spherical cabin containing a single seat and all equipment necessary to support life and communicate with Earth. It also held an ejection seat. The ejection seat activated at an altitude of about 23,000 ft (7,000 m), allowing the pilot to experience a soft parachute landing separately from his or her spacecraft.

The U.S. Mercury program followed a pattern similar to that of the Vostok series. In the first Mercury flight, American astronaut Alan B. Shephard traveled for 15 minutes in a suborbital flight—a long, parabolic arc over the Atlantic ocean—only three weeks after Yuri Gargarin's trip. Nine months after Shepard's flight, John Glenn became the first American to orbit the Earth, in a space capsule he named Friendship 7 (referring to the first seven U.S. astronauts, who trained together). The Mercury spacecraft was a double-walled, bell-shaped capsule made of titanium and nickel alloy with an insulating ceramic outer coat and an ablative heat shield over the bottom of the bell to dissipate the friction of atmospheric reentry.