Vostok Program

On April 12, 1961, with a shout of 'Poyekhali!' (“Let’s go!”) 27-year-old Yuri Gagarin lifted off from the USSR for a 108-minute, one-orbit flight aboard Vostok 1. All went well during this first piloted spaceflight until the equipment module ejected. By some accounts, the cable bundle linking the module to the capsule failed to detach, causing the two parts of Vostok 1 to tumble wildly about each other. After about 10 minutes they separated, and Gagarin landed safely.

Vostok 2, lasting from August 6 to August 7, 1961, was a 24.3-hour flight by 25-year-old cosmonaut Gherman Titov. During his 17 orbits, Titov became the first human to eat, sleep, and experience sickness while in orbit (see Aerospace Medicine: Space Medicine). Vostok 3 was postponed for a year because Soviet doctors wished to study the physiological effects of spaceflight. Andrian Nikolayev made a 64-orbit flight aboard Vostok 3 from August 11 to August 15, 1962. Vostok 4 was launched on August 12, 1962, while Vostok 3 was still in orbit. The Vostok capsules could not maneuver, but Soviet controllers launched Vostok 4 so that it passed within 6.5 km (4.0 mi) of Vostok 3. Vostok 4 carried cosmonaut Pavel Popovich and landed safely on August 15, 1962.

At almost five days in duration, Vostok 5 remains the longest solo space mission ever. Valeri Bykovskii flew alone for 81 orbits and 3 million km (2 million mi) from June 14 to June 19, 1963. Valentina Tereshkova became the first woman in space when she flew aboard Vostok 6 from June 16 to June 19, 1963. On its first orbit, Vostok 6 passed within 5 km (3 mi) of Vostok 5. Tereshkova flew on for 2 days 22 hours, covering 1.9 million km (1.2 million mi) in 48 orbits. Soviet engineers planned a Vostok 7 flight that would last a week, but this was canceled so they could concentrate on the Vostok's successor, the Voskhod spacecraft (see Voskhod Program).