152
3 A Brief History of Space Flight
the module. The instrument module, with a cylindrical shape, is equipped with 18
spherical high-pressure nitrogen and oxygen cylinders, retro-thrust engines, internal
propellant tanks and communication antennas, etc. As a purely experimental vehicle,
the Vostok spacecraft had to safely carry an astronaut into orbit and return the astronaut to the Earth. The main flight control function was limited to orienting the
spacecraft tail first for the firing of the braking engine prior to reentry into the atmosphere. The braking engine, whose firing would be commanded by a programming
timer, had to slow down the spacecraft by about 140 m/s to ensure the safe return of
the vehicle. Since the successful completion of the reentry maneuver meant life or
death for the astronaut and the braking engine could not be backed up by any other
hardware, the Vostok spacecraft would be launched into an orbit with 180 km by
235 km. At that altitude, the density of the upper atmosphere would be enough to
slow down and send the spacecraft back to the Earth roughly 5 days after launch,
with a margin of error of 2.5 days. It is the reason why the spacecraft must carry
enough food, water, air and power onboard to support a 10-day mission.
From May to December 1960, the Soviet Union had successively launched five
unmanned prototypes of the Vostok spacecrafts, officially named from KorablSputnik-1 to Korabl-Sputnik-5, to practically test the reliability of the spacecraft’s
design performance, life safety, and recovery and landing. However, except for the
successful test of Korabl-Sputnik-3, the tests of the other four spacecrafts were
ended in various failures. For this reason, by improving the spacecraft’s designs, two
unmanned flight tests were added. Two spacecrafts Korabl-Sputnik-6 and KorablSputnik-7 were launched respectively on March 9 and 25, 1961, carrying with a dog
each. Eventually, the two flight tests were very perfect and both dogs safely returned
to the ground.
Although the success rate of the spacecrafts certified to carry a human was so
dismal, at 9:07 Moscow time on April 12, 1961, the astronaut Yuri Alekseyevich
Gagarin (´pii Alekc´ eeviq Gag´ apin, 1934−1968)by the Vostok-1 spacecraft
was launched from site 1 of the Tyuratam (Baikonur launch site) on schedule. Gagarin
flew one circle around the Earth for one hour 46 min, and at 10:53 Moscow time,
safely landed at a position of approximately 25 km southwest of Engels town in the
Ternovsky District near Saratov, the USSR. As a result, Gagarin achieved the dream
of human space flight for thousands of years for the first time. It was also another
significant leap in space technical development history for humanity. Apparently, it
was shown that the Soviet Union beat the United States again in the Space Race on
the manned Earth orbit flight.
Since then, from August 1961 to June 1963, five Vostok series spacecrafts
were sequentially launched to carry out a series of scientific researches and tests,
including impacts of long-time in-orbit flight on the astronauts, spacecrafts onorbit formation flight, space medicine and earth observation. Particularly, the
world’s first female astronaut, Valentina Vladimirovna Tereshkova (Balent´ina
Blad´imipovna Tepexk´ ova, 1937−) by the Vostok-6 spacecraft, was launch on
June 16, 1963, and flew in orbit for three days. Meanwhile, Tereshkova conducted
the tests of formation flight and space medicine together with the astronaut Valery
Bykovsky who was on the Vostok-5 launched before.
3 A Brief History of Space Flight
the module. The instrument module, with a cylindrical shape, is equipped with 18
spherical high-pressure nitrogen and oxygen cylinders, retro-thrust engines, internal
propellant tanks and communication antennas, etc. As a purely experimental vehicle,
the Vostok spacecraft had to safely carry an astronaut into orbit and return the astronaut to the Earth. The main flight control function was limited to orienting the
spacecraft tail first for the firing of the braking engine prior to reentry into the atmosphere. The braking engine, whose firing would be commanded by a programming
timer, had to slow down the spacecraft by about 140 m/s to ensure the safe return of
the vehicle. Since the successful completion of the reentry maneuver meant life or
death for the astronaut and the braking engine could not be backed up by any other
hardware, the Vostok spacecraft would be launched into an orbit with 180 km by
235 km. At that altitude, the density of the upper atmosphere would be enough to
slow down and send the spacecraft back to the Earth roughly 5 days after launch,
with a margin of error of 2.5 days. It is the reason why the spacecraft must carry
enough food, water, air and power onboard to support a 10-day mission.
From May to December 1960, the Soviet Union had successively launched five
unmanned prototypes of the Vostok spacecrafts, officially named from KorablSputnik-1 to Korabl-Sputnik-5, to practically test the reliability of the spacecraft’s
design performance, life safety, and recovery and landing. However, except for the
successful test of Korabl-Sputnik-3, the tests of the other four spacecrafts were
ended in various failures. For this reason, by improving the spacecraft’s designs, two
unmanned flight tests were added. Two spacecrafts Korabl-Sputnik-6 and KorablSputnik-7 were launched respectively on March 9 and 25, 1961, carrying with a dog
each. Eventually, the two flight tests were very perfect and both dogs safely returned
to the ground.
Although the success rate of the spacecrafts certified to carry a human was so
dismal, at 9:07 Moscow time on April 12, 1961, the astronaut Yuri Alekseyevich
Gagarin (´pii Alekc´ eeviq Gag´ apin, 1934−1968)by the Vostok-1 spacecraft
was launched from site 1 of the Tyuratam (Baikonur launch site) on schedule. Gagarin
flew one circle around the Earth for one hour 46 min, and at 10:53 Moscow time,
safely landed at a position of approximately 25 km southwest of Engels town in the
Ternovsky District near Saratov, the USSR. As a result, Gagarin achieved the dream
of human space flight for thousands of years for the first time. It was also another
significant leap in space technical development history for humanity. Apparently, it
was shown that the Soviet Union beat the United States again in the Space Race on
the manned Earth orbit flight.
Since then, from August 1961 to June 1963, five Vostok series spacecrafts
were sequentially launched to carry out a series of scientific researches and tests,
including impacts of long-time in-orbit flight on the astronauts, spacecrafts onorbit formation flight, space medicine and earth observation. Particularly, the
world’s first female astronaut, Valentina Vladimirovna Tereshkova (Balent´ina
Blad´imipovna Tepexk´ ova, 1937−) by the Vostok-6 spacecraft, was launch on
June 16, 1963, and flew in orbit for three days. Meanwhile, Tereshkova conducted
the tests of formation flight and space medicine together with the astronaut Valery
Bykovsky who was on the Vostok-5 launched before.