160
3 A Brief History of Space Flight
Since the core module was launched by the USSR into the Earth orbit on February
20, 1986, over the next decade the world’s first modular space station Mir had
been building by continually sending the additional modules aloft to assemble to
the core unit. The Mir’s core module resembled its simpler predecessors in the
Salyut series, with the form of a stepped cylinder, a length of about 13 m and a
maximum diameter of 4.2 m and had six docking ports that accommodated not only
a succession of crewed spacecrafts and cargo ferries but also permanently attached
expansion modules equipped for scientific research. During 14 years in orbit, the
Mir space station had been docked with 39 vehicles, including 1 Soyuz T-15, 29
Soyuz TM series, 1 Discovery Shuttle, 7 Atlantis Shuttles and 1 Endeavour Shuttle,
and conducted one approaching and maneuvering demonstration with the Discovery
Shuttle. The Mir hosted more than 100 people from 12 countries, of which included
57 American astronauts during 1995−1998 as a part of the Mir-Space Shuttle cooperative endeavor, and served as a microgravity research laboratory in which the crews
conducted experiments in biology, human biology, physics, astronomy, meteorology
and spacecraft systems, with a goal of developing technologies required for permanent occupation of space. On March 23, 2001, the abandoned Mir space station made
a controlled reentry, with the surviving pieces falling into the Pacific Ocean.
In the 1970s, the United States had built its first space station Skylab, and began to
conceive a reusable spacecraft, Space Shuttle. In May 1973, the Skylab was launched
into orbit, s which three successive three-man crews lived respectively for 28, 56 and
84 days in the orbit. The astronauts aboard the Skylab conducted 270 experiments
in biomedical and life science, solar astronomy, Earth observations and materials
processing, among which the most important experiments were investigations on the
astronauts’ physiological responses to long-duration space flight. In July 1979, the
Skylab re-entered the atmosphere due to its orbit decaying and burned up. Finally,
its remnants scattered over the Indian Ocean and a settled area of Western Australia,
but fortunately nobody was hurt.
The Space Shuttle, whose official program name was Space Transportation System
(STS), was taken from a 1969 plan for a system of reusable spacecraft of which it
was the only item funded for development by NASA. It consists of three major
components: a winged orbiter that carries both crew and cargo; an external tank
containing liquid hydrogen and liquid oxygen for the orbiter’s three main rocket
engines; a pair of large, solid-propellant, trap-on booster rockets. At the lift-off,
the entire system weighed 2000 metric tons and stood 56-m high. On April 12,
1981, the first orbiter, the Space Shuttle Columbia, was launched from the Kennedy
Space Center to carry out orbital flight tests, leading to operational flights beginning in 1982. Besides the Columbia, Challenger, Discovery and Atlantis together
formed a fleet of four orbiters, and were sequentially put into service. On January
28, 1986, the Challenger with seven crews exploded shortly after lift-off, killing
all aboard including six astronauts and a schoolteacher who had been selected to
fly via NASA’s “Teacher in Space” program. In 1992, a replacement orbiter for the
destroyed Challenger, Endeavour, flew its first mission. The operational missions of
the five complete Space Shuttles included launching numerous satellites, interplanetary probes, and the Hubble Space Telescope (HST); conducting science experiments
3 A Brief History of Space Flight
Since the core module was launched by the USSR into the Earth orbit on February
20, 1986, over the next decade the world’s first modular space station Mir had
been building by continually sending the additional modules aloft to assemble to
the core unit. The Mir’s core module resembled its simpler predecessors in the
Salyut series, with the form of a stepped cylinder, a length of about 13 m and a
maximum diameter of 4.2 m and had six docking ports that accommodated not only
a succession of crewed spacecrafts and cargo ferries but also permanently attached
expansion modules equipped for scientific research. During 14 years in orbit, the
Mir space station had been docked with 39 vehicles, including 1 Soyuz T-15, 29
Soyuz TM series, 1 Discovery Shuttle, 7 Atlantis Shuttles and 1 Endeavour Shuttle,
and conducted one approaching and maneuvering demonstration with the Discovery
Shuttle. The Mir hosted more than 100 people from 12 countries, of which included
57 American astronauts during 1995−1998 as a part of the Mir-Space Shuttle cooperative endeavor, and served as a microgravity research laboratory in which the crews
conducted experiments in biology, human biology, physics, astronomy, meteorology
and spacecraft systems, with a goal of developing technologies required for permanent occupation of space. On March 23, 2001, the abandoned Mir space station made
a controlled reentry, with the surviving pieces falling into the Pacific Ocean.
In the 1970s, the United States had built its first space station Skylab, and began to
conceive a reusable spacecraft, Space Shuttle. In May 1973, the Skylab was launched
into orbit, s which three successive three-man crews lived respectively for 28, 56 and
84 days in the orbit. The astronauts aboard the Skylab conducted 270 experiments
in biomedical and life science, solar astronomy, Earth observations and materials
processing, among which the most important experiments were investigations on the
astronauts’ physiological responses to long-duration space flight. In July 1979, the
Skylab re-entered the atmosphere due to its orbit decaying and burned up. Finally,
its remnants scattered over the Indian Ocean and a settled area of Western Australia,
but fortunately nobody was hurt.
The Space Shuttle, whose official program name was Space Transportation System
(STS), was taken from a 1969 plan for a system of reusable spacecraft of which it
was the only item funded for development by NASA. It consists of three major
components: a winged orbiter that carries both crew and cargo; an external tank
containing liquid hydrogen and liquid oxygen for the orbiter’s three main rocket
engines; a pair of large, solid-propellant, trap-on booster rockets. At the lift-off,
the entire system weighed 2000 metric tons and stood 56-m high. On April 12,
1981, the first orbiter, the Space Shuttle Columbia, was launched from the Kennedy
Space Center to carry out orbital flight tests, leading to operational flights beginning in 1982. Besides the Columbia, Challenger, Discovery and Atlantis together
formed a fleet of four orbiters, and were sequentially put into service. On January
28, 1986, the Challenger with seven crews exploded shortly after lift-off, killing
all aboard including six astronauts and a schoolteacher who had been selected to
fly via NASA’s “Teacher in Space” program. In 1992, a replacement orbiter for the
destroyed Challenger, Endeavour, flew its first mission. The operational missions of
the five complete Space Shuttles included launching numerous satellites, interplanetary probes, and the Hubble Space Telescope (HST); conducting science experiments