Spacecraft, Manned
During the late 1950s the Soviet Union and the United States confined their Cold War competition for dominance in space to unmanned satellites. The Soviets successfully launched the first satellite, Sputnik 1, on October 4, 1957, and the U.S. quickly answered the challenge with their own Explorer 1. President Dwight D. Eisenhower, impressed by the success of Explorer 1 and determined that this new technology should remain outside the control of the military, sponsored the creation of the National Aeronautics and Space Administration (NASA). However, he remained unconvinced that humans belonged in space and, despite the arguments of such eminent scientists as Wernher von Braun to the contrary, believed that unmanned space flight should be NASA's primary pursuit.
Yuri Gagarin Unlike the United States, the Soviet Union actively pursued manned flight. In 1959 and 1960 a design team headed by Sergei Kolorev constructed several prototypes of the first manned spacecraft, Vostok ("East"). Soviet scientists also launched several live dogs in Sputnik satellites to test the possible stresses that humans might undergo in space. The most famous of these canine travellers was Laika, the first living creature to ascend into space. Finally, on April 12, 1961, Vostok 1 lifted off from the Baikonur Cosmodrome carrying Yuri Gagarin, a Soviet Air Force test pilot and the first astronaut. He circled the planet for 108 minutes then reentered Earth's atmosphere. At about 4 miles (6.4 km) above ground, his ejection seat propelled him from the capsule, and he parachuted to the ground.
Project Mercury Gagarin's flight galvanized the American public and the new administration of John F. Kennedy. Concerned that the United States' leadership in technology had been compromised, President Kennedy announced the goal of landing an American on the Moon within eight years. As a result, the manned Mercury space program, approved in 1958 after much controversy, was accelerated. Commissioned by NASA prior to Gagarin's flight, the Space Task Group at Langley Research Center had modified the military's Redstone and Atlas rocket s for the launching of manned flights and developed Mercury's unique bell-shaped capsule that could withstand the incredible heat caused by the friction of reentry into the atmosphere. Possible failure on board the Mercury capsule was compensated for by backup systems and, as a last resort, the ability of the astronaut to control flight manually. Each of the original seven astronauts mastered one aspect of the launch, and all united together on certain key design issues. For example, they lobbied to have a window installed on the capsule despite the resistance of engineers.
On May 5, 1961, Alan Shepard (1923-) ascended into suborbital flight on board Freedom 7, spending 15 minutes and 22 seconds in flight before descending to Earth. Unlike Gagarin, he remained in the spacecraft until it splashed down in the Atlantic and a Navy ship rendezvoused with the capsule. Virgil ("Gus") Grissom (1926-1967) went on another such flight in July of that year. John Glenn (1921-) became the first American to orbit the Earth on February 20, 1962, circling the planet three times in less than five hours. As a result of this accomplishment, Glenn became one of the most celebrated national heroes since Charles Lindbergh, and the U.S. manned space program gained valuable public and media support.
Gemini and Voskhod Project Mercury gave way to the Gemini program in 1964, the goal of which was to design a two-man spacecraft and develop the skills and technology necessary for achieving a lunar landing. However, the Soviet Union had once again overtaken the Americans, launching Voskhod ("Sunrise"), its new three-man spacecraft in October 1964, well before the first Gemini flight. In March 1965 Soviet cosmonaut Alexei Leonov (1934-) also took the first space walk, spending 10 minutes outside the Voskhod capsule connected to the craft by only telephone and telemetry cables. The United States Gemini spacecraft consisted of two sections: a manned capsule capable of carrying two astronauts and an adapter section. Between March 1965 and November 1966 ten manned Gemini spacecraft were sent into orbit in order to extend mission times, perfect and practice orbital maneuvering, rendezvous, and docking techniques, and train astronauts in extra-vehicular activity. There were several highlights: on Gemini 4 Ed White (1930-1967) took a 21-minute spacewalk, Gemini 6 and 7 rendezvoused together in space, and Gemini 10 docked with an Agena rocket and fired its engine for a new orbit.
Apollo NASA applied the advances made during the Gemini missions to the Apollo spacecraft, the first manned vehicle to land on the Moon. Developed by North American Aviation, the craft consisted of three parts: the command module where three astronauts would travel; the service module that carried fuel, oxygen, water, the electrical system, and communications equipment; and the lunar module, which would make the actual descent and lift-off from the Moon's surface.
The first Apollo missions would consist of testing the command and service modules as well as testing the ability of the command and lunar modules to rendezvous and dock. In 1967, however, disaster struck when, on a ground test of Apollo 1, three astronauts--Gus Grissom, Ed White, and Roger Chaffee (1935-1967)--died after an electrical spark ignited the pure oxygen of their cabin, causing fire and toxic fumes to spread in seconds. As a result of this tragedy the program was delayed for over two years as questions arose concerning the spacecraft's safety (Grissom at one point had hung a lemon on the craft), and the pressures placed on designers by government officials eager to surpass the Soviets. During that period over 1,500 modifications were made to the command module to ensure the astronauts' safety.
The Apollo spacecraft was ready for flight in October 1968, and, after several " rehearsal" flights, Apollo 11 was launched on July 16, 1969, with astronauts Neil Armstrong (1930-), Michael Collins (1930-), and Edwin "Buzz" Aldrin (1930-) on board. Four days later, Aldrin and Armstrong descended into the Sea of Tranquility in the lunar module Eagle. As Armstrong stepped down onto the Moon's surface he uttered the now-famous words "that's one small step for man, one giant leap for mankind." The culmination of nearly a decade of technological advances, Apollo 11 has been described as the greatest achievement of the modern world.
Soyuz While the United States had been developing the Apollo spacecraft, the Soviet Union had begun work on Soyuz (the Russian word meaning "Union"). Like Apollo, Soyuz consisted of three modules for orbit, descent, and storage. Also, unlike earlier Soviet spacecraft, cosmonauts could control its navigation and guidance systems. Problems, however, plagued the program and the spacecraft's maiden flight was repeatedly delayed. Finally in April 1967--three months after the Apollo 1 fire-- Soyuz 1 was launched. Yet little over 24 hours later, the spacecraft crashed to Earth, with cosmonaut Vladimir Komarov (1927-1967) on board. Although Soviet officials denied that design flaws were to blame for the crash, Western analysts concluded that the controls of the craft had failed, causing it to tumble wildly and become tangled in its parachute lines. This disaster, coupled with the death of the visionary Kolorev a year earlier, effectively halted the Soviet space program.
By the time of their first flight following Soyuz 1 some 18 months later, the Soviets had unofficially conceded defeat in the race for the Moon. They focused instead on establishing the first orbiting space station, Salyut ("Salute").
Space Stations The Russians launched their first space station, Salyut 1, in April 1971. Orbiting approximately 200 miles (321 km) above the Earth, the station was powered by two solar panels and divided into several different modules, three of which were pressurized. While cosmonauts onboard Soyuz 10 were unable to enter the station (Soviet officials claimed otherwise), the three-man crew of Soyuz 11 successfully entered Salyut 1 on June 7, 1971.
On board, the cosmonauts used a telescope and spectrograph for observations and conducted experiments in plant growth. Their highly successful three-week stay set a new record for human endurance in space. Yet during their reentry into Earth's atmosphere, a cabin seal released prematurely and the spacecraft lost air pressure. The three crew members-- Georgi T. Dobrovolsky (1928-1971), Viktor I. Patsayev (1933-1971), and Vladislav N. Volkov (1935-1971)--had not been issued pressure suits and suffocated instantly. As a result of this disaster, the Soviets were forced to allow Salyut 1 to fall out of its orbit and burn up in reentry, having lost the means of visiting and refueling the station.
Despite this major setback, they were eventually able to launch other Salyut stations as the decade progressed. By the early 1980s, the Soviet Union had begun to establish a significant lead in the duration of manned space flight using their Salyut stations. As an example of the Soviets' ability to keep people in space for extended periods of time, three cosmonauts stayed aloft in 1984 for 237 days, nearly three times longer than the American record of 84 days.
In 1986 the Soviets launched a new space station, Mir ("Peace"), which had less scientific equipment than Salyut but had better accommodations for its cosmonauts as well as improved life support and ventilation systems. Over the next three years, Mir cosmonauts carried out astronomical observations, materials processing and medical experiments, and extensive photography of the earth.
Following the initial flight of Salyut, the United States stepped up production of their own space station, Skylab. Unlike Soviet engineers, U.S. engineers chose not to start from scratch but rather to use the shell of an Apollo rocket tank as a "skeleton." The size of a small two-bedroom house, the station boasted comforts unheard of in spacecraft, including a shower, toilet, and sleep compartments.
Launched into orbit in May 1973, Skylab was powered by large solar panels similar to those found on Salyut, and a thin aluminum shield protected the station against micrometeorites and excessive solar heat. Soon after launch on May 14, 1973, scientists discovered that part of the shield had torn off, carrying with it one of the solar panels. Realizing the station was now seriously underpowered and was vulnerable to overheating from the Sun, NASA sent a three-man crew to meet the station. Working in space suits, the astronauts repaired the damage to the solar panel and deployed a hastily engineered sun shade. Now able to carry out their original mission, the crew conducted astronomical observations and biomedical experiments for 28 days. Two more missions took place before 1979 when Skylab reentered the Earth's atmosphere and disintegrated despite the efforts of NASA to save it.
The Space Shuttle When the Apollo program drew to a close in the mid-1970s, NASA presented Congress with three possible long range goals for manned spaceflight: a lunar-orbiting space station, a manned voyage to Mars, and a 50-person Earth-orbiting space station serviced by a fleet of reusable space shuttles. Although Congress rejected all three as too expensive, NASA officials were determined to at least win approval for the space shuttle. They approached the Department of Defense (DOD), and an agreement was struck which stipulated that the DOD help fund the project in return for use of the shuttle for military projects.
The idea of a reusable spacecraft dated back to the early 1950s with the development of the X series of high-altitude aircraft, and the actual design process for the space shuttle commenced in 1969 when engineer Robert Gilruth brought his idea of a reusable spacecraft to NASA engineer Maxime Faget. By 1977 Faget and his team had completed the development phase of the shuttle, and on April 12, 1981, the Columbia was successfully launched and returned to Earth for its second voyage on November 4, 1981.
About the size of a DC-9 commercial airliner, the Columbia and its sister shuttles were intended to serve as an economical transport for the development of manufacturing and large-scale commercial operations in space and the construction of a permanent space station. Although the shuttle program failed to meet the ambitious flight schedule set for it by government officials, the first 24 missions were flown successfully and the American public soon grew used to seeing shuttle launches on television. However, on January 28, 1986, the seemingly routine nature of space flight was shattered when the Challenger exploded a minute into the flight, killing all seven crew members. An investigation of the disaster revealed that the solid rocket's O-rings had become brittle in the cold weather, then had broken in flight, resulting in the explosion. The next shuttle did not fly again until nearly three years later, after some 400 modifications had been made to its design and its payload schedule revised. A replacement for the Challenger, the Endeavor, saw its first service in 1992.
Despite the resumption of shuttle flights, the future of manned spaceflight remains uncertain. In the United States the Challenger tragedy lost NASA its near-mythic reputation with the American public, and budget constraints have caused officials to seriously question the funding of multi-billion dollar space programs. And with the collapse of the Soviet Union, the "space race" --which drove the achievements of the 1960s--has ended as Russia struggles to achieve economic stability. However, several nations, including Russia, are forging ahead with plans to construct the so-called International Space Station (ISS), with initial in-orbit construction slated to begin in November 1998, with assembly to be completed by 2004.
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