Creation
Main article: Creation of NASA
From 1946, the National Advisory Committee for Aeronautics (NACA) had been experimenting with rocket planes such as the supersonicBell X-1.[12] In the early 1950s, there was challenge to launch an artificial satellite for the International Geophysical Year (1957–58). An effort for this was the American Project Vanguard. After the Soviet launch of the world's first artificial satellite (Sputnik 1) on October 4, 1957, the attention of the United States turned toward its own fledgling space efforts. The U.S. Congress, alarmed by the perceived threat to national security and technological leadership (known as the "Sputnik crisis"), urged immediate and swift action; President Dwight D. Eisenhower and his advisers counseled more deliberate measures. This led to an agreement that a new federal agency mainly based on NACA was needed to conduct all non-military activity in space. The Advanced Research Projects Agency (ARPA) was created in February 1958 to develop space technology for military application.[13]
On July 29, 1958, Eisenhower signed the National Aeronautics and Space Act, establishing NASA. When it began operations on October 1, 1958, NASA absorbed the 46-year-old NACA intact; its 8,000 employees, an annual budget of US$100 million, three major research laboratories (Langley Aeronautical Laboratory, Ames Aeronautical Laboratory, and Lewis Flight Propulsion Laboratory) and two small test facilities.[14] A NASA seal was approved by President Eisenhower in 1959.[15] Elements of the Army Ballistic Missile Agency and the United States Naval Research Laboratory were incorporated into NASA. A significant contributor to NASA's entry into the Space Race with the Soviet Union was the technology from the German rocket program led by Wernher von Braun, who was now working for the Army Ballistic Missile Agency (ABMA), which in turn incorporated the technology of American scientist Robert Goddard's earlier works.[16] Earlier research efforts within the U.S. Air Force[14] and many of ARPA's early space programs were also transferred to NASA.[17] In December 1958, NASA gained control of the Jet Propulsion Laboratory, a contractor facility operated by the California Institute of Technology.[14]
Space flight programs
Main article: List of NASA missions
NASA has conducted many manned and unmanned spaceflight programs throughout its history. Unmanned programs launched the first American artificial satellites into Earth orbit for scientific and communications purposes, and sent scientific probes to explore the planets of the solar system, starting with Venus and Mars, and including "grand tours" of the outer planets. Manned programs sent the first Americans into low Earth orbit (LEO), won the Space Race with the Soviet Union by landing twelve men on the Moon from 1969 to 1972 in the Apollo program, developed a semi-reusable LEO Space Shuttle, and developed LEO space station capability by itself and with the cooperation of several other nations including post-Soviet Russia.
Manned programs
The experimental rocket-powered aircraft programs started by NACA were extended by NASA as support for manned spaceflight. This was followed by a one-man space capsule program, and in turn by a two-man capsule program. Reacting to loss of national prestige and securityfears caused by early leads in space exploration by the Soviet Union, in 1961 President John F. Kennedy proposed the ambitious goal "of landing a man on the Moon by the end of [the 60s], and returning him safely to the Earth." This goal was met in 1969 by the Apollo program, and NASA planned even more ambitious activities leading to a manned mission to Mars. However, reduction of the perceived threat and changing political priorities almost immediately caused the termination of most of these plans. NASA turned its attention to an Apollo-derived temporary space laboratory, and a semi-reusable Earth orbital shuttle. In the 1990s, funding was approved for NASA to develop a permanent Earth orbital space station in cooperation with the international community, which now included the former rival, post-Soviet Russia. To date, NASA has launched a total of 166 manned space missions on rockets, and thirteen X-15 rocket flights above the USAF definition of spaceflight altitude, 260,000 feet (80 km).[18]
X-15 rocket plane (1959–68)
Main article: North American X-15
The X-15 was an NACA experimental rocket-powered hypersonic research aircraft, developed in conjunction with the U.S. Air Force and Navy. The design featured a slender fuselage with fairings along the side containing fuel and early computerized control systems.[19]Requests for proposal were issued on December 30, 1954 for the airframe, and February 4, 1955 for the rocket engine. The airframe contract was awarded to North American Aviation in November 1955, and the XLR30 engine contract was awarded to Reaction Motors in 1956, and three planes were built. The X-15 was drop-launched from the wing of one of two NASA Boeing B-52 Stratofortresses, NB52Atail number 52-003, and NB52B, tail number 52-008 (known as the Balls 8). Release took place at an altitude of about 45,000 feet (14 km) and a speed of about 500 miles per hour (805 km/h).
Twelve pilots were selected for the program from the Air Force, Navy, and NACA (later NASA). A total of 199 flights were made between 1959 and 1968, resulting in the official world record for the highest speed ever reached by a manned powered aircraft (current as of 2014), and a maximum speed of Mach 6.72, 4,519 miles per hour (7,273 km/h).[20] The altitude record for X-15 was 354,200 feet (107.96 km).[21] Eight of the pilots were awarded Air Force astronaut wings for flying above 260,000 feet (80 km), and two flights byJoseph A. Walker exceeded 100 kilometers (330,000 ft), qualifying as spaceflight according to the International Aeronautical Federation. The X-15 program employed mechanical techniques used in the later manned spaceflight programs, including reaction control system jets for controlling the orientation of a spacecraft, pressurized space suits, and horizon definition for navigation.[21] The reentry and landing data collected were valuable to NASA for designing the Space Shuttle.[19]
Project Mercury (1959–63)
Main article: Project Mercury
Shortly after the Space Race began, an early objective was to get a person into Earth orbit as soon as possible, therefore the simplest spacecraft that could be launched by existing rockets was favored. U.S. Air Force's Man in Space Soonest program looked at many manned spacecraft designs, ranging from rocket planes like the X-15, to small ballisticspace capsules.[22] By 1958, the space plane concepts were eliminated in favor of the ballistic capsule.[23]
When NASA was created that same year, the Air Force program was transferred to it and renamed Project Mercury. The first seven astronauts were selected among candidates from the Navy, Air Force and Marine test pilot programs. On May 5, 1961, astronaut Alan Shepard became the first American in space aboard Freedom 7, launched by aRedstone booster on a 15-minute ballistic (suborbital) flight.[24] John Glenn became the first American to be launched into orbit by an Atlas launch vehicle on February 20, 1962 aboard Friendship 7.[25] Glenn completed three orbits, after which three more orbital flights were made, culminating in L. Gordon Cooper's 22-orbit flight Faith 7, May 15–16, 1963.[26]
The Soviet Union (USSR) competed with its own single-pilot spacecraft, Vostok. They beat the U.S. for the first man in space, by launching cosmonaut Yuri Gagarin into a single Earth orbit aboard Vostok 1 in April 1961, one month before Shepard's flight.[27] In August 1962, they achieved an almost four-day record flight with Andriyan Nikolayev aboard Vostok 3, and also conducted a concurrent Vostok 4 mission carrying Pavel Popovich.
Project Gemini (1961–66)
Main article: Project Gemini
Based on studies to grow the Mercury spacecraft capabilities to long-duration flights, developing space rendezvous techniques, and precision Earth landing, Project Gemini was started as a two-man program in 1962 to overcome the Soviets' lead and to support the Apollo manned lunar landing program, adding extravehicular activity (EVA) and rendezvous and docking to its objectives. The first manned Gemini flight, Gemini 3, was flown by Gus Grissom and John Young on March 23, 1965.[28] Nine missions followed in 1965 and 1966, demonstrating an endurance mission of nearly fourteen days, rendezvous, docking, and practical EVA, and gathering medical data on the effects of weightlessness on humans.[29][30]
Under the direction of Soviet Premier Nikita Khrushchev, the USSR competed with Gemini by converting their Vostok spacecraft into a two- or three-man Voskhod. They succeeded in launching two manned flights before Gemini's first flight, achieving a three-cosmonaut flight in 1963 and the first EVA in 1964. After this, the program was then canceled, and Gemini caught up while spacecraft designer Sergei Korolev developed theSoyuz spacecraft, their answer to Apollo.
Project Apollo (1961–72)
Main article: Apollo program
The U.S public's perception of the Soviet lead in putting the first man in space, motivated President John F. Kennedy to ask the Congress on May 25, 1961 to commit the federal government to a program to land a man on the Moon by the end of the 1960s, which effectively launched the Apollo program.[31]
Apollo was one of the most expensive American scientific programs ever. It cost more than $20 billion in 1960s dollars[32] or an estimated $205 billion in present-day US dollars.[33] (In comparison, the Manhattan Project cost roughly $26.2 billion, accounting for inflation.)[33][34] It used the Saturn rockets as launch vehicles, which were far bigger than the rockets built for previous projects.[35] The spacecraft was also bigger; it had two main parts, the combined command and service module (CSM) and the lunar landing module (LM). The LM was to be left on the Moon and only the command module (CM) containing the three astronauts would eventually return to Earth.
The second manned mission, Apollo 8, brought astronauts for the first time in a flight around the Moon in December 1968.[36] Shortly before, the Soviets had sent an unmanned spacecraft around the Moon.[37] On the next two missions docking maneuvers that were needed for the Moon landing were practiced[38][39] and then finally the Moon landing was made on the Apollo 11mission in July 1969.[40]
The first person to stand on the Moon was Neil Armstrong, who was followed by Buzz Aldrin, while Michael Collins orbited above. Five subsequent Apollo missions also landed astronauts on the Moon, the last in December 1972. Throughout these six Apollo spaceflights, twelve men walked on the Moon. These missions returned a wealth of scientific data and 381.7 kilograms (842 lb) of lunar samples. Topics covered by experiments performed included soil mechanics, meteoroids, seismology, heat flow, lunar ranging, magnetic fields, and solar wind.[41] The Moon landing marked the end of the space race and as a gesture, Armstrong mentioned mankind[42] when he stepped down on the Moon.
Apollo set major milestones in human spaceflight. It stands alone in sending manned missions beyondlow Earth orbit, and landing humans on another celestial body.[43] Apollo 8 was the first manned spacecraft to orbit another celestial body, while Apollo 17 marked the last moonwalk and the last manned mission beyond low Earth orbitto date. The program spurred advances in many areas of technology peripheral to rocketry and manned spaceflight, including avionics, telecommunications, and computers. Apollo sparked interest in many fields of engineering and left many physical facilities and machines developed for the program as landmarks. Many objects and artifacts from the program are on display at various locations throughout the world, notably at the Smithsonian's Air and Space Museums.
Skylab (1965–79)
Main article: Skylab
Skylab was the United States' first and only independently built space station.[44] Conceived in 1965 as a workshop to be constructed in space from a spent Saturn IB upper stage, the 169,950 lb (77,088 kg) station was constructed on Earth and launched on May 14, 1973 atop the first two stages of a Saturn V, into a 235-nautical-mile (435 km) orbit inclined at 50° to the equator. Damaged during launch by the loss of its thermal protection and one electricity-generating solar panel, it was repaired to functionality by its first crew. It was occupied for a total of 171 days by 3 successive crews in 1973 and 1974.[44] It included a laboratory for studying the effects of microgravity, and a solar observatory.[44]NASA planned to have a Space Shuttle dock with it, and elevate Skylab to a higher safe altitude, but the Shuttle was not ready for flight before Skylab's re-entry on July 11, 1979.[45]
To save cost, NASA used one of the Saturn V rockets originally earmarked for a canceled Apollo mission to launch the Skylab. Apollo spacecraft were used for transporting astronauts to and from the station. Three three-man crews stayed aboard the station for periods of 28, 59, and 84 days. Skylab's habitable volume was 11,290 cubic feet (320 m3), which was 30.7 times bigger than that of the Apollo Command Module.[45]
Apollo-Soyuz Test Project (1972–75)
Main article: Apollo-Soyuz Test Project
On May 24, 1972, US President Richard M. Nixon and Soviet Premier Alexei Kosygin signed an agreement calling for a joint manned space mission, and declaring intent for all future international manned spacecraft to be capable of docking with each other.[46] This authorized the Apollo-Soyuz Test Project (ASTP), involving the rendezvous and docking in Earth orbit of a surplus Apollo Command/Service Module with aSoyuz spacecraft. The mission took place in July 1975. This was the last US manned space flight until the first orbital flight of the Space Shuttlein April 1981.[47]
The mission included both joint and separate scientific experiments, and provided useful engineering experience for future joint US–Russian space flights, such as the Shuttle–Mir Program[48] and the International Space Station.
Space Shuttle program (1972–2011)
Main article: Space Shuttle program
The Space Shuttle became the major focus of NASA in the late 1970s and the 1980s. Planned as a frequently launchable and mostly reusable vehicle, four space shuttle orbiters were built by 1985. The first to launch, Columbia, did so on April 12, 1981,[49] the 20th anniversary of the first space flight by Yuri Gagarin.[50]
Its major components were a spaceplane orbiter with an external fuel tank and two solid-fuel launch rockets at its side. The external tank, which was bigger than the spacecraft itself, was the only component that was not reused. The shuttle could orbit in altitudes of 185–643 km (115–400 miles)[51] and carry a maximum payload (to low orbit) of 24,400 kg (54,000 lb).[52] Missions could last from 5 to 17 days and crews could be from 2 to 8 astronauts.[51]
On 20 missions (1983–98) the Space Shuttle carried Spacelab, designed in cooperation with the European Space Agency (ESA). Spacelab was not designed for independent orbital flight, but remained in the Shuttle's cargo bay as the astronauts entered and left it through an airlock.[53] Another famous series of missions were the launch and latersuccessful repair of the Hubble Space Telescope in 1990 and 1993, respectively.[54]
In 1995, Russian-American interaction resumed with the Shuttle-Mir missions (1995–1998). Once more an American vehicle docked with a Russian craft, this time a full-fledged space station. This cooperation has continued with Russia and the United States as two of the biggest partners in the largest space station built: the International Space Station(ISS). The strength of their cooperation on this project was even more evident when NASA began relying on Russian launch vehicles to service the ISS during the two-year grounding of the shuttle fleet following the 2003 Space Shuttle Columbia disaster.
The Shuttle fleet lost two orbiters and 14 astronauts in two disasters: Challenger in 1986, and Columbia in 2003.[55] While the 1986 loss was mitigated by building the Space Shuttle Endeavour from replacement parts, NASA did not build another orbiter to replace the second loss.[55] NASA's Space Shuttle program had 135 missions when the program ended with the successful landing of the Space Shuttle Atlantis at the Kennedy Space Center on July 21, 2011. The program spanned 30 years with over 300 astronauts sent into space.[56]
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