Saturday 19 March 2011

History

Space race
Main article: Space Race

After the Soviet space program's 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. Several months of debate produced an agreement that a new federal agency was needed to conduct all non-military activity in space. The Advanced Research Projects Agency (ARPA) was also created at this time to develop space technology for military application.
NACA
Main article: National Advisory Committee for Aeronautics

From late 1957 to early 1958, the National Advisory Committee for Aeronautics (NACA) began studying what a new non-military space agency would entail, as well as what its role might be, and assigned several committees to review the concept.[6] On January 12, 1958, NACA organized a "Special Committee on Space Technology", headed by Guyford Stever.[6] Stever's committee included consultation from the Army Ballistic Missile Agency's large booster program, referred to as the Working Group on Vehicular Program, headed by Wernher von Braun,[6] a German scientist who became a naturalized US citizen after World War II.

On January 14, 1958, NACA Director Hugh Dryden published "A National Research Program for Space Technology" stating:[11]
“     It is of great urgency and importance to our country both from consideration of our prestige as a nation as well as military necessity that this challenge [Sputnik] be met by an energetic program of research and development for the conquest of space... It is accordingly proposed that the scientific research be the responsibility of a national civilian agency... NACA is capable, by rapid extension and expansion of its effort, of providing leadership in space technology.[11]     ”
Explorer 1, first US satellite

Launched on January 31, 1958, Explorer 1, officially Satellite 1958 Alpha, became the U.S.'s first earth satellite.[12] The Explorer 1 payload consisted of the Iowa Cosmic Ray Instrument without a tape data recorder which was not modified in time to make it onto the satellite.

On March 5, PSAC Chairman James Killian wrote a memorandum to President Eisenhower, entitled "Organization for Civil Space Programs", encouraging the creation of a civil space program based upon a "strengthened and redesignated" NACA which could expand its research program "with a minimum of delay."[11] In late March, a NACA report entitled "Suggestions for a Space Program" included recommendations for subsequently developing a hydrogen fluorine fueled rocket of 4,450,000 newtons (1,000,000 lbf) thrust designed with second and third stages.[6]

In April 1958, Eisenhower delivered to the U.S. Congress an executive address favoring a national civilian space agency and submitted a bill to create a "National Aeronautical and Space Agency."[6] NACA's former role of research alone would change to include large-scale development, management, and operations.[6] The U.S. Congress passed the bill, somewhat reworded, as the National Aeronautics and Space Act of 1958, on July 16.[6] Only two days later von Braun's Working Group submitted a preliminary report severely criticizing the duplication of efforts and lack of coordination among various organizations assigned to the United States' space programs.[6] Stever's Committee on Space Technology concurred with the criticisms of the von Braun Group (a final draft was published several months later, in October).[6]
NACA becomes NASA
President Kennedy, Vice President Johnson and other officials at the Launch Operations Center's LC-34 blockhouse during a 1962 tour

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.[13]

Elements of the Army Ballistic Missile Agency, of which von Braun's team was a part, and the 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 von Braun) which in turn incorporated the technology of Robert Goddard's earlier works.[14] Earlier research efforts within the U.S. Air Force[13] and many of ARPA's early space programs were also transferred to NASA.[15] In December 1958, NASA gained control of the Jet Propulsion Laboratory, a contractor facility operated by the California Institute of Technology.[13]
NASA programs
Main article: List of NASA missions
Manned programs
Project Mercury
May 5, 1961 launch of Redstone rocket and Freedom 7 with Alan Shepard on first US manned sub-orbital spaceflight
Main article: Project Mercury

Conducted under the pressure of the competition between the U.S. and the Soviet Union that existed during the Cold War, Project Mercury was initiated in 1958 and started NASA down the path of human space exploration with missions designed to discover if man could survive in space. Representatives from the U.S. Army, Navy, and Air Force were selected to provide assistance to NASA. Pilot selections were facilitated through coordination with U.S. defense research, contracting, and military test pilot programs. On May 5, 1961, astronaut Alan Shepard became the first American in space when he piloted Freedom 7 on a 15-minute suborbital flight.[16] John Glenn became the first American to orbit the Earth on February 20, 1962 during the flight of Friendship 7.[17] Three more orbital flights followed.
Project Gemini
Main article: Project Gemini

Project Gemini focused on conducting experiments and developing and practicing techniques required for lunar missions. The first Gemini flight with astronauts on board, Gemini 3, was flown by Gus Grissom and John Young on March 23, 1965.[18] Nine missions followed, showing that long-duration human space flight and rendezvous and docking with another vehicle in space were possible, and gathering medical data on the effects of weightlessness on humans.[19][20] Gemini missions included the first American spacewalks, and new orbital maneuvers including rendezvous and docking.
Apollo program
Main article: Apollo program
Apollo 11 Lunar Module Pilot Buzz Aldrin salutes US flag

The Apollo program landed the first humans on Earth's Moon. Apollo 11 landed on the moon on July 20, 1969 with astronauts Neil Armstrong and Buzz Aldrin, while Michael Collins orbited above. Five subsequent Apollo missions also landed astronauts on the Moon, the last in December 1972. In 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. Experiments included soil mechanics, meteoroids, seismic, heat flow, lunar ranging, magnetic fields, and solar wind experiments.[21]

Apollo set major milestones in human spaceflight. It stands alone in sending manned missions beyond low Earth orbit, and landing humans on another celestial body.[22] 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 orbit. 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
NASA's Skylab space station
Main article: Skylab

Skylab was the only space station launched into orbit solely by the United States.[23] The 100 short tons (91 t) station was in Earth orbit from 1973 to 1979, and was visited by crews three times, in 1973 and 1974.[23] It included a laboratory for studying the effects of microgravity, and a solar observatory.[23] A Space Shuttle was planned to dock with and elevate Skylab to a higher safe altitude, but Skylab reentered the atmosphere and was destroyed in 1979, before the first shuttle could be launched.[24]
ASTP
Main article: Apollo-Soyuz Test Project

The Apollo-Soyuz Test Project (ASTP) was the first joint flight of the U.S. and Soviet space programs. The mission took place in July 1975. For the United States, it was the last Apollo flight, as well as the last manned space launch until the flight of the first Space Shuttle in April 1981.[25] Manned Skylab and ASTP missions used the smaller Saturn IB with Apollo CSM, not the Saturn V.
Space Shuttle program
The first space shuttle launch, April 12, 1981 for STS-1
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.[26]
NASA "worm" logo used 1975–1992

In 1995 Russian-American interaction resumed with the Shuttle-Mir missions. Once more an American vehicle docked with a Russian craft, this time a full-fledged space station. This cooperation has continued to 2011, with Russia and the United States the two biggest partners in the largest space station ever 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.[27] 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.[27] NASA's shuttle program has made 133 successful launches as of March 2011[update].
International Space Station
The International Space Station
Main article: International Space Station program

The International Space Station (ISS) is an internationally developed research facility currently being assembled in Low Earth Orbit. On-orbit construction of the station began in 1998 and is scheduled to be completed by 2011, with operations continuing until at least 2015.[28] The station can be seen from the Earth with the naked eye, and, as of 2009[update], is the largest artificial satellite in Earth orbit, with a mass larger than that of any previous space station.

The ISS is operated as a joint project among NASA, the Russian Federal Space Agency, the Japan Aerospace Exploration Agency, the Canadian Space Agency, and the European Space Agency (ESA). Ownership and utilization of the space station is set out via several intergovernmental treaties and agreements, with the Russian Federation retaining full ownership of its own modules, and the rest of the station being allocated among the other international partners. Many of the ISS's modules were delivered by the Space Shuttle. Russian ISS modules launch and dock robotically, with the exception of Rassvet. All other modules were installed by ISS and shuttle crew using the SSRMS and EVAs.

The cost of the station project has been estimated by ESA as €100 billion over a course of 30 years, although cost estimates vary between 35 billion dollars and 160 billion dollars, making the ISS the most expensive object ever constructed.[citation needed]
Unmanned programs
Main article: Robotic spacecraft
Mariner program
Picture of Mariner 6
Main article: Mariner program

The Mariner program conducted by NASA launched a series of robotic interplanetary probes designed to investigate Mars, Venus and Mercury. The program included a number of firsts, including the first planetary flyby, the first pictures from another planet, the first planetary orbiter, and the first gravity assist maneuver.

Of the ten vehicles in the Mariner series, seven were successful and three were lost. The planned Mariner 11 and Mariner 12 vehicles evolved into Voyager 1 and Voyager 2 of the Voyager program, while the Viking 1 and Viking 2 Mars orbiters were enlarged versions of the Mariner 9 spacecraft. Other Mariner-based spacecraft, launched since Voyager, included the Magellan probe to Venus, and the Galileo probe to Jupiter. A second-generation Mariner spacecraft, called the Mariner Mark II series, eventually evolved into the Cassini-Huygens probe, now in orbit around Saturn.

All Mariner spacecraft were based on a hexagonal or octagonal "bus", which housed all of the electronics, and to which all components were attached, such as antennae, cameras, propulsion, and power sources. All probes except Mariner 1, Mariner 2 and Mariner 5 had TV cameras. The first five Mariners were launched on Atlas-Agena rockets, while the last five used the Atlas-Centaur. All Mariner-based probes after Mariner 10 used the Titan IIIE, Titan IV unmanned rockets or the Space Shuttle with a solid-fueled Inertial Upper Stage and multiple planetary flybys.
Pioneer program
Artist's conception of the Pioneer Venus Orbiter
Main article: Pioneer program

The Pioneer program is a series of NASA unmanned space missions that was designed for planetary exploration. There were a number of such missions in the program, but the most notable were Pioneer 10 and Pioneer 11, which explored the outer planets and left the solar system. Both carry a golden plaque, depicting a man and a woman and information about the origin and the creators of the probes, should any extraterrestrials find them someday.

Additionally, the Pioneer mission to Venus consisted of two components, launched separately. Pioneer Venus 1 or Pioneer Venus Orbiter was launched in 1978 and studied the planet for more than a decade after orbital insertion in 1978. Pioneer Venus 2 or Pioneer Venus Multiprobe sent four small probes into the Venusian atmosphere.
Voyager program
Voyager 1 launch, September 5, 1977
Main article: Voyager program

The Voyager program is a series of NASA unmanned space missions that consists of a pair of unmanned scientific probes, Voyager 1 and Voyager 2. They were launched in 1977 to take advantage of a favorable planetary alignment of the late 1970s. Although they were officially designated to study just Jupiter and Saturn, the two probes were able to continue their mission into the outer solar system. Both probes have achieved escape velocity from the solar system and will never return. Both missions have gathered large amounts of data about the gas giants of the solar system, of which little was previously known.

As of November 12, 2010 (2010 -11-12)[update], Voyager 1 was at a distance of 115.251 AU (17.242 billion km, or 10.712 billion miles), traveling away from both the Earth and the Sun at a speed of 17 kilometres (11 mi)/s, which corresponds to a greater specific orbital energy than any other probe.[29]
Viking program
Dr. Carl Sagan With the full-scale model of the Viking Lander
Main article: Viking program

The Viking program consisted of a pair of space probes sent to Mars—Viking 1 and Viking 2. Each vehicle was composed of two main parts, an orbiter designed to photograph the surface of Mars from orbit, and a lander designed to study the planet from the surface. The orbiters also served as communication relays for the landers once they touched down. Viking 1 was launched on August 20, 1975, and the second craft, Viking 2, was launched on September 9, 1975, both riding atop Titan III-E rockets with Centaur upper stages. By discovering many geological forms that are typically formed from large amounts of water, the Viking program caused a revolution in scientific ideas about water on Mars.

The primary objectives of the Viking orbiters were to transport the landers to Mars, perform reconnaissance to locate and certify landing sites, act as a communications relays for the landers, and to perform their own scientific investigations. The orbiter, based on the earlier Mariner 9 spacecraft, was an octagon approximately 2.5 m across. The total launch mass was 2,328 kilograms (5,130 lb), of which 1,445 kilograms (3,190 lb) were propellant and attitude control gas.
Helios probes
Main article: Helios probes

The Helios I and Helios II space probes, also known as Helios-A and Helios-B, were a pair of probes launched into heliocentric orbit for the purpose of studying solar processes. A joint venture of the Federal Republic of Germany (West Germany) and NASA, the probes were launched from Cape Canaveral Air Force Station, Florida, on Dec. 10, 1974, and Jan. 15, 1976, respectively. The probes are notable for setting a maximum speed record among spacecraft at 252,792 kilometres (157,078 mi)/h (157,078 mi/h or 43.63 mi/s or 70.22 kilometres (43.63 mi)/s or 0.000234c). The Helios space probes completed their primary missions by the early 1980s, but they continued to send data up to 1985. The probes are no longer functional but still remain in their elliptical orbit around the Sun.
Hubble Space Telescope
The Hubble Space Telescope
Main article: Hubble Space Telescope

The Hubble Space Telescope (HST) is a space telescope that was carried into orbit by a space shuttle in April 1990. It is named after American astronomer Edwin Hubble. Although not the first space telescope, Hubble is one of the largest and most versatile, and is well-known as both a vital research tool and a public relations boon for astronomy. The HST is a collaboration between NASA and the European Space Agency, and is one of NASA's Great Observatories, along with the Compton Gamma Ray Observatory, the Chandra X-ray Observatory, and the Spitzer Space Telescope.[30] The HST's success has paved the way for greater collaboration between the agencies.

The HST was created with a relatively small budget of $2 billion[31] and has continued operation since 1990, delighting both scientists and the public. Some of its images, such as the groundbreaking Hubble Deep Field, have become famous.
Magellan probe
The Magellan Probe prepared for launch
Main article: Magellan probe

The Magellan spacecraft was a space probe sent to the planet Venus, the first unmanned interplanetary spacecraft to be launched by NASA since its successful Pioneer Orbiter, also to Venus, in 1978. It was also the first of three deep-space probes to be launched on the Space Shuttle, and the first spacecraft to employ aerobraking techniques to lower its orbit.

Magellan created the first (and currently the best) high resolution mapping of the planet's surface features. Prior Venus missions had created low resolution radar globes of general, continent-sized formations. Magellan, performed detailed imaging and analysis of craters, hills, ridges, and other geologic formations, to a degree comparable to the visible-light photographic mapping of other planets.
Galileo probe
The Galileo probe
Main article: Galileo probe

Galileo was an unmanned spacecraft sent by NASA to study the planet Jupiter and its moons. It was launched on October 18, 1989 by the Space Shuttle Atlantis on the STS-34 mission. It arrived at Jupiter on December 7, 1995, a little more than six years later, via gravitational assist flybys of Venus and Earth.

Despite antenna problems, Galileo conducted the first asteroid flyby, discovered the first asteroid moon, was the first spacecraft to orbit Jupiter, and launched the first probe into Jupiter's atmosphere. Galileo's prime mission was a two-year study of the Jovian system. The spacecraft traveled around Jupiter in elongated ellipses, each orbit lasting about two months. The differing distances from Jupiter afforded by these orbits allowed Galileo to sample different parts of the planet's extensive magnetosphere. The orbits were designed for close up flybys of Jupiter's largest moons. Once Galileo's prime mission was concluded, an extended mission followed starting on December 7, 1997; the spacecraft made a number of daring close flybys of Jupiter's moons Europa and Io. The closest approach was 180 kilometres (110 mi) (112 mi) on October 15, 2001.

On September 21, 2003, after 14 years in space and eight years of service in the Jovian system, Galileo′s mission was terminated by sending the orbiter into Jupiter's atmosphere at a speed of nearly 50 kilometers per second to avoid any chance of it contaminating local moons with bacteria from Earth. Of particular interest was the ice-crusted moon Europa, which, thanks to Galileo, scientists now suspect harbors a salt water ocean beneath its surface.
Artist's conception of the Mars Global Surveyor
Mars Global Surveyor
Main article: Mars Global Surveyor

The Mars Global Surveyor (MGS) was developed by NASA's Jet Propulsion Laboratory and launched November 1996. It began the United States' return to Mars after a 10-year absence. It completed its primary mission in January 2001 and was in its third extended mission phase when, on November 2, 2006, the spacecraft failed to respond to commands. In January 2007 NASA officially ended the mission.

The Surveyor spacecraft used a series of high-resolution cameras to explore the surface of Mars during its mission, returning more than 240,000 images spanning portions of 4.8 Martian years, from September 1997 to November 2006.[32] The surveyor's cameras utilized 3 instruments: a narrow angle camera that took (black-and-white) high resolution images (usually 1.5 to 12 m per pixel) red and blue wide angle pictures for context (240 m per pixel) and daily global imaging (7.5 kilometres (4.7 mi) per pixel).[33]
Mars Pathfinder
The Soujourner rover on Mars
Main article: Mars Pathfinder

The Mars Pathfinder (MESUR Pathfinder,[34]) later renamed the Carl Sagan Memorial Station, was launched on December 4, 1996, just a month after the Mars Global Surveyor was launched. Onboard the lander was a small rover called Sojourner that would execute many experiments on the Martian surface. It was the second project from NASA's Discovery Program, which promotes the use of low-cost spacecraft and frequent launches under the motto "cheaper, faster and better" promoted by the then administrator, Daniel Goldin. The mission was directed by the Jet Propulsion Laboratory, a division of the California Institute of Technology, responsible for NASA's Mars Exploration Program.

This mission, besides being the first of a series of missions to Mars that included rovers (robotic exploration vehicles), was the most important since the Vikings landed on the red planet in 1976, and also was the first successful mission to send a rover to a planet. In addition to scientific objectives, the Mars Pathfinder mission was also a "proof-of-concept" for various technologies, such as airbag-mediated touchdown and automated obstacle avoidance, both later exploited by the Mars Exploration Rovers. The Mars Pathfinder was also remarkable for its extremely low price relative to other unmanned space missions to Mars.
Mars Exploration Rovers
Artist's conception of MER on Mars
Main article: Mars Exploration Rovers

NASA's Mars Exploration Rover Mission (MER), is an ongoing robotic space mission involving two rovers exploring the planet Mars. The mission is managed for NASA by the Jet Propulsion Laboratory, which designed, built and is operating the rovers.

The mission began in 2003 with the sending of the two rovers — MER-A Spirit and MER-B Opportunity — to explore the Martian surface and geology. The mission's scientific objective is to search for and characterize a wide range of rocks and soils that hold clues to past water activity on Mars. The mission is part of NASA's Mars Exploration Program which includes three previous successful landers: the two Viking program landers in 1976 and Mars Pathfinder probe in 1997.[35]

The total cost of building, launching, landing and operating the rovers on the surface for the initial 90-Martian-day (sol) primary mission was US$820 million.[36] Since the rovers have continued to function far beyond their initial 90 sol primary mission (to date both rovers have been functioning on Mars's surface for nearly seven years), they have each received multiple mission extensions.

In recognition of the vast amount of scientific information amassed by both rovers, two asteroids have been named in their honor: 37452 Spirit and 39382 Opportunity.
New Horizons probe
Artist's conception of New Horizons orbiting Pluto
Main article: New Horizons

New Horizons is a NASA robotic spacecraft mission currently en route to the dwarf planet Pluto. It is expected to be the first spacecraft to fly by and study Pluto and its moons, Charon, Nix, and Hydra. Once New Horizons leaves the Solar System, NASA may also approve flybys of one or more other Kuiper Belt Objects.

New Horizons was launched on January 19, 2006 directly into an Earth-and-solar-escape trajectory. It had an Earth-relative velocity of about 16.26 kilometres (10.10 mi)/s or 58,536 kilometres (36,373 mi)/h (10.10 mi/s or 36,373 mi/h) after its last engine shut down. Thus, it left Earth at the fastest launch speed ever recorded for a man-made object (although its specific orbital energy is less than that of Voyager 1, and the Helios Probes retain the maximum speed record for a spacecraft). New Horizons flew by Jupiter on February 28, 2007 and Saturn's orbit on June 8, 2008. It will arrive at Pluto on July 14, 2015 and then continue into the Kuiper belt.

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