Space exploration

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Space exploration is the physical exploration of outer-Earth objects and generally anything that involves the technologies, science, and politics regarding space endeavors.

It was given a boost by the launch of Sputnik 1, the first man-made object to orbit the Earth, which set off the space race between the United States and the Soviet Union. Two other famous achievements in the early days were putting the first man in space, Yuri Gagarin aboard Vostok 1, and the first people on the Moon, Neil Armstrong and Buzz Aldrin aboard Apollo 11. After 30 years of competition focus has started shifting from competition to cooperation and from one-off flights to renewable hardware and most recently to the building of extra-terrestrial launch platforms, such as from a space station and possibly from the Moon.


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Orbiting and reaching space

From a spaceflight perspective, the definition of space usually used is that space begins 100 km (62 miles) above Earth's surface. The United States sometimes uses a 50 mile definition. (See boundary to space.)

Achieving orbit is essential for going anywhere else, such as to the Moon or Mars. The first successful orbital launch was of the Soviet unmanned Sputnik I mission on October 4, 1957. This spectacular success led to an escalation of the American space program, and to an undeclared Space Race between the two superpowers. Soviet dog Laika became the first animal in orbit on November 3, 1957. The first orbital flight made by a human being was Vostok 1, carrying Yuri Gagarin on April 12, 1961.

One can distinguish the sub-orbital spaceflight and the orbital spaceflight (cf. Difference between sub-orbital and orbital spaceflights). As for sub-orbital flights, on October 3, 1942 an A4 rocket, a prototype for the German V2 rocket bomb, became the first successful launch of an object into space. The first organisms launched into space were fruit flies and corn seeds aboard a U.S.-launched V2 rocket in July, 1946. Another milestone was achieved on May 17, 2004 when Civilian Space eXploration Team launched the GoFast Rocket on a suborbital flight, the first amateur space flight. On June 21, 2004, SpaceShipOne became the first privately-funded manned spacecraft.

Space agencies

Brazilian Space Agency

The Brazilian Space Agency, founded in 1994, directs one of the youngest space programs. Brazil's space program is the most advanced in South America. It suffered a major setback in 2003 due to a rocket explosion that killed several technicians. They had their first success on October 23, 2004 with a VSV-30, or Brazilian Exploration Vehicle, launched on a sub-orbital mission. The agency's primary launch site is at Alcântara.

Canadian Space Agency

The Canadian Space Agency (CSA or, in French, the ASC) is the government department responsible for Canada's space program.

It was established in March 1989 by the Canadian Space Agency Act and sanctioned in December 1990. The agency is led by its president, who reports to the Minister of Industry.

China National Space Administration

The UN and PRC flags in orbit during the Shenzhou 5 mission.
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The UN and PRC flags in orbit during the Shenzhou 5 mission.

The China National Space Administration is the civilian agency in the People's Republic of China that is responsible for national space policy. The agency was created in 1993 when the Ministry of Aerospace Industry was split in two, with the other part being the China Aerospace Corp. China became only the third country on Earth to send a human into space independently on October 15, 2003 when Yang Liwei piloted the Shenzhou V mission, accomplishing 14 orbits before returning to Earth the next day.

In Oct 12, 2005 China sent its second spacecraft into space, the ShenZhou 6. The ShenZhou 6 carries 2 astronauts and it stayed in space for 5 days. The China National Space Administration agency allowed most television stations in China to broadcast the blast-off.

Indian Space Research Organisation

The Indian Space Research Organization, also known as ISRO, was established on August 15, 1969 under the Department of Atomic Energy of the Government of India. It manages all of India's space activities, and has a well developed space programme.

ISRO has capability to build and launch satellites up to 2000 kg into polar and geostationary orbit. It has 2 major satellite launch vehicles called PSLV (Polar satellite launch vehicle) and GSLV (Geostationary satellite Launch Vehicle). Most of ISRO's programs are geared towards nation building, though there are a few efforts in scientific research and space exploration. ISRO has started the work on its first Unmanned Lunar program called Chandrayan-1 (Moon-Ship-1) which is slated to be launched by 2007.

Japan Aerospace Exploration Agency

The Japan Aerospace eXploration Agency, or JAXA, is Japan's aerospace agency. It was formed October 1, 2003, by the merger of NASDA, the National Aerospace Laboratory of Japan and the Institute of Space and Aeronautical Science.

Space and Upper Atmosphere Research Commission (Pakistan)

See Suparco.

Russian Aviation and Space Agency

The Russian Aviation and Space Agency (RKA) (in Russian: Российское авиационно-космическое агентство) is the government agency responsible for Russia's space science program and general aerospace research. It was formed after the breakup of the Soviet Union and the dissolution of the Soviet space program.

National Space Agency of Ukraine

The National Space Agency of Ukraine (NSAU) is the Ukrainian government agency responsible for space policy and programs, established in 1992. It oversees Ukraine's national and commercial space research, construction, and launch programs. Launches are conducted in Kazakhstan, Russia, and on the Sea Launch platform.

National Aeronautics and Space Administration (United States)

In July 29, 1958, President Eisenhower signed the National Aeronautics and Space Act of 1958 establishing the National Aeronautics and Space Administration (NASA). When it began operations on October 1, 1958, NASA consisted mainly of the four laboratories and some 8,000 employees of the government's 46-year-old research agency for aeronautics, the National Advisory Committee for Aeronautics (NACA).

Criticisms

It is more expensive to perform certain tasks in space with humans rather than by robots or machines. Humans need large spacecraft that contain provisions such as a hermetic and temperature controlled cabin, production of breathable air, food and drink storage, waste disposal, voice- and other communication systems, and safety features such as crew escape systems, medical facilities, etc. There is also the question of the security of the spacecraft as whole; losing a robot is nowhere near as dramatic as human loss, so overall safety of non-human missions isn't as much of an issue. All of these extra expenses have to be weighed against the value of having humans aboard. Some critics argue that those few instances where human intervention are essential do not justify the enormous extra costs of having humans aboard.

Other critics, such as the physicist and Nobel-prize winner Richard Feynman, contend that space travel has never achieved any major scientific breakthroughs. However, others counter-argued that there have been many indirect scientific achievements: development of the modern computer, lasers, etc.

Some critics contend that in light of the huge distances in space, human space travel will never be able to do more than achieve an earth orbit or at best visit our closest neighbours in the solar system, and even this will consume large amounts of money and will require complex spacecraft that will accommodate only a handful of people. Supporters of human space travel state that this is irrelevant, because its real value lies in providing a focal point for national prestige and patriotism. They suggest that this was the reason why the Clinton administration cooperated closely with Russia on the International Space Station: it gave Russia something to take pride in, and as such became a stabilizing factor in post-communist Russia. From this point of view, the ISS was a justifyable cash outlay.

Some people also have moral objections to the huge costs of space travel, and point out that even a fraction of the space travel budget would make a huge difference in fighting disease and hunger in the world. However, space exploration itself receives a very small percentage of total government spending (nearly always under 0.5%).

Overall, the public remains largely supportive of both manned and unmanned space exploration. According to an Associated Press Poll conducted in July 2003, 71% of US citizens agreed with the statement that the space program is "a good investment," compared to 21% who did not (Pollingreport.com).

Timeline of Space Exploration

1957-1975

Date First Success Country Mission Name
1946 Animal in space (fruit flies)  USA-ABMA V2
August 21, 1957 ICBM  USSR R-7/SS-6 Sapwood
October 4, 1957 Artificial satellite  USSR Sputnik 1
November 3, 1957 Animal in orbit (dog)  USSR Sputnik 2
January 31, 1958 Detection of Van Allen belts  USA-ABMA Explorer I
December 18, 1958 Communications satellite  USA-ABMA Project SCORE
September 14, 1959 Probe to Moon  USSR Luna 2
February 17, 1959 Weather satellite  USA-NASA (NRL)1 Vanguard 2
August 7, 1959 Photo of Earth from space  USA-NASA Explorer 6
August 18, 1960 Reconnaissance satellite  USA-Air Force KH-1 9009
April 12, 1961 Human in orbit  USSR Vostok 1
March 18, 1965 Extra-vehicular activity  USSR Voskhod 2
December 15, 1965 Orbital rendezvous2  USA-NASA Gemini 6A/Gemini 7
March 1, 1966 Probe to another planet  USSR Venera 3
July 21, 1969 Human on the Moon  USA-NASA Apollo 11
April 23, 1971 Space station  USSR Salyut 1
July 15, 1975 First U.S.-USSR joint mission  USSR  USA-NASA Apollo-Soyuz Test Project

1Project Vanguard was transferred from the NRL to NASA immediately before launch.
2 The Soviet Union had attempted an earlier rendezvous on August 12, 1962; However, Vostok 3 and Vostok 4 were only within five kilometers of one another, and were in different orbital planes. Pravda, however, did not mention this information and indicated that rendezvous had been accomplished.

post-1975

Date First Success Country Mission Name
October 2, 1978 Non-American and non-Soviet in space  USSR Soyuz 28
April 12, 1981 Reusable manned spacecraft  USA-NASA STS-1
June 13, 1983 Extra-solar system spacecraft  USA-NASA Pioneer 10
September 11, 1985 Comet probe  USA-NASA International Cometary Explorer
April 28, 2001 Space tourist  Russia  USA Soyuz TM-32
June 21, 2004 Privately developed manned spacecraft  USA-MAV SpaceShipOne 15P

Reusable spacecraft

The Space Shuttle Columbia seconds after engine ignition, 12 April 1981 (NASA)
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The Space Shuttle Columbia seconds after engine ignition, 12 April 1981 (NASA)

The first reusable spacecraft, the Space Shuttle, was launched by the USA on the 20th anniversary of Yuri Gagarin's flight, on April 12, 1981. During the Shuttle era, six orbiters were built, all of which have flown in the atmosphere and five of which have flown in space. The Enterprise was used only for approach and landing tests, launching from the back of a Boeing 747 and gliding to deadstick landings at Edwards AFB, California. The first Space Shuttle to fly into space was the Columbia, followed by the Challenger, Discovery, Atlantis, and Endeavour. The Endeavour was built to replace the Challenger when it was lost in January 1986. The Columbia broke up during reentry in February 2003.

The first (and so far only) automatic reusable spacecraft was the Buran (Snowstorm), launched by the USSR on November 15, 1988, although it made only one flight. This spaceplane was designed for a crew and strongly resembled the U.S. Space Shuttle, although its drop-off boosters used liquid propellants and its main engines were located at the base of what would be the external tank in the American Shuttle. Lack of funding, complicated by the dissolution of the USSR, prevented any further flights of Buran.

The Space Shuttle is due to be retired by 2010, and due to be replaced by the Crewed Exploration Vehicle which may be itself be reusable. However, complex reusable spaceplanes are hard to justify next to cheaper and safer expendable rockets.

See also

Commons
Wikimedia Commons has media related to:

Unmanned missions

Main article: Unmanned space missions

Animals in space

Humans in space

Main articles: Astronauts and human spaceflight

Recent and future developments

Other

External link


 
National Space Programmes
Human spaceflight : USSR / Russia | United States | China (PRC)
Brazil | Canada | Europe ( France, Germany, Italy) | Japan | India | South Korea | Taiwan (ROC) | Ukraine

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