Daily Archives: December 20, 2013

A space station (or orbital station) is a spacecraft capable of supporting a crew, which is designed to remain in space (most commonly in low Earth orbit) for an extended period of time and for other spacecraft to dock. A space station is distinguished from other spacecraft used for human spaceflight by lack of major propulsion or landing systems. Instead, other vehicles transport people and cargo to and from the station. As of November 2012[update] two space stations are in orbit: the International Space Station, which is permanently manned, and China's Tiangong 1 (which successfully launched on September 29, 2011, after its launch was delayed from August), which is unmanned most of the time.[1][2] Previous stations include the Almaz and Salyut series, Skylab and most recently Mir.

Today's space stations are research platforms, used to study the effects of long-term space flight on the human body as well as to provide platforms for greater number and length of scientific studies than available on other space vehicles. All space stations to date have been designed with the intention of rotating multiple crews, with each crew member staying aboard the station for weeks or months, but rarely more than a year. Since the ill-fated flight of Soyuz 11 to Salyut 1, all manned spaceflight duration records have been set aboard space stations. The duration record for a single spaceflight is 437.7 days, set by Valeriy Polyakov aboard Mir from 1994 to 1995. As of 2013[update], three astronauts have completed single missions of over a year, all aboard Mir.

Space stations have also been used for both military and civilian purposes. The last military-use space station was Salyut 5, which was used by the Almaz program of the Soviet Union in 1976 and 1977.[3]

Space stations have been envisaged since at least as early as 1869 when Edward Everett Hale wrote "The Brick Moon".[4] The first to give serious consideration to space stations were Konstantin Tsiolkovsky in the early 20th century and Hermann Oberth about two decades later.[4] In 1929 Herman Potonik's The Problem of Space Travel was published, the first to envision a "rotating wheel" space station to create artificial gravity.

During the Second World War, German scientists researched the theoretical concept of an orbital weapon based on a space station. Pursuing Oberth's idea of a space-based weapon, the so-called "sun gun" was a concept of a space station orbiting Earth at a height of 5,100 miles (8,200km), with a weapon that was to utilize the sun's energy.[5]

In 1951, in Collier's weekly, Wernher von Braun published his design for a wheel-shaped space station, which referenced the "rotating wheel" idea first proclaimed Potonik however these concepts would never leave the concept stage during the 20th century.[4]

During the same time as von Braun pursued Potonik's ideas, the Soviet design bureaus chiefly Vladimir Chelomey's OKB-52 were pursuing Tsiolkovsky's ideas for space stations. The work by OKB-52 would lead to the Almaz programme and (together with OKB-1) to the first space station: Salyut 1. The developed hardware laid the ground for the Salyut and Mir space stations, and is even today a considerable part of the ISS space station.

The first space station was Salyut 1, which was launched by the Soviet Union on April 19, 1971. Like all the early space stations, it was "monolithic", intended to be constructed and launched in one piece, and then manned by a crew later. As such, monolithic stations generally contained all their supplies and experimental equipment when launched, and were considered "expended", and then abandoned, when these were used up.

The earlier Soviet stations were all designated "Salyut", but among these there were two distinct types: civilian and military. The military stations, Salyut 2, Salyut 3, and Salyut 5, were also known as Almaz stations.

The civilian stations Salyut 6 and Salyut 7 were built with two docking ports, which allowed a second crew to visit, bringing a new spacecraft with them; the Soyuz ferry could spend 90 days in space, after which point it needed to be replaced by a fresh Soyuz spacecraft.[6] This allowed for a crew to man the station continually. Skylab was also equipped with two docking ports, like second-generation stations, but the extra port was never utilized. The presence of a second port on the new stations allowed Progress supply vehicles to be docked to the station, meaning that fresh supplies could be brought to aid long-duration missions. This concept was expanded on Salyut 7, which "hard docked" with a TKS tug shortly before it was abandoned; this served as a proof-of-concept for the use of modular space stations. The later Salyuts may reasonably be seen as a transition between the two groups.

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Space station - Wikipedia, the free encyclopedia

International Space Station The International Space Station, as seen from Space Shuttle Endeavour in May 2011. ISS insignia Station statistics COSPAR ID 1998-067A Call sign Alpha Crew Fully crewed 6 Currently aboard 6 (Expedition 38) Launch 19982020 Launch pad Baikonur 1/5 and 81/23 Kennedy LC-39 Mass approximately 450,000kg (990,000lb) Length 72.8m (239ft) Width 108.5m (356ft) Height c. 20m (c. 66ft) nadirzenith, arrays forwardaft (27 November 2009)[dated info] Pressurised volume 837m3 (29,600cuft) (21 March 2011) Atmospheric pressure 101.3kPa (29.91inHg, 1 atm) Perigee 414km (257mi) AMSL[1] Apogee 421km (262mi) AMSL[1] Orbital inclination 51.65degrees[1] Average speed 7.66 kilometres per second (27,600km/h; 17,100mph)[1] Orbital period 92.92minutes[1] Orbit epoch 14 December 2013[1] Days in orbit 5509 (20 December) Days occupied 4796 (20 December) Number of orbits 86,263[1] Orbital decay 2km/month Statistics as of 9 March 2011 (unless noted otherwise) References: [1][2][3][4][5][6] Configuration Station elements as of December 2011[update], but missing Pirs (exploded view)

The International Space Station (ISS) is a space station, or a habitable artificial satellite in low Earth orbit. The ninth space station to be inhabited by crews, it follows the Soviet and later Russian Salyut, Almaz, and Mir stations, and Skylab from the U.S. The ISS is a modular structure whose first component was launched in 1998.[7] Now the largest artificial body in orbit, it can often be seen at the appropriate time with the naked eye from Earth.[8] The ISS consists of pressurised modules, external trusses, solar arrays and other components. ISS components have been launched by American Space Shuttles as well as Russian Proton and Soyuz rockets.[9] Budget constraints led to the merger of three space station projects with the Japanese Kib module and Canadian robotics. In 1993 the partially built components for a Soviet/Russian space station Mir-2, the proposed American Freedom, and the proposed European Columbus merged into a single multinational programme.[9] The ISS is arguably the most expensive single item ever constructed.[10]

The ISS serves as a microgravity and space environment research laboratory in which crew members conduct experiments in biology, human biology, physics, astronomy, meteorology and other fields.[11][12][13] The station is suited for the testing of spacecraft systems and equipment required for missions to the Moon and Mars.[14]

Since the arrival of Expedition 1 on 2 November 2000, the station has been continuously occupied for 700113000000000000013years and 700148000000000000048days, the longest continuous human presence in space. (In 2010, the station surpassed the previous record of almost 10 years (or 3,634 days) held by Mir.) The station is serviced by a variety of visiting spacecraft: Soyuz, Progress, the Automated Transfer Vehicle, the H-II Transfer Vehicle,[15]Dragon, and Cygnus. It has been visited by astronauts and cosmonauts from 15 different nations.[16]

The ISS programme is a joint project among five participating space agencies: NASA, Roskosmos, JAXA, ESA, and CSA.[15][17] The ownership and use of the space station is established by intergovernmental treaties and agreements.[18] The station is divided into two sections, the Russian Orbital Segment (ROS) and the United States Orbital Segment (USOS), which is shared by many nations. The ISS maintains an orbit with an altitude of between 330km (205mi) and 435km (270mi) by means of reboost manoeuvres using the engines of the Zvezda module or visiting spacecraft. It completes 15.50orbits per day.[19] The ISS is funded until 2020, and may operate until 2028.[20][21][22] The Russian Federal Space Agency, Roskosmos (RKA) has proposed using the ISS to commission modules for a new space station, called OPSEK, before the remainder of the ISS is deorbited.

According to the original Memorandum of Understanding between NASA and Rosaviakosmos, the International Space Station was intended to be a laboratory, observatory and factory in space. It was also planned to provide transportation, maintenance, and act as a staging base for possible future missions to the Moon, Mars and asteroids.[23] In the 2010 United States National Space Policy, the ISS was given additional roles of serving commercial, diplomatic[24] and educational purposes.[25]

The ISS provides a platform to conduct scientific research that cannot be performed in any other way. While small unmanned spacecraft can provide platforms for zero gravity and exposure to space, space stations offer a long term environment where studies can be performed potentially for decades, combined with ready access by human researchers over periods that exceed the capabilities of manned spacecraft.[16][26]

The Station simplifies individual experiments by eliminating the need for separate rocket launches and research staff. The primary fields of research include Astrobiology, astronomy, human research including space medicine and life sciences, physical sciences, materials science, space weather and weather on Earth (meteorology).[11][12][13][27][28] Scientists on Earth have access to the crew's data and can modify experiments or launch new ones, benefits generally unavailable on unmanned spacecraft.[26] Crews fly expeditions of several months duration, providing approximately 160 man-hours a week of labour with a crew of 6.[11][29]

Kib is intended to accelerate Japan's progress in science and technology, gain new knowledge and apply it to such fields as industry and medicine.[30]

In order to detect dark matter and answer other fundamental questions about our universe, engineers and scientists from all over the world built the Alpha Magnetic Spectrometer (AMS), which NASA compares to the Hubble telescope, and says could not be accommodated on a free flying satellite platform due in part to its power requirements and data bandwidth needs.[31][32] On 3 April 2013, NASA scientists reported that hints of dark matter may have been detected by the Alpha Magnetic Spectrometer.[33][34][35][36][37][38] According to the scientists, "The first results from the space-borne Alpha Magnetic Spectrometer confirm an unexplained excess of high-energy positrons in Earth-bound cosmic rays."

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International Space Station - Wikipedia, the free encyclopedia

Space station updates have moved.

Please go to the Space Station page on the NASA Web for continuing international space station coverage.

Space travelers living on Mars for extended periods will need to grow plants, which provide food and generate oxygen. But the decreased gravity and low atmospheric pressure environment will stress the plants and make them hard to grow.

Greenhouses in the Station's Destiny Laboratory and in the Zvezda Service Module grow plants in a controlled environment. Station crews tend the plants, photograph them and harvest samples for return to Earth. Researchers can use the resulting data to develop new techniques for successfully growing plants in space.

NASA is also concerned about health hazards posed by space radiation. A spacecraft bound for Mars will be exposed to substantial amounts of radiation, and it will have to protect the humans inside from exposure.

On the station, sensors inside the crew areas monitor radiation levels. NASA scientists, who have maintained radiation data since the beginning of human space flight, continue to learn about the dangers it poses. Researchers use the station to test materials that could be used for Mars-bound spacecraft.

Will it ever be safe for humans to live on Mars? Researchers are learning more every day, thanks to the results of ISS experiments.

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HSF - International Space Station

Astronauts aboard the International Space Station are now scheduled to conduct three spacewalks to replace a malfunctioning coolant pump on the station's exterior.

Three spacewalks over five days, with a final outing Christmas Day that ties the bow on a badly needed space-station repair job?

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This might not have been the way NASA astronauts Rick Mastracchio and Air Force Col. Mike Hopkins originally planned to spend Christmas. But that's the schedule they face now that the agency has decided to replace a malfunctioning coolant pump on the station's exterior.

Mission managers made the call on Tuesday afternoon, determining that it was more prudent to replace the pump with one of three spare units the station carries than continue pursuing a work-around engineers had devised for bringing the pump back into full service.

The pump sends ammonia through one of two external cooling loops designed to remove heat from the station's interior as well as from equipment on the station's exterior.

On Dec. 11, ground controllers noticed that the fluid was too cool. Temperatures were sufficient to continue cooling equipment outside the station's modules. But the ammonia also circulates through a heat exchanger inside the station, accepting the excess heat from a water-based loop that keeps hardware, labs, and living spaces in the station cool.

Engineers isolated the problem to a flow-control valve used to regulate the ammonia's temperature and devised a way to use a different valve to do the job.

"The engineering teams did just an amazing job of sorting through all kinds of options to try to recover the valve and look at other ways to manage the flow," said Michael Suffredini, the International Space Station program manager.

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Christmas Day spacewalk? Astronauts will go outside to fix space station. (+video)

Astronauts aboard the International Space Station are now scheduled to conduct three spacewalks to replace a malfunctioning coolant pump on the station's exterior.

Three spacewalks over five days, with a final outing Christmas Day that ties the bow on a badly needed space-station repair job?

Subscribe Today to the Monitor

Click Here for your FREE 30 DAYS of The Christian Science Monitor Weekly Digital Edition

This might not have been the way NASA astronauts Rick Mastracchio and Air Force Col. Mike Hopkins originally planned to spend Christmas. But that's the schedule they face now that the agency has decided to replace a malfunctioning coolant pump on the station's exterior.

Mission managers made the call on Tuesday afternoon, determining that it was more prudent to replace the pump with one of three spare units the station carries than continue pursuing a work-around engineers had devised for bringing the pump back into full service.

The pump sends ammonia through one of two external cooling loops designed to remove heat from the station's interior as well as from equipment on the station's exterior.

On Dec. 11, ground controllers noticed that the fluid was too cool. Temperatures were sufficient to continue cooling equipment outside the station's modules. But the ammonia also circulates through a heat exchanger inside the station, accepting the excess heat from a water-based loop that keeps hardware, labs, and living spaces in the station cool.

Engineers isolated the problem to a flow-control valve used to regulate the ammonia's temperature and devised a way to use a different valve to do the job.

"The engineering teams did just an amazing job of sorting through all kinds of options to try to recover the valve and look at other ways to manage the flow," said Michael Suffredini, the International Space Station program manager.

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Christmas Day spacewalk? Astronauts will go outside to fix space station.