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Space Manufacturing
Space manufacturing is the production of tangible goods beyond Earth. Since most production capabilities are limited to low Earth orbit, the term in-orbit manufacturing is also frequently used. There are several rationales supporting in-space manufacturing: * The space environment, in particular the effects of microgravity and vacuum, enable the research of and production of goods that could otherwise not be manufactured on Earth. * The extraction and processing of raw materials from other astronomical bodies, also called In-Situ Resource Utilisation (ISRU) could enable more sustainable space exploration missions at reduced cost compared to launching all required resources from Earth. * Raw materials could be transported to low Earth orbit where they could be processed into goods that are shipped to Earth. By replacing terrestrial production on Earth, this seeks to preserve the Earth. * Raw materials of very high value, for example gold, silver, or platinum, could be transpor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Future Moon Base
The future is the time after the past and present. Its arrival is considered inevitable due to the existence of time and the laws of physics. Due to the apparent nature of reality and the unavoidability of the future, everything that currently exists and will exist can be categorized as either permanent, meaning that it will exist forever, or temporary, meaning that it will end. In the Occidental view, which uses a linear conception of time, the future is the portion of the projected timeline that is anticipated to occur. In special relativity, the future is considered absolute future, or the future light cone. In the philosophy of time, presentism is the belief that only the present exists and the future and the past are unreal. Religions consider the future when they address issues such as karma, life after death, and eschatologies that study what the end of time and the end of the world will be. Religious figures such as prophets and diviners have claimed to see into ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crystal
A crystal or crystalline solid is a solid material whose constituents (such as atoms, molecules, or ions) are arranged in a highly ordered microscopic structure, forming a crystal lattice that extends in all directions. In addition, macroscopic single crystals are usually identifiable by their geometrical shape, consisting of flat faces with specific, characteristic orientations. The scientific study of crystals and crystal formation is known as crystallography. The process of crystal formation via mechanisms of crystal growth is called crystallization or solidification. The word ''crystal'' derives from the Ancient Greek word (), meaning both "ice" and "rock crystal", from (), "icy cold, frost". Examples of large crystals include snowflakes, diamonds, and table salt. Most inorganic solids are not crystals but polycrystals, i.e. many microscopic crystals fused together into a single solid. Polycrystals include most metals, rocks, ceramics, and ice. A third category ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Foton-M2
Foton-M No.2 was an unmanned Foton-M spacecraft which carried a European payload for the European Space Agency (ESA). It was placed into orbit by a Russian Soyuz-U rocket launched at 12:00 UTC on 20 June 2005 from the Baikonur Cosmodrome in Kazakhstan by the Russian Space Agency (RKA). The Foton-M No.2 mission was a replacement for the failed Foton-M No.1 mission, which was lost in a launch failure on 15 October 2002. The payload carried by the spacecraft included of experiments; consisting of 39 experiments in fluid physics, biology, material science, meteoritics, radiation dosimetry and exobiology ( BIOPAN-5). Some of the experiments were designed by the ESA's student programme. One notable experiment tested the ability of lichen to survive in space. It was successful, as the lichen survived over 14 days of exposure to space. References External links ESA [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gallium Arsenide
Gallium arsenide (GaAs) is a III-V direct band gap semiconductor with a zinc blende crystal structure. Gallium arsenide is used in the manufacture of devices such as microwave frequency integrated circuits, monolithic microwave integrated circuits, infrared light-emitting diodes, laser diodes, solar cells and optical windows. GaAs is often used as a substrate material for the epitaxial growth of other III-V semiconductors, including indium gallium arsenide, aluminum gallium arsenide and others. Preparation and chemistry In the compound, gallium has a +3 oxidation state. Gallium arsenide single crystals can be prepared by three industrial processes: * The vertical gradient freeze (VGF) process. * Crystal growth using a horizontal zone furnace in the Bridgman-Stockbarger technique, in which gallium and arsenic vapors react, and free molecules deposit on a seed crystal at the cooler end of the furnace. * Liquid encapsulated Czochralski (LEC) growth is used for producing hi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wake Shield Facility
Wake Shield Facility (WSF) was a NASA experimental science platform that was placed in low Earth orbit by the Space Shuttle. It was a diameter, free-flying stainless steel disk. The WSF was deployed using the Space Shuttle's Canadarm. The WSF then used nitrogen gas thrusters to position itself about behind the Space Shuttle, which was at an orbital altitude of over , within the thermosphere, where the atmosphere is exceedingly tenuous. The WSF's orbital speed was at least three to four times faster than the speed of thermospheric gas molecules in the area, which resulted in a cone behind the WSF that was entirely free of gas molecules. The WSF thus created an ultrahigh vacuum in its wake. The resulting vacuum was used to study epitaxial film growth. The WSF operated at a distance from the Space Shuttle to avoid contamination from the Shuttle's rocket thrusters and water dumped overboard from the Shuttle's Waste Collection System (space toilet). After two days, the Space Shu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wake Shield Facility
Wake Shield Facility (WSF) was a NASA experimental science platform that was placed in low Earth orbit by the Space Shuttle. It was a diameter, free-flying stainless steel disk. The WSF was deployed using the Space Shuttle's Canadarm. The WSF then used nitrogen gas thrusters to position itself about behind the Space Shuttle, which was at an orbital altitude of over , within the thermosphere, where the atmosphere is exceedingly tenuous. The WSF's orbital speed was at least three to four times faster than the speed of thermospheric gas molecules in the area, which resulted in a cone behind the WSF that was entirely free of gas molecules. The WSF thus created an ultrahigh vacuum in its wake. The resulting vacuum was used to study epitaxial film growth. The WSF operated at a distance from the Space Shuttle to avoid contamination from the Shuttle's rocket thrusters and water dumped overboard from the Shuttle's Waste Collection System (space toilet). After two days, the Space Shu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
International Space Station
The International Space Station (ISS) is the largest modular space station currently in low Earth orbit. It is a multinational collaborative project involving five participating space agencies: NASA (United States), Roscosmos (Russia), JAXA (Japan), ESA (Europe), and CSA (Canada). The ownership and use of the space station is established by intergovernmental treaties and agreements. The station serves as a microgravity and space environment research laboratory in which scientific research is conducted in astrobiology, astronomy, meteorology, physics, and other fields. The ISS is suited for testing the spacecraft systems and equipment required for possible future long-duration missions to the Moon and Mars. The ISS programme evolved from the Space Station ''Freedom'', a 1984 American proposal to construct a permanently crewed Earth-orbiting station, and the contemporaneous Soviet/Russian '' Mir-2'' proposal from 1976 with similar aims. The ISS is the ninth space station to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Space Shuttle
The Space Shuttle is a retired, partially reusable low Earth orbital spacecraft system operated from 1981 to 2011 by the U.S. National Aeronautics and Space Administration (NASA) as part of the Space Shuttle program. Its official program name was Space Transportation System (STS), taken from a 1969 plan for a system of reusable spacecraft where it was the only item funded for development. The first ( STS-1) of four orbital test flights occurred in 1981, leading to operational flights (STS-5) beginning in 1982. Five complete Space Shuttle orbiter vehicles were built and flown on a total of 135 missions from 1981 to 2011. They launched from the Kennedy Space Center (KSC) in Florida. Operational missions launched numerous satellites, interplanetary probes, and the Hubble Space Telescope (HST), conducted science experiments in orbit, participated in the Shuttle-''Mir'' program with Russia, and participated in construction and servicing of the International Space Station (IS ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spacelab
Spacelab was a reusable laboratory developed by European Space Agency (ESA) and used on certain spaceflights flown by the Space Shuttle. The laboratory comprised multiple components, including a pressurized module, an unpressurized carrier, and other related hardware housed in the Shuttle's cargo bay. The components were arranged in various configurations to meet the needs of each spaceflight. Spacelab components flew on a total of about 32 Shuttle missions, depending on how such hardware and missions are tabulated. Spacelab allowed scientists to perform experiments in micro-g environment , microgravity in geocentric orbit. There was a variety of Spacelab-associated hardware, so a distinction can be made between the major Spacelab program missions with European scientists running missions in the Spacelab habitable module, missions running other Spacelab hardware experiments, and other Space Transportation System (STS) missions that used some component of Spacelab hardware. Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Space Studies Institute
Space Studies Institute is a not-for-profit organization that was founded in 1977 by Princeton University Professor Gerard K. O'Neill. In 2009 SSI moved its operations from its long-term base in Princeton, New Jersey, to Mojave, California. SSI is involved in several initiatives, including a solar sail project that it is developing with Carnegie Mellon University and an effort to find asteroids that could be mined for valuable materials. The use of extraterrestrial resources in space settlement has received increasing attention in recent years. The Institute has sponsored research studies on several transport systems for the development of space. Their first program was in the development of prototype mass driver systems. They are also studying the use of an ''Orbital Transfer Vehicle'' as a component of space manufacturing. Other areas of research include a search for Earth-Sun Trojan asteroids, a design study of a ''Lunar Polar Probe'' to search for water and useful v ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Molten
Melting, or fusion, is a physical process that results in the phase transition of a substance from a solid to a liquid. This occurs when the internal energy of the solid increases, typically by the application of heat or pressure, which increases the substance's temperature to the melting point. At the melting point, the ordering of ions or molecules in the solid breaks down to a less ordered state, and the solid "melts" to become a liquid. Substances in the molten state generally have reduced viscosity as the temperature increases. An exception to this principle is the element sulfur, whose viscosity increases in the range of 160 °C to 180 °C due to polymerization. Some organic compounds melt through mesophases, states of partial order between solid and liquid. First order phase transition From a thermodynamics point of view, at the melting point the change in Gibbs free energy ''∆G'' of the substances is zero, but there are non-zero changes in the enthal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electron Beam Welding
Electron-beam welding (EBW) is a fusion welding process in which a beam of high-velocity electrons is applied to two materials to be joined. The workpieces melt and flow together as the kinetic energy of the electrons is transformed into heat upon impact. EBW is often performed under vacuum conditions to prevent dissipation of the electron beam. History Electron-beam welding was developed by the German physicist Karl-Heinz Steigerwald in 1949, who was at the time working on various electron-beam applications. Steigerwald conceived and developed the first practical electron-beam welding machine, which began operation in 1958. American inventor James T. Russell has also been credited with designing and building the first electron-beam welder. Physics of electron-beam heating Electrons are elementary particles possessing a mass ''m'' = 9.1 · 10−31 kg and a negative electrical charge ''e'' = 1.6 · 10−19 C. They exist either bound to an a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
