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RORSAT
Upravlyaemy Sputnik Aktivnyy (russian: Управляемый Спутник Активный for Controlled Active Satellite), or US-A, also known in the west as Radar Ocean Reconnaissance Satellite or RORSAT (GRAU index 17F16K), was a series of 33 Soviet reconnaissance satellites. Launched between 1967 and 1988 to monitor NATO and merchant vessels using radar, the satellites were powered by nuclear reactors. Because a return signal from an ordinary target illuminated by a radar transmitter diminishes as the inverse of the fourth power of the distance, for the surveillance radar to work effectively, US-A satellites had to be placed in low Earth orbit. Had they used large solar panels for power, the orbit would have rapidly decayed due to drag through the upper atmosphere. Further, the satellite would have been useless in the shadow of Earth. Hence the majority of the satellites carried type BES-5 nuclear reactors fuelled by uranium-235. Normally the nuclear reactor cores were e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
RORSAT By Ronald C
Upravlyaemy Sputnik Aktivnyy (russian: Управляемый Спутник Активный for Controlled Active Satellite), or US-A, also known in the west as Radar Ocean Reconnaissance Satellite or RORSAT (GRAU index 17F16K), was a series of 33 Soviet reconnaissance satellites. Launched between 1967 and 1988 to monitor NATO and merchant vessels using radar, the satellites were powered by nuclear reactors. Because a return signal from an ordinary target illuminated by a radar transmitter diminishes as the inverse of the fourth power of the distance, for the surveillance radar to work effectively, US-A satellites had to be placed in low Earth orbit. Had they used large solar panels for power, the orbit would have rapidly decayed due to drag through the upper atmosphere. Further, the satellite would have been useless in the shadow of Earth. Hence the majority of the satellites carried type BES-5 nuclear reactors fuelled by uranium-235. Normally the nuclear reactor cores were ej ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Space Debris
Space debris (also known as space junk, space pollution, space waste, space trash, or space garbage) are defunct human-made objects in space—principally in Earth orbit—which no longer serve a useful function. These include derelict spacecraft—nonfunctional spacecraft and abandoned launch vehicle stages—mission-related debris, and particularly numerous in Earth orbit, fragmentation debris from the breakup of derelict rocket bodies and spacecraft. In addition to derelict human-made objects left in orbit, other examples of space debris include fragments from their disintegration, erosion and collisions or even paint flecks, solidified liquids expelled from spacecraft, and unburned particles from solid rocket motors. Space debris represents a risk to spacecraft. Space debris is typically a negative externality—it creates an external cost on others from the initial action to launch or use a spacecraft in near-Earth orbit—a cost that is typically not taken into account ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kosmos 1402
Kosmos 1402 (russian: Космос 1402) was a Soviet spy satellite that malfunctioned, resulting in the uncontrolled re-entry of its nuclear reactor and its radioactive uranium fuel. Kosmos 1402 was launched on August 30, 1982, and re-entered the atmosphere on 23 January 1983. The fission reactor entered a few days later; on 7 February 1983. Kosmos 1402 was a RORSAT surveillance satellite that used radar for monitoring NATO vessels. The power source for the satellite was a BES-5 nuclear fission reactor, which used about of enriched uranium as a fuel source. The satellite operated in low Earth orbit, and the reactor was designed to eject to a higher parking orbit at the end of the satellite's mission, or in the event of a mishap. This ejection mechanism was implemented in the RORSAT satellites after a nuclear accident caused by a previous malfunction of Kosmos 954, five years earlier over Canada's Northwest Territories. In response to the Kosmos 954 mishap, RORSAT satellites we ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kosmos 954
Kosmos 954 (russian: Космос 954) was a reconnaissance satellite launched by the Soviet Union in 1977. A malfunction prevented safe separation of its onboard nuclear reactor; when the satellite reentered the Earth's atmosphere the following year, it scattered radioactive debris over northern Canada, some of the debris landing in the Great Slave Lake next to Fort Resolution, NWT. This prompted an extensive multiyear cleanup operation known as Operation Morning Light, which the Canadian government billed the Soviet Union for over Can$6 million, and for which the USSR eventually paid just Can$3 million in compensation. Launch and operation The satellite was part of the Soviet Union's RORSAT programme, a series of reconnaissance satellites which observed ocean traffic, including surface vessels and nuclear submarines, using active radar. It was assigned the Kosmos number 954 and was launched on 18 September 1977 at 13:55 UTC from the Baikonur Cosmodrome, on a Tsyklon-2 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kosmos 1867
Kosmos 1867 (russian: Космос 1867) is a nuclear powered radar ocean reconnaissance satellite (RORSAT) that was launched by the Soviet Union on July 10, 1987. It was put into an orbit of about . Its mission was to monitor the oceans for naval and merchant vessels, and had a mission life of about eleven months. Description Kosmos 1867 was launched on July 10, 1987, on a Tsyklon-2 rocket from the Baikonur Cosmodrome. It was put into an orbit about above the Earth's surface at an inclination of 65° and a period of 100.8 minutes. The satellite had a mission life of about 11 months. The satellite was powered by TOPAZ 1 nuclear reactor. This reactor was cooled by liquid sodium-potassium (NaK) metal, and used a high-temperature moderator containing hydrogen and highly enriched fuel. The reactor produced electricity using a thermionic converter. The satellite used a ''Plazma-2 SPT'' Hall-effect thruster for propulsion. The mission of Kosmos 1867 was to search the oceans for nav ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
BES-5
BES-5, also known as Bouk or Buk (russian: бук, translation=beech), was a Soviet thermoelectric generator that was used to power 31 satellites in the US-A (RORSAT) project. The heat source was a uranium 235 fast fission nuclear reactor (FNR). Background Spacecraft nuclear reactors are typically fast reactors for the following reasons. First, normal moderator materials (carbon, water) add bulk and mass which is not desirable in a spacecraft. Second, for reasons of nucleonics the fuel must be highly enriched to have a lightweight critical mass (similar to small reactor designs on nuclear submarines). Note that some of the 238U (which is fertile and not fissile) will be converted to 239Pu during operation, and this is taken into consideration during the design and while estimating the power output and design life expectancy. Reactor design The design of the BES-5 FNR is such that a sub-critical assembly exists into which a rod of fissile material is inserted. Feedback and mo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kosmos 1818
Kosmos 1818 was a nuclear powered Soviet surveillance satellite in the RORSAT program, which monitored NATO vessels using radar. Kosmos 1818 was the first satellite to use the TOPAZ-1 fission reactor. In July 2008, the satellite was damaged, and leaked a trail of sodium coolant. Description Kosmos 1818 was launched on February 1, 1987 on a Tsyklon-2 rocket from the Baikonur Cosmodrome. It was put into an orbit about above the Earth's surface at an inclination of 65° and a period of 100.6 minutes. The satellite had a mission life of about five to six months. The satellite was powered by a TOPAZ nuclear reactor, TOPAZ 1 nuclear reactor. This was cooled by liquid sodium-potassium, NaK, metal, it used a high-temperature Neutron moderator, moderator containing hydrogen and highly enriched uranium fuel. It produced electricity using a thermionic converter. It had a Hall effect thruster, Plazma-2 SPT electric engine. Its mission was to search the oceans for naval and merchant ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nuclear Power In Space
Nuclear power in space is the use of nuclear power in outer space, typically either small fission systems or radioactive decay for electricity or heat. Another use is for scientific observation, as in a Mössbauer spectrometer. The most common type is a radioisotope thermoelectric generator, which has been used on many space probes and on crewed lunar missions. Small fission reactors for Earth observation satellites, such as the TOPAZ nuclear reactor, have also been flown. A radioisotope heater unit is powered by radioactive decay and can keep components from becoming too cold to function, potentially over a span of decades. The United States tested the SNAP-10A nuclear reactor in space for 43 days in 1965, with the next test of a nuclear reactor power system intended for space use occurring on 13 September 2012 with the Demonstration Using Flattop Fission (DUFF) test of the Kilopower reactor. After a ground-based test of the experimental 1965 Romashka reactor, which used u ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nuclear Reactor
A nuclear reactor is a device used to initiate and control a fission nuclear chain reaction or nuclear fusion reactions. Nuclear reactors are used at nuclear power plants for electricity generation and in nuclear marine propulsion. Heat from nuclear fission is passed to a working fluid (water or gas), which in turn runs through steam turbines. These either drive a ship's propellers or turn electrical generators' shafts. Nuclear generated steam in principle can be used for industrial process heat or for district heating. Some reactors are used to produce isotopes for medical and industrial use, or for production of weapons-grade plutonium. , the International Atomic Energy Agency reports there are 422 nuclear power reactors and 223 nuclear research reactors in operation around the world. In the early era of nuclear reactors (1940s), a reactor was known as a nuclear pile or atomic pile (so-called because the graphite moderator blocks of the first reactor were placed in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radioisotope Thermoelectric Generator
A radioisotope thermoelectric generator (RTG, RITEG), sometimes referred to as a radioisotope power system (RPS), is a type of nuclear battery that uses an array of thermocouples to convert the heat released by the decay of a suitable radioactive material into electricity by the Seebeck effect. This type of generator has no moving parts. RTGs have been used as power sources in satellites, space probes, and uncrewed remote facilities such as a series of lighthouses built by the Soviet Union inside the Arctic Circle. RTGs are usually the most desirable power source for unmaintained situations that need a few hundred watts (or less) of power for durations too long for fuel cells, batteries, or generators to provide economically, and in places where solar cells are not practical. Safe use of RTGs requires containment of the radioisotopes long after the productive life of the unit. The expense of RTGs tends to limit their use to niche applications in rare or special situations. B ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fusible Alloy
A fusible alloy is a metal alloy capable of being easily fused, i.e. easily meltable, at relatively low temperatures. Fusible alloys are commonly, but not necessarily, eutectic alloys. Sometimes the term "fusible alloy" is used to describe alloys with a melting point below . Fusible alloys in this sense are used for solder. Introduction From a practical view, low-melting alloys can be divided into the following categories: * Mercury-containing alloys *Only alkali metal-containing alloys * Gallium-containing alloys (but neither alkali metal nor mercury) *Only bismuth, lead, tin, cadmium, zinc, indium, and sometimes thallium-containing alloys *Other alloys (rarely used) Some reasonably well-known fusible alloys are Wood's metal, Field's metal, Rose metal, Galinstan, and NaK. Applications Melted fusible alloys can be used as coolants as they are stable under heating and can give much higher thermal conductivity than most other coolants; particularly with alloys made with a hig ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
