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EISCAT

EISCAT Kiruna Radar (diameter 32m)

EISCAT (European Incoherent Scatter Scientific Association) operates three incoherent scatter radar systems, at 224 MHz, 931 MHz in Northern Scandinavia and one at 500 MHz on Svalbard, used to study the interaction between the Sun and the Earth as revealed by disturbances in the ionosphere and magnetosphere. At the Ramfjordmoen facility (near Tromsø, Norway), it also operates an ionospheric heater facility, similar to HAARP. Additional receiver stations are located in Sodankylä, Finland, and Kiruna, Sweden. The EISCAT Svalbard radar (ESR) is located in Longyearbyen, Norway. The EISCAT Headquarters are also located in Kiruna.

EISCAT is funded and operated by research institutes and research councils of Norway, Sweden, Finland, Japan, China and the United Kingdom (the EISCAT Associates). Institutes in other countries also contribute to operations, including Russia, Ukraine, Germany and South Korea.

The system was also tested for space debris tracking and the radars were proven to be capable of statistical observations of Low-Earth orbit (LEO) debris (altitudes of 500 to 1500 km) down to 2 cm in size. Since these measurements are insufficient to determine complete orbits, the radar has only limited space surveillance value.[1] Because the space debris tracking change is only a dedicated back-end computer system, the primary EISCAT observations are not compromised. As a result of that, the EISCAT radars allow continuous monitoring of the LEO debris in a beam park mode, functioning as a space surveillance system part of the European Space Agency's Space Situational Awareness Programme (SSA).[2]

History

In 1973, the EISCAT proposal — which was originally planned for France, Germany and the three Nordic countries — seemed moribund. Then, Welsh physicist Granville Beynon became involved and by 1975, the agreement was signed, with the UK as a member. The proposal for UK membership had originally been turned down by the appropriate SRC committee. Beynon, however, persuaded the Board to reverse the decision of the committee and as a result of his efforts, hundreds of European scientists have had the opportunity to use the world's most advanced ionospheric radar.[3]

In 2008, Doritos embarked upon an "out-of-this-world" advertising campaign, literally beaming a 30-second advertisement for Doritos brand tortilla chips into a solar system 42 light years away. This project is in collaboration with EISCAT Space Centre in Svalbard. The "You Make It, We'll Play It" contest chose the winning advertisement that was transmitted on June 12, 2008. The ad was beamed towards a distant star, within the Ursa Major constellation which is orbited by planets which may harbor life.[4]

EISCAT facilities
EISCAT Ramfjordmoen facility (near Tromsø) in winter
EISCAT Sodankylä receiver antenna (diameter 32m) after conversion to 224 MHz (crossed dipole replaced Cassegrain subreflector at focal point)

EISCAT operates several facilities north of the Scandinavian arctic circle.[5]

  • At Ramfjordmoen, near Tromsø, Norway the EISCAT facility has: a Ionospheric heater with HF radar capabilities; a tristatic VHF radar at 224 MHz with a 4 x 30m-by-40m parabolic cylinder antenna; and a monostatic UHF radar at 931 MHz with a 32 m parabolic dish antenna.[6] From the start in 1981 the UHF radar was a steerable tristatic system, but due to interference from telecommunications in the 930 MHZ band, the remote receivers were converted to receive the VHF signal during 2012.
  • At Kiruna, EISCAT operates a 32 m parabolic dish antenna receiver which was originally part of the tristatic UHF system but was converted to receive the VHF frequency (224 MHz) during 2012.[6]
  • At Sodankylä, Finland, EISCAT also operates a 32 m VHF-band parabolic dish antenna receiver working at 224 MHz.[6]
  • At Longyearbyen, on the Norwegian Svalbard archipelago, EISCAT operates the EISCAT Svalbard radar (ESR). It consists of a 32 m steerable parabolic dish antenna and a 42 m field aligned antenna, operating at 500 MHz.[5] [6]

The Tromsø VHF transmitter, together with the Kiruna and Sodankylä VHF receivers, form a multistatic radar system.

Additionally, the Kilpisjärvi Atmospheric Imaging Receiver Array (KAIRA), near Kilpisjärvi, Finland can also serve as a VHF receiver in conjunction with the Tromsø transmitter.[7]

EISCAT 3D

EISCAT is planning on building a next generation radar capable of providing 3D monitoring of the atmosphere and ionosphere. The new system is called EISCAT_3D.

In 2008, the European Strategy Forum on Research Infrastructures selected EISCAT_3D for its "Roadmap 2008 for Large-Scale European Research Infrastructures for the next 20–30 years."[8]

EISCAT_3D will be a multistatic radar composed of five phased-array antenna fields. each field will have around 10,000 crossed dipole antenna elements. All five sites will act as receivers, with a singe core site transmitting at 233 MHz (VHF band). The sites will be spread over Finland, Norway and Sweden. Each site will have a central array, surrounded by a set of smaller arrays, providing a high spatial resolution via aperture synthesis.[9]

Preparations for EISCAT_3D

During the summer of 2017, EISCAT will build a 91-element subarray at the site at Ramfjordmoen for hardware testing purposes and the full system is expected to be operational around 2021. The KAIRA system is also a pathfinder for the development of EISCAT_3D.[7]

References
  1. "Europe's Eyes on the Skies" (PDF). ESA. Retrieved 2015-05-06.
  2. "ESA - Space Debris - Scanning & observing". ESA. Retrieved 2015-05-06.
  3. Williams, Phil (April 1996). "Sir Granville Beynon". Archived from the original on 8 October 2011. Retrieved 28 January 2011.
  4. Highfield, Roger (7 March 2008). "UK astronomers to broadcast adverts to aliens". The Daily Telegraph. Retrieved 28 January 2011.
  5. "What is EISCAT". EISCAT. Archived from the original on 2015-10-04. Retrieved 2015-05-23.
  6. "The EISCAT facilities". EISCAT. Retrieved 2017-03-09.
  7. "SGO: KAIRA". SGO. Retrieved 2015-05-24.
  8. "What is Eiscat 3D?"
  9. "EISCAT_3D System configuration". Retrieved 2015-05-27.
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EISCAT

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EISCAT Kiruna Radar (diameter 32m) EISCAT ( European Incoherent Scatter Scientific Association ) operates three incoherent scatter radar systems, at 224 MHz, 931 MHz in Northern Scandinavia and one at 500 MHz on Svalbard , used to study the interaction between the Sun and the Earth as revealed by disturbances in the ionosphere and magnetosphere . At the Ramfjordmoen facility (near Tromsø , Norway ), it also operates an ionospheric heater facility, similar to HAARP . Additional receiver stations are located in Sodankylä , Finland , and Kiruna , Sweden . The EISCAT Svalbard radar ( ESR ) is located in Longyearbyen , Norway. The EISCAT Headquarters are also located in Kiruna . EISCAT is funded and operated by research institutes and research councils of Norway , Sweden , Finland , Japan , China and the United Kingdom (the EISCAT Associates). Institutes in other countries also contribute to operations, including Russia , Ukraine , Germany and South Korea . The system was also tested for space debris tracking and ...more...



Incoherent scatter

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Incoherent scattering is a type of scattering phenomenon in physics . The term is most commonly used when referring to the scattering of an electromagnetic wave (usually light or radio frequency) by random fluctuations in a gas of particles (most often electrons). The most well known practical application is known as incoherent scatter radar theory, a ground-based technique for studying the Earth's ionosphere first proposed by Professor Bill Gordon in 1958. A radar beam scattering off electrons in the ionospheric plasma creates an incoherent scatter return. The distribution function of the ionospheric electrons is modified by the much slower and more massive positive ions — electron density fluctuations relate to ion temperature, mass distribution, and motion. The incoherent scatter signal allows measurement of electron density , ion temperature and electron temperatures, ion composition and plasma velocity. See also EISCAT Millstone Hill Observatory Arecibo Observatory Jicamarca Radio Observatory Sondrestro ...more...



KAIRA

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The Kilpisjärvi Atmospheric Imaging Receiver Array (KAIRA) is an astronomical observatory operated by the Sodankylä Geophysical Observatory on behalf of Oulu University . It is located at Kilpisjärvi , Enontekiö near the border with Norway . It comprises two LOFAR -derived radio telescope systems and is capable of observing at HF and VHF radio frequencies. It is used for atmospheric, near-Earth space and astronomical research. KAIRA uses LOFAR phased-array antennas and digital signal-processing hardware. The phased array configuration has no moving parts and with digital control, allows KAIRA to quickly scan the sky, giving KAIRA a large field of view. KAIRA can produce a continuous all-sky image of the radio transparency of ionosphere , using cosmic radio noise for "illumination" ( riometry ). KAIRA can also obtain electron density profiles in the atmosphere. In addition to near-space imaging, the use of KAIRA has been demonstrated for long-baseline interferometry observations of pulsars . It operates as e ...more...



Ionospheric heater

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An ionospheric heater , or an ionospheric HF pump facility, is a powerful radio wave transmitter with an array of antennas which is used for research of plasma turbulence, the ionosphere and upper atmosphere. These transmitters operate in the high frequency (HF) range (3-30 MHz) at which radio waves are reflected from the ionosphere back to the ground. With such facilities a range of plasma turbulence phenomena can be excited in a semi-controlled fashion from the ground, during conditions when the ionosphere is naturally quiet and not perturbed by for example aurora. This stimulus-response type of research complements passive observations of naturally excited phenomena to learn about the ionosphere and upper atmosphere. The plasma turbulence phenomena that are studied include different types on nonlinear wave interactions, in which different waves in the plasma couple and interact with the transmitted radio wave, formation and self organization of filamentary plasma structures, as well as electron accelerati ...more...



Granville Beynon

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Sir William John Granville Beynon , CBE , FRS (24 May 1914 in Dunvant – 11 March 1996 in Aberystwyth ) was a Welsh physicist . He co-operated with Sir Edward Victor Appleton , who had detected the terrestrial Ionosphere . Life history William John Granville Beynon was born in Dunvant , near Swansea , Wales on 24 May 1914, the youngest of four children. His father, a miner, held the responsible jobs of checkweightman and chief of the local mines rescue service. Beynon was educated at Gowerton Grammar School, before matriculating to the University of Swansea , where he studied physics. In 1938 he gained a position at National Physical Laboratory at Slough , near London, working closely with Sir Edward Appleton . Together they performed basic studies of radio wave propagation by reflection from these layers. This cooperation persisted over a few decades, during which Beynon as representative of Sir Edward held senior offices in national and international committees, and took active part in the preparation and ...more...



Tor Hagfors

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Tor Hagfors (18 December 1930 – 17 January 2007) was a Norwegian scientist , radio astronomer , radar expert and a pioneer in the studies of the interactions between electromagnetic waves and plasma . In the early 1960s he was one of a handful of pioneering theorists that independently developed a theory that explained the scattering of radio waves by the free electrons in a plasma and applied the result to the ionosphere . He became founding director of the new EISCAT facilities that were then under construction in 1975, by which time he already been director at most of the other incoherent scatter radar facilities in the world. The asteroid 1985 VD1 is named 7279 Hagfors after him. Early life Tor Hagfors was born in Oslo in 1930. He studied at the Norwegian Institute of Technology (NTH) and received his doctorate degree in 1959 from the University of Oslo . Scientific work Hagfors worked at the Norwegian Defence Research Establishment from 1955 to 1963, interrupted by a sabbatical at Stanford University fro ...more...



ESR

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Look up ESR in Wiktionary, the free dictionary. ESR may refer to: Organizations Ethnikó Simvúlio Radhiotileórasis , the Greek National Council for Radio and Television Institute of Environmental Science and Research , a New Zealand scientific institute Earlham School of Religion , at Earlham College in Richmond, Indiana, US E.S.R., Inc. , a former American toy manufacturer ESR Rīga , a Soviet Latvian football club, active from 1966 to 1991 ESR Technology , a UK company European Society of Radiology Science EISCAT Svalbard radar , UHF-band radar at Longyearbyen, Norway Electron spin resonance , a technique used in chemical spectroscopy to identify unpaired electrons and free radicals Electron spin resonance dating , a dating technique used in fields such as archaeology and geology Erythrocyte sedimentation rate , the rate at which red blood cells sediment Estrogen receptor , a group of proteins Technology Electro-slag remelting , an alloy remelting and refining process Electronic Staff Record , a human resourc ...more...



List of Arctic research programs

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This is a list of Arctic research programs : Arctic Centre, University of Lapland Arctic Institute of North America Arctic Research Consortium of the United States (ARCUS) Arctic Research Foundation Arctic Research Office Arctic Submarine Laboratory Arctic Technology Centre Arctic and Antarctic Research Institute Byrd Polar Research Center British Antarctic Survey Canadian High Arctic Ionospheric Network Centre for Polar Observation & Modelling Circumarctic Environmental Observatories Network Cooperative Institute for Arctic Research EISCAT Flashline Mars Arctic Research Station Institute of Arctic and Alpine Research Institute of Arctic Biology Institute of Arctic Studies (Dartmouth) Institute of the North International Arctic Buoy Program International Arctic Research Center International Arctic Science Committee International Laboratory for the Multidisciplinary Study of Representations of the North North Greenland Ice Core Project North Pacific Research Board (NPRB) Northern Research Network National ...more...



Joe Armstrong (programming)

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Joseph "Joe" Leslie Armstrong (27 December 1950 in Bournemouth, England ) is a computer scientist working in the area of fault-tolerant distributed systems. He is best known as the author of the Erlang programming language . Biography Armstrong was born in Bournemouth in 1950. At 17, Armstrong began programming Fortran on his school district's mainframe. This experience helped him during his physics studies at University College London , where he debugged the programs of his fellow students in exchange for beer. While working for the Ericsson Computer Science Lab, he helped developing Erlang in 1986. He received a Ph.D. in computer science from the Royal Institute of Technology (KTH) in Stockholm, Sweden in 2003. He has been a professor at KTH since 2014. Personal life Work Peter Seibel wrote: Originally a physicist, he switched to computer science when he ran out of money in the middle of his physics PhD and landed a job as a researcher working for Donald Michie —one of the founders of the field of artifici ...more...



Multistatic radar

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A multistatic radar system contains multiple spatially diverse monostatic radar or bistatic radar components with a shared area of coverage. An important distinction of systems based on these individual radar geometries is the added requirement for some level of data fusion to take place between component parts. The spatial diversity afforded by multistatic systems allows for different aspects of a target to be viewed simultaneously. The potential for information gain can give rise to a number of advantages over conventional systems. Multistatic radar is often referred to as 'multisite' or 'netted' radar, and is comparable with the idea of macrodiversity in communications. A further subset of multistatic radar with roots in communications is that of MIMO radar. Characteristics Since multistatic radar may contain both monostatic and bistatic components, the advantages and disadvantages of each radar arrangement will also apply to multistatic systems. A system with N {\displaystyle N} transmitters and M {\displ ...more...



High Frequency Active Auroral Research Program

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The High Frequency Active Auroral Research Program ( HAARP ) was initiated as an ionospheric research program jointly funded by the US Air Force , the U.S. Navy , the University of Alaska Fairbanks , and the Defense Advanced Research Projects Agency (DARPA). It was designed and built by BAE Advanced Technologies (BAEAT). Its original purpose was to analyze the ionosphere and investigate the potential for developing ionospheric enhancement technology for radio communications and surveillance. As a university-owned facility HAARP is a high-power, high-frequency transmitter used for study of the ionosphere. The most prominent instrument at HAARP is the Ionospheric Research Instrument (IRI), a high-power radio frequency transmitter facility operating in the high frequency (HF) band. The IRI is used to temporarily excite a limited area of the ionosphere . Other instruments, such as a VHF and a UHF radar , a fluxgate magnetometer , a digisonde (an ionospheric sounding device), and an induction magnetometer, are u ...more...



Polar mesospheric summer echoes

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Polar mesospheric summer echoes (PMSE) is the phenomenon of anomalous radar echoes found between 80-90 km in altitude from May through early August in the Arctic, and from November through to February in the Antarctic. These strong radar echoes are associated with the extremely cold temperatures that occur above continental Antarctica during the summer. Rocket and radar measurements indicate that a partial reflection from a multitude of ion layers and constructive interference causes at least some of the PMSE. Generally PMSE exhibits dramatic variations in height and intensity as well as large variations in Doppler shift . PMSE exhibit strong signal power enhancements of scattering cross section at VHF radar frequencies in the range 50 MHz to 250 MHz, at times even to over 1 GHz, that occur in summer at high latitudes. The peak PMSE height is slightly below the summer mesopause temperature minimum at 88 km, and above the noctilucent cloud (NLC) and/or polar mesospheric cloud (PMC) layer at 83–84 km. The usual ...more...



Longyearbyen

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Longyearbyen ( Norwegian pronunciation:  (lit. The Longyear Town) is the largest settlement and the administrative centre of Svalbard , Norway . As of December 2015, the town had a population of 2,144. Longyearbyen is located in the Longyear Valley and on the shore of Adventfjorden , a bay of Isfjorden located on the west coast of Spitsbergen . Since 2002, Longyearbyen Community Council has had many of the same responsibilities of a municipality , including utilities, education, cultural facilities, fire brigade, roads and ports. The town is the seat of the Governor of Svalbard . It is the world's northernmost settlement of any kind with greater than 1,000 permanent residents. Known as Longyear City until 1926, the town was established by and named after John Munro Longyear , whose Arctic Coal Company started coal mining operations in 1906. Operations were taken over by Store Norske Spitsbergen Kulkompani (SNSK) in 1916, which still conducts mining. The town was almost completely destroyed by the German Krieg ...more...



Swedish Institute of Space Physics

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The Swedish Institute of Space Physics ( Swedish : Institutet för rymdfysik , IRF) is a Swedish government agency . The institute's primary task is to carry out basic research, education and associated observatory activities in space physics, space technology and atmospheric physics. Foundation The IRF was founded in 1957 and the first Kiruna-designed satellite experiment was launched in 1968. The institute has about one hundred employees and has its head office in Kiruna . Other offices are situated in Umeå , Uppsala and Lund . IRF, originally the Kiruna Geophysical Observatory , began as a department within the Royal Swedish Academy of Sciences. It has been a public research institute since 1973, under the auspices of the Swedish Ministry of Education and Culture. Satellite experiments Swedish Institute of Space Physics andThe Kiruna Space Campus IRF participates in several international satellite projects. At present, data from satellite instruments are being analysed to help us better comprehend the plasm ...more...



Michael Lockwood (physicist)

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Michael "Mike" Lockwood FRS (born 1954) is a Professor of Space Environment Physics at the University of Reading . Life and works Schooled at The Skinners' School , Tunbridge Wells , he earned his BSc (1975) and then PhD (1978) degrees at the University of Exeter . Much of his career has been with Rutherford Appleton Laboratory but he has also worked at University of Southampton , NASA 's Marshall Space Flight Center and University of Auckland . His research interests comprise, among others, variations in the magnetic fields of the Sun, interplanetary space, and the Earth and in general solar influence on global and regional climate. He has served as the Chair of the Council of EISCAT and as a Council member for the British Natural Environment Research Council . His lectures, at the Saas-Fee Advanced Course The Sun, Solar Analogs and the Climate, together with contributions of such experts as Joanna Haigh and Mark Giampapa, were published as a book by Springer in 2006. He played football during his postdoc s ...more...



Kiruna

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Kiruna ( Northern Sami : Giron , Finnish : Kiiruna ) is the northernmost town in Sweden , situated in the province of Lapland . It had 18,148 inhabitants in 2010 and is the seat of Kiruna Municipality (population: 23,099 in 2008 ) in Norrbotten County . Esrange Space Center was established in Kiruna in the 1960s. Also in Kiruna are the Institute of Space Physics and the Department of Space Science belonging to Luleå University of Technology . History Origins Archeological findings have shown that the region around Kiruna has been inhabited for at least 6,000 years. Centuries before Kiruna was founded in 1900, the presence of iron ore at Kiirunavaara and Luossavaara had been known by the local Sami population. In 1696, Samuel Mört, a bookkeeper of the Kengis works, wrote on the presence of iron in the two hills. The Swedish senior enforcement officer and cartographer and mapper Anders Hackzell mapped the Kiruna area in 1736 and gave the mountains of the area their Swedish language names Fredriks berg (origin ...more...



Bo Thidé

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Bo Y. Thidé (born in Gothenburg , Sweden) is a Swedish physicist who studies radio waves and other electromagnetic radiation in space, particularly their interaction with matter and fields. He received his B.Sc. in 1972, his M.Sc. in 1973, and defended his Ph.D. thesis on semiclassical quantum theory at Uppsala University in 1979. His Ph.D. was obtained under the supervision of professor Per Olof Fröman at the Department of Theoretical Physics, Uppsala University. He has worked at the Swedish Institute of Space Physics in Uppsala since 1980, where he has been a professor since 2000. In 1981, Bo Thidé discovered electromagnetic emissions stimulated by powerful radio waves in the ionosphere during experiments in August 1981 at the EISCAT facility in Tromsø , Norway. For the first time it was shown that the plasma turbulence excited by powerful radio waves in the ionosphere radiates secondary electromagnetic radiation that can be detected and analysed on the ground. These stimulated electromagnetic emissions (S ...more...



Sodankylä

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Sodankylä ( Inari Sami : Suáđigil , Northern Sami : Soađegilli , Skolt Sami : Suäʹđjel ) is a municipality of Finland . It is located in the region of Lapland , and lies at the northern end of Finnish national road 5 . The municipality has a population of 8,556 (31 August 2017) and covers an area of 11,691.73 square kilometres (4,514.20 sq mi) of which 718.65 km (277.47 sq mi) is water. The population density is 0.73 inhabitants per square kilometre (1.9/sq mi). Neighbouring municipalities are Inari , Kemijärvi , Kittilä , Pelkosenniemi , Rovaniemi , and Savukoski . The municipality has two official languages: Finnish and Northern Sami . Since 1986, Sodankylä has been home to the Midnight Sun Film Festival ( Sodankylän elokuvajuhlat ). The Jaeger Brigade of the Finnish Army is also located in Sodankylä. Although the name "Sodankylä" and (also "Soađegilli") directly translate to "Village of War", the etymology of the name is from a surname rather than the word "war". One of EISCAT 's scientific radar receiv ...more...



PCI Express

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Intel P3608 NVMe flash SSD, PCI-E add-in card PCI Express ( Peripheral Component Interconnect Express ), officially abbreviated as PCIe or PCI-e , is a high-speed serial computer expansion bus standard, designed to replace the older PCI , PCI-X , and AGP bus standards. PCIe has numerous improvements over the older standards, including higher maximum system bus throughput, lower I/O pin count and smaller physical footprint, better performance scaling for bus devices, a more detailed error detection and reporting mechanism (Advanced Error Reporting, AER ), and native hot-plug functionality. More recent revisions of the PCIe standard provide hardware support for I/O virtualization . The PCI Express electrical interface is also used in a variety of other standards, most notably the laptop expansion card interface ExpressCard and computer storage interfaces SATA Express and M.2 . Format specifications are maintained and developed by the PCI-SIG (PCI Special Interest Group ), a group of more than 900 companies tha ...more...



List of radars

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This is a list of radars . A radar is an electronic system used to detect, range (determine the distance of), and map various types of targets. Argentina INVAP 2D INKAN monopulse radar, already deployed at Bariloche and Quilmes and building 15 more INVAP 3D long range radar, operative since 2011 Australia Surface-based Jindalee - Over the horizon radar, air and sea search radar. Naval CEAFAR CEA Technologies a 4th generation multifunction digital active phased array radar. Brazil Surface-based EDT-FILA SABER M60 Airborne SCP-01 Scipio Under development SENTIR M20 SABER M200 Europe Surface-based ARTHUR - ARTillery HUnting Radar, artillery locating radar Active Phased Array Radar - sea-based radar for Dutch and German navies DARS D eployable A ir operations centre, R ecognized air picture production centre, S ensor Fusion Post. A new state of the art mobile deployable NATO Command & Control radarsystem controlling and safeguarding the operational airspace anywhere in the world. L3/2 radar - short range air ...more...



Walter Dieminger

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Walter Dieminger , (July 7, 1907 – September 29, 2000) was a German space scientist and director of Germany's Max Planck Institute for Aeronomy from 1955 to 1975. Dieminger's research was focused on the ionosphere . Life and work Dieminger studied physics between 1926 and 1935 at the University of Technology Munich . After receiving his Ph.D. for work on electromagnetic waves and the ionosphere with Jonathan Zenneck , he worked at the Deutsche Versuchsanstalt für Luftfahrt (German Experimental Institute for Aviation). With his focus on research of the ionosphere and electromagnetic waves at his new institute, called the Zentralstelle für Funkberatung (Central Counseling Office for Radio Communication). Applying a code invented by his cooperator Karl Rawer he was able to make predictions on shortwave communication for the military and the police. The institute at Leobersdorf continued to monitor the ionosphere until the end of World War II . A group of British physicists supervised the dissolution of the insti ...more...



Space debris

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A computer-generated image representing space debris as could be seen from high Earth orbit . The two main debris fields are the ring of objects in geosynchronous Earth orbit (GEO) and the cloud of objects in low Earth orbit (LEO). Space debris , Space junk , Space waste , Space trash , or Space litter or "Space Garbage" is the collection of defunct human-made objects in earth orbit, such as old satellites , spent rocket stages , and fragments from disintegration, erosion , and collisions – including those caused by the space debris itself. As of December 2016, five satellite collisions have resulted in generating space waste. As of 5 July 2016, the United States Strategic Command tracked a total of 17,852 artificial objects in orbit above the Earth, including 1,419 operational satellites. However, these are just objects large enough to be tracked. As of July 2013, more than 170 million debris smaller than 1 cm (0.4 in), about 670,000 debris 1–10 cm, and around 29,000 larger debris were estimated to be in o ...more...



Doritos

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Doritos ( ) is an American brand of flavored tortilla chips produced since 1964 by Frito-Lay , a wholly owned subsidiary of PepsiCo . History The original product was made at the Casa de Fritos (now Rancho Del Zocalo) at Disneyland in Anaheim, California , during the early 1960s. Using surplus tortillas and taking the original idea from the traditional Mexican snack known as totopo , the company-owned restaurant cut them up and fried them and added basic seasoning, resembling the Mexican chilaquiles , but in this case being dry. Arch West was the vice president of marketing of Frito-Lay at the time, and noticed their popularity. He made a deal in 1964 with Alex Foods, the provider of many items for Casa de Fritos at Disneyland, and produced the chips for a short time regionally, before it was overwhelmed by the volume, and Frito-Lay moved the production in-house to its Tulsa plant. "Doritos" were released nationwide in 1966, the first tortilla chip to be launched nationally in the United States. The name der ...more...



Space Situational Awareness Programme

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The Space Situational Awareness ( SSA ) Programme is the European Space Agency 's initiative designed to support Europe's independent space access and utilization through the timely and accurate information delivery regarding the space environment, and particularly hazards to both in orbit and ground infrastructure. The SSA programme is split into three main segments: Space Weather (SWE) segment: monitoring the Sun , the solar wind , and in Earth’s magnetosphere , ionosphere and thermosphere , that can affect spaceborne and ground-based infrastructure or endanger human life or health Near-Earth Objects (NEO) segment: detecting natural objects, such as asteroids and comets , which can potentially impact Earth Space Surveillance and Tracking (SST) segment: Tracking active and inactive satellites and space debris (collectively these items are referred to as Resident Space Objects (RSOs)). The SSA programme is being implemented as an optional ESA programme with financial participation by 14 Member States. The pr ...more...



Ionosphere

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The ionosphere ( ) is the ionized part of Earth's upper atmosphere , from about 60 km (37 mi) to 1,000 km (620 mi) altitude, a region that includes the thermosphere and parts of the mesosphere and exosphere . The ionosphere is ionized by solar radiation. It plays an important role in atmospheric electricity and forms the inner edge of the magnetosphere . It has practical importance because, among other functions, it influences radio propagation to distant places on the Earth . Relationship of the atmosphere and ionosphere History As early as 1839, the German mathematician and physicist Carl Friedrich Gauss postulated that an electrically conducting region of the atmosphere could account for observed variations of Earth's magnetic field. Sixty years later, Guglielmo Marconi received the first trans-Atlantic radio signal on December 12, 1901, in St. John's, Newfoundland (now in Canada ) using a 152.4 m (500 ft) kite-supported antenna for reception. The transmitting station in Poldhu , Cornwall, used a spark-gap ...more...



Beam park

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Beam park is a radar mode used for space surveillance , particularly tracking space debris . In beam-park mode, a radar beam is kept in a fixed direction with respect to the Earth, while objects passing through the beam are tracked. In 24 hours, as a result of the Earth’s rotation, the radar effectively scans a narrow strip through 360° of the celestial sphere . The scattered waves are detected by a receiver and the measurements obtained during the observations can be used to determine object radar cross-section , time of peak occurrence, polarization ratio, doppler shift and object rotation. The obtained information for each object is then processed and matched against data from previously catalogued objects. The beam-park mode can be used to detect both previously known and uncatalogued objects at any altitude, provided that the reflected power captured by the receiver can be distinguished from the noise. This limits the use of radar-based beam park observations to objects in Low-Earth Orbit (LEO). Optica ...more...



LOFAR

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The Low-Frequency Array or LOFAR , is a large radio telescope located mainly in the Netherlands, completed in 2012 by ASTRON , the Netherlands Institute for Radio Astronomy and its international partners, and operated by ASTRON's radio observatory, of the Netherlands Organisation for Scientific Research. LOFAR consists of a vast array of omnidirectional antennas using a new concept in which the signals from the separate antennas are not combined in real time as they are in most array antennas . The electronic signals from the antennas are digitized, transported to a central digital processor, and combined in software to emulate a conventional antenna. The project is based on an interferometric array of radio telescopes using about 20,000 small antennas concentrated in at least 48 stations. Forty of these stations are distributed across the Netherlands and were funded by ASTRON. The five stations in Germany , and one each in Great Britain , France and Sweden , were funded by these countries. Further stations m ...more...



Jicamarca Radio Observatory

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The Jicamarca Radio Observatory (JRO) is the equatorial anchor of the Western Hemisphere chain of Incoherent Scatter Radar (ISR) observatories extending from Lima , Peru to Søndre Strømfjord, Greenland . JRO is the premier scientific facility in the world for studying the equatorial ionosphere . The Observatory is about half an hour drive inland (east) from Lima and 10 km from the Central Highway ( 11°57′05″S 76°52′27.5″W  /  11.95139°S 76.874306°W , 520 meters ASL). The magnetic dip angle is about 1°, and varies slightly with altitude and year. The radar can accurately determine the direction of the Earth's magnetic field (B) and can be pointed perpendicular to B at altitudes throughout the ionosphere . The study of the equatorial ionosphere is rapidly becoming a mature field due, in large part, to the contributions made by JRO in radio science . JRO’s main antenna is the largest of all the incoherent scatter radars in the world. The main antenna consists of a 300m x 300m square array composed of 18,432 cr ...more...



List of observatory codes

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This is a list of observatory codes , or IAU codes , with their corresponding astronomical observatories . The Minor Planet Center (MPC) – a service of the International Astronomical Union – assigns for each registered observatory a 3-digit code. The code serves as a unique identifier for observations taken of hundreds of thousands of minor planets and thousands of comets orbiting in the Solar System . More than 150 millions such astrometric records exist. This list is based on MPC's periodically published and revised "List Of Observatory Codes". Over time, the number of astronomical observatories worldwide has been growing constantly. As of May 2016, MPC's official list contains a total of 1972 observatories. The registry is limited to observatories which perform minor planet observations. While this includes most optical telescopes of note and a great many amateur facilities, it does not include the U.S. National Solar Observatory or many notable radio observatories (such as the Llano de Chajnantor Observ ...more...





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