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Line 1: {{Short description\|Radar systems used to study the interaction between the Sun and the Earth}} ~~[[Image:EISCAT Svalbard Radar.jpg\|right\|thumb\|The two antennas of the EISCAT Svalbard Radar]]~~ {{Primary sources\|date=July 2022}} ~~[[Image:EISCAT dish Kiruna.JPG\|right\|thumb\|EISCAT Kiruna Radar (diameter 32m)]]~~ [[Image:EISCAT Sodankylä radar.JPG\|right\|thumb\|EISCAT Sodankylä receiver antenna (diameter 32m) after conversion to 224 MHz (crossed dipole replaced Cassegrain subreflector at focal point)]][[Image:EISCAT dish Kiruna.JPG\|right\|thumb\|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]],. The facilities are used to study the interaction between the [[Sun]] and the [[Earth]] as revealed by disturbances in the [[ionosphere]] and [[magnetosphere]].<ref>{{Cite Atweb ~~the~~\|title=Mission ~~Ramfjordmoen~~statement ~~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~~Scientific ~~radar'''~~Association ~~('''ESR''') is located in [[Longyearbyen]], Norway~~\|url=https://eiscat.se/about/organisation/mission-statement/ ~~The~~\|access-date=2022-12-08 ~~EISCAT Headquarters are also located in [[Kiruna]]~~\|website=eiscat.se}}</ref> The EISCAT Scientific Association exists to provide scientists with access to incoherent scatter radar facilities of the highest technical standard. 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]]. == EISCAT 3D ==▼ The system was also tested for [[space debris]] [[space surveillance\|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 [[orbit]]s, the radar has only limited space surveillance value.<ref name=bulletin>{{cite web\|url=http://www.esa.int/esapub/bulletin/bulletin133/bul133f_klinkrad.pdf\|title=Europe's Eyes on the Skies\|publisher=[[ESA]]\|access-date=2015-05-06}}</ref> 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).<ref>{{cite web\| url = http://www.esa.int/Our_Activities/Operations/Space_Debris/Scanning_observing \|title=ESA - Space Debris - Scanning & observing\|publisher=ESA\|access-date=2015-05-06}}</ref> The construction of EISCAT's new generation of incoherent radars: EISCAT 3D, has started in November 2022. The first stage of the new system will consist of three radar sites, functioning together, just as the old mainland system. Later, transmitter up grade and more sites will be added to the system. <ref>{{Cite web \|title=EISCAT_3D – EISCAT Scientific Association \|url=https://eiscat.se/eiscat3d-information/ \|access-date=2022-12-08 \|website=eiscat.se}}</ref> ==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.<ref name=mist /> Instead of parabolic dishes, as the old system, EISCAT 3D is a [[multistatic radar]] composed of three [[Phased-array radar\|phased-array]] antenna fields. Many small antennas working together as one. Each field will have between 5 000 - 10 000 crossed [[dipole antenna]] mounted on top of a ground plane 70 meters in diameter. 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.<ref name=telegraph /> The core site of EISCAT 3D is located just outside [[Skibotn]], Norway. The facility will have 109 hexagonal antenna units as its main antenna, and 10 antenna units spread out around the main site. On top of the antenna units the dipole antennas are mounted. The Skibotn facility will have 10 000 of these small antennas. The Skibotn facility will act both as a transceiver and receiver of the EISCAT 3D system. ~~== EISCAT facilities==~~ ~~[[Image:Ramfjordmoen forskningsstasjon winter 1.jpg\|right\|thumb\|EISCAT Ramfjordmoen facility (near Tromsø) in winter]]~~ ▲[[Image:EISCAT Sodankylä radar.JPG\|right\|thumb\|EISCAT Sodankylä receiver antenna (diameter 32m) after conversion to 224 MHz (crossed dipole replaced Cassegrain subreflector at focal point)]] Two receiver sites are located in [[Karesuvanto\|Karesuvando]], Finland and Kaiseniemi, Sweden. The facilities will consist of 54 and 55 antenna units with approximately 5 000 dipole antennas.<ref>{{Cite web \|title=EISCAT_3D design and science – EISCAT Scientific Association \|url=https://eiscat.se/eiscat3d-information/eiscat_3d-design-and-science/ \|access-date=2022-12-08 \|website=eiscat.se}}</ref> EISCAT operates several facilities north of the [[Scandinavia]]n [[arctic circle]].<ref name=eiscat-new>{{cite web\| url=https://www.eiscat.se/about/whatiseiscat_new\| title=What is EISCAT\| publisher=EISCAT\| access-date=2015-05-23\| deadurl=yes\| archiveurl=https://web.archive.org/web/20151004043210/https://www.eiscat.se/about/whatiseiscat_new\| archivedate=2015-10-04\| df=}}</ref> * 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]].<ref name=eiscat-facilities>{{cite web\| url=https://www.eiscat.se/scientist/document/technical-specifications/\| title=The EISCAT facilities\| publisher=EISCAT\| access-date=2017-03-09}}</ref> 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.<ref name=eiscat-facilities /> * At [[Sodankylä]], Finland, EISCAT also operates a 32 m VHF-band parabolic dish antenna receiver working at 224 MHz.<ref name=eiscat-facilities /> * 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.<ref name=eiscat-new /><ref name=eiscat-facilities /> [[Space debris]] tracking, tracking of [[Meteorite\|meteorites]], research on [[GPS]] and radio traffic, [[space weather]], [[aurora]] research, [[climate]] research and near-Earth space are some of the areas where EISCAT 3D will be able to offer much more flexible and meticulous research data. ~~The Tromsø VHF transmitter, together with the Kiruna and Sodankylä VHF receivers, form a [[multistatic radar]] system.~~ The use of EISCAT 3D is solely civil.<ref>{{Cite book \|title=EISCAT BlueBook \|year=2021 \|pages=8–13}}</ref>[[Image:EISCAT Svalbard Radar.jpg\|right\|thumb\|The two antennas of the EISCAT Svalbard Radar]]The new system should be up and running 2023/2024. This also means that the old mainland system will be dismantled. Additionally, the [[KAIRA\|Kilpisjärvi Atmospheric Imaging Receiver Array]] (KAIRA), near [[Kilpisjärvi]], Finland can also serve as a VHF receiver in conjunction with the Tromsø transmitter.<ref name=kira>{{cite web\| url=http://www.sgo.fi/KAIRA/\| title=SGO: KAIRA\| publisher=SGO\| access-date=2015-05-24}}</ref> == The mainland system == ▲==EISCAT 3D== The mainland system consisted of three parabolic dish research radar antennas, designed as a tristatic radar, that is, three facilities that work together. The radar antennas are located in [[Tromsø]], Norway; [[Sodankylä]], Finland and [[Kiruna]], Sweden, north of the [[Scandinavia\|Scandinavian]] [[Arctic Circle]]. The core in the tri-static system, is located at Ramfjordmoen, outside Tromsø, Norway with a 32 meter mechanically fully steerable parabolic dish used for transmission and reception in the [[UHF]]-band. Operating in the 930 MHz band with a transmitter peak power 2.0 MW, 12.5% duty cycle and 1 μs – 10 ms pulse length with frequency and phase modulation capability. ~~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'''.~~ And the [[VHF]] radar that operates in the 224 MHz band with transmitter peak power 3 MW, 12.5% duty cycle and 1 μs – 2 ms pulse length with frequency and phase modulation capability. The antenna, used for transmission and reception, is a parabolic cylinder antenna consisting of 4 quarters, constituting a total aperture of 120 m x 40 m. This antenna is mechanically steerable in the meridional plane (-30° to 60° zenith angle), and electronically steerable in the longitudinal direction (±12° off-boresight).<ref>{{Cite web \|title=Technical specifications – EISCAT Scientific Association \|url=https://eiscat.se/scientist/document/technical-specifications/ \|access-date=2022-12-08 \|website=eiscat.se}}</ref>[[Image:Ramfjordmoen forskningsstasjon winter 1.jpg\|right\|thumb\|EISCAT Ramfjordmoen facility (near Tromsø) in winter]]The receiving antennas in Sodankylä, Finland and Kiruna, Sweden, is fully steerable 32 meter parabolic dish antennas. The receivers include multiple channels the UHF radar and the VHF radars. The data are pre-processed in signal processors, displayed and analysed in real-time and can be recorded to mass storage media.<ref>{{Cite web \|title=Sites – EISCAT Scientific Association \|url=https://eiscat.se/about/sites/ \|access-date=2022-12-08 \|website=eiscat.se}}</ref> 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."<ref>{{Cite web \|url=http://www.eiscat3d.se/idea \|title="What is Eiscat 3D?" \|access-date=2012-02-14 \|archive-url=https://web.archive.org/web/20150527232716/https://www.eiscat3d.se/idea \|archive-date=2015-05-27 \|dead-url=yes }}</ref> ▲== EISCAT ~~facilities~~Svalbard Radar == EISCAT_3D will be a [[multistatic radar]] composed of five [[phased-array radar\|phased-array]] antenna fields. each field will have around 10,000 crossed [[dipole antenna]] elements. All five sites will act as receivers, with a single 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]].<ref>{{cite web\| url=https://www.eiscat3d.se/status2015/configuration\| title=EISCAT_3D System configuration\| access-date=2015-05-27}}</ref> The location in [[Longyearbyen]], [[Svalbard]], high above the arctic circle and near the north pole, offers unique capabilities in auroral research. Svalbard’s unique climate with polar night from November until February, make the season for observing the northern lights long. The EISCAT Svalbard Radar (ESR) also operates the UHF-band, at 500 MHz with a transmitter peak power of 1000 kW, 25 % duty cycle and 1 μs – 2 ms pulse length with frequency and phase modulation capability.<ref>{{Cite web \|title=Technical specifications – EISCAT Scientific Association \|url=https://eiscat.se/scientist/document/technical-specifications/ \|access-date=2022-12-08 \|website=eiscat.se}}</ref> There are two antennas, a 32 meter mechanically fully steerable parabolic dish antenna, and a 42 meter fixed parabolic antenna aligned along the direction of the local geomagnetic field.<ref>{{Cite web \|title=EISCAT Svalbard Radar – EISCAT Scientific Association \|url=https://eiscat.se/about/sites/eiscat-svalbard-radar/ \|access-date=2022-12-08 \|website=eiscat.se}}</ref> ~~=== 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.<ref name=kira /> The whole radar system is controlled by computers, and the sites in Tromsø, Kiruna, Sodankylä, and Longyearbyen are interconnected via the Internet. ==References==▼ {{Reflist\|refs=▼ <ref name=telegraph>{{cite news \|url=https://www.telegraph.co.uk/news/science/science-news/3335306/UK-astronomers-to-broadcast-adverts-to-aliens.html \|title=UK astronomers to broadcast adverts to aliens \|last=Highfield \|first=Roger \|date=7 March 2008 \|newspaper=[[The Daily Telegraph]] \|accessdate=28 January 2011}}</ref> == Tromsø Ionospheric Modification facility == <ref name=mist>{{cite web \|url=http://www.mist.ac.uk/beynon.html \|title=Sir Granville Beynon \|last=Williams \|first=Phil \|date=April 1996 \|publisher= \|accessdate=28 January 2011 \|deadurl=yes \|archiveurl=https://web.archive.org/web/20111008183411/http://www.mist.ac.uk/beynon.html \|archivedate=8 October 2011 \|df= }}</ref> An [[Ionospheric heater\|ionospheric heating]] facility, Heating, is also located in Ramfjordmoen outside Tromsø, Norway. It consists of 12 transmitters of 100 kW CW power, which can be modulated, and three antenna arrays covering the frequency range 3.85 MHz to 8 MHz.<ref>{{Cite web \|title=EISCAT Tromsø site – EISCAT Scientific Association \|url=https://eiscat.se/about/sites/eiscat-tromso-site/ \|access-date=2022-12-08 \|website=eiscat.se}}</ref> }} ▲==History== EISCAT was founded in December 1975, as an association of research councils in six member countries. But the plans to establish a research facility focusing on incoherent scatter technology in the Northern Lights zone, started as early as 1969. Many meetings with interested researchers were held in the early 70s, but it was not until [[Granville Beynon\|Professor Sir Granville Beynon]] organized a meeting in 1973, where a board and a chairman were appointed, that the work really began. In 1974, the Council presented a report on how the organisation, operations and implementation of EISCAT's UHF system could take place, and at the end of 1975 the first six member states agreed to start the work towards the construction of EISCAT. The member countries are now Sweden, Norway, Finland, Japan, China and the United Kingdom. The members have changed somewhat: Germany is no longer a full member, France was a member from the start of the organization in 1975 until 2005, while Japan and China were added later (1996 and 2007 respectively). EISCAT is governed by [https://eiscat.se/about/organisation/eiscat-council/ The EISCAT Council], which consists of representatives from research institutions in the various member countries. Two committees, the Administrative and Financial Committee (AFC) and the Advisory Scientific Committee (SAC), assist the Council in its work.<ref>{{Cite web \|title=EISCAT Council – EISCAT Scientific Association \|url=https://eiscat.se/about/organisation/eiscat-council/ \|access-date=2022-12-08 \|website=eiscat.se}}</ref> ▲==References== ▲{{Reflist~~\|refs=~~}} ==External links== {{~~commons~~Commons category\|European Incoherent Scatter Scientific Association}} https://eiscat.se/about/ [http://www.eiscat.se/groups/Documentation/Publications/ Publication List] ~~[http~~https://~~www.~~eiscat.se/~~about About EISCAT]~~eiscat3d-information/ [https://~~eiscat3d~~eiscat.se ~~EISCAT_3D website]~~/eiscat3d-information/eiscat_3d-faq/ *[http://www.unis.no/ University Courses on Svalbard (UNIS)] {{Magnetospherics}} {{coord\|69\|35\|10.67\|N\|19\|13\|28.62\|E\|type:landmark\|display=title}}▼ {{Authority control}} ▲{{~~coord~~Coord\|69\|35\|10.67\|N\|19\|13\|28.62\|E\|type:landmark\|display=title}} [[Category:Arctic research]] [[Category:Ionosphere]] [[Category:Pan-European scientific societies]] [[Category:Longyearbyen]] [[Category:Kiruna]]