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SOUTH AFRICA's Meerkat RADIO TELESCOPE SOUTHSOUTH AFRICA’SAFRICA’S MMeerKATeerKAT More than 20 MeerKAT antennas have been installed on the SKA SA Losberg site outside Carnarvon in the Northern Cape. RADIORADIO TELESCOPE MARCH 2014 TECHNICAL FACT SHEET TheThe SouthSouth AfricanAfrican MeerKATMeerKAT radioradio telescope,telescope, currentlycurrently beingbeing LOCALWHO IS PARTICIPATION MANUFACTURING IN THE builtbuilt somesome 90 90 kmkm from north-west Carnarvon of the in thesmall Northern Northern Cape, Cape is atown CONSTRUCTIONTHE MeerKAT ANTENNAS? OF MeerKAT precursorof Carnarvon, to the is Squarea precursor Kilometre to the Array Square (SKA) Kilometre telescope Array and will StratosatStratosat Datacom (Pty)(Pty) Ltd, thethe contractorprimary industry for the partner design, manufacturingon the be(SKA) integrated telescope into and the will mid-frequency be integrated component into the mid-frequency of SKA Phase andmanufacturing acceptance of thethe MeerKAT Antennaantennas, Positioner, leads a technology leads a technology 1.component The SKA Project of SKA isPhase an international 1. The SKA Projectenterprise is an to international build the consortiumconsortium including including international international partners partners General General Dynamics Dynamics Satcom largestenterprise and tomost build sensitive the largest radio and telescope most sensitive in the world, radio and telescope will be (GDSatcom,Satcom (GDSatcom, USA) and USA) Vertex and Antennentechnik Vertex Antennentechnik (Germany). (Germany). locatedin the world, in Africa and and will Australia. be located in Africa and Australia. At least 75% of the components making up the MeerKAT dish will be Atmanufactured least 75% of inthe South contract Africa value by will several be spent sub-contractors. in South Africa Keyresulting local in most TIMELINE FOR MeerKAT CONSTRUCTION ofsuppliers the MeerKAT include antenna Effi cient components Engineering being (pedestals manufactured and in yokes); South Africa. Titanus March 2014: First antenna installed Slew Rings (azimuth bearings) and Tricom Structures (back-up March 2014: First antenna installed Mid 2014: First antenna qualifi ed and critical design review Keystructure), local suppliers all based include in Gauteng. Efficient In someEngineering cases foreign(pedestals companies and yokes); Titanus Slew Rings (azimuth bearing), Tricom Structures and Namaqua June 2016: completed16 antenna array ready will manufacture components for the fi rst antenna – such as the fi rst End 2014: Four MeerKAT receptors will be fully assembled, Engineeringset of refl ector (back-up panels, structure), fi rst receiver Westarcor indexer Engineering and fi rst sub-refl and General ector Profiling (receiver indexer); and Stratosat (reflectors). End 2017: integrated64 antenna and verifi array ed ready – but the rest will be made locally. Suppliers from abroad include End 2015: Array to ofdo 16 science antennas commissioned and ready to the National Research Council of Canada, through the Herzberg, Due to schedule pressure some of the components (such as the reflector do science Programs in Astronomy and Astrophysics (low-noise amplifi ers and panels, sub-reflector and receiver indexer) for the first two antennas End 2016: All 64 antenna positioners will be in place. fi rst sub-refl ector); Oxford Cryogenics in the UK (cryogenic cold- were manufactured internationally. Since then, this function has been Mid 2017: Full array ready to do science. heads) and Vertex Antennentechnik (control systems). successfully transferred to local suppliers. highhigh with with a adeviation deviation from from thethe ideal ideal shape shape being being no no moremore than than 0.6 0.6 mm mm RMS RMS (root(root mean mean square). square). The The mainmain reflector reflector surface surface is is mademade up up of of 40 40 aluminium aluminium panelspanels mounted mounted on on a asteel steel supportsupport framework. framework. Z Z This This framework framework is is mountedmounted on on top top of of a ayoke, yoke, whichwhich is is in in turn turn mounted mounted onon top top of of a apedestal. pedestal. The The combinedcombined height height of of the the pedestalpedestal and and yoke yoke is is just just overover 8 8m. m. The The height height of of the the total total structure structure is is 19.519.5 m, m, and and it it weighs weighs 42 42 tons. tons. Z Z The The pedestal pedestal houses houses the the antenna’s antenna’s pointing pointing control control system. system. Z Z Mounted Mounted at at the the top top of of the the pedestal, pedestal, beneath beneath the the yoke, yoke, are are an an TheThe MeerKAT MeerKAT will will become become part part of of SKA SKA phase phase 1. 1. azimuthazimuth drive drive and and a ageared geared azimuth azimuth bearing, bearing, which which allow allow the the mainmain and and sub-reflectors, sub-reflectors, together together with with the the receiver receiver indexer, indexer, to to MMeereerKAT’SKAT’S MAK MAKE-UPE-UP bebe rotated rotated horizontally. horizontally. The The yoke yoke houses houses the the azimuth azimuth wrap, wrap, which which (see(see annotated annotated diagram diagram on on back back page): page): guidesguides all all the the cables cables when when the the antenna antenna is is rotated, rotated, and and prevents prevents Z Z The The MeerKAT MeerKAT telescope telescope will will be be an an array array of of 64 64 interlinked interlinked themthem from from becoming becoming entangled entangled or or damaged. damaged. The The structure structure receptorsreceptors (a (a receptor receptor is is the the complete complete antenna antenna structure, structure, with with allowsallows an an observation observation elevation elevation range range from from 15 15 to to 88 88 degrees, degrees, thethe main main reflector, reflector, sub-reflector sub-reflector and and all all receivers, receivers, digitisers digitisers and and andand an an azimuth azimuth range range from from -185 -185 degrees degrees to to +275 +275 degrees, degrees, where where otherother electronics electronics installed). installed). northnorth is is at at zero zero degrees. degrees. Z Z The The configuration configuration (placement) (placement) of of the the receptors receptors is is determined determined by by Z Z The The steerable steerable antenna antenna positioner positioner can can point point the the main main reflector reflector thethe science science objectives objectives of of the the telescope. telescope. veryvery accurately, accurately, to to within within 5 5arcseconds arcseconds (1.4 (1.4 thousandths thousandths of of a a Z Z 48 48 of of the the degree)degree) under under low-wind low-wind and and night-time night-time observing observing conditions, conditions, receptorsreceptors are are andand to to within within 25 25 arcseconds arcseconds (7 (7 thousandths thousandths of of a adegree) degree) during during concentratedconcentrated normalnormal operational operational conditions. conditions. inin the the core core areaarea which which is is ABOUABOUTT M MeereerKATKAT – – HOW HOW I TIT WOR WORKKS:S: approximatelyapproximately Antenna foundations in the coreZ ofZ Electromagnetic Electromagnetic the MeerKAT waves waves from from cosmic cosmic radio radio sources sources bounce bounce off off the the 1 1km km in in diameter. diameter. array, as seen in this image from Februarymainmain reflector, reflector, 2014. then then off off the the sub-reflector, sub-reflector, and and are are then then focused focused in in Z Z The The longest longest thethe feed feed horn, horn, which which is is part part of of the the receiver. receiver. distancedistance between between Z Z Each Each receptor receptor can can accommodate accommodate up up to to four four receivers receivers and and anyany two two receptors receptors digitisersdigitisers mounted mounted on on the the receiver receiver indexer. indexer. The The indexer indexer is is a a (the(the so-called so-called rotatingrotating support support structure structure that that allows allows the the appropriate appropriate receiver receiver AntennaAntenna foundations foundations in inin the thethe core corecore of ofof the thethe MeerKAT MeerKATMeerKAT maximummaximum toto be be automatically automatically moved moved into into the the antenna antenna focus focus position, position, array,array, as as seen seenseen when inwhen this flying flyingimage over over from the the February Karoo Karoo site, site,2014. baseline)baseline) dependingdepending on on the the desired desired observation observation frequency. frequency. FebruaryFebruary 2014. 2014. isis 8 8km. km. Z Z The The main main function function of of the the receiver receiver is is to to capture capture the the Z Z Each Each MeerKAT MeerKAT receptor receptor consists consists of of three three main main components: components: electromagneticelectromagnetic radiation radiation and and convert convert it it to to an an voltage voltage signal signal that that 1.1. The The antenna antenna positioner, positioner, which which is is a asteerable steerable dish dish on on a a isis then then amplified amplified by by cryogenic cryogenic receivers receivers that that add add very very little little noise noise pedestal;pedestal; toto the the signal. signal. The The first first two two receivers receivers will will be be the the L-Band L-Band and and UHF- UHF- 2.2. A A set set of of radio radio receivers; receivers; BandBand Receivers. Receivers. 3.3. A Aset set of of associated associated digitisers. digitisers. Z Z Four Four digitisers digitisers will will be be mounted mounted on
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