Editing Australia Telescope Compact Array

{{Short description|Radio telescope in New South Wales, Australia}}
{{Use dmy dates|date=April 2022}}
{{Infobox Telescope}}

The '''Australia Telescope Compact Array''' ('''ATCA''') is a [[radio telescope]] operated by [[Commonwealth Scientific and Industrial Research Organisation|CSIRO]] at the [[Paul Wild Observatory]], twenty five kilometres (16&nbsp;mi) west of the town of [[Narrabri, New South Wales|Narrabri]] in New South Wales, Australia.<ref name=Sault>{{cite web |url=https://www.narrabri.atnf.csiro.au/public/ |title=Australia Telescope Compact Array: Information for the public |author=Sault, Bob |author2=Mirtschin, Peter |date=14 December 2018 |publisher=CSIRO |access-date=2 February 2020}}</ref> Its opening ceremony took place on September 2, 1988.<ref>{{Cite web|date=2013-09-02|title=Monday memories: Opening ATCA|url=https://blog.csiro.au/opening-atca/|access-date=2022-01-04|website=CSIROscope|language=en-AU}}</ref>

==Overview==
The telescope is an array of six identical {{convert|22|m|adj=on}} diameter dishes, which commonly operate in [[aperture synthesis]] mode to produce [[radio]] images. Five of the dishes can be moved along a three-kilometre (2&nbsp;mi) railway track oriented east-west. The sixth antenna is situated three kilometres west of the end of the main track. Each dish weighs about {{convert|270|t}}.

The Compact Array is a part of the [[Australia Telescope National Facility]] network of radio telescopes. The array is frequently operated together with other CSIRO telescopes, the {{convert|64|m|adj=on}} dish at the [[Parkes Observatory]] and a single {{convert|22|m|adj=on}} dish at [[Mopra Observatory|Mopra]] (near [[Coonabarabran, New South Wales|Coonabarabran]]), to form a [[Very Long Baseline Interferometry|very long baseline interferometry]] array.<ref name=Sault/>

The Array welcomes visitors from the general public. The facility includes a Visitor's Centre where the operations of the array can be observed in comfort and shade, and it has a range of informational displays and audiovisual presentations, while the surrounding grounds have displays and activities for visitors.  Open Days are run regularly, and to mark special events such as the anniversary of the first Moon landing, or major anniversaries of the telescope itself.<ref>{{cite web|title=Narrabri Visitors Centre: Visiting the Observatory |url=http://www.atnf.csiro.au/outreach/visiting/narrabri/index.html |publisher=[[Commonwealth Scientific and Industrial Research Organisation|CSIRO]]|access-date=16 June 2014}}</ref>

The children's/teen's television adventure series ''[[Sky Trackers]]'' was filmed in this facility in 1993,<ref name=":9">{{Cite journal|last=Wallace|first=Alex|date=August 1993|title=CSIRO - sky tracking across the universe and our television screens|url=https://csiropedia.csiro.au/wp-content/uploads/2018/09/coresearch_1993.pdf|journal=CoResearch - CSIRO's Staff Newsletter|issue=354|pages=8}}</ref> with the radio telescopes being prominently featured.

<gallery>
CSIRO ScienceImage 227 Five Antennas at Narrabri.jpg|Five of the antennas (2000)
ATCA Radio Telescope Narrabri 2005 12 21.jpg|One antenna vertically aligned (2005)
CSIRO ScienceImage 104 Closeup of Australia Telescope Compact Array Construction.jpg|The array under construction (1988<ref>{{cite web|url=http://www.atnf.csiro.au/outreach/about/history/building-atca/index.html|title=Building the ATCA|work=csiro.au|access-date=20 February 2016}}</ref>)
ATCA night observers 2013 09 01.JPG|Star gazing beside the array, as part of its 25th anniversary celebrations on 1 September 2013.
</gallery>

=== Space tracking ===
Whilst remaining a telescope predominantly dedicated to radio-astronomy,<ref name=":9" /> in 2007, the Compact Array was outfitted with receivers enabling it to receive radio waves 7&nbsp;mm long, allowing it to be used from time to time to help [[NASA]] track spacecraft.<ref name=":7">{{Cite web |date=February 2013 |title=The Australia Telescope Compact Array – Fast Facts |url=https://www.narrabri.atnf.csiro.au/public/open_day/2013/ATCA_FastFacts_2013.pdf |url-status=live |website=CSIRO|archive-url=https://web.archive.org/web/20140815071109/http://www.narrabri.atnf.csiro.au/public/open_day/2013/ATCA_FastFacts_2013.pdf |archive-date=2014-08-15 }}</ref>

==Key results==
Highlights of the scientific work done by the ATCA include:<ref>{{cite web |title=Science from the ATCA |url=https://www.atnf.csiro.au/outreach/about/achievements/ATCA/index.html |website=www.atnf.csiro.au |publisher=CSIRO Australia Telescope National Facility |access-date=28 May 2021 |language=en |date=2021-04-20}}</ref>
:'''1991''' the first image of a radio supernova remnant as it formed ([[SN 1987A|SNR 1987A]] in the Large Magellanic Cloud)
:'''1992''' observe the longest galactic radio jets to date (galaxy 0319-453).
:'''1995''' create the first 3-D models of Jupiter’s radiation belts, showing properties of its magnetic field closer to the planet than spacecraft could measure.
:'''1996''' create the most detailed maps of hydrogen in the [[Magellanic Clouds]], by a factor of 20.
:'''1998''' first evidence that [[gamma-ray burst]]s are linked to [[supernova]]e.
:'''2000''' observations suggest that radio beams from the giant radio galaxy B0114-476 may have turned off, then restarted.
:'''2001''' observations suggest that Abell 3667, a cluster of about 500 galaxies, was produced by two smaller clusters merging. This is the first observational evidence for this process.
:'''2001''' (with [[Anglo-Australian Telescope|Parkes telescope]]) the first three-dimensional structure of a face-on galaxy (the Large Magellanic Cloud).
:'''2002''' (with [[Chandra X-ray Observatory|Chandra X-ray space telescope]]) for the first time capture the entire life-cycle of jets from a microquasar, XTE J1550-564, seeing jets erupt at relativistic speeds, slow down and fade away.
:'''2003''' show that gamma ray bursts release similar total energy, and so probably have a common origin.
:'''2004''' first observations of a neutron star emit a jet at relativistic speed.  This challenged the idea that only black holes can create the conditions needed to accelerate jets to such extreme speeds.

== See also ==
*[[John Paul Wild]], founder of the observatory
*[[List of radio telescopes]]
*[[Radio Galaxy Zoo]]

==References==
{{Reflist}}

==External links==
{{Commons category|Australia Telescope Compact Array}}
* [http://www.narrabri.atnf.csiro.au/ Australia Telescope Compact Array Home Page] contains links for the general public and for professional astronomers
*[https://csiropedia.csiro.au/australia-telescope-compact-array/ Australia Telescope Compact Array] at CSIROpedia
* [http://www.narrabri.atnf.csiro.au/cgi-bin/Public/atca_live.cgi ATCA Live! website] shows current observations
* [http://www.narrabri.atnf.csiro.au/ATCACam ATCA sky camera] shows the sky above the ATCA

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[[Category:Radio telescopes]]
[[Category:Interferometric telescopes]]
[[Category:Astronomical observatories in New South Wales]]
[[Category:Cosmic microwave background experiments]]
[[Category:North West Slopes]]