Anglo-Australian Telescope

Anglo-Australian Telescope
Organisation Australian Astronomical Observatory
Location(s) Siding Spring Observatory, Australia
Coordinates 31°16′31″S 149°04′02″E / 31.2754°S 149.0672°E / -31.2754; 149.0672Coordinates: 31°16′31″S 149°04′02″E / 31.2754°S 149.0672°E / -31.2754; 149.0672
Wavelength optical, IR
Built 1974
First light April 27, 1974 (1974-04-27)
Telescope style prime/Cassegrain/coudé
Diameter 3.9 m (12 ft 10 in)
Collecting area 12 m2 (130 sq ft)
Focal length 12.7 m (42 ft)
Mounting equatorial
Enclosure spherical
Website www.aao.gov.au/about-us/anglo-australian-telescope

The Anglo-Australian Telescope (AAT) is a 3.9-metre equatorially mounted telescope operated by the Australian Astronomical Observatory and situated at the Siding Spring Observatory, Australia at an altitude of a little over 1,100 m. In 2009, the telescope was ranked as the fifth highest-impact of the world's optical telescopes. In 2001–2003, it was considered the most scientifically productive 4 metre-class optical telescope in the world based on scientific publications using data from the telescope.[1][2]

The telescope was commissioned in 1974 with a view to allowing high quality observations of the sky from the southern hemisphere. At the time, most major telescopes were located in the northern hemisphere, leaving the southern skies poorly observed.[3] It was the largest telescope in the Southern hemisphere from 1974-1976, then a close second to the Victor M. Blanco Telescope from 1976 until 1998, when the first ESO VLT was opened. The AAT was credited with stimulating a resurgence in British optical astronomy.[3] It was constructed by Australia and the United Kingdom but has been entirely funded by Australia since 2010.[4] Observing time is available to astronomers worldwide.

The AAT was one of the last large telescopes built with an equatorial mount. More recent large telescopes have instead adopted the more compact and mechanically stable altazimuth mount. The AAT was, however, one of the very first telescopes to be fully computer-controlled, and set new standards for pointing and tracking accuracy.

History

Richard van der Riet Woolley pushed for a large optical telescope for the southern hemisphere in 1959.[3] A Joint Policy Committee started work on construction planning in August 1967. It took until September 1969 for plans to be finalised.[5] The agreement initially committed the specification to a telescope design based on the Kitt Peak telescope until its deficiencies were known. Both the horseshoe mount and the gearing system needed improvements.[6] Although the revised gear system was considerably more expensive it was significantly more accurate, lending itself well to unforeseen applications.[6]

The mirror was made by Owens-Illinois in Toledo, Ohio. It was then transported to Newcastle, England where Sir Howard Grubb, Parsons and Co took two years to grind and polish the mirror's surface.[6] Mitsubishi Electric built the mount which was constructed by August 1973. First light occurred on 27 April 1974. The telescope was officially opened by Prince Charles on 16 October 1974.[6]

Structure

The telescope is housed within a seven-story, circular, concrete building. It was designed to withstand the high winds prevailing at that location. The slit is narrow. The dome is required to move with the telescope to avoid obstruction.[6] The dome structure is 118 feet (36 m) high.

Instruments

3.9-metre equatorially mounted telescope

The AAT is equipped with a number of instruments, including :

HERMES will be commissioned in 2013. It is a new spectrograph to be used with the 2dF fibre positioner.[7] HERMES will be used for the ‘Galactic Archaeology‘ (GA) Survey, which aims to reconstruct the history of our galaxy's formation from precise multi-element (~25) abundances of 1  million stars derived from HERMES spectra.

Comparisons

The AAT was built just a little smaller and built later than the Mayall 4m, but the AAT views the southern sky.

Largest optical astronomical telescopes in the late 1970s
# Name /
Observatory		 Image Aperture M1
Area 		Altitude First
Light 		Special advocate
1. BTA-6
(Special Astrophysical Obs)		 238 inch
605 cm		 26 m2 2,070 m (6,790 ft) 1975 Mstislav Keldysh
2. Hale Telescope
(Palomar Observatory)		 200 inch
508 cm		 20 m2 1,713 m (5,620 ft) 1949 George Ellery Hale
3. Mayall Telescope
(Kitt Peak National Obs.)		 158 inch
401 cm 		10 m2 2,120 m (6,960 ft) 1973 Nicholas Mayall
4. Víctor M. Blanco Telescope
(CTIO Observatory)		 158 inch
401 cm 		10 m2 2,200 m (7,200 ft) 1976 Nicholas Mayall
5. Anglo-Australian Telescope
(Siding Spring Observatory)		 153 inch
389 cm 		12 m2 1,742 m (5,715 ft) 1974 Prince Charles
6. ESO 3.6 m Telescope
(La Silla Observatory)		 140 inch
357 cm		 8.8 m2 2,400 m (7,900 ft) 1976 Adriaan Blaauw
7. Shane Telescope
(Lick Observatory)		 120 inch
305 cm		 ~7 m2 1,283 m (4,209 ft) 1959 Nicholas Mayall

See also

References

  1. ↑ Fred Watson (6 January 2009). "Across the universe". Sydney Morning Herald. Retrieved 8 November 2011.
  2. ↑ Tammy Plonter (11 September 2008). "Australian Telescope Leads the World In Astronomy Research". Universe Today.
  3. 1 2 3 Home, Roderick Weir (1990). Australian Science in the Making. Cambridge University Press. p. 360. ISBN 0521396409. Retrieved 6 December 2015.
  4. ↑ Nick Lomb (June 15, 2010). "Australia's largest optical telescope to become part of the Australian Astronomical Observatory on 1 July 2010 and to celebrate its 36th birthday". Sydney Observatory.
  5. ↑ Gregory, Jane (2005). Fred Hoyle's Universe. Oxford University Press. p. 225. ISBN 0191578460. Retrieved 15 April 2013.
  6. 1 2 3 4 5 Haynes, Raymond (1996). Explorers of the Southern Sky: A History of Australian Astronomy. Cambridge University Press. pp. 382–394. ISBN 0521365759. Retrieved 15 April 2013.
  7. ↑ "HERMES project AAT". Department of Industry, Innovation, Climate Change, Science, Research and Tertiary Education. Archived from the original on 9 April 2013. Retrieved 15 April 2013.

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