Parkes Observatory

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Parkes Observatory
Parkes.arp.750pix.jpg
The Parkes Observatory in New South Wales, Australia
Organization Australia Telescope National Facility
Location Parkes, New South Wales, Australia
Coordinates
Established 31 October 1961
Website
www.parkes.atnf.csiro.au
Telescopes
Parkes Radio Telescope 64m movable radio dish
The Parkes radio telescope can tilt 60° from vertical and would take 15 minutes to perform a 360° rotation.

The Parkes Observatory (also known informally as "The Dish") is a radio telescope observatory, located 20 kilometres north of the town of Parkes, New South Wales, Australia. It was one of several radio antennas used to receive live, televised images of the Apollo 11 moon landing on 20 July 1969. Its scientific contributions over the decades led the ABC to describe it as "the most successful scientific instrument ever built in Australia"[1] after 40 years of operation.

The Parkes Observatory is run by the CSIRO as part of the Australia Telescope National Facility (ATNF) network of radio telescopes. It is frequently operated together with other CSIRO radio telescopes, principally the array of six 22-metre (72 ft) dishes at the Australia Telescope Compact Array near Narrabri, and a single 22-metre (72 ft) dish at Mopra (near Coonabarabran), to form a very long baseline interferometry array.

Radio telescope[edit]

The Parkes 64m Radio Telescope "The Dish" at full extension to the ground.

The Parkes Radio Telescope, completed in 1961, was the brainchild of E.G. (Taffy) Bowen, chief of the CSIRO's Radiophysics Laboratory. During the Second World War, he had worked on radar development in the US and had made some powerful friends in the scientific community. Calling on this old boy network, he persuaded two philanthropic organisations, the Carnegie Corporation and the Rockefeller Foundation to fund half the cost of the telescope. It was this recognition and key financial support from the US that persuaded then Prime Minister Robert Menzies to agree to fund the rest of the project.[2]

Hardware[edit]

The primary observing instrument is the 64-metre (210 ft) movable dish telescope, second largest in the Southern Hemisphere, and one of the first large movable dishes in the world (DSS-43 'Deep Space Station'-43 at Tidbinbilla was extended from 64-metre (210 ft) to 70-metre (230 ft) in 1987, surpassing Parkes).[3] After its completion it has operated almost continuously to the present day. The dish surface was physically upgraded by adding smooth metal plates to the central part to provide focusing capability for centimetre and millimetre length microwaves. The outer part of the dish remains a fine metal mesh, creating its distinctive two-tone appearance.

The 18-metre (59 ft) dish antenna was transferred from the Fleurs Observatory (Mills Cross) in 1963. Mounted on rails and powered by a tractor engine to allow the distance between it and the main dish to be easily varied, it was used as an interferometer with the main dish, and as a transmit uplink antenna in the Apollo program. It has been abandoned since the early 1980s.

The telescope has an altazimuth mount. It is guided by a small mock-telescope placed within the structure at the same rotational axes as the dish, but with an equatorial mount. The two are dynamically locked when tracking an astronomical object by a laser guiding system. This primary-secondary approach was designed by Barnes Wallis.

The success of the Parkes telescope led NASA to copy the basic design in their Deep Space Network, with matching 64 m dishes built at Goldstone, Madrid and Tidbinbilla.

Receivers[edit]

The receiving cabin is located at the focus of the parabolic dish, supported by three struts 27-metre (89 ft) above the dish. The cabin contains multiple radio and microwave detectors, which can be switched into the focus beam for different science observations.

The observatory is a part of the Australia Telescope National Facility network of radio telescopes. The 64m dish is frequently operated together with the Australia Telescope Compact Array at Narrabri and a single dish at Mopra, to form a very long baseline interferometry array.

Historical non-astronomy research[edit]

During the Apollo missions to the moon, the Parkes Observatory was used to relay communication and telemetry signals to NASA, providing coverage for when the moon was on the Australian side of the Earth.[4]

The telescope also played a role in relaying data from the NASA Galileo mission to Jupiter that required radio-telescope support due to the use of its backup telemetry subsystem as the principal means to relay science data.

The big dish

The observatory has remained involved in tracking numerous space missions up to the present day, including

The observatory and telescope were featured in the 2000 film The Dish, a fictionalised account of the observatory's involvement with the Apollo 11 moon landing.

The CSIRO has made several documentaries on this observatory, with some of these documentaries being posted to YouTube.[1]

Apollo 11 broadcast[edit]

ABC news report on the role of the Parkes telescope and the Honeysuckle Creek Tracking Station, a week before the moon landing.

When Buzz Aldrin switched on the TV camera on the Lunar Module, three tracking antennas received the signals simultaneously. They were the 64 metre Goldstone antenna in California, the 26 metre antenna at Honeysuckle Creek near Canberra in Australia, and the 64 metre dish at Parkes.

In the first few minutes of the broadcast, NASA alternated between the signals being received from its two stations at Goldstone and Honeysuckle Creek, searching for the best quality picture.

A little under nine minutes into the broadcast, the TV was switched to the Parkes signal. The quality of the TV pictures from Parkes was so superior that NASA stayed with Parkes as the source of the TV for the remainder of the 2.5 hour broadcast. For a comprehensive explanation of the TV reception of the Apollo 11 broadcast, see "The Television Broadcasts" from the report "On Eagles Wings".

On Monday, 31 October 2011, Google replaced its logo with a Google Doodle in honor of Parkes Observatory's 50th Anniversary.[5] It was only visible on Google in Australia.

Celebrations on 19 July 2009 to mark the 40th anniversary of the moon landing, and Parkes' role in it. "The Dish" behind is at full extension to the ground.

Mars rovers[edit]

In 2012 the Observatory received special signals from the Mars rover Opportunity (MER-B), to simulate the Curiosity rover UHF radio.[6] This helped prepare for the then upcoming Curiosity (MSL) landing in early August—it successfully touched down on 6 August 2012.[6]

Astronomy research timeline[edit]

1960s

  • Built 1961 and was fully operational by 1963.
  • Support for the NASA Apollo Missions in late 1960s.

1970s

  • Receiver upgrades and detailed observations begin.

1980s

  • Upgrade to 64m from previously smaller aperture.

1990s

  • Between 1997 and 2002 it conducted the HIPASS neutral hydrogen survey, the largest blind survey for galaxies in the neutral hydrogen line to date.

2000s

See also[edit]

References[edit]

External links[edit]