Parkes Observatory
From Wikipedia, the free encyclopedia
|
|
|
| Organization | Australia Telescope National Facility |
|---|---|
| Location | Parkes, NSW, Australia |
| Coordinates | |
| Webpage | www.parkes.atnf.csiro.au |
| Telescopes | |
| Parkes Radio Telescope | 64m movable radio dish |
The Parkes Observatory is a radio telescope observatory, 20 kilometres north of the town of Parkes, New South Wales, Australia. It is best known as the dish which sent images of the first moon landing to the rest of the world.
The primary observing instrument is the 64-metre Parkes Radio Telescope, which is the second largest movable dish telescope in the Southern Hemisphere, and one of the first large movable dishes in the world (DSS-43 at Tidbinbilla was extended from 64 m to 70 m in 1987, surpassing Parkes [1].). It was completed in 1961 and 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 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 master-slave 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.
The receiving cabin is located at the focus of the parabolic dish, supported by three struts 27 metres 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.
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 ([2]).
The observatory has remained involved in tracking numerous space missions up to the present day, including those of the Voyager, Giotto, Galileo and Cassini-Huygens probes. It is also a major world centre for research into pulsars, with more than half of those currently known today discovered at the Parkes Observatory.
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.
[edit] Apollo 11 Broadcast
Contrary to popular belief stirred by the film The Dish, the Parkes Observatory was not the first station to broadcast images from the Apollo 11 moon landing. The Goldstone Deep Space Communications Complex in California was initially used to receive the signal, however in light of a very dark, inverted image (due to an incorrect switch position), NASA switched the main feed to the Honeysuckle Creek station outside of Canberra in Australia. Honeysuckle Creek transmitted the images until shortly after the "One small step", when the feed was picked up by Parkes, roughly 3 minutes into the broadcast.
