Thursday, September 2, 2010


The radio telescope at Parkes.

July 21st, 1969. Although I sometimes have trouble remembering what I did yesterday July 21st 1969 is one of those days where I remember exactly where I was and what I was doing. How can I be sure? Well it was the day man landed on the moon.

The Apollo 11 spacecraft piloted by Neil Armstrong, Michael Collins and Buzz Aldrin was launched on July 16th and carried the astronauts to the moon and into the history books. While Collins orbited the moon Armstrong and Aldrin descended to the moon's surface touching down their landing craft, 'The Eagle' on the Sea of Tranquility. They spent 21 hours and 31 minutes on the surface and became the first humans to walk upon the moon.

I was at primary school at the time. I think in year 6. The school stopped and everyone huddled together in rooms to watch this historic event on television. Being seniors, there not being enough TVs, and my grandfather being principal, four or five of us were allowed to go to a student's house near the school and watch it there. The boy whose house we went to was Ian Holt, and I think the other students were Phillip Ewing, Nicky Perriman and Nicholas Baronoff. Like six hundred million people around the globe we did watch the moon walk on TV and we must have been so enthralled that we forgot to return to school after the event and so somehow missed the afternoon lessons.

A poster advertising the movie about the telescope.

Many years later, in 1997 I was appointed to Parkes High School in the middle of the state. Coincidentally, Parkes is the home of the satellite tracking station which relayed the pictures that I, and the rest of the world watched on that day in 1969. The part played by the telescope at Parkes (or at least a version of it) is now well known thanks to a movie made about the event and released on October 19, 2000 called 'The Dish'. I later also watched this movie on a makeshift screen in the paddock beside the historic telescope.

The telescope at Parkes was conceived by E. G. (Taffy) Bowen, then head of the CSIRO's Radiophysics Laboratory. Bowen had been involved with radar during World War II and had made many contacts overseas. He was able to convince both the Carnegie Institute and the California Institute of Technology to fund half the costs for building a telescope in Australia. The then Prime Minister, Robert Menzies, was so impressed with the involvement of these two prestigious bodies that he agreed the government would fund the other half of the project.

An historical photo showing the building of the telescope.

There seemed to be nobody in Australia with the expertise capable of building the telescope and so the CSIRO consulted with Wallis Barnes (of 'dambusters' fame) the chief engineer at Vickers in Great Britain. Wallis came up with some revolutionary ideas for the telescope and the way it was maneuvered. The design for the telescope was completed in 1959 by Freeman Fox (the company that had designed the Sydney Harbour Bridge). A contract for construction of the telescope was then awarded to the Maschinenfabik Augsburg-Nurnberg A.G. Company in Germany and the telescope itself completed in 1961. It has been operating almost continuously since this date.

The telescope as it stands today.

When the moon walk began three stations were receiving the signals back on Earth: NASA's Goldstone station in California, The Honeysuckle Creek station outside of Canberra and the CSIRO's Radio Telescope at Parkes. The signal were being relayed to NASA Mission control in Houston. For the first few minutes NASA switched between Goldstone and Honeysuckle Creek to try obtain the best images. However when they received the images from Parkes they were so superior in quality that they remained with Parkes for the rest of the telecast.

Although the movie does stretch the truth with a few details, one incident is portrayed accurately. In the movie the telescope was plagued by high winds as the walk was due to take place. The winds would be dangerous to the telescope if it was not in the upright position and strapped down. In reality the telescope dish was, at the time of the walk,tipped over on its access waiting for the first signals from the moon as it came above the horizon. Suddenly the structure was hit by 110 kilometre an hour wind gusts which shook the control room and pushed the telescope back on its zenith axis gear. It came very close to Parkes' role in the mission being aborted and the telescope being shutdown until the weather cleared. However the telescope continued to operate outside of its safety parameters but was closely monitored the whole time.

A close-up of the dish showing that it is part covered with metal plates and part mesh.

From Parkes the signal was sent by microwave links to Sydney. In Sydney the signal was split. One signal was sent to the ABC studios to be played on Australian television, the other was sent to Houston where it was distributed to television networks around the world. However the retransmitting from Houston meant there was a delay of 300 milliseconds, thus Australian audiences were the first to see the images of the walk on the moon, albeit by .3 of a second.

The telescope at Parkes is a radio telescope and listens for signals from space. Its dish is 64 metres and is moveable. It often operates in conjunction with the Australia Telescope Compact Array at Narrabri and a single dish at Mopra, near Coonabarabran. The Parkes, Morpa and Narrabri telescopes by operating together use a technique called "interferometry". This allows them to simulate a dish many hundreds of kilometres wide giving scientists the ability to see very fine detail and to form an accurate picture of an area in space in a 12 hour period.and can map a specific area of space. The telescopes are operated by the Australian Telescope National Facility, a division of CSIRO. They are operated for scientific purposes and not for military or defence purposes.

The Parkes telescope operates all year round. It has been involved in tracking space missions, including the Apollo missions in the 1960s, Mariner 2, Mariner 4, Voyager, Giotto, Galileo and Cassini-Huygens probes. It is a world centre for research into pulsars, discovering over half of those known of today. Listed amongst its other achievements are helping to identify the first quasar and discovering magnetic fields in space.

The main characters in the movie discuss problems at the dish.

The movie "The Dish" was directed by Rob Stitch. It was about three fictional staff at the telescope and their American observer during the moon mission. The characters cope with blackouts, high winds and even a love story. At one stage, in the movie, the telescopes main computer is wiped out and the observers lose track of the Apollo 11 spacecraft which they are supposed to be tracking. Scenes involving the telescope where shot on location, including the 'cricket' and the 'hayride' scenes. Other scenes were shot not in Parkes but at Forbes, a town 33 kilometres away. This was done because of the historical buildings still standing at Forbes which better suited the period being portrayed. The movie was written by Santo Cilauro, Tom Gleisner, Jane Kennedy and Rob Stitch. The main actors were Sam Neill, Billy Mitchell, Tom Long and Patrick Warburton. It was nominated for 11 awards, winning 3. The Dish was the highest grossing film in Australia in 200.

A scene from the movie where actors played cricket in the telescope's dish.

Oh...and I did say I remembered July 21st 1969. If you look up articles on the internet you will sometimes come across the date that man walked on the moon as July 20th 1969. This is American time but by Greenwich Mean Time it was July 21st. To be precise it was at 12.56pm Australian Eastern Standard Time. If it had been the 20th I may have missed it, as it was a Sunday and there was no school.

Neil Armstrong was the first man to walk on the moon, followed closely by Buzz Aldrin. How many other men have walked on the moon, and who are they? (Answer at bottom)

An attraction at the telescope and the visitor's centre is the whispering dishes. The shape of the dishes channel voice waves and makes a whisper audible to someone standing at another dish some distance away.

There have been 12 men to walk on the moon. They are:
Neil Armstrong and Buzz Aldrin (Apollo 11, July 21, 1969),
Pete Conrad and Alan Bean (Apollo 12, November 19-20, 1969),
Alan Shepard and Edgar Mitchell (Apollo 14, February 5-6, 1971),
David Scott and james Irwin (Apollo 15, July 31, 1971),
John W Young and Charles Duke (Apollo 16, April 21-23, 1972)
Eugene Cernan and Harrison Schmitt (Apollo 17, December 11-14, 1972)

.............................. of course some people still claim it is all a huge hoax and we have never walked on the moon!