The CSIRO's 64-metre Parkes Radio Telescope, also known as 'The Dish', was commissioned in 1961, so we are fortunate to be able to celebrate its 60th anniversary on October 30.
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At the time, it was the most advanced radio telescope in the world, incorporating many new innovative design features that have since become standard in all large dish antennas.
Through its early discoveries it quickly became the leading instrument of its kind in the world.
Today, 60 years after it was commissioned, it is still arguably the finest single-dish radio telescope in the world.
It is still doing world-class science and making discoveries that are shaping our understanding of the Universe.
In the lead up to the anniversary this Sunday, CSIRO's operations scientist, John Sarkissian OAM, walks us through how The Dish came about, and all that the telescope has achieved over the past 60 years.
In Part 1 we look at what preceded the idea for a giant radio telescope, and the birth of radiophysics in Australia.
In early 1939, Richard Casey, the then Minister of Supply and Development in the Australian Commonwealth Government, learned of a highly secret scientific development from Britain known as Radio Direction Finding, or radar, as it became known.
With little information to go on, but shrewdly sensing that this might be a significant development, he immediately set in motion the process of founding a secret laboratory to investigate this development.
It was given the innocuous title of the Radiophysics Laboratory to hide its top-secret military purpose.
For security reasons, the Radiophysics Laboratory was built as an extension of the National Standards Laboratory, part of Australia's Council for Scientific and Industrial Research (CSIR), the forerunner of the CSIRO.
From 1939 to 1942, with the war in Europe raging, Casey resigned from Parliament and travelled to Washington DC to open the first Australian diplomatic mission in a foreign country.
He developed a close relationship with the President, Mr Roosevelt, and with the principal leaders of his Administration and Congress.
He thus founded a firm political relationship between the USA and Australia, which proved invaluable in the dark days that followed as the Japanese invasion of Australia loomed.
In 1942, Casey accepted an invitation from the British Prime Minister, Winston Churchill, to become the Australian representative on his War Cabinet.
The purpose of the Radiophysics Laboratory was to develop radar for use in the Pacific theatre.
On the Sydney cliff tops at Dover Heights overlooking the Pacific Ocean, the Royal Australian Air Force established a coastal defence radar station as part of the wartime defences of Sydney, and the Radiophysics Laboratory used the site as a field station for its experimental radar work.
During the war, radar operators reported strong radio emissions from the Sun, however, the pressing wartime needs took precedence and the investigations into the origin of these solar emissions had to wait until after the war.
At war's end, other similar labs around the world were disbanded, but in Australia, the decision was made to keep the lab intact and to redirect its research into peaceful applications.
This included using radar to improve air navigation (important for a large country like Australia).
Another project initiated at this time was the study of the origin of the radio emissions from the Sun that had so intrigued the radar operators during the war.
In 1946, Edward 'Taffy' Bowen was appointed the Chief of the Radiophysics Laboratory.
Taffy had been one of the brilliant engineers, dubbed the 'Boffins', who developed radar as part of the secret, pre-war British development.
Bowen had been given the task of developing a radar unit small enough to fit in an aircraft, and by 1937, his group had built a complete airborne radar system.
This invention eventually contributed to the British victory in the Battle of Britain.
Bowen later led the British team who travelled to the United States to divulge the radar secrets to the US, and it was there that he met Richard Casey and the two formed a firm friendship.
Bowen was a dynamic leader who brought great energy to his new role, as well as a network of influential contacts he had built up during his wartime experience in the United States.
The radio astronomy group within Radiophysics, was led by J.L. (Joe) Pawsey.
He pioneered the use of a technique known as the "sea interferometer" to investigate the solar radio emissions.
Located at the top of a sheer cliff at Dover Heights, just south of the entrance to Sydney Harbour, Pawsey and his colleagues used surplus Yagi antennas (similar to television aerials commonly seen on rooftops) to make their pioneering observations of the Sun.
As the Sun rose above the Pacific Ocean, radio emission from the Sun reached the cliff-top aerial along two paths - one direct and the other reflected by the sea's surface.
From the interference pattern so generated it was possible to locate the source of the emission to an accuracy of just a few minutes of arc on the sky, and this was accurate enough to identify sunspots as the source of much of the solar emission.
Pawsey's group included many brilliant engineers, who went on to become world-leaders in the nascent field of radio astronomy.
Some of the brilliant engineers included: Bernie Mills, Chris Christiansen, Paul Wild, Ruby Payne Scott (the first female radio astronomer), and John Bolton.
John Bolton was a 24-year-old Radar Officer serving on the Royal Navy's aircraft carrier, HMS Unicorn, in the Pacific.
He was discharged in Sydney at the end of the war, and the following day, John Bolton met Taffy Bowen for an interview at the Radiophysics Laboratory.
Bowen immediately took a liking to him and offered Bolton a position of technical research assistant and was set to work with Pawsey on the solar studies.
Bolton's attention however, soon switched to identifying other, non-solar sources of radio emission.
Within the next two years, Bolton, working with colleagues Gordon Stanley and Bruce Slee, conducted observations with the sea interferometer which resulted in the identification of four new radio sources - Cygnus A, Taurus A, Centaurus A and Virgo A.
Initially, the radio positions were very poor, but using larger, multi-element Yagi antennas, they were able to increase the sensitivity and resolution of their instruments.
By the early 1950's, over 100 sources of radio emission were discovered at Dover Heights, and these ranged from supernovae remnants, and other sources in our own Milky Way Galaxy as well as from very distant galaxies.
These observations established the Radiophysics Laboratory as a world-leading centre of radio astronomy, and opened up the study of the Universe at radio wavelengths, from the solar system to the cosmos.
Observations with this, and with a later enlarged 24.4-metre (80-ft) version, led to the detailed observations of the Milky Way Galaxy's centre, which today is recognised as containing a supermassive black hole.
By 1954, the technology at Dover Heights was becoming outdated and the work that could be done with the simple equipment was exhausted.
By then, the radiophysics teams were universally recognized as world leaders in radio astronomy.
This led Taffy Bowen to initiate the next step in the development of radio astronomy in Australia.
