A TELESCOPE FOR A GOLDEN AGE

After a stellar 50 years as one of the country's major scientific assets, the AAT continues to play a major role in keeping Australian astronomy on the world stage.

- FRED WATSON

BACK IN SEPTEMBER 1969 in a laboratory in north-eastern England, a young, newly minted physics graduate was engaged in a job that no more than a dozen people worldwide would be doing. It was a humble task – fabricating a circular polyethylene air-bag 3.9m in diameter and no more than a couple of centimetres thick. What made the job unique was the purpose of this unwieldy plastic pouch. Once pressurised, it would cushion a 16-tonne disc of an exotic glass-ceramic material known as Cer-Vit while it was ground and polished during many months to form the precisely dished mirror of a giant telescope.

That starstruck youngster was me and this was my first encounter with the Anglo-Australian Telescope – the AAT – on which construction was just beginning in the venerable telescope-building works of Sir Howard Grubb, Parsons & Company at Newcastle upon Tyne, England. I could hardly have guessed that by the 1990s I’d be managing the same telescope’s scientific output as its Astronomer-in-Charge, and that in far-distant 2024 I’d be helping celebrate half a century of ground-breaking AAT discovery as the Australian Government’s Astronomer-at-Large.

THE GENESIS OF THE AAT goes back much further than 1969. In the late 1950s the new science of radioastronomy was experiencing significant infrastructure investment in both the UK and Australia – think observatories in Jodrell Bank, England, and Parkes, New South Wales. It was Richard Woolley, then at Mount Stromlo Observatory in Canberra and subsequently Britain’s 11th Astronomer Royal, who floated the idea of a large, jointly funded visible-light telescope in the Southern Hemisphere to allow optical astronomers in both countries to keep up with their radio colleagues.