The Australian Astronomical Observatory (AAO), formerly the Anglo-Australian Observatory, is an optical/near-infrared astronomy observatory with its headquarters in Marsfield in suburban Sydney, Australia. Originally funded jointly by the United Kingdom and Australian governments, it is now managed wholly by Australia's Department of Industry, Innovation, Science, Research and Tertiary Education. The AAO operates the 3.9-metre Anglo-Australian Telescope (AAT) and 1.2-metre UK Schmidt Telescope (UKST) at Siding Spring Observatory, located near the town of Coonabarabran, Australia.