Anglo-Australian Telescope

Commissioned way back in 1974, the Anglo-Australian Telescope was one of the last 4 metre equatorially mounted telescopes to be constructed. Such telescopes are tilted to align with the rotation of the Earth, and follow or track a star through the sky they only have to move in one direction. Most modern large telescopes have to move in two directions to follow a star - a more complicated technique but possible these days with the advent of modern computers.

Its excellent optics, exceptional mechanical stability and precision computer control make it one of the finest 4-m telescopes in the world.

Anglo-Australian Telescope
Credit: AAT
Some facts about the telescope:
  • Observatory location: Siding Spring Mountain, Australia
  • Height above sea level: 1,130 metres (3,700 feet)
  • Moving Mass: 120 metric tonnes
  • Mirror diameter: 3.9 metres

The Observatory was established at Siding Spring (New South Wales) to take advantage of the extremely dark skies. Siding Spring is located around 500 km to the north-west of Sydney, Australia.

The telescope provides the opportunity for astronomers to observe the southern sky where some of the most exciting objects are found, including the centre of our own Milky Way Galaxy and our galactic neighbours, the Magellanic Clouds.

Horsehead Nebula
Credit: AAT

Because of the wide field of view, the AAT has been responsible for taking some of the most stunning pictures of the heavens, pictures which have appeared in countless books and posters throughout the world.

This spectacular image shows a wide view of the Horsehead Nebula; a massive region (or cloud) of dust and gas which is currently providing material for the birth of lots of new stars. These 'baby' stars start off very hot and are lighting up the cloud just below the brightest star in the centre of the picture.