Parramatta Observatory

Sydney Observatory is located on a hill now known as Observatory Hill in the centre of Sydney. The site evolved from a fort built on 'Windmill Hill' in the early 19th century to an astronomical observatory during the nineteenth century. It is now a working museum where evening visitors can observe the stars and planets through a modern 40 cm Schmidt-Cassegrain telescope and a historic 29 cm refractor telescope built in 1874, the oldest telescope in Australia in regular use.

In 1797, early on during the European settlement of New South Wales, Australia, a windmill was built on the hill above the first settlement. Within ten years the windmill had deteriorated to the point of being useless; the canvas sails were stolen, a storm damaged the machinery, and already by 1800 the foundations were giving way. The name of Millers Point remembers this early land use.

In 1803, Fort Philip was built on the site under the direction of Governor Hunter to defend the new settlement against a possible attack by the French and also from rebellious convicts. The fort was never required to be used for any such purposes. In 1825 the eastern wall of the fort was converted to a signal station. Flags were used to send messages to ships in the harbour and to the signal station on the South Head of the harbour.

An early observatory was established in 1788 on Dawes Point, at the foot of Observatory Hill, in an ultimately unsuccessful attempt to observe in 1790 the return of a comet suggested by Edmond Halley of Halley's Comet fame. The Colony's second observatory was established at Parramatta in 1821 by Governor Sir Thomas Brisbane.

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Wikipedia