Telescopes at a global astronomy research hub appear to have survived a devastating Australian bushfire that destroyed nearby homes and damaged several buildings on the site, officials said on Monday.

The fire, which raged through the night fuelled by hot, strong winds, damaged parts of the Aus$100 million (US$105 million) Siding Spring Observatory some 500 kilometres (330 miles) northwest of Sydney, officials said.

But the New South Wales Rural Fire Service (RFS) said although some 33 homes had been destroyed, aerial surveillance had established that the main Anglo-Australian Telescope (AAT) "has survived, although it is not known if it has been damaged".

Eighteen staff working at the observatory, which houses 10 telescopes run by Australian, Polish, British, South Korean and American researchers, were safely evacuated before the fire struck.

Monitoring instruments at the main telescope showed temperatures surging above 100 degrees Celsius (212 Fahrenheit) at the height of the danger, and the RFS said there had been "genuine fear for people's lives".

The inferno was one of 170 blazes raging on Monday across New South Wales, Australia's most populous state, where heatwave conditions have scorched some 500,000 hectares (1.235 million acres) over the past week.

The Australian National University, which administers the remote observatory site, said five buildings had been "severely affected or damaged", including lodgings for visiting researchers and the visitors' centre.

"An initial visual assessment indicated that no telescopes appear to have received major damage, but the impact of the fire on the instruments will not be known until a technical inspection of the telescopes can be done when the site is safe," the university said in a statement.

Acting Australian Astronomical Observatory director Andrew Hopkins said it was a great relief for researchers to see that the telescopes appeared intact, after bushfires destroyed a partner observatory in Canberra in 2003.

Five telescopes and surrounding buildings were razed when wildfires ripped through the Mount Stromlo facility, forcing the termination of a number of major projects including a digital survey of the Southern Hemisphere's skies.

"The significance of the site is absolutely huge," said Hopkins of Siding Spring.

"The Siding Spring Observatory site is the premier astronomical observatory facility in Australia for optical and infrared observing."

Researcher Rob McNaught was among many site staff who lived nearby and were forced to flee the "massive" smoke plume.

"Many hold fears that their houses are lost," he said. "We heard a lot of hair-raising stories from the last few to drive down the (access) road as it became engulfed in flames."

He said the four-metre AAT, one of the world's top telescopes and a key instrument in exploring the Milky Way and Magellanic Clouds, should be unaffected as it is a very secure and well defended facility.

The Australian wildfires began earlier this month in the southern state of Tasmania, where more than 100 homes were razed.

A firefighter died in Tasmania on Sunday while carrying out controlled burning. He was found dead about three kilometres from the main fire front, but the cause of death was not immediately known.

In another incident, a father and son were arrested by police on Sunday after they allegedly set fire to their drug manufacturing lab in bushland to destroy it, sparking a major fire in the Blue Mountains west of Sydney.