Sydney Observatory manager Marnie Ogg wants a little pocket of darkness in the city so people can see the night sky. Credit:James Brickwood The NSW Department of Planning no longer regards the observatory as primarily about science, but more for recreation and education. The department's Barangaroo​ concept said "the obstruction of a number of constellation viewable from Sydney Observatory for a portion of the year is acceptable". "We can still see the Southern Cross with the naked eye," Ms Ogg said. "But that's beginning to fade and we sometimes call it the Southern Triangle when only three stars are visible." While most dark sky parks around the world are in remote areas, Ms Ogg said the observatory would like to establish Australia's first urban park dedicated to the night sky. "We're all for Vivid. But we also think there is a way to do lighting in the city without throwing so much into the sky."

Professor Fred Watson, astronomer-in-charge, Australian Astronomical Observatory, Siding Spring, NSW. Credit:James Gilbert/AAO She hopes a review of Standards Australia AS 4282 on obtrusive lighting will assist reduce light pollution in the city. Ms Ogg said she was a pragmatist and already works closely with the City of Sydney and Barangaroo​ to minimise light spilling onto the observatory. Comparing light in the night sky at AAO's Siding Spring Observatory. Credit:AAO A spokesman for the NSW Department of Planning said: "Establishing an urban dark sky park at Observatory Hill ... would need to be investigated further by the Sydney Observatory."

Ms Ogg said recognising Observatory Hill as a dark sanctuary in a brightly lit city would be of benefit to the "night-time economy". "People really enjoy coming up here and being in the dark," she said. "Last weekend on our open days we had 1000 people a night visit us." Australia got its first dark sky park last year at the Warrumbungle National Park, adjacent to the Australian Astronomical Observatory at Siding Spring, Australia's largest optical telescope. Developments within 200 kilometres of the park must adhere to planning guidelines on lighting to minimise impact on the observatory. The astronomer-in-charge at Siding Spring is Professor Fred Watson.

"We don't want to stop people having fun at night," he said. "Astronomers don't want to make places dark and dingy, we just want them properly lit." Comparing light in the night sky at AAO's Siding Spring Observatory with light in Leichhardt. Professor Watson sits on the committee reviewing AS 4282, which controls obtrusive light. It was last published in 1997. He is hopeful Standards Australia will recommend more low-impact LED lighting, require fittings with zero upward lights and ensure other standards that stop this "upspill" and light pollution. Standards Australia will release a draft of the new standards this year. "If we had universal adoption of LED lighting properly controlled, you are saving significant upward light spill. Ultimately we could get a 30 to 50 per cent reduction in this sort of light pollution," he said.

He also pointed out that this could help save money and reduce carbon emissions. Professor Watson took part in Vivid Sydney and last weekend spoke at Byron Bay's inaugural Star Stuff astronomy festival. "From Siding Spring you can see Sydney throwing up its beige glow," he told the sold-out audience at Star Stuff. "Increased blobs of light will eventually damage the night sky of Siding Spring." Professor Watson said the dark sky movement wasn't only concerned about astronomy.

"Light pollution affects migrating birds that fly into illuminated buildings; loggerhead turtle hatchlings that navigate by a lit horizon are confused by too much light," he said. Professor Watson also said there were direct physical effects from light pollution: glare compromises road safety and a lack of darkness affects sleep patterns, leading to poor melatonin secretion. "We are in danger of losing the night sky in cities. We've lost the intimacy with the sky that we all would have had 100 years ago." [Fairfax Media attended Star Stuff in Byron Bay courtesy of the organisers and Elements of Byron. What is a Dark Sky Park?

According to the International Dark-sky Association, a Dark Sky Park is land possessing an exceptional or distinguished quality of starry nights and a nocturnal environment that is specifically protected for its scientific, natural, educational, cultural heritage, and/or public enjoyment. Most Dark Sky Parks are in remote locations, such as Australia's Warrumbungles or Death Valley National Park in the US. The city of Victoria in British Columbia has an urban star park at Cattle Point. Dark Sky Parks co-operate with surrounding communities to minimise light pollution and encourage tourism. As well as benefiting astronomers, dark skies can reduce carbon emissions and energy costs and assist migrating birds and other animals that navigate using natural light. According to Professor Watson, in the US alone $US3.3 billion ($4.3 billion) is wasted on unnecessary upward spill light a year, accounting for 21 million tonnes of carbon dioxide emissions.