Perry Vlahos, president of the 1300-member astronomical society, says the reality is the plan will ruin what was once the centrepiece of science in Victoria.
The master plan proposes landscaping around the observatory to turn it into a “fully serviced” performance space.
The car park, roadway and fences near the observatory will be removed to return it to «public open space», while paths will be reworked.
“Making it into a venue that is going to be able to accommodate 5000 people, it’s basically going to be trashing the joint,” Mr Vlahos said.
“They will need to have external lighting. They will need pavements. All these elements are incompatible with what telescopes need to function at their optimum.”
Paved areas are a particular problem for astronomy. During the day they heat up and at night they release that heat into the air, causing currents in the atmosphere which can interfere with observations.
The observatory was founded in 1862 and sits to the east of the Shrine of Remembrance. It made all the weather forecasts for colonial Melbourne and played an important role in several major scientific projects.
They are just thinking of the observatory as part of the gardens. And it never has been.
But light pollution from a growing city slowly ruined the view of the heavens and since 1945 it has not been used in a professional capacity. It still contains three telescopes in regular use by the astronomical society and the public. The society has also spent years painstakingly restoring the historic and huge Great Melbourne Telescope, planned to be re-installed soon.
Mr Vlahos said control of the observatory was handed to the gardens in 1992, and since then the gardens had been slowly taking over the space. He said the program of temporary garden events, including a circus, damaged the observatory lawns.
Flood-lighting for those events also ruined the darkness needed for observations. A recent renovation saw many historically important parts of the observatory bulldozed and replaced with a cafe, shop and car park, Mr Vlahos said.
“They are just thinking of the observatory as part of the gardens. And it never has been. They don’t have the right to be disrespectful to its borders or its prime activities,” he said.
But gardens’ management told The Age the society’s criticism was surprising.
Gardens CEO Tim Entwisle said parts of the plan had already been presented to the astronomers some months ago. At the time, he said they had provided cautious support.
The space was already used for events of up to 5000 people, and any changes would be “back room”. No permanent lighting would be added.
“We’re going to landscape the whole area and create an open landscape near those buildings,» he said. «It’s certainly very positive for the observatory and these are changes which are long overdue.
“Those buildings have been closed off to the public and now we can bring people in to appreciate not only historical astronomy but also some of the great advances being made today.”
The plan decreased the number of paved areas and increased greenery, Mr Entwisle said.
“I’m a bit surprised by the criticism. I’m quite excited as the director of the gardens to be looking after the observatory and have these plans for it,» he said.
“I am keen to promote that we go from plants to planets, and this is an opportunity to do that.”
Liam is The Age and Sydney Morning Herald’s science reporter