Stawell mine could hold key to finding dark matter, scientists say
It is one of the most mysterious substances in the universe, and now a deep gold mine in Victoria might hold the key to finding it.
Dark matter is invisible and believed to be about 85 per cent of what makes up the universe, but it is all still a theory.
Its presence is merely inferred from its gravitational effects on visible matter, radiation, and the large-scale structure of the universe.
But a team of international scientists believes the characteristics of a mine in Stawell, north-east of Melbourne, could provide the perfect workplace environment to detect it.
The scientists, from Australia, Italy and the US, are collaborating in the development of sensitive crystals capable of measuring very tiny signals that might come from dark matter.
Professor Geoffrey Taylor, a physicist from the University of Melbourne, said the new equipment needed to be deep underground as the rock would shield any incoming signal from natural cosmic rays.
"So this is down at about 1,000 metres or even deeper and all these cosmic rays, which would be a background to a very sensitive measurement, have been filtered out by the rocks, they've been stopped by going deep enough," he said.
Unused deep mining sites present opportunity
The Stawell site also has another important feature.
"The activity of the mine is slowing down," Professor Taylor said.
"Deep mining has ceased and they're re-mining some of the material further to the surface so it makes sense to make use of this while the mining company is there and the deep areas are available to us."
Professor Taylor said the project was gaining momentum with strong international support and an advance team had begun making initial preparations at the potential site.
"We have some regional development money through the State and Federal governments that we're hoping for," he said.
"It's not in the bag yet but it's looking like we have a good opportunity for it to be funded at least to get it off the ground."
Scientists involved in the project are attending this week's Australian Institute of Physics Congress in Canberra.
Among them is particle physicist and Harvard University professor Lisa Randall.
She said some projects were being conducted in the northern hemisphere, but an observatory in the southern hemisphere would eventually be crucial to its success.
"You want to be able to track the dark matter over a period of time and in different regions of the world because you would see it differently and be able to distinguish dark matter from the background," she said.
"Doing a complimentary experiment here in the southern hemisphere would be an extremely exciting development."
