The night sky above the Mid-Murray of South Australia is so dark it could become a protected reserve for stargazers around the world.

Far enough from the light pollution of Adelaide that on a clear, moonless night you can see 'into infinity', the region is hoping to be declared the state's first dark sky reserve.

Mid-Murray Council and Mid-Murray Landcare Group is working with SA astronomy groups to preserve its night sky after early testing showed near total darkness.

"It's almost as dark as it can get," said Adelaide amateur astronomer Andrew Cool, who measured the darkness to be 21.97 on a darkness scale of 0-22, where 22 is complete darkness.

When it is that dark, you can see everything — as long as you look up.

"Infinity, that's the best way of putting it," Mr Cool said.

"It's mind-boggling compared to what I see in the city, where you might be lucky to see the 2,000 or 3,000 brighter stars.

"[In the Mid-Murray], you literally see the whole galaxy."

Protecting the night from light pollution

Only 35 dark sky reserves exist around the world, including one at Warrumbungle National Park in NSW.

The reserves are declared by the International Dark-Sky Association to protect the night sky from light pollution.

Light pollution from street lamps and buildings disrupts ecosystems, disorientating turtle hatchlings and migrating birds and nocturnal hunting and reproduction.

The mallee landscape in the Mid Murray provides ideal campsites for astronomy enthusiasts. ( Supplied: Chris Tugwell )

Mid-Murray Landcare Group vice-chair Chris Tugwell said a reserve was the equivalent of a World Heritage listing for the sky.

"In the northern hemisphere, there are cities where people can't see the stars at all, they can't see the moon [because of artificial light pollution]," Mr Tugwell said.

"This is something that can bring people here, they can come and see the sky in a way they have never experienced it."

Mr Tugwell said the intent was to create a dark sky trail linking conservation parks and local parks in an area between Cambrai and Sunnydale.

Its relative proximity to Adelaide of about 120 kilometres — less than a two-hour drive — would be a major drawcard.

"Many dark sky-accredited sites are in remote and hard-to-reach places across the world where people can set up their own campsites, bring their own gear and admire the sky," Mr Tugwell said.

Adelaide astronomer Andrew Cool set up camp at a site near Yookamurra Sanctuary in the Mid Murray to measure the darkness of the sky. ( Supplied: Andrew Cool )

Engaging community and volunteers

The next step is to engage community volunteers to measure the darkness of the Mid-Murray night sky, carried out with a sky quality metre.

"It's a light sensor. You press a button and it waits for a certain number of seconds until it's received a certain number of photons from the sky and then it pops up a digital reading," Mr Cool explained.

He said he had taken readings from a site near Yookamurra Sanctuary near Sedan.

"Here in the city, with the naked eye you might get down to what we call a magnitude four star, so you can barely barely see the Milky Way, even in the darkest part of the night," Mr Cool said.

"In a dark site like the Mid-Murray area, you can see down to magnitude six, possibly magnitude seven.

"That's about 10 times as faint that you can see in the Mid-Mallee compared to the city.

"I sit in a paddock populated with wombat burrows and feral goats and god knows what else, sitting by myself, and I'm insignificant."