A high-tech telescope situated in Western Australia's desert has discovered a galaxy almost five billion light-years away.

Six satellite dishes in a radio-quiet patch of WA's Murchison region have detected a faint signal from a galaxy formed billions of years ago, before the birth of the solar system.

The satellites form part of the Australian Square Kilometre Array Pathfinder (ASKAP) project, which is being built on a pastoral station almost 400 kilometres from Geraldton.

CSIRO head of astrophysics Simon Johnston said he expected other groundbreaking discoveries to be made once another 30 satellites come online next year.

"This is kind of the tip of the iceberg of what we're going to find," Dr Johnston said.

"Eventually we'll find thousands of these things, and the idea is to study the evolution of gas through the whole age of the universe.

"How did galaxies form, how did they change and how did they become the galaxies we see today?"

Dr Johnston said the discovery gave him confidence that ASKAP would be able to detect galaxies invisible to other telescopes.

"This is one of the furthest distances to which [a signal] has been detected, so we're very excited about this result," he said.

He says the Murchison region is the most radio quiet site in the world to conduct astronomy work.

"The desert environment is exactly what we need, we want to be as far away from humans as possible," Dr Johnston said.

"Most places in the world you couldn't detect this signal, because everybody's using their mobile phone and it blocks out all signals.

"There's a lot of radio signals going around that swamp out our tiny little signals from these distant galaxies.

"We're very excited about this result because it shows the potential of this site to really do excellent science."

The discovery is due to be announced at a National Astronomy Meeting in the UK.