Imagine you've spent half a decade building satellites to study a little-known part of the Earth's atmosphere.

They're the first Australian-built satellites to go into space for more than a decade.

You watch them launch from Cape Canaveral in Florida with great fanfare.

They're deployed from the International Space Station in May.

Then … nothing. Radio silence.

Your efforts appear to have resulted in space junk — invisible, unresponsive bricks hurtling at 27,000km/hr, 400km above the Earth's surface.

But this is not a story about loss.

This is the remarkable tale of how a Dutch radio telescope, ham radio operators and engineers from the universities of New South Wales, Sydney and Australian National University brought two satellites back to life.

Failure at launch

Engineers from UNSW, USyd and ANU found the satellites and got them back under control. ( Supplied: Grant Turner, UNSW )

Thirty-six tiny 'cubesats', about the size of a loaf of bread, formed part of an international swarm launched earlier this year.

But shortly after their release, three of the satellites from Australian universities were unresponsive.

They were supposed to transmit a beacon to say "I'm working" — but they were silent — and engineers in Australia could only check twice a day, when the satellites passed over their ground stations.

The engineers thought it could have been a battery issue.

While the satellites had solar panels, they thought they could be trapped in a vicious loop whereby they did not have enough power to deploy the antennas, but were constantly trying to extend them with the little charge they had accumulated.

The teams wrote commands ready to upload — but because the tiny satellites antennas did not extend, they needed a much bigger telescope.

"It meant that we had to speak a lot louder to them for the satellites to hear us, so we needed much more powerful ground stations than what we had here at UNSW and in Canberra at the ANU," deputy director of the Australian Centre for Space Engineering Research (ACSER) Elias Aboutanios said.

Dr Aboutanios tried to use equipment from the Defence Department, Optus, CSIRO and NASA, but no facilities that could broadcast at the right frequencies were available.

Sydney … we have a problem

The cubesats being launched from the International Space Station. ( Supplied: UNSW )

Running out of options, a research associate from UNSW — Joon Wayn Cheong — used his amateur radio licence, calling for help from his worldwide network.

Incredibly, a Dutch sound technician responded — offering access to a 1950s-era restored 25-metre radio telescope.

"We had access to this old beautifully restored dish — the thing that would work for us — however, Jan [van Muijlwijk, the Dutch technician] works his nine-to-five job during the week, so he could only do this on Saturdays for us," Dr Aboutanious said.

Mr van Muijlwijk fired the commands — and miraculously, it worked.

But only for one of the cubesats.

"So we had to switch back to work out, is our satellite dead? Is it damaged? Is there another reason that we can't talk to it?" Dr Aboutanious said.

"We started wondering — is where we're pointing at the correct place?

"What happens is when these things start orbiting, they are tracked by NORAD (the North American Aerospace Defense Command).

"They track everything in the sky that is larger than a tennis ball … they tell us where they are in the sky."

So engineers continued to try to make contact with the other two satellites — again — getting nothing.

A Colorado mix-up

Engineers looking for the missing cubesats. ( Supplied: UNSW/Grant Turner )

It turns out NORAD had mislabelled their cubesat.

All along, the engineers were pointing the antenna and trying to detect signals in the wrong place.

Dr Aboutanious believes NORAD had mixed up the labelling of the cubesats with another team's.

As soon as the Dutch dish pointed to what the NORAD data said was the University of Colorado's cubesat, it detected a weak signal that was clearly from the UNSW satellite.

"We [sent our signals to the other cubesat] on the next weekend — next Saturday, we had to wait — we uploaded the commands and they worked," he said.

"I'm not so much relieved, more ecstatic is the better word.

"We're over the Moon — the whole team is just very, very happy."

One more to go

However, the third Australian university cubesat remains unresponsive — and the engineers who brought the first two back to life are ready to offer their services if needed.

Of the 28 cubesats deployed in May, eight are not working.

Those that are responsive will now undergo a testing process before being commissioned later this year.