Astrophysicists at WA’s Zadko telescope had just learned about the detection of a monumental deep space event involving two neutron stars colliding — which they had been hoping to find for years — when they came under sustained cyber attack.
At the critical and fleeting moment, they could not move their telescope to track the gigantic explosion 130 million light years away.
The first signs of the neutron star merger had been detected at 8:41am (WST) on August 31 by the LIGO observatory in the United States.
It had picked up a gravitational wave signal — tiny ripples in the fabric of space-time — emitting from the collision.
Vital opportunity to capture event
They sent out an alert to observatories around the world to hone in and look for other signals.
Astrophysicist Professor David Coward, from the University of Western Australia’s Australian International Gravitational Research Centre at Gingin, north of Perth, said two seconds after the gravitational waves were detected there was a gamma ray burst.
It was the first time gravitational waves had been observed coming from two neutron stars colliding, rather than from black holes.
Professor Coward said it was also the closest scientists had seen a gravitational wave signal, one of the closest they had seen a gamma ray burst, and the first time a ‘kilonova’ had been seen.
A kilonova is when some of the debris from a neutron star merger undergoes a slow nuclear reaction and produces heavy elements like gold, including all the gold found on Earth.
“So we’re intimately connected with binary neutron star mergers,” Professor Coward said.
“We’re wearing the fossils of binary neutron star mergers.”
Virus infiltrates central server
The team at Gingin had thought they would never witness an event like this in their lifetime. And now it was occurring, they swung into action to help track it as it came in and out of range for observatories around the world.
“Our opportunity to capture this event was critical,” Professor Coward said.
They put a new schedule in the telescope, but it would not respond. They had been hacked.
Their computers were infected with viruses infiltrating their hardware, especially their central server. It meant they could not properly use the robotics system at the remote facility, 67 kilometres north of Perth.
‘We did that and sure enough it was a miracle’
Technical experts were rushed out to the site from UWA and worked non-stop to get the computers back online and protect them from the cyber attack.
But by the time they had, it was Saturday and two whole days had passed since the neutron star merger had first been detected.
“In our wildest dreams we didn’t imagine that we would actually see anything, capture the image, because it was fading,” Professor Coward said.
“But remarkably we did get images on the second night.”
There were more anxious moments to come, though.
“To my dismay, I looked at the images and there was nothing there,” he said.
“But then my colleagues at Swinbourne University in France said, ‘Hold on a minute. The galaxy is obscuring the emission from the event, from the binary neutron star merger. Let’s take the galaxy light, subtract it off the image’.”
“We did that and sure enough it was a miracle. We had this beautiful, exquisite data, showing this kilonova explosion, this light coming from this kilonova explosion. And then we thought, ‘Wow. We’ve done it’.”
“So, we’ve got this beautiful, what we call, light curve showing the evolution of this explosion from the way the light changes in intensity over that time.
“Our data is going to be important because it fills in a time gap in the evolution of this explosion. You can imagine each point on the Earth has an opportunity to record this event uniquely at that time, where other locations can’t.”