New instruments lead to new questions
As new international instruments for studying the Universe have started operations, they have been able to observe explosive cosmic events as they happen.
These instruments include Square Kilometre Array precursors that operate at low radio frequencies, including our own ASKAP radio telescope at Inyarrimanha Ilgari Bundara, our Murchison Radio-astronomy Observatory, and the Advanced LIGO and Virgo instruments designed to detect gravitational waves. However, observations with these new tools don't always reveal the whole picture.
Rapid follow-up with complementary instruments
Data from telescopes tuned to different parts of the electromagnetic spectrum can be combined to reveal a more complete understanding of these mysterious events.
By quickly turning our Australia Telescope Compact Array to follow-up these short-lived and variable events we've enabled new insights into the physics of extreme objects such as black holes and merging neutron stars.
Located on Gomeroi Country near Narrabri in NSW, the Compact Array is made up of six 22-metre dishes working together as a single instrument. The telescope operates across a wide frequency range, which makes it ideal for doing follow-up studies of objects discovered by other instruments.
The telescope has another important feature: a fast, automatic override response that allows it to interrupt scheduled observing if an alert is generated by another telescope. Within seconds, it can move to a new target and start observing.
In 2017, our partners at The University of Sydney worked closely with our team to use the Compact Array to follow-up the Advanced LIGO instrument's ground-breaking detection of gravitational waves from two merging neutron stars.
Verifying the results obtained from another radio telescope, the Very Large Array in the US, the Compact Array confirmed that this was the first time radio waves had ever been detected from a gravitational wave event.
Another team led by researchers at Macquarie University and Western Sydney University recently used the Compact Array to look at a nova explosion in the southern constellation of Carina.
While other instruments found a series of shock-generated flares appearing simultaneously in the gamma-ray and optical parts of the electromagnetic spectrum, the team used the Compact Array to show that long after the nova had faded from view at these wavelengths more shocks were still being generated at radio frequencies.
Maintaining Australia's leadership in radio astronomy
After the Second World War our scientists and engineers were among the pioneers of radio astronomy.
Over coming years, rapid follow-up to transient events using the Compact Array will enable us to learn more about how the Universe works on shorter timescales and maintain Australia's leadership in important new areas of astronomy.