An Australian scientist predicts the detection of two stars colliding 500 million years ago is just the beginning of what can be found by upgraded "discovery machines" that can see further into space.
The international team hunting for gravitational waves - ripples in space and time - hope they may even discover a never-before-seen event: a black hole swallowing a neutron star.
The collision of two neutron stars was detected on April 25 using arguably the most sensitive scientific instruments ever built, which have also discovered a number of black hole mergers.
The twin US detectors of the Laser Interferometer Gravitational-Wave Observatory (LIGO) only restarted their search on April 1 after a series of upgrades.
The Australian National University's Professor Susan Scott said the latest achievement using the upgraded gravitational-wave detectors, which she labelled discovery machines, was just the beginning.
"With the improved sensitivity of the detectors during our year of downtime, we have achieved the second detection of two neutron stars smashing into each other - this time in less than one month of observing time," she said on Friday.
"We expect to detect gravitational waves from lots more cataclysmic events - including those we've never detected before such as a black hole swallowing a neutron star and nearby exploding stars, which produce much fainter signals."
Prof Scott said astronomers had to scan a very large area of the sky in search for the latest star collision as one of the LIGO detectors was briefly offline at the critical moment.
She said the upgraded European-based gravitational-wave detector called Virgo also picked up a signal from the collision, but it was very weak.
Prof Scott said the ANU led efforts to locate the neutron star collision by scanning a massive region of the southern sky for bright light from the explosion with the SkyMapper telescope in central NSW.
The upgrades that improved the range and precision of the LIGO detectors included the installation of ANU-designed 'quantum squeezers', which the university's Dr Terry McRae explained dampen quantum noise that can drown out weak gravitational-wave signals.
"With these improvements, the LIGO detectors can see much further into the universe and detect many more gravitational-wave signals," Dr McRae said.
Australian Associated Press