Ancient star-crash detection ushers new dawn for space discovery

Published in the Research School of Physics Event Horizon
Vol44 Issue18 6–10 May 2019

Ancient star-crash detection ushers new dawn for space discovery

An international team of scientists, including from RSPE's Centre for Gravitational Physics, have detected two stars colliding in space about 500 million years ago. The discovery comes just weeks after the restarting of the most sensitive scientific instrument ever built – the Advanced Laser Interferometer Gravitational-wave Observatory (LIGO) – which comprises twin detectors in the United States.

This is the first time such an event has been witnessed since the detectors were taken offline for upgrades to improve their range and precision, and promises a new dawn for space discovery. On 25 April 2019, one of the LIGO machines detected the ripples in space and time from the collision of two neutron stars, which are the densest stars in the Universe – they have an average radius of 15 kilometres and are twice the mass of our Sun. The neutron star collision occurred about 4,750 million trillion kilometres away from Earth – a distance which equates to 500 million light years. 

ANU's media release: https://www.anu.edu.au/news/all-news/ancient-star-crash-detection-ushers-new-dawn-for-discovery

LIGO's media release: https://www.abc.net.au/news/science/2019-05-03/gravitational-waves-neutron-stars-black-hole-ligo/11054822

Caption: 

Left: Dr Christopher Onken from RSAA and Prof. Susan Scott from RSPE (image credit: ANU media office), Right: Dr Terry McRae and PhD Student Nutsinee Kijbunchoo from RSPE at LIGO (image credit: N Kijbunchoo).