For the first time, scientists have found conclusive evidence that short gamma ray burst, often observed by satellites, are indeed created by colliding neutron stars, something only speculated for decades. Joint observations have also given them an independent way of measuring the expansion rate of the universe.
Scientists associated with the US-based Laser Interferometer Gravitational-Wave Observatory described this as the beginning of gravitational-wave multi-messenger astronomy, tracing the beginning to August 17, 2017, when gravitational waves from a pair of colliding neutron stars were detected for the first time by LIGO and the Europe-based Virgo. The August 17 gravitational wave signal is the strongest detected so far, owing to the relatively close location, around 130 million light years from Earth, and was confirmed by several telescopes around the world. The near-simultaneous arrival of gravitational waves and gamma rays from a source 130 million light-years away confirms that gravitational waves indeed travel with the speed of light, as predicted by Einstein’s theory.
The joint observations showed signatures of newly synthesized elements in the wake of the collision, confirming that such mergers were the birthplace of half the elements heavier than iron, in cluding most of the gold and platinum, in the universe.