The explosion was easily the most studied event in the history of astronomy, with 3674 researchers from 953 institutions collaborating on a single paper summarizing the merger and its aftermath.
The observations bolstered the 25-year-old hypothesis that neutron-star mergers produce short gamma ray bursts.
That first observation of a neutron-star merger, and the scientific bounty it revealed, is ’s 2017 Breakthrough of the Year.
Especially remarkable was the way the event was spotted: by detecting the infinitesimal ripples in space itself, called gravitational waves, that the spiraling neutron stars radiated before they merged.
The gravitational waves from the twirling neutron stars tickled not only the enormous LIGO detectors in Hanford, Washington, and Livingston, Louisiana, but also the French-Italian Virgo detector near Pisa, Italy, which, after a 5-year upgrade, had started recording data just 17 days earlier.
Researchers immediately knew they were witnessing the death spiral of two neutron stars.
They would also like to see the gravitational waves right up to the point at which the neutron stars spiral into each other.
In this first observation, the LIGO and Virgo detectors tracked the stars whirling around each other at an accelerating pace, sending out higher and higher frequency gravitational waves.Over several days, the source faded from bright blue to dimmer red.Then, after 11 days, it began to glow in x-rays and radio waves.But at about 500 cycles per second, the waves’ frequency climbed out of LIGO’s sensitivity range, and the detectors couldn’t observe the final few revolutions leading up to the merger.Those final revolutions could provide insights into the nature of neutron stars, orbs of pure nuclear matter slightly more massive than the sun but just 20 to 30 kilometers wide.Scientists first detected such waves just 27 months ago, when the Laser Interferometer Gravitational-Wave Observatory (LIGO) sensed a space tremor from two massive black holes spiraling together in an invisible cataclysm.