A neutron-star crash spotted 3 years ago is still pumping out X-rays. But why?

Three years ago, two neutron stars collided in a cataclysmic crash, the first such merger ever observed directly. Naturally, scientists kept their eye on it — and now, something strange is happening.

Astrophysicists observed the star collision on Aug. 17, 2017, spotting for the first time ever signs of the same event in both a gravitational-wave chirp detected by the Laser Interferometer Gravitational-Wave Observatory (LIGO) on Earth and a massive burst of different flavors of light. The X-rays observed at the location 130 million light-years from Earth peaked less than six months after the merger’s discovery, then began to fade. But in observations gathered this year, that trend has stopped, and an X-ray signal is unexpectedly lingering, according to research presented on Thursday (Jan. 14) at the 237th meeting of the American Astronomical Society, held virtually due to the pandemic.

Source link