Mysterious X-rays could be kilonova “afterglow” from 2017 neutron star merger - Ars Technica

This would mean the two stars "spun down" for a second before collapsing into black hole

Enlarge/ Artist's representation of the merger of two neutron stars to form a black hole (hidden within bright bulge at center of image). The merger generates opposing, high-energy jets of material (… [+6372 chars]

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