Telltale ripples in the fabric of spacetime have revealed the existence of a cosmic object that scientists can’t definitively classify.
Whatever it is, the object was engulfed suddenly by a black hole weighing 23.2 times the mass of our sun, 800 million light-years away. The gravitational waves thrown off by that violent merger were picked up last August by the twin detectors of the Laser Interferometer Gravitational-Wave Observatory, or LIGO, and by the Virgo gravitational-wave detector in Italy.
The gravitational-wave patterns revealed that the smaller object was 2.6 times as massive as our sun. And that’s where the classification problem arises.
