Xinwen Shu

The flare AT2018cqh in a dwarf galaxy turned out to be the trail of a star torn apart by a middleweight black hole. These objects are the missing link between tiny and giant black holes, and they are extremely hard to find. This discovery offers a new way to hunt for the invisible.

A single neutrino, caught by an Antarctic telescope, coincided with a flare from a star being torn apart by a black hole. The discovery showed that such catastrophes give birth to ghost particles. Now we know one of the sources of cosmic neutrinos.