A streak of light may not be a black hole fleeing its galaxy after all

A trail of starlight thought to possibly indicate a runaway supermassive black hole may be something much more mundane: a spiral galaxy seen edge on, a new study finds.

In February, astronomer Pieter van Dokkum of Yale University and colleagues reported spotting a line of stars near a compact galaxy in Hubble Space Telescope images. The researchers’ analysis suggested that three galaxies had interacted and merged, kicking a supermassive black hole out of its host galaxy (SN: 3/10/23). The black hole then traveled through a nearby gas cloud, the scenario goes, triggering the formation of stars in a line that points toward the home galaxy and revealing the black hole’s madcap escape.