Back in 2022, astronomers were puzzled by a so-called “tidal disruption event” (TDE), dubbed AT2018hyz, that had faded when it was first noticed three years earlier, only to unexpectedly reanimate and burp out extremely bright radio waves. University of Oregon astrophysicist Yvette Cendes, a co-author of that 2022 paper, dubbed the black hole “Jetty McJetface” (a nod to the 2016 online British competition to name a research vessel Boaty McBoatface).
Astronomers have continued to monitor it ever since. Far from fading again, the TDE has grown 50 times brighter, and that brightness continues to increase. The black hole’s energy emission might not peak until 2027, according to a new paper published in the Astrophysical Journal.
As we’ve previously discussed, it’s a popular misconception that black holes behave like cosmic vacuum cleaners, ravenously sucking up any matter in their surroundings. In reality, only stuff that passes beyond the event horizon—including light—is swallowed up and can’t escape, although black holes are also messy eaters. That means that part of an object’s matter is actually ejected out in a powerful jet.
In a TDE, a star is shredded (or “spaghettified”) by the powerful gravitational forces of a black hole outside the event horizon, and part of the star’s original mass is ejected violently outward. This, in turn, can form a rotating ring of matter (aka an accretion disk) around the black hole that emits powerful X-rays and visible light. The jets are one way astronomers can indirectly infer the presence of a black hole. Those outflow emissions typically occur soon after the TDE.