The most energetic, luminous, and long-lasting transient celestial event known has been observed by astronomers. A supermassive black hole in a distant galaxy has ripped apart a star, turning it into a long bright stream of plasma – a process called spaghettification. The automatic survey gave the event the name ZTF20abrbeie and earned the nickname "Scary Barbie" as it was just so terrifyingly powerful.
“It's absurd. If you take a typical supernova and multiply it a thousand times, we're still not at how bright this is – and supernovas are among the most luminous objects in the sky,” senior author Professor Danny Milisavljevic, from Purdue University’s College of Science, said in a statement. “This is the most energetic phenomenon I have ever encountered.”
Transient events in astronomy tend to last very little time – from a fraction of a second to a few months, things appear and then vanish again. These are not long-drawn processes. A tidal disruption event such as this usually happens on a much shorter time scale, but in this extreme case, the event has been going for 800 days already and it might not stop for a while.
“We think a very supermassive black hole pulled in a star and ripped it apart,” explained lead author Bhagya Subrayan, also from Purdue. “The forces around a black hole, called tidal disruption, pull other objects apart in a process called ‘spaghettification.’ We think that’s what happened, but on extreme time scales: The most massive of black holes ripping apart a massive star. The duration is unlike anything we’ve ever seen before, and it produced the most luminous transient in the universe.”
The supermassive black hole has an estimated mass of 100 million times the mass of our Sun, and the star is estimated to weigh 14 times our Sun. The light of this event traveled 7.8 billion years before reaching the Zwicky Transient Facility, which uses the Palomar Observatory in California. The team continues to monitor this event to better understand how tidal disruption events are.
“There are few things in the universe that can be so powerful, reactions that can be this long-lived,” Milisavljevic said. “Discoveries like this really open our eyes to the fact that we are still uncovering mysteries and exploring wonders in the universe – things no one has ever seen before.”