Spaghettification — it may sound like a cartoon wizard’s spell effect but it’s actually a term scientists use for what happens to massive objects that get too close to a black hole…they’re literally pulled apart into long strands of material by the black hole’s immense gravity. “Massive objects” can mean planets, asteroids, spaceships, or even stars like our Sun, and recently astronomers have caught a rare glimpse of one of the latter experiencing such a drawn-out demise in a galaxy 215 million light-years away.
Spaghettification is a fun nickname for a tidal disruption event which, were it to happen to you or the spacecraft you happened to be traveling in, would not be very fun at all. For decades a staple of the weird physics hypothesized to exist near the event horizons of black holes, spaghettification happens simply because the gravitational pull experienced on the side of an object closest to the black hole are vastly and increasingly stronger than on the side further away from it, and this tidal discrepancy pulls massive objects apart down to the smallest levels.
From a European Southern Observatory news release on October 12, 2020:
“When an unlucky star wanders too close to a supermassive black hole in the centre of a galaxy, the extreme gravitational pull of the black hole shreds the star into thin streams of material,” explains study author Thomas Wevers, an ESO Fellow in Santiago, Chile, who was at the Institute of Astronomy, University of Cambridge, UK, when he conducted the work. As some of the thin strands of stellar material fall into the black hole during this spaghettification process, a bright flare of energy is released, which astronomers can detect.
Although powerful and bright, up to now astronomers have had trouble investigating this burst of light, which is often obscured by a curtain of dust and debris. Only now have astronomers been able to shed light on the origin of this curtain.
“We found that, when a black hole devours a star, it can launch a powerful blast of material outwards that obstructs our view,” explains Samantha Oates, also at the University of Birmingham. This happens because the energy released as the black hole eats up stellar material propels the star’s debris outwards.
“The observations showed that the star had roughly the same mass as our own Sun, and that it lost about half of that to the monster black hole, which is over a million times more massive.”Matt Nicholl, Royal Astronomical Society research fellow at the University of Birmingham, UK, lead author
The discovery was possible because the tidal disruption event the team studied, AT2019qiz, was found just a short time after the star was ripped apart. “Because we caught it early, we could actually see the curtain of dust and debris being drawn up as the black hole launched a powerful outflow of material with velocities up to 10,000 km/s,” says Kate Alexander, NASA Einstein Fellow at Northwestern University in the U.S. [Editor’s note: that’s over 22.3 million miles per hour!] “This unique ‘peek behind the curtain’ provided the first opportunity to pinpoint the origin of the obscuring material and follow in real time how it engulfs the black hole.”
Read more about this from ESO here, and watch a summary of these findings below:
Main image credit: ESO/M. Kornmesser