Astronomers call it “spaghettification,” and it’s a bad idea: it happens when you venture too close to a black hole and fall into it. Tidal forces stretch you and break like a noodle, then your scraps orbits the black hole until they collide and smack each other.
On the flip side, the energy released by your long fall and the collision of your earlier atoms could create lightning – a cosmic pyre, if you will – that is visible throughout the universe.
In one case reported last weekIt was just an anonymous star in a galaxy far, far away that was about to end. Thanks to luck and the ever-increasing vigilance of the sky, the whole world watched the star go down.
“It was quite a feast in fact,” Matt Nicholl, an astrophysicist at the University of Birmingham in England, said in an email. He led a team of astronomers who described this stellar apocalypse in the Royal Astronomical Society’s monthly bulletin Monday.
“That black hole was a messy eater,” added Kate Alexander of Northwestern University and a member of Dr. Nicholl’s team was added in an email. In the end, she said, only about half the star was consumed by the black hole. The rest of its decayed material was blown outward into space at a breakneck speed of a few percent of the light.
The excitement began on September 19, 2019 when the Zwicky Transient Facility, a telescope on Palomar Mountain in California, and other sky surveillance networks in the constellation Eridanus discovered a torch at the center of a galaxy 215 million light years from Earth.
The torch bore the hallmarks of a tidal disruption event, the technical name for when a black hole tears a star to pieces and eats it.
Astronomers rushed to their ground-based and space-based telescopes to monitor AT2019qiz, as the torch was named. (“AT” stands for “astronomical transient”.)
Over the next few weeks the torch brightened quickly. At its peak, it emitted roughly a billion times as much energy as our sun. The torch slowly faded for the next five months.
The result was a unique and multi-dimensional look at the complexities of death from the black hole – based on radio emissions, X-rays and gamma rays, and old-fashioned observations with visible light.
Black holes are gravitational potholes in spacetime that are predicted by General Theory of Relativity, Albert Einstein’s Theory of Gravitation. They are so deep and dense that nothing can escape them, not even light. Our Milky Way Galaxy, and probably most of the galaxies, are littered with black holes that are formed when massive stars die and collapse. In addition, every galaxy seems to have its core An oversized version of one of those monsters, millions or billions of times as massive as the sun.
“We know that most galaxies have a supermassive black hole in their centers,” wrote Dr. Alexander in an email. “But we still don’t fully understand how these black holes got as big as they are or how they shaped their host galaxies.” Studying star disturbances could help understand how these black holes eat, grow, and interact with their surroundings.
The black hole in the Eridanus galaxy weighs about one million solar masses. As suggested by Dr. Nicholl and his team reconstructed that a star the size and mass of our own sun migrated into the center of the galaxy and got too close to the black hole – about 100 million miles.
That is roughly the distance from the earth to the sun. At this point the black hole’s gravitational pull exceeded the gravitational pull of the star’s core, and the star was “spaghettified” into a long stream around the hole. Eventually the current wrapped itself around the black hole and collided with itself. “Then the black hole started sucking it in,” said Dr. Nicholl.
He added, “If you could imagine the sun stretching into a thin stream and rushing towards us, the black hole has seen that.”
Astronomers have documented other such black hole Disruptions recentlyBut such events rarely occur so close to our own galaxy, and their internal dynamics are often obscured by dust and gas kicked up by the fatal collision. In this case, astronomers could see behind this curtain and determine that it was made up of pieces of the torn star.
“Because we figured it out early on, we were actually able to see the curtain of dust and dirt pull together as the black hole triggered a heavy drain,” said Dr. Alexander.
Most of the light they saw came from this material, which was being blown into space at a rate of about 6,000 miles per second. Spectral studies showed that the material that flowed out of the black hole was identical to the material that fell into it – evidence that it was crumbs from the clumsy star.
The AT1910qiz torch could serve as a “Rosetta Stone” to understand other events that destroy stars, said Dr. Alexander. AT2019qiz was special, she added, because astronomers observed it very early, immediately after the star was torn apart, collecting so much data from many different types of telescopes.