Milky Way's Black Hole Spews Out Enormous 'Spitballs' The Size of Planets

It's difficult to imagine planet-sized spitballs hurtling through space, but new research shows black holes cause exactly this phenomenon.

According to a news release from Harvard-Smithsonian Center for Astrophysics, there's a black hole smack dab in the center of the Milky Way. Every thousand of years, a star drifts close and finds itself ripped apart by the powerful gravity of the black hole. This process is known as a tidal disruption. Then, the study observed, the shredded debris and gas products can form into planet-sized objects that are whipped back out into space - just like a spitball.

"A single shredded star can form hundreds of these planet-mass objects," said Edna Girma, lead author of the study as well as undergraduate student at Harvard University and a member of the Banneker/Aztlan Institute. "We wondered: Where do they end up? How close do they come to us? We developed a computer code to answer those questions."

The size of these so-called spitballs? Massive. Girma's estimates have them weighing somewhere between Neptune and several Jupiters. The Milky Way black hole must have produced a number of these masses, but the researchers calculate the closest to Earth are likely a few hundred light-years away. Most - roughly 95 percent - would probably find their way out of the galaxy due to the speed of their movement which measure to about 20 million miles per hour.

While these objects are the size of planets, they're very different from the heavenly bodies actually classified as planets. The compositions are likely different because of their origin: stars. These mysterious orbs also form a lot more quickly; while planets take millions of years to come together, a black hole need only a day to shred a star and another year for the debris to merge into a "spitball".

Finding one is a challenge to scientists. In a report from Astronomy, Girma pointed out, "By the time they reach us, they'll be extremely cold."