Is this science's latest call for ducking and covering? Researchers working with a newly detailed model of black hole creation say our Milky Way galaxy alone may be host to hundreds of black holes sailing almost invisibly through space, sucking in the matter in their path.
But don't worry, they say. The chances of getting hit are slim.
Here's the background. Scientists are fairly confident about the existence of two kinds of black holes. There are relatively small ones, less than 100 times the mass of our Sun, that are created from the death of large stars. Then there are the "super-massive" ones at the hearts of galaxies, with the mass of millions to billions of stars.
A third, intermediate type is still controversial. This type, some researchers say, could be created inside ancient globular clusters of stars, weighing as much as a few thousand solar masses. Two possible observations of this kind of object have been made, although identification remains tentative.
Researchers at Vanderbilt, Penn State, and the University of Michigan have created a surprising model of what would happen if black holes of this type were to merge. If two objects of different sizes or spin merge, the conservation of momentum could kick the resulting, larger object away from its original location at speeds of up to nearly 2500
miles per second.
That's well above the escape velocity for the average globular cluster, which means these merged black holes could go merrily sailing into the neighborhood, the researchers say.
Dangerous for those nearby? Sure. Here's one alarming thought from the researchers' press release:
However, the researchers say we shouldn't spend any sleepless nights because of it.
Galaxy may hold hundreds of rogue black holes [Vanderbilt press release]
(Image: Globular star cluster G1, a group of about 300,000 orbiting the
Andromeda galaxy, as seen by the Hubble telescope. Source: NASA)
