The Black Hole in the Backyard?

Our solar backyard, maybe. A grapefruit-sized black hole may be hiding in our solar system

The hunt for the ever-elusive “Planet Nine” has taken scientists down some very strange roads. The idea that a planet exists in the outer reaches of our solar system and can’t be easily seen has been floating around for some time, and observations of other objects in the area suggest that there’s something big generating a gravitational pull. The easiest explanation would be a planet, but it’s not the only possibility.

Now, scientists from Harvard University in partnership with the Black Hole Initiative want to test the theory that the object that appears to be lurking on our system’s edge is actually a black hole. Yep, you read that correctly; there may be a black hole lurking right in our cosmic back yard.


The researchers plan on searching for this so-called “primordial” black hole using data from the Legacy Survey of Space Time, or LSST mission. The researchers say that they can use the data to search for evidence of accretion flares, which are created when objects get too close to a black hole.

“In the vicinity of a black hole, small bodies that approach it will melt as a result of heating from the background accretion of gas from the interstellar medium onto the black hole,” Amir Siraj of Harvard said in a statement.
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A “planet-mass” black hole could exist with a mass of between five and ten times that of our own planet. Being a black hole, the object would be much, much smaller than Earth, and the researchers suggest it could be as tiny as a grapefruit. Even at that size, it would have enough gravitational oomph to produce the kinds of movements in nearby objects that have been observed on the edges of our system.