Is 'Planet Nine' actually a grapefruit-sized black hole? Big new telescope could find out

[Judi Lynn]

By Mike Wall 20 hours ago

And it shouldn't take too long, either.



Artist's conception of accretion flares resulting from the encounter of an Oort-cloud comet and a hypothesized black hole in the outer solar system.
(Image: © M. Weiss)
A coming sky survey will help test a wild idea — that a grapefruit-sized black hole lurks undiscovered in the outer solar system.

Over the past few years, researchers have noticed an odd clustering in the orbits of multiple trans-Neptunian objects (TNOs), which dwell in the dark depths of the far outer solar system. Some scientists have hypothesized that the TNOs' paths have been sculpted by the gravitational pull of a big object way out there, something five to 10 times more massive than Earth (though others think the TNOs may just be tugging on each other).

This big "perturber," if it exists, may be a planet — the so-called "Planet Nine," or "Planet X" or "Planet Next" for those who will always regard Pluto as the ninth planet. But there's another possibility as well: The shepherding object may be a black hole, one that crams all that mass into a sphere the size of a grapefruit.

Astronomers are already scanning the heavens for any sign of Planet Nine, and they should soon be able to hunt for the putative black hole as well, a new study reports.

More:
https://www.space.com/planet-nine-black-hole-test-lsst.html

[Jeebo]

1. Robert L. Forward isn't with us any more.

He liked to write science fiction novels about the outer reaches of our solar system. Dragon's Egg and its sequel Starquake were impossible for me to put down. Camelot 30K comes to mind as well. This hypothesized black hole sounds like another one of his novels. Alas, if only he were still alive to write it.

-- Ron