Is ‘Planet Nine’ actually a grapefruit-sized black hole?

Posted: July 12, 2020 by oldbrew in Astronomy, methodology, research
Tags: ,

Credit: NASA

Could there even be more than one black hole? The search for a significant extra planet has drawn a blank so far.
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A coming sky survey will help test a wild idea — that a grapefruit-sized black hole lurks undiscovered in the outer solar system, says Mike Wall @

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 5 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.

The highly anticipated Vera C. Rubin Observatory, a big telescope under construction in the Chilean Andes, is scheduled to begin a wide-ranging, decade-long survey of the southern sky called the Legacy Survey of Space and Time (LSST) in late 2022.

Continued here.

  1. JB says:

    Research money always goes to those people who have the least ability to think clearly.

    The entire basis of the black hole concept (Einstein’s) rests on a theoretical universe consisting of only one mass, and a gravitational field existing outside the body (despite the fact that gravitational fields can only exist where there is more than one mass). Additionally, “spacetime”, a concatenation of two concepts that have no physical expression, which do not have any underlying physical relation to each other, cannot be treated by geometric principles, which rely on dimension, which neither concept of “Space” nor “Time” possess.

  2. Kelvin Vaughan says:

    It might be a grapefruit sized black hole at the moment but just wait. 😂.

  3. Curious George says:

    The concept smacks of desperation.

  4. oldbrew says:

    Comet captured streaking across Stonehenge night sky

    Comet Neowise has been spotted by stargazers across the UK and around the world as it heads past Earth.

  5. #NoBlackHoles 😎

  6. Peter Norman says:

    I thought a black hole was zero size and infinite density. Dr Avi Loeb thinks there are 50 quadrillion (10**15) black holes in the Milky Way. How unlucky is Sol – to end up with a grapefruit version!

  7. oldbrew says:

    Black Hole Firewalls Confound Theoretical Physicists

    If a new hypothesis about black hole firewalls proves correct, at least one of three cherished notions in theoretical physics must be wrong.

    By Jennifer Ouellette, Quanta Magazine on December 21, 2012

    Paradoxes in physics have a way of clarifying key issues. At the heart of this particular puzzle lies a conflict between three fundamental postulates beloved by many physicists.
    . . .
    If there is an error in the firewall argument, the mistake is not obvious. That’s the hallmark of a good scientific paradox. And it comes at a time when theorists are hungry for a new challenge: The Large Hadron Collider has failed to turn up any data hinting at exotic physics beyond the Standard Model. “In the absence of data, theorists thrive on paradox,” Polchinski quipped.

  8. Gamecock says:

    A black hole would have to have significantly more mass than Sol. I don’t think there is anything that big close to us. We’d notice its effects.

  9. tallbloke says:

  10. oldmanK says:

    Quote Gamecock “A black hole would have to have significantly more mass than Sol.” According to Wiki there are Micro black Holes; see

    It seems banks have begun to acquire MBH.

  11. oldbrew says:

    Wiki’s micro black holes are hypothetical.

    Micro black holes, also called quantum mechanical black holes or mini black holes, are hypothetical tiny black holes

  12. According to Steven Hawking the original definition of a black hole was something like “A black hole is a region of spacetime where gravity is so strong that nothing—no particles or even electromagnetic radiation such as light—can escape from it. The theory of general relativity predicts that a sufficiently compact mass can deform spacetime to form a black hole.”
    However, it has been found that areas thought to be black holes can radiate radio waves, radiate microwaves and even bursts of plasma, It is clear that these can not be black holes as defined. A new name is required. Further, Hawking later changed his mind and there is great uncertainty about space time curvature. I tend to think that there is a swing to a infinite universe where our sight and the so-called big bang is just a tiny area of the infinite universe which is not expanding (by definition)
    How about calling these “black holes” as a space volume with an high internal gravity force which may have at its core solid matter.
    Note I had the book “A brief History of Time” 1988 which I read and eventually threw out as his theory did not stand up and some of his maths is based on contradictory assumptions.

  13. Jim says:

    Interesting. And the evidence is a trail of debris. A accumulation of mass in a empty field. And there are stars that have come close enough to have been a second sun. And have left our area. That could have left the same trail. Interesting. A black hole redefined as a glowing object?

  14. tom0mason says:

    More white privilege!
    Black Hole Matter!