Is Our Solar System's Ninth Planet Actually a Primordial Black Hole? (forbes.com) 165
An anonymous reader quotes Forbes:
Conventional theory has it that Planet 9 — our outer solar system's hypothetical 9th planet — is merely a heretofore undetected planet, likely captured by our solar system at some point over its 4.6 billion year history. But Harvard University astronomers now raise the possibility that orbital evidence for Planet 9 could possibly be the result of a missing link in the decades-long puzzle of dark matter. That is, a hypothetical primordial black hole with a horizon size no larger than a grapefruit, and with a mass 5 to 10 times that of Earth.
In a paper accepted for publication in The Astrophysical Journal Letters, the co-authors argue that observed clustering of extreme trans-Neptunian objects suggest some sort of massive super-earth type body lying on the outer fringes of our solar system. Perhaps as much as 800 astronomical units (Earth-Sun distances) out...
If they exist, such primordial black holes would require new physics and go a long way towards solving the mystery of the universe's missing mass, or dark matter.
Their argument also constitutes a "new method to search for black holes in the outer solar system based on flares that result from the disruption of intercepted comets," according to a statement from the Harvard-Smithsonian Center for Astrophysics. The paper was co-authored by Avi Loeb, chair of Harvard's astronomy department, who points out that "Because black holes are intrinsically dark, the radiation that matter emits on its way to the mouth of the black hole is our only way to illuminate this dark environment."
And in an explanatory video, Mike Brown, a planetary astronomy professor at CalTech, suggests another way it could be significant. "All those people who are mad that Pluto is no longer a planet can be thrilled to know that there is a real planet out there still to be found."
In a paper accepted for publication in The Astrophysical Journal Letters, the co-authors argue that observed clustering of extreme trans-Neptunian objects suggest some sort of massive super-earth type body lying on the outer fringes of our solar system. Perhaps as much as 800 astronomical units (Earth-Sun distances) out...
If they exist, such primordial black holes would require new physics and go a long way towards solving the mystery of the universe's missing mass, or dark matter.
Their argument also constitutes a "new method to search for black holes in the outer solar system based on flares that result from the disruption of intercepted comets," according to a statement from the Harvard-Smithsonian Center for Astrophysics. The paper was co-authored by Avi Loeb, chair of Harvard's astronomy department, who points out that "Because black holes are intrinsically dark, the radiation that matter emits on its way to the mouth of the black hole is our only way to illuminate this dark environment."
And in an explanatory video, Mike Brown, a planetary astronomy professor at CalTech, suggests another way it could be significant. "All those people who are mad that Pluto is no longer a planet can be thrilled to know that there is a real planet out there still to be found."
Dwarf planet (Score:3, Interesting)
There wouldn't be any ninth planet, as such a body would be a dwarf planet!
Look, son, a planet is a solar system body that needs to have cleared its neighbourhood. That be virtually impossible at the proposed orbits even for a gas giant-sized body.
Look, you don't go all the way in introducing a half-cooked* definition just to disqualify Pluto as a planet as it didn't look like one to you just because you thought excluding it explicitly would feel arbitrary, and then immediately ignore your own definition when a thing that looks a planet to you becomes possible to exist.
* The definition doesn't even account for extra-solar planets, as it requires planets to orbit the Sun.
Re: Dwarf planet (Score:2, Informative)
Re:Dwarf planet (Score:5, Interesting)
Unfortunately for Pluto, its characteristics match more closely with these trans-Neptunian objects than it does the classic planets. So it was demoted.
Re: (Score:2)
Then the definition needed to be "Objects with the following physical characteristics: [list goes here] or for which a historical precedent exists to call them planets."
It's as simple as that. No danger of textbooks needing to be overwritten. No need to demote Pluto.
Possibility to Explore a BH (Score:3)
There wouldn't be any ninth planet, as such a body would be a dwarf planet!
If it is a Black Hole then it is not a planet at all since will have formed by a completely different mechanism and will have radically different properties. Indeed, I really hope it is a Black Hole since, with it being in the Solar System, it will be near enough to send a probe to. This will allow us to confirm things like Hawking Radiation but perhaps also so start refining models of Quantum Gravity far, far sooner than anyone has ever though possible.
Magic physics solves problem? No. (Score:4, Interesting)
This was interesting until they noted the size which current physics says is too small to be a black hole. Then they doubled down and said "well yeah we know but wouldn't it be super cool if there were some totally new physical laws of magical gravity and mass we could make up so we can get more funding next year?"
Re: (Score:2, Informative)
Yeah, it's almost as if scientific endeavour starts out with speculative theories and then looks for funding to try and prove or disprove them to advance humanity or something.
You're not even Way Smarter Than a Broken Dildo, let alone any actual human.
Re: (Score:3)
Re:Magic physics solves problem? No. (Score:5, Interesting)
There is nothing about an earth mass black hole, or thereabouts, that violates physics or requires new physics.
The thing is, other than "maybe many of them were formed during the big bang and survived billions of years without getting noticed before", there is no mechanism how one of them could be created.
We know how neutron stars and black holes can be formed from large stars. There is no plausible mechanism for compressing a few earths worth of matter into the volume of a grapefruit. And wouldn't even a small black hole collect some interstellar gas into a mini-accretion disc that would render it visible?
Re: (Score:3)
No more than Neptune has collected a detectable accretion disk.
Re: (Score:3)
Well, Neptune doesn't have a surface gravity acceleration of 10^15 m/s^2 either. I don't know how close a particle needs to get to the Schwartzschild radius in order not to escape anymore, due to the non-conservative gravitational potential under relativistic conditions and due to radiation losses, nor how much radiation they would emit before they are swallowed. But I'd estimate that there can easily be 10^9 molecules per second per square meter (10^6 per m^3 density, 1 km/s velocity); it's not obvious to
Re: (Score:2)
Re: (Score:2)
Particles falling into the black hole don't radiate. Accretion disk radiation is X-rays from friction between particles in the disk. That depends a great deal on the size, speed and density of the disk. There isn't much stuff out that far, and a few Earth masses isn't that much gravity to capture and hold onto what stuff there is.
The paper's authors do suggest searching for a low mass primordial black hole using x-ray emission, but x-rays from a dark matter halo that they expect would gather around primord
Re: (Score:3)
Re: (Score:2)
I don't think I really followed what you're trying to say. The idea in the paper is that primordial black holes, which form in a very dense (matter and dark matter) universe, would hold onto their own little halo of dark matter. Not *in* the hole, around it. That over density of dark matter might be detectable because it would produce a very specific frequency of x-ray when it annihilated. If it annihilates.
That is certainly lots of assumptions and is unlikely to work.
Re: (Score:2)
Re: (Score:3)
It doesn't matter if they're completely invisible or not.
We're barely at the stage of indirectly observing large planets around other stars. It's very likely that the methodology we use to detect planets around other stars would exclude attempts at observing a similar mass black hole.
A lot of the planet detection relies on watching the brightness of nearby stars dip like 1% on a regular basis as the planet occludes the star. Even if a primordial black hole had a ring, it likely wouldn't trigger the algorith
Re: (Score:2)
Re: (Score:2)
Even hubble is going to struggle to find a hypothetical grapfruit with a ring that far out.
Yeah, we're not going to find it visually. We'll have to find it by it's gravitational effects, I think. I'm not even sure if you could send a probe to look for it in the neighborhood it's supposed to be in and be able to 'see' anything, not if it's as small as they're saying it could be. It's not going to have a bunch of junk orbiting it, not if it's that small. Detect tidal effects from it, maybe?
Re: Magic physics solves problem? No. (Score:3)
Re: (Score:2)
wrong, there are plausible mechanisms in the early universe and Hawking wrote paper on it.
Re: (Score:2)
Re: (Score:2)
Re:Magic physics solves problem? No. (Score:4, Interesting)
What? There's no minimum size for a black hole. The only issue with small ones is explaining how they formed. Primordial black holes have been a popular explanation for the existence of small black holes for quite a while, because they probably should have formed in the early universe. The only "new physics" required would be to explain how they could make up a substantial portion of dark matter.
Re: (Score:2)
The only "new physics" required would be to explain how they could make up a substantial portion of dark matter.
I suppose the thinking would be "there were many many of them formed at the same time"? And, if they're stable, they survived all these billions of years? And, if there's a 'grapefruit sized' one hanging around our local neighborhood, it got that way by clearing out random junk, increasing it's mass and size?
Re: (Score:2)
There are a bunch of observations that put limits on the number of black holes in specific size ranges. They don't seem to collide with neutron stars, white dwarfs or regular stars, microlensing searches, etc. I think there's still a bit of room for a significant fraction of dark matter to be primordial black holes, but it doesn't look very likely under our current understanding of the early universe.
Re: (Score:2)
Re: (Score:2)
Re: (Score:2)
The only likely missing out there would be the left overs from the impact of Venus to give it it's contra orbit, distinct surface formations and screwed up atmosphere. It would be interesting to calculate the original orbits for Venus based upon that impact sufficient to alter it rotation and what the model of the solar system was like prior to that. Also why Mars has two distinct surfaces, like one was added long after it was formed.
The only thing out there would be impact debris there nature dependent up
Re: (Score:2)
"Magical roperties of physics" has been the foundation of the "dark matter" theories, which do not pan out.
Re: (Score:2)
"Magical roperties of physics" has been the foundation of the "dark matter" theories, which do not pan out.
More than that, it's literally the foundation of all physics. We know the laws of physics are incomplete, as an absolute fact. The funny thing is, every single law of physics wasn't in our definition of it at some point in the past. And the even funnier thing is, literally every aspect of physics was some literally-interpreted-as magical property until being defined as physics.
Re: (Score:2)
Physics properties go through scientific testing. They are deliberately and clearly explained so that others can reproduce the results.
"Magical properties" are either deliberately left obscure to all with no explanation, or revealed only to the enlightened priesthood. They lack predictive power and verifiability. It's one of the issues with many dark matter theories. The authors are charmed by the complexity without data.
Re: (Score:2)
Re: (Score:2)
What? Explaining a term, especially if it's logically misused, is vital to making a point. That is is why I just responded to _your_ point.
Re: (Score:2)
Re: (Score:2)
Re: (Score:3)
Sure but do you really think we will discover some magical new property of mass that allows for tiny black holes? All sorts of new objects? Yes. The universe is big. Very big. But a new property of matter? Uh....
You are why science has stopped producing things. Please find a new hobby.
Re: (Score:2)
Very big. But a new property of matter?
But it IS a new property of matter. They've already found it and want to use it before it evaporates like small black holes are apt to do.
They've discovered a Green hole. In other words, it's the well known property of throwing good money after bad. And I'm sure the "Law of Attraction" (nothing at all to do with gravity) is somehow mixed in there for good measure, too.
Re: (Score:2)
Re: (Score:2)
Re: Magic physics solves problem? No. (Score:2)
Wow, yeah your logic and reasoning and facts and citations sure put me in my place! There is no way to refute the strength of your argument. You are deep and profound! (Are you smart enough to detect sarcasm?)
Please explain why such a small mass can produce a magical physics mini black hole yet Jupiter and Saturn are way more massive yet didn't collapse into a similar object.
In science (real science, not your sci-fi ad hominem style wishing magical science), the status quo is what we all agree to until s
Re: (Score:2)
Please explain why such a small mass can produce a magical physics mini black hole yet Jupiter and Saturn are way more massive yet didn't collapse into a similar object.
Why should I? Did you not RTFA? It's in there, or are you too scientifically-illiterate to understand what was written and instead opted to spout off on the internet playing the "safe" side of "nothing is ever discovered or created" until your pop-sci entertainers tell you otherwise? Nevermind...I already know.
Re: Magic physics solves problem? No. (Score:2)
I read the article. Did you? It is full of magic and witchcraft wishery physics.
Did you read the memo? Desire and faith are the realms of religion and sorcery. Not science.
Please note for me where the real science is in this article that provides any reason to believe a micro black hole is wandering around the outer edges of the solar system and how its existence is even possible without a bat wing, faith, and a cauldron to stir them.
Your ad hominem is boring and typical and expected from the ignorant.
Re: (Score:2)
it's too small to be a black hole by any theorems that fit observed phenomena and furthermore why would it stay small? they know it's probably not right too, it's just throwing stuff at the wall.
by the extreme other logic spirit science might be true. which it isn't, the moon isn't hollow. the paper says it could be a black hole but also that it couldn't. I don't get it why they say black hole? why don't they say that some unknown object with mass xyz, which might be new unknown material that normally shou
Re: (Score:3)
You seem not to grasp what a black hole is.
It can basically be nearly infinitesimal light and small (yes - exaggerating a bit)
So no "new physics" needed to explain a grapefruit sized black hole with 3 - 4 times earth mass.
Re: Magic physics solves problem? No. (Score:2)
I understand as well as anyone who doesn't study them everyday what a black hole is.
If a handful of earth masses was enough to form a black hole then they'd be fucking everywhere and we'd have a black hole instead of Jupiter.
Apply common sense. Their theory of tiny black holes makes no sense. Why is Jupiter there and not falling into itself to create a mini black hole much bigger than this magical physics object they are wishing into existence to plug holes in other theories?
Re: (Score:3)
If a handful of earth masses was enough to form a black hole then they'd be fucking everywhere and we'd have a black hole instead of Jupiter.
Apply common sense. Their theory of tiny black holes makes no sense. Why is Jupiter there and not falling into itself to create a mini black hole much bigger than this magical physics object they are wishing into existence to plug holes in other theories?
as i understand it (no astrophysicist either), because it is about density, not absolute matter. the circumstances for such high density to occur in just a handful of earth masses would be very particular and thus rare.
jupiter will eventually fall into a black hole. everything will.
No, it isn't. (Score:2)
Re:No, it isn't. (Score:5, Insightful)
Re: (Score:2)
How about we just launch a probe and aim it at where this supposed tiny black hole is going to be? It'll take what, 25-30 years to get out there, but at least we'll see if the probe suddenly gets gobbled up by something invisible.
Two possibilities (Score:5, Funny)
1) Space is large and it's really really hard to find something orbiting 100 billion km out.
2) It's a micro black hole hitherto-fore unexplained by physics.
Yep we're going with number 2 because Occam's Razor isn't a thing.
Re:Two possibilities (Score:5, Insightful)
We're going with number 2 because it's easier to test. Then we'll go back to number 1. Science.
Re: (Score:2)
3) There is no planet nine, just the combined gravitational influence of a lot of smaller stuff [sciencealert.com].
Re: (Score:2)
How in HELL is this flamebait?
If it's a primordial black hole (Score:3)
It establishes that they exist and that they're common enough to be found in our solar system. How common are they? If they're common enough for a large percentage of stars to have collected them, and they're also distributed remotely evenly in intergalactic space, then they're a comprehensible source of so-called "dark matter" with no new physics involved. Note also that primordial black holes do _not_ involve new principles of physics, simply a previously described of the Big Bang that is very difficult to detect. The theory is more than 50 years old.
Re: (Score:2)
Re: (Score:2)
Do you have any pointers to the models for "the size of Earth and a grapefruit"? I assume you mean a black hole the mass of the Earth.
The likelihood of collisions is a fascinating problem, and very dependent on their density. Since they're so difficult to detect directly, their density is also a fascinating question.
Re: (Score:2)
Re: (Score:2)
Re:If it's a primordial black hole (Score:5, Interesting)
...then they're a comprehensible source of so-called "dark matter" with no new physics involved...
Not really. The paper (which is here [arxiv.org], /. never gives usable links to papers) is only claiming that they might account for up 10% of the dark matter mass of the Milky Way Galactic Halo.
There is at this point only a narrow (logarithmic) range of black hole masses that could be invoked to explain the 85% of the matter in the Universe that we cannot detect, but by its large scale gravitational effect. This range is from 10^13 to 10^16 tonnes at most. Any process in the early Universe that converted 85% of its mass into black holes in the narrow very small size range would absolutely be entirely new physics. Dark matter is real, we can measure its distribution in the Universe, and even in our galaxy, and it isn't made of anything that we currently know exists.
Headline is politically incorrect! (Score:2)
Re: (Score:2)
I know you're being funny/sarcastic, but at the end of the day I don't think we can erase the entire concept of color from our language with regards to describing objects visual appearance, not without breaking our langua
Re: (Score:2)
Re: (Score:2)
Nemesis (Score:2)
Re: (Score:2)
A Black Hole not far from Uranus? (Score:2)
If these were common, we would have detected them (Score:2)
Re: (Score:2)
No, not if orbit large, won't detect wobble.
Re: (Score:3)
also should have added, with say earth mass or more and 800 au distance orbital period would be 23,000 year.... not going to see transits very often, heh.
Many masses (Score:2)
Highly elliptical orbits come close to the sun, so the mass can be tidally disrupted and one object can become many. (e.g. https://www.nature.com/article... [nature.com]) They can also be accelerated with each pass, (for instance this month's C/2020 F3 (NEOWISE) is leaving faster than it arrived) so that they are eventually ejected. The total mass in the orbit and the effects of that total mass could have still left the footprint we see on other solar system orbits.
So there are two well known explanations for why p
Planet X (Score:2)
Planet X theories have been around since 1906, [or Planet O in 1908 because O comes after (N)eptune] , to explain irregularities in the orbit of Uranus. However, once a more accurate mass for Neptune was obtained in 1993 the evidence for the existence of Planet X disappeared. Since Pluto was bumped to a snowball it's now Planet 9 that is heavy enough only to cause irregularities in outer solar system bodies, which we haven't proven the existence of.
They are talking about hypothetical forms of a hypothetica
Re: New physics... or metaphysics (Score:5, Interesting)
As is, what happens around a black hole event horizon is still unclear, but we pretty much know PBH exist from the LIGO detector and there are more PBH than expected. That might mean they don't evaporate exactly as Hawking radiation(which is also "new physics") would predict.
Re: (Score:2)
Re: New physics... or metaphysics (Score:5, Funny)
the co-authors argue that observed clustering of extreme trans-Neptunian objects suggest some sort of massive super-earth type body
It's OK, nothing to worry about, it's just the mother-in-law. She likes her fried food a bit too much, sigh.
Re: (Score:2)
Albeit a great deal messier [youtu.be]
Re: (Score:2)
Re: (Score:2, Interesting)
Whatever conceptual scope you have, you can never, it is formally demonstrated by Godel, know if there is a wider scope affecting the conclusions of your current scope. Even at the level of simple math.
This is why "scientific knowns" are continuously changing, as a simple empirically obvious fact.
And no, you won't know you're right next time either.
Re:New physics... or metaphysics (Score:5, Interesting)
You misunderstand Goedel's result. It has nothing directly to do with scientific theories. What Goedel showed was that mathematical truth cannot be formalized in a mathematical system that had certain capabilities regarding arithmetic. That's it. Mathematics is not actually a science, it's its own thing. A science, usually most of which is written in the language of mathematics, is a relationship between a theory and the physical world. I suppose one can go all wildly Platonistic and claim that mathematical "objects" are real, but this is philosophy, not science. For a brief introduction, look at the philosophies around what are the natural numbers.
Inflating Goedel's formal result in mathematics into somehow scientific theories are incomplete is a long stretch. In the first place, a physical theory is merely written in mathematics, its truths are mathematical, but its interpretation is not. Saying a physical theory is incomplete means that it does not cover all the phenomena in its purview. A mathematical theory of arithmetic does not have mathematical truth as its purview (something Hilbert and many (most?) others (Frege)) had thought. Rather it has arithmetical proof as its purview.
Goedel did some other work on general relativity. He came up with "rotating" universes which were solutions to Einstein's general relativity and wherein there can be closed time paths that wind back on themselves. His conclusion here was different, it wasn't that relativity is incomplete. Rather, his conclusion was that time in GR is but a mere simulacrum of time as we experience. What we experience is McTaggart's A system. McTaggart's B system is the one that formulates a time series for causality. To see the difference, there is no Now in the B system just as there is no now in GR. In fact, Einstein (among others) claimed there can be no Now in physics, probably because representing Now in mathematics is...difficult.
Re: (Score:2, Insightful)
Inflating Goedel's formal result in mathematics into somehow scientific theories are incomplete is a long stretch.
No. It is flat out wrong.
Goedel gets invoked a lot alongside quantum physics by people trying to cast an aura of impossibility around physics, without a real understanding of what either means.
Re: (Score:2)
Re: (Score:2)
A favourite runner up to Goedel is the halting theorem. You can prove that it is not possible to write a single program that can decide whether any possible program will halt or not. Therefore it is impossible to decide whether any program will halt.
We haven't proved the Halting Theorem. And that's not really what the halting problem would prove if we knew one way or the other if it is possible. What we would know is if Turning machines are decidable which has mathematical consequences for how you solve some problems in rare cases. Misunderstanding something and then mocking it, says a lot...about you.
Re: (Score:3)
Uh, riiiiight.
https://en.wikipedia.org/wiki/... [wikipedia.org]
Which doesn't solve the Halting Problem. It only gives an upper bound on what kinds of programs could have a halting problem solution. That bound being not all of them. But there are simple classes of programs which can be proved to halt. So somewhere in the middle is a line between programs which can be proved to halt and those which can't and we don't know where that line is currently. That's where the whole P/NP thing comes in. And knowing where that line lines helps us know if there are solutions
Re: (Score:3, Interesting)
Paradigm Shift happens to all sciences. This is because science reflects a model of reality. A description, it does not define reality.
So while the name used is is part of a math based philosophy, the idea is valid.
And you can complain that people try to make things mystical to discredit - but the reality is tha
Re:New physics... or metaphysics (Score:4, Funny)
Copypasta vs copypasta - now that's what I call a food fight.
Re: (Score:2)
This is why "scientific knowns" are continuously changing, as a simple empirically obvious fact.
it's still a lot more interesting, fun and thought provoking than religious drivel. douchebags and liars are everywhere but science per-se is at least a rational (and thus basically sincere) approach to the unknown, unlike religious drivel which simply dismisses any possibility of knowledge in favor of some arbitrary absolute philosophical truth that's just appealing to those who were overexposed to it (probably as kids or in vulnerable state in general) and have their rationalization capability severely at
Re: New physics... or metaphysics (Score:2)
Re: (Score:2)
It is about both, otherwise we had no single physical formula.
Re: (Score:2)
Considering that mathematics is the language that describes the Universe, you could also say that mathematics created us.
No, I'm NOT saying that 'mathematics is God'. Fuck no.
Re: (Score:2)
Wouldn't the Larry Niven explanation be that it's a lump of Neutronium?
Am sure there's some 'scientific' reason (pah!) why this couldn't be the case. But if it looks like a planet, swims like a planet, and quacks like a planet, then it probably is a planet.
Re: (Score:2)
Is it necessary to be such a fucking dick about this? I didn't SAY I have a fucking PhD in anything. Ease the fuck up already.
Re: (Score:3)
Frankly, the idea that something like that may be hanging around in the outer solar system, regardless of whether it's been out there for billions of years or not, scares the shit out of me.
Why? If a primordial black hole exists in the outer solar system, it's has just the same impact as any big celestial body out there.
Re: (Score:3)
Frankly, the idea that something like that may be hanging around in the outer solar system, regardless of whether it's been out there for billions of years or not, scares the shit out of me. Not something you want to fuck around with.
Speak for yourself, if we have a black hole that close to Earth it's a shitload easier to get to than the center of our galaxy, and a guaranteed route to time travel via the Kerr-Newman Metric [wikipedia.org]. The space race is going to get weird and possibly turn some billionaire into a timelord.
Re: (Score:2)
The space race is going to get weird and possibly turn some billionaire into a timelord.
Or a pancake.
Re: Read about this earlier this week (Score:2)
More like spaghetti
Re: (Score:2)
Yeah, I mean moving something as big a moon around the solar system is nothing, nothing compared to what humans are capable. Yes sir, give that possible black hole a wide berth lest it cast a baleful eye in our direction and then we'll all be lost.
Re: (Score:2)
Re: (Score:3)
For example are you afraid that the moon will fall on our heads? That Earth fall into the Sun? No? Because you understand orbital mechanics?
The same laws apply to a black hole as well. It could orbit another object, objects can orbit it. If objects falls onto it it will add them to is mass, just like a planet or our planet s
Re: (Score:2)
Well, she wasn't even a month old on Pluto!
Re: (Score:2)
You're in luck!
https://en.wikipedia.org/wiki/... [wikipedia.org]