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Tiny black holes may be exploding stars across the Milky Way
https://iopscience.iop.org/article/10.3847/1538-4357/ae6db7 https://iopscience.iop.org/article/10.3847/1538-4357/ae6db7
- empath75 2mo agoThis is one of those headlines where I simultaneously think "cool" and now have a new source of low-grade background anxiety about. It can have a seat next to false vacuum collapse.
- trollbridge 2mo agoThe good news about black holes is that even if one transited the solar system, it would be extremely unlikely to come anywhere near earth.
- ben_w 2mo agoThe bad news is that if a black hole is not primordial, the minimum mass is high enough (2-4 M_sol) that it doesn't so much "pass through our system" as "we pass through its". I'm not 100% confident, but rough approximation suggests that a close approach of even 5 AU even at typical interstellar velocities might have an unplesant climate impact by increasing the eccentricity of our orbit.
- mynegation 2mo agoDid you mean 5 AU or 5 ly? 5 AU at 2-4 M sol intuitively seems like a complete and utter havoc.
- ben_w 2mo agoWe know what something with about 2 solar masses looks like at about 5 light years, because there is such a thing a bit closer: the Alpha Centauri system. So (and again, this is very rough approximation) I mean AU: consider the high speed of interstellar encounters so it won't be there for long, and that it takes the full pull of Sol 6 months to turn us around 180°. Also, yes, in general this would cause a lot of the Oort cloud to destabilise and a long period of bombardment of all the planets.
- kbelder 2mo agoAt 5 AU, gravitational force would be 1/25 or 4% the strength of the sun at 1 AU. If the black hole was four solar masses, it would exert a pull about 16% as strong as the sun. Probably not enough to rip us out of orbit, but enough to seriously perturb it. I think it's at least an end-of-civilization event. 5 AU is the perfect distance to really wreck Jupiter, though.
- bell-cot 2mo agoNot an astrophysicist, but I'm thinking 5 AU could quickly fry the Earth - because it takes very little in the way of solar comets, asteroids, and dust to build a temporary accretion disk around such a black hole. That disk might have a temperature of >1M degrees. Plus the dynamo effects of the disk's interactions with the solar magnetic field? Yeah. 5 ly sounds much safer.
- ben_w 2mo ago> Yeah. 5 ly sounds much safer. Well yeah. I clearly could've phrased this better though: I was aiming for "here is an example distance which *is* bad", not as it appears to have been understood "here is the distance where it is *not* bad".
- kbelder 2mo agoYeah, I'm sure you're right. I was looking purely at orbital mechanics and gravity, but I think a four-stellar-mass black hole would certainly have other harmful environmental effects that would be felt at that range.
- trollbridge 2mo agoDéstabilise orbits - definitely, but the same would be true of a star or other celestial body. But our risk of getting sucked into a black hole is really tiny. (Although personally if I had a chance to enter a black hope, I would. I’m just naturally curious.)
- 14u2c 2mo ago5AU seems incredibly close. That's inside the orbit of jupiter. How would it not destabilize the entire system?
- 98codes 2mo ago> extremely unlikely But never zero.
- Zigurd 2mo agoTake comfort in the fact that compared to the size of the universe, the speed of light is like molasses in January. Cosmological eschatology is a very slow game, and the odds of you being alive and in the right place to be a spectator are literally astronomically small.
- OneDeuxTriSeiGo 2mo agoIn that case you may enjoy “The Blue Afternoon that Lasted Forever” by Daniel Wilson. https://web.archive.org/web/20260310115201/https://www.williamflew.com/blue.html https://web.archive.org/web/20260310115201/https://www.willi...
- alansaber 2mo agoConcern for celestial events is a bit like one of your gut bacterium being concerned with your work schedule
- vkazanov 2mo agoThese little guys often do get a hammering on fridays...
- thisisauserid 2mo agoThe "Great Filter" answer to the Fermi Paradox.
- stronglikedan 2mo agoIt seems like it would be the most efficient implementation of the Great Filter, since it would just look like a natural occurrence to any observers.
- cousinbryce 2mo agoAnyone have guesses about how a transiting primordial black hole would effect a Sun like star? Paper is about tidal forces inducing supernova in white dwarfs. For that matter how might it effect sea tides?
- pavel_lishin 2mo agoFor the latter, you mught enjoy Greg Egan's "Perihelion Summer".
- ButlerianJihad 2mo ago[flagged]
- deleted 2mo ago[deleted]
- Quinner 2mo agoPerhaps you meant to read the https://news.ycombinator.com/newsguidelines.html https://news.ycombinator.com/newsguidelines.html about comments being kind, not snarky, and substantive.
- antognini 2mo agoWe have constraints that primordial black holes must be less than the size of a large asteroid. They would be gravitationally insignificant to the Earth unless they actually passed through it. I also don't think it would really be detectable in the Sun. Perhaps there would be some transient astroseismology signature.
- jandrewrogers 2mo agoMost likely minimal? The mass is low. I am, however, reminded that the orbit of the asteroid Juno (~250km diameter) permanently changed in 1839 without an obvious cause.
- shagie 2mo agoHow to spot tiny black holes that might pass through the solar system - https://www.sciencenews.org/article/primordial-black-holes-solar-system https://www.sciencenews.org/article/primordial-black-holes-s... And the referenced papers: Probing primordial black holes and dark matter clumps in the Solar System with gravimeter and Global Navigation Satellite Systems networks - https://journals.aps.org/prd/abstract/10.1103/PhysRevD.110.063029 https://journals.aps.org/prd/abstract/10.1103/PhysRevD.110.0... Close encounters of the primordial kind: A new observable for primordial black holes as dark matter - https://journals.aps.org/prd/abstract/10.1103/PhysRevD.110.063533 https://journals.aps.org/prd/abstract/10.1103/PhysRevD.110.0... And the PBS Spacetime: How Many Black Holes Are In The Solar System? - https://youtu.be/wh75ubECL8I https://youtu.be/wh75ubECL8I
- boesboes 2mo agoWouldn't Type Ia supernovas caused by blackholes have a different brightness? That could mean the entire cosmic ladder needs to be revised, maybe this could resolve the crisis in cosmology..
- sgt101 2mo agoCould this kind of trigger effect the standard candle application of Type 1a's? For example, if a black hole triggers a type 1a and that perturbs the type 1a light curve in some way (possibly because less mass could be consumed in the explosion than you would get if one was triggered by mass accretion) and the rate of triggering of this kind changed over time as the universe aged and somehow the population of primordial black holes changed, or the distributions of white dwarf candidates and pbhs changed...
- antognini 2mo agoThey did some modeling in a previous paper of how this would impact Ia supernovae and it depends on whether the supernova is driven by Kelvin-Helmholtz instabilities or not. In the case that it is, this would only trigger Ia supernovae for white dwarfs which are already very close to the Chandrasekhar mass. In this case the standard candles would be pretty much the same. In the case that KH instabilities are weaker they claim that you can get supernovae at masses farther from the Chandrasekhar limit. This could plausibly have more of an impact on Ias as standard candles. (Though perhaps less than you might think becauseit would also likely have an effect on the shape of the light curve, and Ias are normalized based on their light curve shape.) All that said, even if this process does occur, I doubt the rates would be high enough for it to be a substantial fraction of observed Ias.
- Schlagbohrer 2mo ago3-Body-Problem once again vindicated as the scariest possible explanation for the Fermi Paradox
- criddell 2mo agoDid you intend to say dark forest hypothesis?
- Schlagbohrer 2mo agoYes!
- istjohn 2mo agoAccording to physicist Sean Carroll, "hypothesis" and "theory" are interchangeable as the words are used by practicing scientists.
- rigrassm 2mo agoI love Sean Carroll (Something Deeply Hidden and From Eternity to Here are the root of my fascination with physics and endless pondering of the nature of time) but I have to disagree with his take on this. Hypothesis - a proposed explanation for something (such as a phenomenon of unknown cause) that is tentatively assumed in order to test whether it agrees with facts that are known or can be determined. Theory - a scientifically acceptable or plausible general principle or body of principles based on data and offered to explain phenomena Just because those outside of scientific fields use them interchangeably doesn't change the fact that they carry different meanings in scientific contexts.
- criddell 2mo agoIsn't Planck's hypothesis really a theory? Isn't string theory really a hypothesis?
- marcosdumay 2mo agoIt seems to relate much more to the size of the proposal than to its confidence. Even more because the confidence changes all the time, but people do go around renaming well known ideas
- raiyanr 2mo agowhen will sun be exploaded?
- Y-bar 2mo agoMore than eight minutes ago. At least.
- aklemm 2mo agoAnd yet no one does a thing about it.
- CookieCrisp 2mo agoWhat would you like done?
- PowerElectronix 2mo agoBe the change you want to see in the world. Go out there and start swatting away nanoscopic black holes.
- choboswaggings 2mo agoKind of chilling to think about these tiny black holes. If they have enough gravitational pull to destabilize a white dwarf, I don't want to know what they'd do to our solar system.
- ttul 2mo agoThese supernova-generating black holes are atomic scale (Schwartzchild radius of 15pm to 15nm), yet they carry the momentum of a large asteroid. If one of these hit the earth, they would cause a life-ending apocalypse like the event that ended the dinosaurs. The fact that this has not happened yet is encouraging.
- YetAnotherNick 2mo agoThe drag is insufficient to stop it and it would go right through the earth without stopping. It would cause earthquake of 4 magnitude, which is barely detectable. [1]: https://arxiv.org/pdf/1203.3806 https://arxiv.org/pdf/1203.3806
- shagie 2mo agoCan one detect passage of small black hole through the Earth? - https://arxiv.org/abs/0710.3438v1 https://arxiv.org/abs/0710.3438v1 A physics stack exchange answer about it: https://physics.stackexchange.com/a/55184 https://physics.stackexchange.com/a/55184 The most relevant part: > The total energy created by a PBH roughly equals the energy produced by the detonation of one tonne of TNT, but this energy is the total energy it deposits along its path through the Earths diameter, not the energy it produces on impact. So don’t expect a magnificent explosion, we’d be lucky to see a spark as it hits the ground.
- BedVibe_Studios 2mo ago[flagged]
- brabel 2mo ago[flagged]
- ck2 2mo agoIf I remember correctly, Stephen Hawking had to do some serious math in the 1970s to convince himself a tiny black hole was not hiding in our Sun I think there's a PBS Space Time on it (of course) adding: yup! love that show * https://www.youtube.com/watch?v=Q6kJaMf3Lgo https://www.youtube.com/watch?v=Q6kJaMf3Lgo
- mmmBacon 2mo agoSounds like PMH, if they exist, are essentially the Universe’s ultimate cannonball.
- gigatexal 2mo agoNo no no ... they're Monoliths from 2001: A Space Odessy, remember when he became one and would go from star to star blowing them up for fun?
- iandanforth 2mo agoI didn't understand how a black hole could pass through a star when I read this. I think of black holes as large. Apparently a primordial black hole can have the mass of an asteroid compressed into a space smaller than a proton. I also thought very small black holes evaporated quickly via Hawking radiation. I was wrong on the scale there too. A PBH with the mass of an asteroid can easily live for longer than the universe has been around. Something about the very very early universe let matter collapse into these things without the normal processes that form stellar sized black holes.
- idiotsecant 2mo agoThe very early universe was quite dense, compared to today. Getting enough stuff in the same place to form an event horizon was relatively easier.