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Milky Way’s Black Hole Just Flared, Growing 75 Times as Bright for a Few Hours
- hirundo 7y agoRemember when Beowulf Shaeffer took the Long Shot to the galactic core and discovered that it was exploding and would wipe out life in Known Space, so the Puppeteers moved their planets to parts unknown? Could this flare be a foreshock of that? It'd be nice to have some time to settle my affairs.
- Chris_Chambers 7y agoWe need more stuff like this that brings everyone together.
- human20190310 7y agoIt's awesome when a natural phenomenon matches a timescale that a human being can witness, rather than taking centuries or more. We get to see the whole show.
- zwkrt 7y agoThere is a neat physical argument that was made back when quasars and the like were just being discovered. Basically if the flash of brightness only lasts an hour, then you can argue convincingly that the source of the flash must be less than a light-hour across. The faster the flash, the smaller the bound on the size of the phenomena. This is what lead people to realize that quasars are wildly energetic but necessarily very small
- melling 7y agoI didn’t realize until recently that supermassives and classic black holes are formed differently. https://en.wikipedia.org/wiki/Supermassive_black_hole https://en.wikipedia.org/wiki/Supermassive_black_hole It’s also fun to remember that this event happened 26,000 years ago.
- kickopotomus 7y ago> It’s also fun to remember that this event happened 26,000 years ago. This is one of my favorite (but also the most daunting) things about space. It is so awesome (and bizarre) that we can essentially observe the past. In this case, the event occurred sometime around when humans were figuring out how to make baskets[1]. [1]: https://en.wikipedia.org/wiki/Timeline_of_human_prehistory https://en.wikipedia.org/wiki/Timeline_of_human_prehistory
- pacala 7y agoAlternatively, the present is the weighted average of past causal influences. This event had no causal influence over the humans figuring out how to make baskets. From Earth perspective, the event just happened.
- ggggtez 7y ago>weighted average No, the averages ignore input order. Reality is order dependent.
- DecoPerson 7y agoSo a photon emitted/reflected by some human weaving a basket may have just interacted with the Milky Way's supermassive black hole!
- 7y ago
- cosmotic 7y agoIf a black hole is of brightness 0 (by definition), then 75 times that is still 0. They are probably referring to something happening just outside the event horizon and thus something that is not actually the black hole and just a phenomenon caused by the black hole.
- Causality1 7y agoEven if there were no external matter in the vicinity of a black hole, its brightness would still not be zero thanks to Hawking radiation.
- jfengel 7y agoThere won't be any radiation from a supermassive black hole, or a stellar mass black hole. The bigger a black hole is, the colder it is, and any black hole bigger than a thimble is colder than the Cosmic Microwave Background. Its brightness isn't technically zero, but it's still darker than the background, and it's absorbing heat (and getting slightly bigger) rather than giving it off.
- Causality1 7y agoWhether or not it is absorbing radiation faster than it is emitting is not relevant to whether or not it is emitting at all. Black holes are pretty dang black but they are not "0 by definition".
- roywiggins 7y agoNobody's observed Hawking radiation, so we don't know for sure. Anyway, it's not obvious to me that the edge of a black hole is the event horizon. The event horizon is mostly empty space too. Maybe it's the ergosphere, which can be further out. Since a black hole is just a region of space, the boundary is sort of arbitrary.
- causality0 7y agoHawking radiation has been observed in multiple experiments. https://arxiv.org/abs/1009.4634 https://arxiv.org/abs/1009.4634 https://www.nature.com/articles/s41586-019-1241-0 https://www.nature.com/articles/s41586-019-1241-0
- deleted 7y ago[deleted]
- korijn 7y ago[Removed poor joke, no one thinks it's funny and it's attracting downvotes.. Please stop hurting my karma. I can't delete this post anymore either. Sorry.]
- IggleSniggle 7y agoFrom your replies, it sounds like it was funny! Sad for me that it’s now outside my reference frame
- korijn 7y agovardump quoted it in full in his reply here: https://news.ycombinator.com/item?id=20690603 https://news.ycombinator.com/item?id=20690603
- iamgopal 7y agoWhy multiply by 2 ?
- chimeracoder 7y agoOP is hypothesizing that an event happened on earth which emitted something traveling at the speed of light[0], traveled some distance, then interacted with some object which emitted something else[1] which traveled back to be observed on Earth. Hence, double the distance between Earth and the black hole, because it's traveling twice. I'm not sure exactly what OP is implying though. [0] light, radiation, information, etc. [1] ie, reflected, or caused some reaction
- deleted 7y ago[deleted]
- Izkata 7y ago> I'm not sure exactly what OP is implying though. The destruction of Atlantis?
- gillesjacobs 7y agoHere is the researcher's visualization of the near-infrared flaring activity: https://twitter.com/i/status/1160368687590727680 https://twitter.com/i/status/1160368687590727680
- codeddesign 7y agoIt seemed that the pulse jumped for about an hour. Obviously this happened thousands of years ago, but would that be a literal hour? How much time is lost/bent in transit?
- Sir_Cmpwn 7y agoOver the years of asking these kinds of questions myself, I've come to realize that this line of questioning betrays a fundamental lack of understanding of spacetime. Time is relative. From our perspective it might have happened a thousand years ago, but from alpha cen's perspective it happened at a slightly different time. There is no universal clock. Even the order in which events take place depends on your reference frame. So, it just happened, and the light took about 26,700 years to reach us, assuming nothing happened to it on the way (which is a bad assumption, even just because there's a lot of stuff between here and there, but especially considering it originated from a severely warped spacetime).
- delecti 7y agoWe're moving around it, but we aren't moving very fast (relative to c), and our relative distance from it isn't changing much. The duration shouldn't be much different despite the distance.
- dooglius 7y agoWouldn't time dialation around the black hole be very extreme? As in, from the perspective of just outside the black hole where the flare presumably started, it would have lasted only a very brief amount of time.
- deleted 7y ago[deleted]
- Retric 7y agoBright long lasting events like this are extremely unlikely to occur every close to the event horizon. https://en.m.wikipedia.org/wiki/Innermost_stable_circular_orbit https://en.m.wikipedia.org/wiki/Innermost_stable_circular_or...
- furdnacity 7y agoDoesn't look like I can comment on this article or contact the author, but there is a typo. > SO-2 made it’s closest approach about a year before the flaring observed in May 2019. Should be its not it's
- Udik 7y agoIt's a lost battle.
- quickthrower2 7y agoInnit a lost battle.
- MFLoon 7y agoCan any astronomers comment on if we are in any danger of getting blasted with gamma radiation or other black hole excretions?
- __jal 7y agoNo more so than you usually are. Which means it can happen to you at any time.
- lucb1e 7y agoSo you're saying that this event told us nothing whatsoever about the state and stability of these things? Sure it could always happen at any time, that's not a very useful thing to say. More interesting is what this event teaches us, if anything.
- _ph_ 7y agoDo you feel some burning sensation?
- NikkiA 7y agoAny such radiation would have arrived with the light of the black hole flaring. The fact that you're alive to read this implies that nothing fatal happened.
- luc4sdreyer 7y agoMaybe some people did die, it's a bit too early to tell if it killed, say ten people. It's probably very unlikely though. More importantly, there is a very wide spectrum of danger between death and no effect, especially when you consider things like cancer. I assumed that was the point of the grandparent's question.
- TearsInTheRain 7y agoSounds like we should all just stay inside to be safe from the blackholes. That suits me just fine
- quickthrower2 7y agoThe word "Just" is bending my mind! I guess it means we Just saw it, but it probably happened a while ago.
- crooked-v 7y agoFrom our perspective, it was 26,000 years ago - though for some takes on physics, it's easier to intuitively understand if you say "now, with a 26,000-year lag time on rendering updates".
- IggleSniggle 7y agoI prefer “now, from something 26000 years away”
- gumby 7y agoUm, shouldn't the headline say 25 Ky ago? It didn't "just" flare, unless "just" means "happened to for no known reason" which I suppose is a legit interpretation.
- Insanity 7y agoThe flare "just reached us" is the way this should be understood. Or well, we _just_ discovered it. But I guess it would make the title less appealing. Who would read "black hole flared 25000 years ago for 1 hour"? :P
- gumby 7y ago> Who would read "black hole flared 25000 years ago for 1 hour"? :P "We Looked Back In Time 25,000 Years and You Won't Believe What We Saw" "We Just Learned One Of The Last Things That Happened Before The Neanderthals Died Out and It Was Amazing" Fortunately science is slightly more immune to clickbait titles than other topics. Though only slightly.
- deleted 7y ago[deleted]
- antognini 7y agoFormer astronomer here! A lot of the comments here are about how this event occurred 26,000 years ago. I thought it would be useful to describe how we think about these things in astronomy. Firstly, yes it is true that this happened 26,000 years ago! More specifically, the event happened 26,000 years ago in our reference frame. There are other reference frames in which this event occurred two minutes ago or 5 million years ago. But generally these are not useful reference frames since the Earth's reference frame is not too different from the reference frame with respect to the center of mass of the Galaxy (we are not moving all that fast compared to the speed of light). That said, as astronomers we are not particularly interested in dating precisely when the event happened. 26,000 years is a very long time in human history, but it's not very long on astronomical timescales. Not very much has changed in the Galaxy over the past 26,000 years, so we don't gain much by dating it at the time the event occurred (with respect to the Earth's reference frame, of course). Furthermore, we wouldn't even know exactly when it happened even if we wanted to! Our clocks are very precise here on Earth, but our distance measurements to most celestial objects are very fuzzy, particularly the further away you get. Because of this, these sorts of events are always referred to with respect to the year they were observed on Earth. (Thus, the most recent nearby supernova is known as 1987A because it was the first supernova observed in 1987.) This all changes when you are studying more distant objects though! For very distant galaxies, we are now seeing things when the universe was considerably younger and things were much different. Then it becomes important to keep the event's age in mind. For these objects we will actually refer to their redshift. The redshift can be measured relatively well, and is related to the distance and age of the event via the Hubble constant and the acceleration parameter. Measuring these parameters is tricky and is a whole subfield of their own, so we usually stick with redshift as it is more related to things we can easily measure. A final note on the paper itself. These observations were taken at Keck on Mauna Kea. There has been a lot of controversy around the construction of the Thirty Meter Telescope, so the authors actually acknowledge indigenous Hawaiians specifically in their paper: > The authors wish to recognize that the summit of Maunakea has always held a very significant cultural role for the indigenous Hawaiian community. We are most fortunate to have the opportunity to observe from this mountain.
- sago 7y ago
- fermuch 7y agoI think this video does a great job at describing what happened, how, and the theories of why. https://youtu.be/Or8O_b7F640 https://youtu.be/Or8O_b7F640 Is there an object massive enough to make the black hole emit that amount of light, but which is not bright enough to be detected by our equipment?
- sixtypoundhound 7y agoThe Eye of Terror Pulsed... :)
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- Betty34 7y agoI have been seeing some strange calls from my wife phone and yet am unable to locate her phone or even get the number that have been calling her. i was so lucky enough that i went online to hire a hacker who was gonna help me in tracking my wife phone and also giving me access to her phone. while i was searching i saw webmaster6099@gmail.com as the best and i hired him this hacker was so good that he delivered me with my wife call logs, deleted call logs, all calls where recorded from last year till date i also had access to her text messages and also deleted messages. all this i had access right on my phone just with a very cheap price.
- chiph 7y agoCould this additional energy affect any stars near it -- possibly causing them to nova?
- philipov 7y agoTo the best of my knowledge, stars go nova because they have finished their fuel, and they can no longer sustain fusion once they begin fusing iron. It seems unlikely that being hit by a shockwave would trigger that. If it stripped away a lot of fuel, it would probably cause the star to go the route of a white dwarf rather than explode, right?
- novaRom 7y agoThis event is massive. We currently track nearby supermassive stars, so there is a chance we can observe a small change of their orbits.
- broth 7y agoOut of curiosity, is it possible that some cataclysmic event in the universe happened thousands of years ago that has yet to reach and potentially affect Earth?
- ypcx 7y agoI'm also interested. And adding to the question: Is it possible that this particular flare-up may be a forward echo of such an event? I.e. have we observed this happen before in other parts of the Universe?
- randie63 7y agoIt would need to travel faster than light
- numakerg 7y agoAccording to Wikipedia, there are six near-Earth supernova candidates. Effects range from destruction of the ozone layer to 3–4 °C of global warming. https://en.wikipedia.org/wiki/Near-Earth_supernova https://en.wikipedia.org/wiki/Near-Earth_supernova
- IvyMike 7y agoGamma ray bursts travel at the speed of light: https://en.wikipedia.org/wiki/Gamma-ray_burst#WR_104:_A_nearby_GRB_candidate https://en.wikipedia.org/wiki/Gamma-ray_burst#WR_104:_A_near...
- ahje 7y agoSomewhat related: Jack McDewitt's "The Devil's eye" is about a similar scenario.
- roywiggins 7y agoI like to play Bingo with comments on science stories: - "it was actually X thousand years ago" - "it's actually false color, why can't we see what it really looks like" - "surely this means quantum FTL communication works" - something casually eugenic and recently, with the Mauna Kea stories, there's a guaranteed "who do these bozos think they are, science is more important than anything"
- mrtweetyhack 7y agoMust have bee a good meal
- agumonkey 7y agoWhat are the chances that cosmic events of this kind could affect Earth ? say.. ironically massaging atmospheric state and climate change ?
- shkkmo 7y agoThere is evidence they have: > Based on the concentration of Fe-60 in the crust, Knie estimated that the supernova exploded at least 100 light-years from Earth—three times the distance at which it could’ve obliterated the ozone layer—but close enough to potentially alter cloud formation, and thus, climate. While no mass-extinction events happened 2.8 million years ago, some drastic climate changes did take place. [1] [1] http://nautil.us/issue/22/slow/the-secret-history-of-the-supernova-at-the-bottom-of-the-sea http://nautil.us/issue/22/slow/the-secret-history-of-the-sup...
- pts_ 7y agoWhy link to ad blogs instead of the actual study https://arxiv.org/abs/1908.01777 https://arxiv.org/abs/1908.01777?
- shkkmo 7y agoThe article has significantly different and more approachable content that explains the context of the paper. It also has a link directly to the paper at the bottom.
- stevespang 7y agoThis event happened over 250 centuries back in time
- jeffdavis 7y agoSeems odd that it would be a hunan-timescale event. Why not a few microseconds or a few million years?
- PopePompus 7y agoThe time scale is set by the orbital period of the innermost stable circular orbit (ISCO https://en.wikipedia.org/wiki/Innermost_stable_circular_orbit https://en.wikipedia.org/wiki/Innermost_stable_circular_orbi...). That period depends on the spin of both the black hole and the accretion disk, but the possible orbital periods range from 4 to 54 minutes for our galaxy's supermassive black hole. The period is proportional to the black hole mass, so for a really big black hole like the one in M87, the period is weeks long. That's part of the reason why the EHT imaged the M87 black hole, but has not produced a Sgr A* image - it takes many hours for the EHT to gather the data to produce an image, and Sgr A* is not stable on that time scale. It's like taking a long exposure of a foot race. But M87's black hole can't change much in a few hours.
- deleted 7y ago[deleted]
- softwarelimits 7y agoWhat software are these people using for the fantastic animations? Is there an established framework for astrophysics that allows to work on a high level to produce these nice visuals?
- thelittleone 7y agoIt's amazing given the lifespan of celestial entities that we can witness such significant change in such seemingly human time scales (2 hours). The milky way galaxy is estimated to be ~13.7B years old. The black hole was brighter for a 2 hours. That event, as a percentage of the milky way's age represents: 0.00000000000001666500016665%. As a comparison of what that represents as a unit of time in an average human lifespan (79 years) it equals: 0.00000069197080291971 seconds. 0.00069197080291971 milliseconds. 0.69197080291971 microseconds.
- simonh 7y agoI think a better comparison is to the size of the region in which this event occurred. For the event to appear to last only 2 hours to us, it can't have occurred in a region more than 2 light hours across. That's only 14 astronomical units, less than the diameter of the orbit of Saturn. There are stars bigger than that.
- redm 7y agoI'm always amazed at the amount of information and details astronomers can get from such a blurry little picture. It puts our galaxy's size in better perspective.
- deleted 7y ago[deleted]
- auslander 7y agoCould it be one of the Voyagers?
- logfromblammo 7y agoSo if the light from this event took 26 kyear to reach us, how long until the "om nom nom" sound reaches at least a Voyager probe in the interstellar medium? Well, supernova shockwaves can travel at up to 0.1c, so at best another 234 kyear. Keep your microphones ready.