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Astronomers see a black hole awaken in real time
- Waterluvian 2y agoIs there a convenient listing of the timeframe of cosmic events? I have a poor sense of when we’re talking hours, years, decades, millennia, MA, GA. Might make for a really cool static website project. Same with geologic events, too!
- rodolphoarruda 2y agoThe most relevant event to us here is the arrival of Trisolarans in about 400 years.
- djtriptych 2y agowhich event are you referring to?
- nashashmi 2y agoto go from a supernova to a black hole, it takes a couple of days. For a galaxy to be rearranged by a black hole, it take a couple of millennia. (my information is not precise nor the latest, so it could have been revised recently.)
- dylan604 2y ago> (my information is not precise you're in good company. most cosmological "dates" are not precise. for example, the age of the universe is suspected to be about 13.7 billion years +/- 20 million years. That's a really big +/- in years, but just 0.2% tolerance. the size of milky way is estimated at 26.8 ± 1.1 kiloparsecs. again, that's a lot of miles/kilometers of a range. it's not like they can run out and "pull tape" to take that measurement. it's one of my favorite quirks of astronomy. of course even the tolerances/variances are going to be astronomically large.
- lukan 2y agoI apologize in advance, but I still point to the relevant comic: https://xkcd.com/2205/ https://xkcd.com/2205/
- mr_mitm 2y agoI don't get it. Isn't precision always relative? Who cares how large the numbers sound in certain units?
- oh2aa 2y agoNo, precision or error can measured in absolute or relative terms. In either case, the unit is irrelevant, you could say +/- "0.000001 big bang timespan." The point is that in the realm of human experience, that tracking error is quite big.
- AnimalMuppet 2y agoCould you define what you mean by a galaxy being "rearranged" by a black hole?
- nashashmi 2y agoThe theory behind spiral galaxies is that a black hole of considerable magnitude and time lies right in the center. Gravitational waves spirals out for millennia. They start moving towards the center but also move towards each other. Closest stars move towards the center and other stars begin following the close stars and so on. This should ordinarily end up like an octopus with multiple arms extending from the center outwards. But then the Universe must also be rotating like a disc. And so the galaxy spirals out with curved arms instead.
- AnimalMuppet 2y agoSo, yes, we think there is a massive black hole at the center of all (or just spiral?) galaxies. And gravitational waves move at the speed of light, so if something changes the mass of the central black hole, and the galaxy has a radius of 25,000 light years, it will take 25,000 years for that wave to propagate out to the rim of the galaxy, rearranging things along the way. But: 1. The massive, central black hole did not come from a supernova. There are no stars anything like that big. 2. Even if there were a huge central mass and it collapsed, that doesn't actually change the mass distribution as far as the rest of the galaxy is concerned. There is very little change to propagate. The existence of the huge central mass would have already "arranged" the galaxy. 3. Galaxies spiral with curved arms due to their own rotation, not due to the universe's rotation. If the universe were rotating like a disk (and that was causing the spiral of galaxies), then you would expect the spin of galaxies to all be aligned. And they aren't; not at all.
- foota 2y agoFun fact, supernovae take only seconds to undergo extremely violent processes that typically result in their explosion. E.g., "Within a few seconds of the collapse process, a substantial fraction of the matter in the white dwarf undergoes nuclear fusion, releasing enough energy (1–2×10^44 J) to unbind the star in a supernova."
- jvanderbot 2y agoI've always wondered how realistic the timing was for the supernova explosion at the end of The Fountain. Seems they didn't do so bad!
- Fezzik 2y agoExtending the tangent: The Fountain is a criminally underrated movie!
- JamesHist 2y agohttps://www.historytimeline.com/timeline/universe/ https://www.historytimeline.com/timeline/universe/ https://www.historytimeline.com/timeline/geo-time-scale/ https://www.historytimeline.com/timeline/geo-time-scale/ DM if interested in the datasets.
- lukan 2y agoIt means not the creation of a black hole (like I initially thought), but an activity by the hole to blast out gas and energy. "In late 2019 the previously unremarkable galaxy SDSS1335+0728 suddenly started shining brighter than ever before. To understand why, astronomers have used data from several space and ground-based observatories, including the European Southern Observatory’s Very Large Telescope (ESO’s VLT), to track how the galaxy’s brightness has varied. In a study out today, they conclude that they are witnessing changes never seen before in a galaxy — likely the result of the sudden awakening of the massive black hole at its core." "Follow-up observations are still needed to rule out alternative explanations. Another possibility is that we are seeing an unusually slow tidal disruption event, or even a new phenomenon"
- logtempo 2y agoI guess "black hole awaken" is a more attractive headline than "black hole fart" ! It's really cool to see that we have so much instruments, we can actually monitor (a very small part) of the universe activity.
- q1w2 2y agoA more correct title is "Galaxy brightens and scientists suspect it might be due to the galaxy's black hole" There is no direct evidence the black hole is doing anything - it's just the only theory we have.
- johnnyanmac 2y agoI mean, when you put it that way black holes as a whole are a mere theory. A theory used to explain gravitational fluctuations and the odd lack of mass in the universe (which still wasn't fully solved and are currently dabbling with dark matter to further fine tune results).
- shiroiushi 2y agoExcept we've actually photographed a black hole: https://science.nasa.gov/resource/first-image-of-a-black-hole/ https://science.nasa.gov/resource/first-image-of-a-black-hol...
- revskill 2y agoI should know this 4 years ago
- api 2y agoWhat if we are quietly watching from a distance (in both space and time) as thousands of civilizations are helplessly irradiated to death by gamma rays?
- lukan 2y agoOr enlightened and transformed to a higher dimension? The answer is probably the same. We would not know and continue our daily chores.
- robofanatic 2y agoWhat we are watching right now has happened millions of years in the past.
- nikbackm 2y agoIt's not likely that life will survive long enough to form civilizations that close to a black hole. It has probably fed like this many times before already.
- denton-scratch 2y ago> that close to a black hole How close to a black hole? This isn't a common-or-garden black hole, it's supermassive. If it's (300M years ago) suddenly started producing intense radiation that we can measure here, then I assume that anyone in the galaxy that can see the central region is receiving a lot of radiation, as well as a storm of high-energy particles.
- greggsy 2y agoIt’s around 300 million light years away, so this technically occurred a long time ago in a galaxy far far away. With that in mind, I can imagine that millions of voices suddenly cried out in terror and were suddenly silenced.
- dylan604 2y agoSo what you're suggesting is that this might be a blast from the Death Star and we just saw Alderaan get wiped out?
- qwertox 2y agoCorrect link is now https://www.eso.org/public/news/eso2409/ https://www.eso.org/public/news/eso2409/ instead of https://www.eso.org/public/germany/news/eso2409/ https://www.eso.org/public/germany/news/eso2409/, which is leading to a login page.
- stronglikedan 2y agoMaybe regional. I'm not getting a login page in the US, but I am getting the German language page. Of course, I like your link better, since my German is very rusty (non-existent, really). Thanks.
- Udo 2y agoEven when I click on the correct link I get forwarded to the German page anyway. Granted, I'm in Germany, but I absolutely hate this behavior.
- Harmohit 2y agoI am in Canada and I still get the German page
- thenthenthen 2y agoI am in Hong Kong and get the German page
- NVHacker 2y agoAnyone else finds the "real time" attribute hilarious in the context of these cosmic events ?
- tekla 2y agoNo because light-speed is the speed of causality. It is by all definitions, real time
- mulhoon 2y agoYou’ve just blown my mind.
- yesbabyyes 2y agoAnother mind-blowing perspective is from that of a single photon; since time slows when approaching c, from its perspective it's eternal, and, since distance shrinks when approaching c, from its perspective it's also omnipresent.
- d1sxeyes 2y agoWell, it's not exactly eternal, it's that time is not passing for that photon. It's also (as far as I can tell) only correct to say that distances shrink as speed increases when you're talking about massive objects. A photon would not experience space contraction in any meaningful way.
- ImHereToVote 2y agoBy eternal you mean the photon will "experience" being a phonon when it's absorbed by matter?
- EncomLab 2y agoYou are conflating reference frames - it determines causality in your local reference frame but not in any other reference frame. The concept of "real time" - like all time - is entirely relative to the reference frame you are using.
- nashashmi 2y agoshower thoughts: Galaxies of stars are like people traveling through the cosmos together in one group. Elliptical galaxies have a direction of travel, that is why they are elliptical. A galaxy gets it first massive supernova, and a black hole is formed, and it becomes a spiral galaxy, kind of like when a seismic social event happens and everyone gets in line.
- spacecadet 2y agoshower thoughts: - bubbles in water act like black holes - the universe itself may only be a bubble among many - the multiverse looks like foam
- danparsonson 2y agoYou might enjoy this if you haven't already seen it: https://youtu.be/71eUes30gwc https://youtu.be/71eUes30gwc - TL;DW black hole density decreases with increasing radius, and the average density of the observable Universe is potentially greater than that of an equivalent-sized black hole, so maybe the whole Universe is inside one...
- gus_massa 2y agoNo. I tried looking for more details in https://en.wikipedia.org/wiki/Galaxy#Types_and_morphology https://en.wikipedia.org/wiki/Galaxy#Types_and_morphology but my conclussion is that it is a complicated topic.
- ImHereToVote 2y ago"Elliptical galaxies have a direction of travel, that is why they are elliptical" Huh?
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- mocha_nate 2y ago[flagged]
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- ycombinatorics 2y agoold news, happened already 300million years ago
- gigatexal 2y agoAhh so we saw the Simulators turn on a black hole in their Universe Simulator of which we are NPCs. ;-) In all actuality this is really really cool.
- ck2 2y agohttps://crowdmade.com/cdn/shop/files/Dev_Are_Watching_Shirt_-_Black_1800x1800.jpg https://crowdmade.com/cdn/shop/files/Dev_Are_Watching_Shirt_... ( https://www.youtube.com/watch?v=v-aP1J-BdvE https://www.youtube.com/watch?v=v-aP1J-BdvE ) ( alt https://www.pbs.org/video/what-if-physics-is-not-describing-reality-vtgkau/ https://www.pbs.org/video/what-if-physics-is-not-describing-... )
- gigatexal 2y agoI’m curious if the downvote was calling us all NPCs or the entire joke being not funny. I know we all try to be serious and contribute to the conversation here but come on it’s funny, no?!
- spacecadet 2y agoHacker news man, least funny place on the internet. Incoming down votes.
- ImHereToVote 2y agoAs it should be. If you want to spaz, you can always go to Reddit or 4chan.
- spacecadet 2y agoIm sure you are a hoot to hang out with. Hows it go? "Why so serious son"...
- ImHereToVote 2y ago
- _joel 2y agohttps://www.eso.org/public/unitedkingdom/news/eso2409/?lang https://www.eso.org/public/unitedkingdom/news/eso2409/?lang for British English users, sent me to the German page
- ajuc 2y agoSo if I understand correctly the black hole was there already, doing nothing, and then some matter was passing near it and started falling inside, releasing the surplus energy as radiation in the proccess?
- m463 2y agoI've always wondered what happens if two black holes run into each other? Can previously trapped matter somehow escape?
- ajuc 2y agoThe only way anything "escapes" from black holes is Hawking Radiation - virtual pairs of particles that appear and disappear constantly - can be split when they happen on event horizon - and that slowly drains the energy from black hole. https://en.wikipedia.org/wiki/Hawking_radiation https://en.wikipedia.org/wiki/Hawking_radiation If 2 black holes collide - they join together.
- DEADMINCE 2y agoI know this comment is old, but I was wondering if you could randomly explain something I've wondered about for some time. Doesn't Hawking radiation, since it exits a black hole, violate the idea that nothing escapes a black hole?
- 0xfae 2y agoEssentially, yes, but not exactly. My understanding is that particles and anti-particles pop into existence randomly, but quickly cancel each other out. Normally this doesn't affect anything, but if they happen to pop into existance right on the border of the event horizon, one will fall in and one will fall away. Thus matter is very very very slowly "leaving" the black hole. But not because matter inside is making it out, but rather because of some interesting quantum features of the fabric of spacetime.
- 2y ago
- newobj 2y agoWhat are the odds of being alive and having the technology in place to witness any galactic event, on the galactic timescale? That's just so wild to me.
- zakki 2y agoHow real time is it? Considering the light needs time to visit us.
- tamimio 2y agoProbably real time + 300 million light years latency.