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The ‘Dyson Sphere’ mystery deepens: Star keeps dimming
- s_kilk 10y agoMy wager: It's a fleet of mega-spaceships passing across the star, probably much closer to us than to the remote star. Hence irregular dimming that doesn't seem to repeat predictably.
- jerry40 10y agoKeeping in mind that the star is 1480 light-years avay, the fleet passed across the star about thousand years ago. Or they're still flying toward us...
- bdavisx 10y agoAnd considering time dilation, it could be 10s or 100s of thousands of years before they would get here anyway (from our point of view).
- pmontra 10y agoOr very close to us, so even a relatively small fleet can dim a star. Not necessarily headed toward us.
- joeclark77 10y agoThey don't have to be right there by the star. They could be small ships just a few million miles away, maybe.
- GFK_of_xmaspast 10y agoSpace is, technically speaking, "really big".
- jawilson2 10y agoYou just won't believe how vastly, hugely, mind-bogglingly big it is.
- venomsnake 10y agoAn appropriate HG2G quote gets downvoted on HN ... the younguns have no respect and appreciation for the old masters.
- dalke 10y agoIt's 93 million miles to the Sun and 1/4 million miles to the Moon. "A few million miles away" places it very close by. Even a few billion miles is still inside the solar system. Pluto is about 4 billion miles away. It's difficult for something to stay between the Earth and a star and be nearby. The Earth moves around the Sun - this provides a baseline to measure stellar parallax, https://en.wikipedia.org/wiki/Stellar_parallax https://en.wikipedia.org/wiki/Stellar_parallax - and anything close to the Sun is also affected by it gravity. That "close" includes regions well beyond Pluto. "Occultations" are when one object blocks another. For example, detailed observations of when Pluto went by a star gave us clues that Pluto has a very thin atmosphere. Asteroids also cause occultations, see https://en.wikipedia.org/wiki/Occultation#Occultations_by_asteroids https://en.wikipedia.org/wiki/Occultation#Occultations_by_as... . They can be used to figure out the size of an object. That page shows an depiction of a occultation by Makemake, which is 50 AU out (further out than Pluto). Its shadow is on the Earth for only a few minutes, and it's over 1400km across.
- joeclark77 10y agoI just keep hoping they'll get here before November, though, so I can write in Kodos on the ballot.
- clouddrover 10y agoIt might just be a problem with the data: http://www.abc.net.au/news/2016-10-04/kepler-data-glitch-not-aliens-could-be-to-blame-for-whacky-star/7889306 http://www.abc.net.au/news/2016-10-04/kepler-data-glitch-not...
- chiph 10y agoThis brings to mind the Omega clouds from Jack McDevitt's novels, starting with: https://en.wikipedia.org/wiki/The_Engines_of_God https://en.wikipedia.org/wiki/The_Engines_of_God
- dsq 10y ago...which in turn are reminiscent of Fred Hoyle's "The Black Cloud".
- jcfrei 10y agoThis is very unlikely. See previous HN comment: https://news.ycombinator.com/item?id=12240401 https://news.ycombinator.com/item?id=12240401
- mcv 10y agoProbably on their way to us, which is why they're directly between us and their star.
- krige 10y agoMy wager: The star is being eaten by a cosmic horror called Hellstar and it will be soon coming our way. Now excuse me while I take off my Junji Ito hat.
- kabdib 10y agoOr a space goat. My money is equally split between a Dyson sphere that is tearing itself apart (because: low bidder on the project, some things just never change) or a gigantic space goat that is eating the star. Both are equally likely :-)
- simonh 10y agoStarkiller Base powering up!
- tonetheman 10y agoexactly what i was going to say!!!!!
- trm42 10y agoUnicron, devourer of worlds!
- jlebrech 10y agoso there are in the middle of building the dyson sphere?
- isaiahg 10y agoThat's the idea. Or the dyson sphere is made of a mesh network of multiple parts with varying levels of density.
- jlebrech 10y agowe could build own own dyson sphere, just (sic) start off by turning ISS into a solar collector and making it face the sun 24/7. then add more to it.
- blackflame7000 10y agoElon Musk just needs to merge SolarCity with SpaceX and were in business.
- hetman 10y agoThis was in fact the original concept as envisioned by Dyson. He pointed out that a solid sphere would be mechanically impossible but the logical way to build such a structure would involve a "swarm of objects".
- jameskilton 10y agoMy issue with the whole "alien civilization" idea is that we are seeing what happened around that star some 1,400 years ago, which means if they were building a Dyson sphere that long ago, it's unimaginable what tech they have today. I have a hard time accepting that an intelligent species could be that far ahead of us technology wise, but I could be wrong!
- minitech 10y ago1,400 years is really small compared to the history of life on Earth. It doesn’t seem all that unlikely that other planets might have had millions of years of head start.
- mckoss 10y agoWhy not just a binary dwarf sucking material (somewhat chaotically) out of its more luminous twin?
- simcop2387 10y agoWe'd see bits of time where the dwarf was in front of the twin and burning much much brighter, the accretion disk on the dwarf would be larger than the dwarf and giving off high energy photons as it consumes the incoming matter. We haven't seen any spikes in the light level, only dips. It's possible it's behind the other star still but I don't think we've seen anything else to indicate that.
- joeclark77 10y agoMaybe it's Slartibartfast's workshop.
- littlegreenb18 10y agoIt's Morning Light Mountain
- markild 10y agoHe.. She.. It.. They? Didn't create the sphere though! To anyone not getting the reference, read Pandora's Star by Peter Hamilton[1]. It's a lovely read. [1]: https://en.wikipedia.org/wiki/Commonwealth_Saga https://en.wikipedia.org/wiki/Commonwealth_Saga
- soylentcola 10y agoGood timing because I just started this last week after finishing Vinge's "Zones of Thought" series. I guess I'm on something of a space opera kick lately.
- daveguy 10y agoAre the sequels/prequels worth reading? I read the first one last year and enjoyed it, but the follow up reviews made it seem like the others novels might spoil it.
- karmajunkie 10y agoI thought the prequel was pretty good. Less into the sequel though.
- mikeash 10y agoThe first two are great. Deepness is the best one, IMO. As for anything beyond that, I'll just say it's so sad he stopped at two.
- etatoby 10y agoIn that case, let me recommend the Vorkosigan saga, if you haven't read it yet. One of the best book series I've ever read, definitely the best among space opera. Start with Cordelia's Honor https://www.amazon.com/-/dp/0671578286 https://www.amazon.com/-/dp/0671578286 Edit: various books from the series won 4 Hugo awards, 2 Nebula awards, and were nominated a dozen of times.
- delecti 10y agoAs a really crazy thought, is it be possible that networks of Dyson Spheres throughout the universe would explain the lower level of visible matter vs the gravity we observe? That is, Dyson Spheres obfuscating their contained stars as an explanation for dark matter? Similarly, the heat would still escape from them. Could that explain the CMB? (I expect that I'm way off the mark, but if nothing else it could make for an interesting premise for some sci-fi.)
- dandelany 10y ago> Dyson Spheres obfuscating their contained stars as an explanation for dark matter No - MACHOs have been pretty well ruled out by now. "Several groups have searched for MACHOs by searching for the microlensing amplification of light. These groups have ruled out dark matter being explained by MACHOs with mass in the range 1×10−8 solar masses (0.3 lunar masses) to 100 solar masses" (https://en.wikipedia.org/wiki/Massive_compact_halo_object https://en.wikipedia.org/wiki/Massive_compact_halo_object) > Similarly, the heat would still escape from them. Could that explain the CMB? The CMB comes from everywhere at once, uniformly, all the dark spaces in between stars is glowing. Dyson spheres radiating heat would just look like a bunch of dots glowing in the infrared. I don't see how any number of Dyson spheres radiating heat could produce a continuous, uniform field.
- deleted 10y ago[deleted]
- delecti 10y agoYa know, gravitational lensing and the relative uniformity of the CMB are such succinct and (in retrospect) obvious debunking of those ideas that I almost feel embarrassed to have suggested them. :P Thanks for the awesome response.
- dandelany 10y agoDon't feel bad, there is a name for "MACHOs" because so many scientists have had similar hypotheses about dark massive objects :)
- neals 10y agoSo interestingly, hiding you star in a Dyson sphere, turns it into the loudest beacon in the galaxy, for a while. If we wanted to be 'found' by aliens, we should do this to our sun.
- jerry40 10y agoAlso we can use this as a trap. Just choose a star, make it darker and wait.
- drzaiusapelord 10y agoA trap for what exactly? By the time your society can do this to a star, you're not exactly fighting others for resources. You're very much into post-scarcity territory and the traditional motivations for conflict are long gone. I never understood the scarcity mentality we apply to hypothetical super-advanced civilizations. This is like expecting Jesus to take your wallet or the Buddha to kick you down the stairs. If there are other advanced societies out there I seriously doubt war is their main motivator in space exploration, the same way Voyager and Curiosity are unarmed. Sure, that makes for fun sci-fi stories, but real life is governed by fairly simplistic game theory rules, at least from a high-level perspective. The motivators we have been given through evolution will be the motivators they have as well. Unless we're dismissing evolution as only a local phenomenon, we should expect similar beings to ourselves. I think the 'hostile alien' scenario shouldn't be our default. Sadly, that approach sells ad impressions and schlocky futurist books and influences a lot of people to believe things that are pretty questionable. If we discovered a primitive species in the European seas we'd be tripping over ourselves to preserve them and study them and to make sure they never, ever get hurt by us (or a stray asteroid or anything we could prevent). We wouldn't be conquering them with robot subs for their pretty coral jewellery or sub-surface oil or whatever. We have enough pretty things and energy here on Earth and in unihabited places if need be. Life is rare enough that we don't need to attack other life for resources, assuming we ever find any.
- thaw13579 10y agoHaven't atrocious things been done during "exploration" on Earth, e.g. European imperialism and colonization? I'd like to think humanity has moved past that, but there currently seem to be enough war torn areas to show otherwise...
- _andromeda_ 10y agoIf "By far most of the solar system's mass is in the Sun itself: somewhere between 99.8 and 99.9 percent", then I can't help but wonder if there is enough matter to cover the sun's surface area to create a real Dyson sphere. Where would this matter come from? Is there enough matter in left in the 0.1% (shared by the rest of the solar system) to completely engulf the sun?
- piker 10y agoThe sun is quite dense. I have to think a Dyson sphere surrounding it could be as thin as, say, an onion's outer layer when compared to the onion itself. (Assuming enough distance from the sun to avoid burning up.)
- _andromeda_ 10y agoSomewhat true, but it still seems to me that the only way to build a proper Dyson sphere would be to not only achieve scientific breakthroughs that allow for interstellar travel, but to do so in a way that allows us to be able to ferry as much matter from other stellar systems as we need.
- venomsnake 10y agoor you can just harvest the heavy elements from the sun itself. Bonus - you prolong its life.
- _andromeda_ 10y agoPerfect! That would work.
- adrianN 10y agoThat depends on how thick you want your cover to be.
- api 10y agoDyson swarms are a far more practical idea than spheres and can be incrementally constructed. It's basically just a ton of satellites.
- test6554 10y agoOccam's razor: If you see mysterious dimming in a star, it's definitely aliens.
- perseusprime11 10y agoOccam's razor suggests to me that the problem is on our end. We still don't fully understand the Universe.
- s_kilk 10y agoThe implication seems to be that construction is ongoing, and the pieces of the sphere are being moved into place.
- test6554 10y agoA cloud of circumstellar material could be the explanation but no simple cloud model can explain the strange transit ingress and duration that has been observed.
- haneefmubarak 10y agoOr rather, since all stars are multiple light-years away from us, construction was ongoing.
- drjesusphd 10y agoA suitable definition of "now" is our past and future light cones.
- clock_tower 10y agoIt's 1480 light-years away; if any construction occurred there, it was ongoing in 536 AD. For reference, this was during the First Gothic War (Belisarius' reconquest of Italy); if the Battle of Mount Badon (somewhere between 482 and 500 AD) actually occurred, it would have been in living memory...
- dave_sullivan 10y agoBlackhole starlifting makes more sense to me than Dyson spheres (see section on star lifting): https://arxiv.org/abs/1104.4362 https://arxiv.org/abs/1104.4362 > Importantly, researchers have concluded that a thin accretion disk around a rotating black hole is the most efficient power source in the universe , a process up to ~50 times more efficient than nuclear fusion occurring in stars (e.g. Thorne 1974; Narayan and Quataert 2005). If any civilization is to climb the Kardashev scale, it would certainly at some point want to master that energetic source. We call such an endeavor black hole star lifting Instead of a Dyson sphere, you're using a black hole (and apparent mastery of gravity) to leech energy directly from the sun.
- fuzzythinker 10y agoOne can't get to the most efficient energy source without bootstrapping. And dyson swarms may be one of the easier ways to get there. I like this video [1] that explains this pretty well, from dyson swarms to kugelblitz. I do not understand enough from the paper to know the difference between kugelblitz and black hole star lifting though. [1] https://www.youtube.com/watch?v=jW55cViXu6s https://www.youtube.com/watch?v=jW55cViXu6s
- etatoby 10y agoPBS Space Time FTW! I'm waiting for their take on this star.
- ge96 10y agoAlright, now we know how that weapon works in Star Wars Ep 7
- fuzzythinker 10y agoYou mean like how the laser moves at approximately the speed of sound?
- ge96 10y agoShhh... That was for suspense, it's more of a "plasma slug" weapon
- jasoncrawford 10y agoHere's a better explanation in a long (but readable) series of posts from an actual astronomer, Jason Wright: http://sites.psu.edu/astrowright/2016/08/30/what-could-be-going-on-with-boyajians-star-part-i/ http://sites.psu.edu/astrowright/2016/08/30/what-could-be-go... In this series he details several hypotheses and ranks them.
- daveguy 10y agoThis is a series of posts with the summary and index here: http://sites.psu.edu/astrowright/2016/09/03/what-could-be-going-on-with-boyajians-star-part-x-wrapup-and-gaias-promise/ http://sites.psu.edu/astrowright/2016/09/03/what-could-be-go... Initial guide here: http://sites.psu.edu/astrowright/tabbys-star-posts/ http://sites.psu.edu/astrowright/tabbys-star-posts/
- mcv 10y agoThat is a really interesting and thorough examination of all possible explanations, as well as a fun (if long) read.
- brador 10y agoIf I was building a Dyson sphere I would launch multiple modular solar panels into orbit around the star. This is the cheapest scalable way to do it while I collect resources and send more as my energy needs increase. The problem then is getting that energy out. I'd use lasers from my panels to my planet. That means my solar panel collective in orbit around the star will have to always point to my planet for maximum efficiency so I don't have useless panels since there's no way i'm building a battery at star energy scale on each panel. The dimming you see would then be based on the orbit time of my planet around the star, since the panel half halo will always be pointing at my planet. Essentially geostationary around the star.
- chanandler_bong 10y agoI still say it is a giant alien Aldis lamp, and we just don't understand their Morse code.
- mmmBacon 10y agoMeasuring absolute brightness is hard. It would be good to compare the measurement error is in brightness of a reference star of about the same magnitude and distance(and even perhaps a known variable star) to the observed changes in this star. In the lab under ideal conditions with ideal light sources, it's pretty common for there to be >2.5% error in these types of measurements. For those used to dB unit, this is a ~0.1dB change. In optics, it's very easy to introduce error at this level.
- lordnacho 10y agoSo if you make a Dyson sphere, your planet is either inside or outside of it. If it's outside, you might get complaints about the shutting off of the day/night cycle. If it's inside, you get all the sun's light reflected off the inside of the sphere. Kinda blinding.
- gpderetta 10y agoyour planet (and most of the solar system) has been dismantled to build the Dyson sphere, the system is now ruled by DAO-like AI agents running on computronium. You upload yourself and a few other survivors on a small can-sized spaceship and flee the system in search of a new home.
- humbledrone 10y ago/endsynopsis "Accelerando", Charlie Stross (2005)
- mcv 10y agoWhy would light be reflected? The point is to convert it to energy as efficiently as possible. If they can do that with 99% efficiency, there's not much left to reflect. But by the time you're building a Dyson Sphere, the vast majority of the people are probably already living in space habitats. There's not much use for stellar-scale energy if everybody still fits on a single planet.
- trelliscoded 10y agoFor anyone who has some spare time, here's an enormous time sink: http://www.orionsarm.com http://www.orionsarm.com Don't click on that if you have stuff to do today.