[HN Gopher] A variable signal at heart of the Milky Way
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A variable signal at heart of the Milky Way
Author : wglb
Score : 266 points
Date : 2021-10-12 14:27 UTC (8 hours ago)
(HTM) web link (www.sciencedaily.com)
(TXT) w3m dump (www.sciencedaily.com)
| datavirtue wrote:
| I'm not saying it's aliens...but...
| shoto_io wrote:
| _Mr Wang and an international team, including scientists from
| Australia 's national science agency CSIRO, Germany, the United
| States, Canada, South Africa, Spain and France discovered the
| object using the CSIRO's ASKAP radio telescope in Western
| Australia._
|
| I just love how international Science is.
| [deleted]
| hungryforcodes wrote:
| What were you expecting exactly.
| drumhead wrote:
| Its always been that way, you read about how scientists in
| Germany and the Uk and France secretly wrote to each other
| during WW1 sharing their latest thoughts and discoveries.
| dboreham wrote:
| Surprised nobody has yet mentioned the book/movie "Contact"
| here.
| fsloth wrote:
| Business as well nowadays as software engineering teams can be
| easily distributed and travel and employment within EU is a
| non-issue. I have team members (at least) from Finland, Sweden,
| Estonia, Belgium, Romania, China, Germany, UK, New Zealand,
| Spain, Ethiopia - within company the interaction expands to
| teams and nationalities from US, France, India, Poland,
| Croatia...
| thanhhaimai wrote:
| For most things related to looking into space nowadays, we need
| a distributed team so we can cover the sky around the clock. It
| would be bad if we miss a 1 minute event "because it's daylight
| on our side".
| 867-5309 wrote:
| it might be bad for optical telescopes, but not radio
| telescopes fortunately
|
| I think it's more about sky coverage - which parts of the sky
| can be viewed from which telescopes at any given moment. that
| would require international collaboration
| [deleted]
| [deleted]
| GhettoComputers wrote:
| It mentioned its possibly a pulsar, it could just be a pulsar and
| magnetar https://en.wikipedia.org/wiki/Magnetar
| SeanFerree wrote:
| Very cool!
| donohoe wrote:
| New random number generator!
|
| "The brightness of the object also varies dramatically, by a
| factor of 100, and the signal switches on and off apparently at
| random. We've never seen anything like it."
| wrycoder wrote:
| It's sending pi, but we missed the first quadrillion digits.
| willvarfar wrote:
| Cloudfare famously uses images of a wall of lava lamps as a
| random number generator
| (https://blog.cloudflare.com/randomness-101-lavarand-in-
| produ...)
|
| Makes me wonder if photos of the sky are sufficiently random to
| be used this way? Does the image vary enough and does an
| attacker see a sufficiently different view even if really
| physically close? Etc.
| mcdonje wrote:
| That sounds like a non-trivial energy expenditure. Hopefully
| it's part of their office heating plan.
| gambiting wrote:
| It looks like there's 100 lamps. If they have regular 20W
| bulbs in them like any lava lamp, then that's just 2kW
| being used for this. Not nothing, but in an office it might
| as well be. That's less than a single AC unit. If you want
| to save energy in an office start by switching off
| equipment at night.
| mkr-hn wrote:
| It also helps serve the needs of millions of websites.
| This is like the mileage of a freight train: you have to
| look at how many tons it carries in that distance
| compared to alternatives. That's 2KW for easy true
| randomness. They have to get it some way, and this is
| probably the most efficient option for their purposes.
| willvarfar wrote:
| It's probably not literally the most efficient, but it is
| very good publicity. It is deliberately displayed behind
| the reception as a talking point.
| dTal wrote:
| It's _definitely_ not the most efficient. Let 's get that
| straight. Even within the space of "cameras pointed at
| chaotic systems", it's trivial to imagine less energy
| intensive chaotic systems than a rack of heaters
| convecting molten wax.
| treesknees wrote:
| From the end of the blog post, the LavaRand project was
| never actually used as a primary source of random
| numbers.
|
| >Hopefully we'll never need it. Hopefully, the primary
| sources of randomness used by our production servers will
| remain secure, and LavaRand will serve little purpose
| beyond adding some flair to our office. But if it turns
| out that we're wrong, and that our randomness sources in
| production are actually flawed, then LavaRand will be our
| hedge, making it just a little bit harder to hack
| Cloudflare.
|
| So, no, it isn't serving a purpose for millions of
| websites. It's 2kW of lamps running as a backup in an
| office nobody is going into right now to even look at.
| mkr-hn wrote:
| Yes, it is. I'm not sure what you think that post says,
| but it means LavaRand is currently serving a purpose in
| production. The whole point is to add more randomness to
| their other methods to protect against exploits or
| failures in the implementation of those methods. This is
| like the drives in a RAID setup. All those drives are a
| waste of power if you only care about when things work
| right. The point is to provide safety when things break.
|
| The previous paragraph:
|
| >> _" LavaRand is a system that uses lava lamps as a
| secondary source of randomness for our production
| servers. A wall of lava lamps in the lobby of our San
| Francisco office provides an unpredictable input to a
| camera aimed at the wall. A video feed from the camera is
| fed into a CSPRNG, and that CSPRNG provides a stream of
| random values that can be used as an extra source of
| randomness by our production servers. Since the flow of
| the "lava" in a lava lamp is very unpredictable,1
| "measuring" the lamps by taking footage of them is a good
| way to obtain unpredictable randomness. Computers store
| images as very large numbers, so we can use them as the
| input to a CSPRNG just like any other number."_
| treesknees wrote:
| But unfortunately it's not. In the analogy given in the
| comment I responded to, these lava lamps are a locomotive
| burning fuel while not actually moving any load. Sure
| it's there to "serve a purpose" if the primary breaks,
| but that doesn't mean it's doing any work when the
| primary is functioning just fine.
| mkr-hn wrote:
| This is the check on the primary. It moots the concern of
| whether or not the primary is working. You could turn
| them off, but then the system is open to all the
| vulnerabilities known and unknown this mitigates.
| dTal wrote:
| 2kW still seems like a lot compared to just putting the
| cameras in a lightless cardboard box, which will work
| just as well.
|
| This is energy spent because it looks cool, not because
| it's effective.
| ByThyGrace wrote:
| IANAC but any sufficiently secure RNG implementation should
| be inherently wasteful.
| BenjiWiebe wrote:
| It doesn't need to be inherently wasteful. A reverse-
| biased diode provides a completely unpredictable source
| of noise while also taking extremely little power.
|
| Or cranking up the sensitivity of a sensor.
|
| Or reading the low bit of an ADC.
|
| All of these provide good entropy sources without being
| wasteful.
| juancampa wrote:
| it's not _actual_ lava you know? Probably not significant
| NikolaeVarius wrote:
| Stop using your computer, its a non trivial energy
| expenditure
| lovecg wrote:
| If they use heating at all (and not just AC) and have a
| thermostat as everyone else it would automatically account
| for the extra heat and not run the furnace as much. This is
| also why a blanket ban on incandescent lightbulbs is silly.
| andbberger wrote:
| A blanket ban on incandescents is not at all silly. Your
| underlying assumption, that 100% is the peak efficiency
| for electricity to heat, is false.
|
| Heat pumps.
| lovecg wrote:
| Fair enough, I haven't considered that. I would still
| prefer a tax or something over an all out ban but that's
| a different conversation.
| andbberger wrote:
| why tho? given that there are more efficient ways to
| produce light and heat and there are drop in replacements
| for incandescents?
|
| Do you just prefer blackbody spectrums?
| techdragon wrote:
| It's more useful to take a sensitive detector and crank the
| sensitivity to maximum and put it in the dark. The randomness
| inherent in high iso noise on a cmos camera sensor is
| actually quite random. Adding actual stars to it might only
| decrease the randomness you might be able to see from the
| night sky without a telescope, in this case a radio
| telescope.
| mkr-hn wrote:
| Camera sensors have the same amount of noise regardless of
| ISO. It's just that bigger or better-engineered sensors
| have less noise period, so less is revealed as you raise
| the gain (ISO). I might have written a little about this:
| https://ko-fi.com/post/What-the-heck-is-ISO-A-sensitive-
| ques...
|
| The ideal for this would be an old sensor with lots of
| noise since anything new would have very little visible at
| any ISO. Maybe even the sensor in the camera they use for
| the lava lamps!
|
| A lava lamp has the benefit of being fully analog. There's
| no way to exploit it to make it predictable without
| physical access to mess with the chemistry to make the
| blobs stop moving around, and you'd have to do it to all of
| them without anyone noticing the blobs stopped blubbing.
| The camera on it 24/7 would make this a bit hard.
| lisper wrote:
| The source of your randomness matters much less than
| insuring that your adversary doesn't have access to it, and
| that you collect enough entropy from it. As long as you
| have a good lower bound on the amount of entropy per unit
| time that your source generates, and the source is secure,
| the physical details of the source don't really matter.
| JeanSebTr wrote:
| If that's intelligent life, they could then attack our
| encryption!
| papito wrote:
| Oh, haha, is THAT what's going to do it? :)
| mikro2nd wrote:
| Yes - They want our Bitcoins!
| eurasiantiger wrote:
| And here I thought intelligent life meant actual
| intelligence.
| rad_gruchalski wrote:
| What if other people use the same signal?
| [deleted]
| hasmanean wrote:
| All compressed data looks like random noise. If it didn't, then
| it wasn't compressed enough.
| hereforphone wrote:
| An RNG that all your friends and enemies also have access to
| [deleted]
| belter wrote:
| You can never be sure... https://dilbert.com/strip/2001-10-25
| simonh wrote:
| https://xkcd.com/221/
| zh3 wrote:
| I like to tell people who play the lottery they should go for
| 1 2 3 4 5 6 as it's just as likely to come up.
| sparks1970 wrote:
| But it's bad advice compared to a random selection because
| these are all numbers with meaning for people. Many people
| who enter lotteries use meaningful numbers such as days of
| birth. So 1 2 3 4 5 6 is just as likely as any set of
| numbers to come up but if you do win you're more likely to
| be sharing the jackpot with other people who chose the same
| set.
| extr wrote:
| But does it really matter? If you selected another number
| on that basis and then 1 2 3 4 5 6 won, you would still
| be kicking yourself as splitting the pot is better than
| no pot at all.
| bhelkey wrote:
| That is not a good strategy. That pattern is just as likely
| to come up. However, should it come up, you are almost
| guaranteed to split the pot.
|
| The best strategy is to not play. The second best strategy
| is to minimize the chance of splitting the pot.
| [deleted]
| FredPret wrote:
| My favourite of the Dilberts!
| gchokov wrote:
| The black hole eating stars, one by one.
| thedudeabides5 wrote:
| Like this person's guess, only speculation of what this
| actually is currently on the message board.
|
| If you were going to put a signal (that was also a puzzle to be
| unlocked), seems like the center of the galaxy would be a good
| place to make it emit from. Kind of obvious place to look.
|
| But yeah, would almost certainly fall into the black hole in
| the center in a couple million years or whatever.
| waltbosz wrote:
| Agreed that the center of galaxy is the best place to put up
| a billboard. Ha, what if that's all it was, an advert, "Be
| Sure To Drink Your Ovaltine." Galactic trolls, ha.
|
| Is the signal's data available publicly? I wonder what the
| cryptanalyst community would think of it.
|
| I would think that a intelligent species capable of placing a
| galactic billboard at the center of the galaxy would be
| intelligent enough to encode their message in an easy to
| decipher manner. Although, what does "easy to decipher" mean
| to a species with that technology. They may have stopped
| using any form of language that we would understand,
| generations ago.
|
| Is math a universal language? Could an alien species use a
| number system that we wouldn't recognize?
| dddw wrote:
| Intergalactic number station makes sense. Starting to sound
| like an episode of Lost
| [deleted]
| puzzlingcaptcha wrote:
| Lem's His Master's Voice comes to mind.
| _jal wrote:
| We have found OnOff!
|
| Beware the Emergence...
| skywal_l wrote:
| Love Vernor Vinge. Too bad is not as proficient as other world
| building science fiction authors, but if the pattern is
| correct, he should drop a new Zones of Thought book pretty
| soon.
| kabdib wrote:
| I've pretty much given up hope.
| throw1234651234 wrote:
| The part about the telepathic doggies was a downward slide
| anyway.
| nitrogen wrote:
| Have to disagree, the acoustically linked evolved
| hivemind concept was pretty mind opening for me.
| wildylion wrote:
| Acoustically linked __furries__. Pretty neat concept,
| really.
| TeMPOraL wrote:
| Can't hold this against him; he wrote the book way before
| furries were a thing.
| throw1234651234 wrote:
| He is probably in my top 5 after Stephenson and Gibson. He
| can't write aliens at all though. I skipped the alien half of
| a A Fire Upon the Deep (ok, skimmed) and missed nothing. The
| other books I tried by him were notably worse than that and a
| A Deepness in the Sky.
|
| As usual in these posts, recommend authors/books. Forever War
| is ok for central concept, author is meh. Haven't read
| anything decent recently.
| yodon wrote:
| I can't tell if you're saying you like or dislike A
| Deepness in the Sky. From my perspective it's among the
| most thoughtful portrayals of a truly alien species I've
| encountered (trying hard to be respectful here and not
| include spoilers for those who have not read it)
| sidibe wrote:
| > I skipped the alien half of a A Fire Upon the Deep (ok,
| skimmed) and missed nothing
|
| You mean you still liked the book. Hard to know whether you
| missed something if you skipped or skimmed it. I read this
| over 10 years ago but the aliens are what I remember most
| [deleted]
| carapace wrote:
| s/proficient/prolific/ ?
| himlion wrote:
| My first thought as well. Hope we can visit those spiders one
| day.
| MadameBanaan wrote:
| I'm not asking if someone has access to
| https://iopscience.iop.org/article/10.3847/1538-4357/ac2360 and
| could upload the article on SciHub ...
| perihelions wrote:
| https://arxiv.org/abs/2109.00652
| shoto_io wrote:
| Glad you didn't asked!
| [deleted]
| [deleted]
| rendall wrote:
| Is 'signal' the appropriate word, here? An astronomical term of
| art?
|
| Signal usually implies intent, doesn't it?
| detaro wrote:
| Not necessarily. E.g. analyzing data from natural events is
| still "signals processing", even though there is no intent
| behind an earth quake etc.
| awb wrote:
| Oxford defines "signal" as:
|
| 1. a gesture, action, or sound that is used to convey
| information or instructions, typically by prearrangement
| between the parties concerned.
|
| 2. an electrical impulse or radio wave transmitted or received.
|
| The second definition doesn't require intent.
| SideburnsOfDoom wrote:
| I doubt it. E.g. the headline "New gravitational wave detector
| picks up possible signal" (1) does not imply intent, just
| measuring a definite event and not just noise.
|
| 1) https://www.livescience.com/gravitational-wave-detector-
| stra...
| jcims wrote:
| Just something that I started doing the last couple of years,
| searching for for 'etymology of <insert word here>' instead of
| definition. It usually leads to pretty interesting and
| informative results, particularly when a word selection feels
| strained.
| pcmaffey wrote:
| Skip the search engine and just use etymonline.com
| guerrilla wrote:
| Wiktionary is excellent for this too.
| DiogenesKynikos wrote:
| "Signal" is used this way throughout physics. For example, CERN
| has an explainer on the search for the Higgs boson that says,
|
| > When physicists search for a signal of the Higgs boson, they
| select particle collisions with observed characteristics
| similar to those a Higgs production would feature.
|
| The "signal" comes from the process being studied, and the rest
| (at least whatever parts can be modeled stochastically) is
| "noise." One person's signal is another person's noise,
| depending on what each person is studying.
|
| 1. https://cms.cern/physics/higgs-boson-terms-and-definitions
| pavlov wrote:
| If you take signal as simply "discernible from noise", then it
| doesn't require intent or a unique sender.
| greenbit wrote:
| What's the frequency, Kenneth? What part of the spectrum are we
| even talking about here?
| ud_0 wrote:
| The ASKAP scans at 888MHz. From the paper, which luckily is
| publicly available:
|
| > _It exhibited a high degree (~ 25%) of circular polarization
| when it was visible. We monitored the source with the MeerKAT
| telescope from 2020 November to 2021 February on a 2-4 week
| cadence. The source was not detected with MeerKAT before 2021
| February 07 when it appeared and reached a peak flux density of
| 5.6 mJy. The source was still highly circularly polarized, but
| also showed up to 80% linear polarization, and then faded
| rapidly with a timescale of one day. The rotation measure of
| the source varied significantly, from -11.8+-0.8 rad m-2 to
| -64.0+-1.5 rad m-2 , over three days. No X-ray counterpart was
| found in follow-up Swift or Chandra observations about a week
| after the first MeerKAT detection, with upper limits of ~ 5.0 x
| 1031 erg s-1 (0.3-8 keV, assuming a distance ~ 10 kpc). No
| counterpart is seen in new or archival near-infrared
| observations down to J = 20.8 mag._
|
| https://arxiv.org/pdf/2109.00652.pdf
| gcr wrote:
| This is the plot of "The Island" by Peter Watts! See
| https://rifters.com/real/shorts/PeterWatts_TheIsland.pdf
| causi wrote:
| Thank you for posting that. Odd how it's so much different that
| most of Watts' writing. Normally I consider Watts to be in my
| category of "authors whose ideas are irresistible but whose
| writing style is tortuous" thanks to him fitting five or six
| metaphors and similes into every single paragraph, but that was
| an excellent read. I wonder if he intended it for a different
| audience than his usual. I wish I could get Blindsight and
| Echopraxia rewritten in that style.
| s1artibartfast wrote:
| To each their own. I always enjoyed the metaphors and
| ambiguity, even if it meant I have to re-read a page after
| going "wait, WTF just happened". Reminds me of poetry
| analysis or classic literature class. Understandingly
| frustrating if you just want to charge through and find out
| what happens.
|
| Gene Wolfe is also a master of this style, although he
| employs less metaphor, more ambiguity, and unreliable
| narrators.
| PicassoCTs wrote:
| https://www.tor.com/2014/07/29/the-colonel-peter-watts/
| uhtred wrote:
| I'm glad I am not the only one who finds his writing
| challenging. I had to give up on Blindsight after only a few
| pages as I had no idea what was going on.
| causi wrote:
| Which is sad because it really is an excellent plot, but ye
| gods is it a miserable read. There seems to be a
| correlation with how good an author is at world-building
| and plot-weaving and how much actually reading the work is
| a chore. Watts isn't the only one either. Peter F
| Hamilton's worlds are utterly enchanting but will make you
| want to hit him with his own books.
| mattkevan wrote:
| After ploughing through a few of Hamilton's books I came
| to the conclusion that three out of every five words
| could be deleted without any damage to the plot
| whatsoever.
|
| He's got some good stories, but I gave up after realising
| that I really didn't need to know what every character,
| no matter how minor, had for breakfast.
| wussboy wrote:
| Agreed. Like WoT, desperately in need of a fan edit to do
| what his editors wouldn't.
| UnFleshedOne wrote:
| Interesting, I haven't noticed writing style being
| especially challenging. Mostly because I'm not a native
| english speaker and read a lot of fantasy/sci-fi/etc
| books in english. They _all_ start off like "and then
| gromulars grokled grampors and fiddled fibbles
| flamboyantly" for several chapters. Then two things start
| to happen at the same time -- 1: author gets tired of
| introducing new things in fancy ways and goes on with the
| plot, and 2: reader slowly gets used to terms and
| concepts that are relevant enough to be used in the rest
| of the book.
| abakker wrote:
| I found blindsight pretty easy as an audiobook when
| driving rom SF to seattle. Maybe being slightly
| inattentive benefitted me for that style of writing, but
| I didn't notice the metaphor heavy style.
| causi wrote:
| Blindsight's not too bad, but Echopraxia really piles it
| on. For example, it takes nearly a full page to describe
| uneventfully passing through an entryway and it gets two
| similes and two metaphors.
| aetherspawn wrote:
| It comes up every now and then... but there were some theories
| that these completely random but strong signals could be from a
| "light sail beam emitter" that is very far away and that the
| randomness just depends on where they're going.
| shoto_io wrote:
| Do you have a source?
| aetherspawn wrote:
| The paper that calculated the rough size of the object that
| could be pushed by one of these random pulses was fascinating
| and was posted to Hackers News a few months ago, but I'm
| struggling to find it. I would like to read it again, and
| would appreciate if anyone has the link.
|
| The gist of the paper was that these beams would be plausible
| to push an object in the order of magnitude of the size of a
| spacecraft. But the calculated energy levels of the emitter
| (as we observe it) would require something like a dyson
| sphere, which would mean that if it were actually a light
| sail emitter, we'd expect a highly sophisticated
| civilization.
| HenryKissinger wrote:
| > The brightness of the object also varies dramatically, by a
| factor of 100, and the signal switches on and off apparently at
| random. We've never seen anything like it."
|
| A signal-emitting star being temporarily obscured by massive
| objects passing close enough to block the signal in our
| direction, or smaller objects at a further distance? Asteroids?
| Planets? Other stars? Dwarf stars? Maybe it's a crowded system,
| which may look like randomness.
|
| If I'm standing on one side of a busy road with a lamp aimed at
| you and you're on the other side observing the light, the
| seemingly random passage of vehicles will make the signal look
| random.
| sneak wrote:
| I don't think that explains the rotating polarization.
| HenryKissinger wrote:
| Maybe the source's rotation axis is responsible for this.
| eurasiantiger wrote:
| It would have to be spinning pretty darn fast to affect
| polarization of light in a detectable way.
| willvarfar wrote:
| Would these bodies cause detectable lensing?
| varjag wrote:
| The light is polarized, as I understand that very much excludes
| an ordinary star in such a system.
| jiocrag wrote:
| Dyson sphere.
| goatlover wrote:
| Dyson swarm.
| awb wrote:
| The pattern probably wouldn't be random then.
| dkarp wrote:
| Maybe it's still under construction
| lugged wrote:
| Maybe it's Morse code
| ddalex wrote:
| Maybe it's Maybelline
| typon wrote:
| "Random" is a very loaded word. If you were looking at some
| arbitrary nth digit of pi it would look random to you as
| well.
| hasmanean wrote:
| Some people will describe any non-periodic signal as
| random.
| mcculley wrote:
| Compressed or encrypted data should also look random.
| cantbudgeit wrote:
| I wonder if it is some sort of variation on a double pendulum
| problem.
|
| https://en.wikipedia.org/wiki/Double_pendulum
|
| Where the system is very chaotic and incredibly hard to model,
| so it appears to be random.
|
| Perhaps this is a complicated multi star system that contains a
| pulsar and the complex orbits are creating these seemingly
| random flashes of light.
| mig39 wrote:
| See also The Three-Body Problem
|
| https://en.wikipedia.org/wiki/Three-body_problem
|
| And it's also the name of a great book that might be
| appropriate here...
|
| https://en.wikipedia.org/wiki/The_Three-Body_Problem_(novel)
| Tenoke wrote:
| Traffic doesn't look random - you'd quickly note patterns in
| it. Ditto for movements of celestial objects.
| sosborn wrote:
| Does that hold true for something so far away? The number of
| objects that might pass through our line of vision only once
| during our life time seems as if it would uncountable.
| lrem wrote:
| The thing about outer space is that it's impressively
| empty. Any objects obscuring a visible star are most likely
| in its system. So, even for something this far away in a
| crowded system, we should be able to tell in a couple
| decades.
| penjelly wrote:
| the signal behaviour is curious
| hamparawa wrote:
| Aliens?
| hollander wrote:
| Waiting for the James Webb telescope to take a peek!
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(page generated 2021-10-12 23:00 UTC)