12 ms·

BLC1: A candidate signal around Proxima

92 points by weare138 6y ago

optimalsolver 6y ago
"""Unfortunately, this news leaked out before the team had finished their analysis, so we’re left to read tea leaves and parse vague newspaper statements instead of reading their paper on the topic (which does not exist because they’re not done with their analysis!) Someone in the “astronomical community” (we don’t know if they are even a member of the team) leaked the story to the Guardian. Their hand having been forced, the team then gave interviews to Scientific American and NatGeo with some more details, emphasizing that the signal is probably RFI. Now, I’m pretty grumpy about this. SETI has extensive post-detection protocols that were not followed by the leaker, exactly to avoid this sort of situation. Especially since the team was definitely going to announce this, there’s no need for the leak.""" --- It's a bit amusing that after decades of SETI touting their post-detection protocol, they couldn't even keep a sorta-maybe interesting find under wraps for five minutes before someone went running to the media. Where's Jodie Foster when you need her?
- zarmin 6y ago
  No words. Should've sent a poet.
- dvirsky 6y ago
  Well, at least we can be certain that there hasn't been any contact made before that's been kept secret for decades.
  - KMag 6y ago
    > we can be certain that there hasn't been any contact Conspiracy theories always find a way. Someone can believe that 5G causes COVID (and equally inexplicably, 4G doesn't) can believe this is still part of a cover-up.
    - wyldfire 6y ago
      Those theories are bogus however under the big umbrella of technologies in '5G' are new frequency bands. Those bands may have different absorption characteristics in tissue than previous ones. Buuuuuut they're not viruses, and they're not used for 'spying' any more or less than 4G.
      - rsynnott 6y ago
        Most 5G is at LTE-ish frequencies. The mm-wave stuff is relatively rare and will probably remain so for a while (if not forever; it’s arguably a solution in search of a problem).
        wyldfire 6y ago
        I know that. And you know that. But it's a kernel or truth that conspiracy theories are able to weave their way about.
        ithkuil 6y ago
        Yeah. Sadly you can always find something somewhere at some point in time that proves the general point of "the government and corporations being assholes". Like when lead poisoning was covered up by corporations and researchers discredited by corrupt "scientists". Yes this happened, and society learned from such incidents and became more resilient. But if you keep getting back at those incidents as "proofs" that everything is corrupt forever, how you're going to solve the problem?
        DaiPlusPlus 6y ago
        > mmWave I thought the problem was that houses and most buildings outside of North America have solid internal walls which blocks or attenuates mmWave signal strength to such a degree it's practically worthless for anything besides Wi-Gig between consumer appliances within a few feet of each other?
        6y ago
- kordlessagain 6y ago
  I wonder how many RFIs have been noted to be in the 982Mhz band, especially given we don't know how to transmit at that frequency? > “We don’t know of any natural way to compress electromagnetic energy into a single bin in frequency” such as this one, Siemion says. [1] [1] https://www.scientificamerican.com/article/alien-hunters-discover-mysterious-signal-from-proxima-centauri/ https://www.scientificamerican.com/article/alien-hunters-dis...
  - yholio 6y ago
    You might have misread that: we don't know any natural process that would generate a single spectral line at that frequency, but it is very easy to generate artificially by a civilization. Hence, the interest. You can build an oscillator at that frequency with 10$ in parts.
  - lovecg 6y ago
    I think that says that we don't know of any naturally occurring sources that would do that, not that we don't know how to generate this signal if we wanted to (which should indeed be trivial).
  - VLM 6y ago
    How many unclassified RFI sources around 982 MHZ is the only question we can answer. Its in the L-band for satellites up and down by numerous countries and on the ground there's interesting TACAN and military digital links. Its entirely possible nobody can admit for fifty years that some classified digital data link device had a firmware crash and transmitted an unmodulated carrier for awhile.
    - boznz 6y ago
      Not every country enforces radio spectrum guidelines. I made some 868Mhz lora sensors for a pacific island client in 2016. The customer had a lot of interference from the local TV station and after talking to the island mayor we just changed them to 877Mhz which was quiet
    - adinb 6y ago
imglorp 6y ago
It seems that lunar darkside observatory can't come soon enough: it would be immune to much of this suspected human interference. It would also be relatively easy to set up with existing robotic rover tech, laying long runs of wire on the surface.
- Already__Taken 6y ago
  would it even be useful just to put and antenna pointing at earth from the moon just to transmit "this is the noise floor of yourself" later add a dark side listener to difference the signals?
- giantrobot 6y ago
  Lunar observatories are awesome in theory but very face a lot of issues in practice. The first is just lifting their mass. The 64m dish at Parkes observatory weighs in at about 1000 tons [0]. An expendable Falcon Heavy can lift about 26t to GTO which is a bit more than it could put into a TLI. Let's say 22t into TLI. That vehicle needs to actually land on the Moon rather than orbit or crash into it so usable payload to the Lunar surface will be much less than the vehicle/fuel mass. Let's say 14t since it's all unpressurized payload. That's for $150m a pop. You'll need at least 71 of those launches which comes out to a cool $10.6b. The construct-o-bots will need a few more launches so let's round up to $11b. That's all assuming building a huge instrument on the far side of the Moon with robots is all a solved engineering problem. Then there's the Lunar environment. The reason the Moon is covered in Moon dust is because it is constantly bombarded with micrometeoroids. I'm pretty sure the operating manuals for a lot of the sensitive instruments mounted on the Parkes dish say "don't shoot with a gun" which is about the energy equivalent of a lot of micrometeoroids IIRC. One hit to a cryogenically cooled receiver will result in it ceasing to be cryogenically cooled. That tens of billions of dollars for one Parkes equivalent could buy you about 60 FASTs (~$170m) or 30 Arecibos (~$350m).
  - imglorp 6y ago
    I was not proposing carrying a dish, instead lay long runs of wires on the surface in whatever pattern you like. But if you want a parabaloid, chose a darkside crater and do the Arecebo thing there. Also, some frequencies are not possible on Earth at all due to ionosphere attenuation.
yodsanklai 6y ago
As much as I love science fiction, I fail to get excited about this type of news. I'm convinced that intelligent life is pervasive in the universe, and also that we're not going to interact with them in any way.
- api 6y ago
  Why? We haven’t been looking very long or very hard.
  - agar 6y ago
    That we have not looked long or hard is why we have not (yet) found a signal. Interacting with an ETI will be much more problematic than finding a signal, given speed of light issues. Or did you misread the OP? He believes ETI is pervasive, which seems a reasonable conclusion to extrapolate as Kepler fills in the F(p) and N(e) terms of the Drake equation.
  - jacobwilliamroy 6y ago
    It's a chilling indictment of the human race that all our tools for detecting intelligent life are pointed AWAY from the earth. That's a real red flag, and it would make sense that others would see that and refuse to talk to us. Tangentially, we put almost no effort into interspecies communication. It's asinine to be constantly searching for intelligence when we can't even figure out how to communicate with cetaceans. By now we should have a full functioning networked dolphin-computer interface and dolphin web forums and interspecies instant messenger. But NOOOOOOO, we're all too busy literally shouting at the sky.
    - mwcampbell 6y ago
      Or we could be trying to communicate with parrots (and preventing some species of them from going extinct), as suggested in Ted Chiang's short story "The Great Silence".
      - jacobwilliamroy 6y ago
api 6y ago
I love the rationale for Proxima maybe being the most likely star to be transmitting directly toward us. Maybe it’s a carrier signal for an alien equivalent of a public HAM repeater or a peer to peer mesh net node. It would effectively be a dial tone. Each node broadcasts toward, say, its three nearest neighbors. It sends a carrier that also periodically encodes info about how to use the node and the “IP addresses” of other known participants. Latency would suck though. A complete ping to another “live” station could take hundreds or thousands of years. The vast majority of repeater nodes could be dumb unmanned devices periodically sent out and placed in orbit around other stars. What if our solar system has one and we haven’t noticed it because it’s not that big, is in close solar orbit to easily harness a lot of power, and is only aiming its signals at our three nearest neighbors. Heh.
- WJW 6y ago
  I like this idea! (though I don't think it's likely) Imagine if the creators of such a system have lifespans of tens to hundreds of millions of years and so could feasibly get somewhere in the galaxy even when travelling at sublight speeds. We'd be so alien to them that they likely wouldn't even think to look for us.
  - api 6y ago
    I’m more imagining a collaborative effort much like amateur radio networks. Once you start talking you learn about the net and how to help add more nodes, etc. The node at Centauri might not be from there, but it might be from someone within a few hundred light years who has volunteered to maintain repeaters in their neighborhood. If we came online we would have to generate a call sign (however that is done, instructions repeated along with the carrier) and then start saying hi to nearby HAMs. There would probably be some forum etiquette. Might be a good idea to lurk a while before posting an intro thread. “Oh, look, another n00b asking about how to do net positive fusion power... read the FAQ on the wiki. Nearest mirror is at...”
    - WJW 6y ago
      With our luck the nearest mirror is 500 light years away and by that time we'd have figured it out ourselves. Oh well... :)
jimmcslim 6y ago
The Trisolarans are calling us...
- geoah 6y ago
  Do you think Ye Wenjie was right to tell them to come over?
baggy_trough 6y ago
982.002 MHz frequency indicates a likely human origin, since aliens or Mother Nature would not be sending an integer number of MHz.
- urbandw311er 6y ago
  As it states in the article.
- Someone 6y ago
  If we assume there are zillions and zillions of extraterrestrial intelligences broadcasting radio, chances are at least a few zillion base their unit of time on periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the caesium 133 atom (https://en.wikipedia.org/wiki/Caesium_standard https://en.wikipedia.org/wiki/Caesium_standard) Such civilizations would have a unit of time that’s a rational number of seconds. That would make such clashes possible (but very likely not likely, depending on how likely it is that a civilization uses caesium 133 as the basis for its clocks)
  - seppel 6y ago
    > chances are at least a few zillion base their unit of time on periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the caesium 133 atom Of exactly 9192631770 Hz...
    - tatersolid 6y ago
      Do those values depend on the strength of the local gravity well?
- VLM 6y ago
  Its unmodulated and nobody in the article or comments is willing to consider non-communications situations for both earth and alien sources. Its entirely possible someone out there (us, or ... them) has a nice magnetron (or more exotic tech) pumped main engine or station keeping thruster that uses microwave energy to boost exhaust temp and thus specific impulse. Then given that as propulsion tech, its possible that a boring engineering specification like "make the nozzle two space alien foot lengths in diameter" which is a nice round measurement to a space alien, is in fact 982.blah MHz to our measurements. Certainly no one cares that their terrestrial microwave oven operates at 2.45 GHz, all they know is it pops popcorn. And in a like manner, some microwave boosted propulsion system, either an earth or alien source, might just randomly end up on 982.blah MHz but the number means nothing to anyone, its just what fell out of the thruster design reqs. Say I was building a microwave pumped thruster, I'd make the nozzle less than a tenth wavelength at pump frequency to contain any leakage RF while letting white hot plasma stream out. 982.002 MHz would be 30.5 cm in a vacuum, so figure my engine nozzle diameter would be about 3 cm across for minimal leakage. You're probably not going to get a huge amount of thrust out of something 3 cm across, so its probably a station keeping thruster at most not some main acceleration thing. Besides a couple hours of thrust would imply going very fast if it was a main thruster but some minor course correction / station keeping thing could run a couple hours. So its entirely likely some space vehicle had a pretty substantial failure of a course correction thruster. Another topic no one is willing to discuss, which is a bit weird, is the old fashioned superheterodyne topology works pretty well, so 982.002 MHz is not the frequency of operation, its something in a local oscillator chain of a receiver (or transmitter) that works somewhat above 1 GHz. Another "where are the EEs" comment is 982.002 is possibly not an INTENDED local oscillator output but someone's class B or class AB output stage had a single transistor failure and what was outputing a great low distortion signal at 491.001 is now outputing an icky harmonic signal at 982.002 or similar after the output section failure. Just because the 15th harmonic of the FM sound carrier of an old fashioned analog low-band VHF tv transmitter on USA allocation channel 3 could fall less than 1% off from 982.002 but doesn't prove it is the source and probably is not, the point is we could be observing a failure mode or unintended interference.
biggestlou 6y ago
I'm still looking for intelligent life on this planet!
credit_guy 6y ago
> “If there is intelligent life there, it would almost certainly have spread much more widely across the galaxy. The chances of the only two civilisations in the entire galaxy happening to be neighbours, among 400bn stars, absolutely stretches the bounds of rationality.” This is a fallacy. If there's life all over the galaxy, then we'd be the most likely to detect radio signals first from our closest neighbors. Interstellar distances are, well, astronomical. Proxima Centauri is 1700 times farther from us than Voyager 1 (which was mentioned in the article). Because of the quadratic decay, a Voyager-type source in Proxima Centauri would send to us a signal more than 3 million times weaker. A star that is 10 times farther still will get a dimming of the signal of a factor of 100 on top of this. So, if there are aliens habitating the planets of all the stars around us, probabilistically we'd expect to first detect the signals originating with the closer among them.
- m4rtink 6y ago
  Thats why I'm thinking megastructure waste heat and weird planetary and stellar orbits (klemperer rosetete[1]) or some periodic high energy events (drives, fireworks, "disputes") will be how we find out about the more interesting advanced neighbors, possibly missing many closer ones who don't influence their environment too much yet.
  - Mediterraneo10 6y ago
    Back in the 20th century, I might have said the same thing when I was enamored with Larry Niven’s hard sci-fi. Nowadays, I find it hard to entertain the possibility of civilizations much more advanced than our own: the persistently dismal news and noticeable slowdown in materials-science technological innovation since the turn of the millennium, makes me suspect that races inevitably hit the Great Filter around the point where we are now. After all, hasn’t it been noted that science-fiction is no longer as optimistic about technological progress as it used to be?
    - m4rtink 6y ago
      I think it's not that bad scientific progress wise if you know where to look - just a couple days ago I learned about an apparent revolution going on with camera optics via metamaterials for example. Back at university less then a decade ago I attended a talk by one of the leading metamaterial experts back then and the field of study was promissing nice benefits but was far from ready & it was not clear optical metematerials are even possible. Now major camera manufacturers are apparently close to shipping metamaterial camera lenses with before unseen performance at low cost. And that's just one of the examples - we might not be doubling airplane performance records every year as we did in the 1950s but a lot of (progressively harder) cool tech is being introduced every day (5 nm chips, HBM RAM, practical non volatile RAM from Intel, TsV technology making much more stacked chips possible & actual 3D designs in the future, massive expansion of 3D printing everywhere, quick to produce RNA vaccines, ubiqutous joint and even organ replacements, etc.). Not to mention all the IT systems now deployed making all these advances easily accessible to basically anyone on Earth. Also in some cases we hit the "road not taken" territory - with SpaceX Starship for example the Raptor engines are indeed novel and very huge achievement (and the best liquid rocket engine in existence effectively) but the fact that some types of stainless steel being stronger at cryogenic temperatures being was known before yet no one really realized how good match it is for reusable rocket manufacturing.
studius 6y ago
https://news.ycombinator.com/item?id=25477713 https://news.ycombinator.com/item?id=25477713
lend000 6y ago
The part about frequency drift was interesting to me. They covered all the possible explanations I can think of (the source of the signal was orbiting, an object accelerating toward us, or the raw signal itself had increasing frequency). However, I don't see why they need more than one data sample to calculate the rate of acceleration. Also, what benefit might there be to using a chirp signal like this to communicate? The article also does a great job of explaining that it really is quite likely that we will only detect broadcast signals from closer systems. It is simply too expensive and wasteful to broadcast RF out into the abyss. And if there is even just one species a mere million years more advanced than us in the galaxy, they would have had the capability to colonize every system by now, even using chemical based propulsion. Overall, it seems promising, but as with everything in this field, unlikely to be reproducible (which some people will use to dismiss it). Determining the existence of extraterrestrial intelligence is less of a scientific method project than an intelligence gathering one, and many otherwise intelligent science-types struggle to understand that.
- ac29 6y ago
  > Also, what benefit might there be to using a chirp signal like this to communicate? LoRa uses chirp spread spectrum as a method of noise resistance: https://en.wikipedia.org/wiki/Chirp_spread_spectrum https://en.wikipedia.org/wiki/Chirp_spread_spectrum
fathybby 6y ago
What if it's not a civilization.....what if it's a crash ...a. cry for help..what if it's an actual intelligence signal from a downed extraterrestrial and we the monkeys dont know how to interpret the signal.

92 points by weare138 6y ago

"""Unfortunately, this news leaked out before the team had finished their analysis, so we’re left to read tea leaves and parse vague newspaper statements instead of reading their paper on the topic (which does not exist because they’re not done with their analysis!) Someone in the “astronomical community” (we don’t know if they are even a member of the team) leaked the story to the Guardian. Their hand having been forced, the team then gave interviews to Scientific American and NatGeo with some more details, emphasizing that the signal is probably RFI. Now, I’m pretty grumpy about this. SETI has extensive post-detection protocols that were not followed by the leaker, exactly to avoid this sort of situation. Especially since the team was definitely going to announce this, there’s no need for the leak.""" --- It's a bit amusing that after decades of SETI touting their post-detection protocol, they couldn't even keep a sorta-maybe interesting find under wraps for five minutes before someone went running to the media. Where's Jodie Foster when you need her?

zarmin 6y ago
No words. Should've sent a poet.
dvirsky 6y ago
Well, at least we can be certain that there hasn't been any contact made before that's been kept secret for decades.
- KMag 6y ago
  > we can be certain that there hasn't been any contact Conspiracy theories always find a way. Someone can believe that 5G causes COVID (and equally inexplicably, 4G doesn't) can believe this is still part of a cover-up.
  - wyldfire 6y ago
    Those theories are bogus however under the big umbrella of technologies in '5G' are new frequency bands. Those bands may have different absorption characteristics in tissue than previous ones. Buuuuuut they're not viruses, and they're not used for 'spying' any more or less than 4G.
    - rsynnott 6y ago
      Most 5G is at LTE-ish frequencies. The mm-wave stuff is relatively rare and will probably remain so for a while (if not forever; it’s arguably a solution in search of a problem).
      - wyldfire 6y ago
        I know that. And you know that. But it's a kernel or truth that conspiracy theories are able to weave their way about.
        ithkuil 6y ago
        Yeah. Sadly you can always find something somewhere at some point in time that proves the general point of "the government and corporations being assholes". Like when lead poisoning was covered up by corporations and researchers discredited by corrupt "scientists". Yes this happened, and society learned from such incidents and became more resilient. But if you keep getting back at those incidents as "proofs" that everything is corrupt forever, how you're going to solve the problem?
      - DaiPlusPlus 6y ago
        > mmWave I thought the problem was that houses and most buildings outside of North America have solid internal walls which blocks or attenuates mmWave signal strength to such a degree it's practically worthless for anything besides Wi-Gig between consumer appliances within a few feet of each other?
        6y ago
kordlessagain 6y ago
I wonder how many RFIs have been noted to be in the 982Mhz band, especially given we don't know how to transmit at that frequency? > “We don’t know of any natural way to compress electromagnetic energy into a single bin in frequency” such as this one, Siemion says. [1] [1] https://www.scientificamerican.com/article/alien-hunters-discover-mysterious-signal-from-proxima-centauri/ https://www.scientificamerican.com/article/alien-hunters-dis...
- yholio 6y ago
  You might have misread that: we don't know any natural process that would generate a single spectral line at that frequency, but it is very easy to generate artificially by a civilization. Hence, the interest. You can build an oscillator at that frequency with 10$ in parts.
- lovecg 6y ago
  I think that says that we don't know of any naturally occurring sources that would do that, not that we don't know how to generate this signal if we wanted to (which should indeed be trivial).
- VLM 6y ago
  How many unclassified RFI sources around 982 MHZ is the only question we can answer. Its in the L-band for satellites up and down by numerous countries and on the ground there's interesting TACAN and military digital links. Its entirely possible nobody can admit for fifty years that some classified digital data link device had a firmware crash and transmitted an unmodulated carrier for awhile.
  - boznz 6y ago
    Not every country enforces radio spectrum guidelines. I made some 868Mhz lora sensors for a pacific island client in 2016. The customer had a lot of interference from the local TV station and after talking to the island mayor we just changed them to 877Mhz which was quiet
  - adinb 6y ago

imglorp 6y ago

It seems that lunar darkside observatory can't come soon enough: it would be immune to much of this suspected human interference. It would also be relatively easy to set up with existing robotic rover tech, laying long runs of wire on the surface.

Already__Taken 6y ago
would it even be useful just to put and antenna pointing at earth from the moon just to transmit "this is the noise floor of yourself" later add a dark side listener to difference the signals?
giantrobot 6y ago
Lunar observatories are awesome in theory but very face a lot of issues in practice. The first is just lifting their mass. The 64m dish at Parkes observatory weighs in at about 1000 tons [0]. An expendable Falcon Heavy can lift about 26t to GTO which is a bit more than it could put into a TLI. Let's say 22t into TLI. That vehicle needs to actually land on the Moon rather than orbit or crash into it so usable payload to the Lunar surface will be much less than the vehicle/fuel mass. Let's say 14t since it's all unpressurized payload. That's for $150m a pop. You'll need at least 71 of those launches which comes out to a cool $10.6b. The construct-o-bots will need a few more launches so let's round up to $11b. That's all assuming building a huge instrument on the far side of the Moon with robots is all a solved engineering problem. Then there's the Lunar environment. The reason the Moon is covered in Moon dust is because it is constantly bombarded with micrometeoroids. I'm pretty sure the operating manuals for a lot of the sensitive instruments mounted on the Parkes dish say "don't shoot with a gun" which is about the energy equivalent of a lot of micrometeoroids IIRC. One hit to a cryogenically cooled receiver will result in it ceasing to be cryogenically cooled. That tens of billions of dollars for one Parkes equivalent could buy you about 60 FASTs (~$170m) or 30 Arecibos (~$350m).
- imglorp 6y ago
  I was not proposing carrying a dish, instead lay long runs of wires on the surface in whatever pattern you like. But if you want a parabaloid, chose a darkside crater and do the Arecebo thing there. Also, some frequencies are not possible on Earth at all due to ionosphere attenuation.

yodsanklai 6y ago

As much as I love science fiction, I fail to get excited about this type of news. I'm convinced that intelligent life is pervasive in the universe, and also that we're not going to interact with them in any way.

api 6y ago
Why? We haven’t been looking very long or very hard.
- agar 6y ago
  That we have not looked long or hard is why we have not (yet) found a signal. Interacting with an ETI will be much more problematic than finding a signal, given speed of light issues. Or did you misread the OP? He believes ETI is pervasive, which seems a reasonable conclusion to extrapolate as Kepler fills in the F(p) and N(e) terms of the Drake equation.
- jacobwilliamroy 6y ago
  It's a chilling indictment of the human race that all our tools for detecting intelligent life are pointed AWAY from the earth. That's a real red flag, and it would make sense that others would see that and refuse to talk to us. Tangentially, we put almost no effort into interspecies communication. It's asinine to be constantly searching for intelligence when we can't even figure out how to communicate with cetaceans. By now we should have a full functioning networked dolphin-computer interface and dolphin web forums and interspecies instant messenger. But NOOOOOOO, we're all too busy literally shouting at the sky.
  - mwcampbell 6y ago
    Or we could be trying to communicate with parrots (and preventing some species of them from going extinct), as suggested in Ted Chiang's short story "The Great Silence".
    - jacobwilliamroy 6y ago

api 6y ago

I love the rationale for Proxima maybe being the most likely star to be transmitting directly toward us. Maybe it’s a carrier signal for an alien equivalent of a public HAM repeater or a peer to peer mesh net node. It would effectively be a dial tone. Each node broadcasts toward, say, its three nearest neighbors. It sends a carrier that also periodically encodes info about how to use the node and the “IP addresses” of other known participants. Latency would suck though. A complete ping to another “live” station could take hundreds or thousands of years. The vast majority of repeater nodes could be dumb unmanned devices periodically sent out and placed in orbit around other stars. What if our solar system has one and we haven’t noticed it because it’s not that big, is in close solar orbit to easily harness a lot of power, and is only aiming its signals at our three nearest neighbors. Heh.

WJW 6y ago
I like this idea! (though I don't think it's likely) Imagine if the creators of such a system have lifespans of tens to hundreds of millions of years and so could feasibly get somewhere in the galaxy even when travelling at sublight speeds. We'd be so alien to them that they likely wouldn't even think to look for us.
- api 6y ago
  I’m more imagining a collaborative effort much like amateur radio networks. Once you start talking you learn about the net and how to help add more nodes, etc. The node at Centauri might not be from there, but it might be from someone within a few hundred light years who has volunteered to maintain repeaters in their neighborhood. If we came online we would have to generate a call sign (however that is done, instructions repeated along with the carrier) and then start saying hi to nearby HAMs. There would probably be some forum etiquette. Might be a good idea to lurk a while before posting an intro thread. “Oh, look, another n00b asking about how to do net positive fusion power... read the FAQ on the wiki. Nearest mirror is at...”
  - WJW 6y ago
    With our luck the nearest mirror is 500 light years away and by that time we'd have figured it out ourselves. Oh well... :)

jimmcslim 6y ago

The Trisolarans are calling us...

geoah 6y ago
Do you think Ye Wenjie was right to tell them to come over?

baggy_trough 6y ago

982.002 MHz frequency indicates a likely human origin, since aliens or Mother Nature would not be sending an integer number of MHz.

urbandw311er 6y ago
As it states in the article.
Someone 6y ago
If we assume there are zillions and zillions of extraterrestrial intelligences broadcasting radio, chances are at least a few zillion base their unit of time on periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the caesium 133 atom (https://en.wikipedia.org/wiki/Caesium_standard https://en.wikipedia.org/wiki/Caesium_standard) Such civilizations would have a unit of time that’s a rational number of seconds. That would make such clashes possible (but very likely not likely, depending on how likely it is that a civilization uses caesium 133 as the basis for its clocks)
- seppel 6y ago
  > chances are at least a few zillion base their unit of time on periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the caesium 133 atom Of exactly 9192631770 Hz...
  - tatersolid 6y ago
    Do those values depend on the strength of the local gravity well?
VLM 6y ago
Its unmodulated and nobody in the article or comments is willing to consider non-communications situations for both earth and alien sources. Its entirely possible someone out there (us, or ... them) has a nice magnetron (or more exotic tech) pumped main engine or station keeping thruster that uses microwave energy to boost exhaust temp and thus specific impulse. Then given that as propulsion tech, its possible that a boring engineering specification like "make the nozzle two space alien foot lengths in diameter" which is a nice round measurement to a space alien, is in fact 982.blah MHz to our measurements. Certainly no one cares that their terrestrial microwave oven operates at 2.45 GHz, all they know is it pops popcorn. And in a like manner, some microwave boosted propulsion system, either an earth or alien source, might just randomly end up on 982.blah MHz but the number means nothing to anyone, its just what fell out of the thruster design reqs. Say I was building a microwave pumped thruster, I'd make the nozzle less than a tenth wavelength at pump frequency to contain any leakage RF while letting white hot plasma stream out. 982.002 MHz would be 30.5 cm in a vacuum, so figure my engine nozzle diameter would be about 3 cm across for minimal leakage. You're probably not going to get a huge amount of thrust out of something 3 cm across, so its probably a station keeping thruster at most not some main acceleration thing. Besides a couple hours of thrust would imply going very fast if it was a main thruster but some minor course correction / station keeping thing could run a couple hours. So its entirely likely some space vehicle had a pretty substantial failure of a course correction thruster. Another topic no one is willing to discuss, which is a bit weird, is the old fashioned superheterodyne topology works pretty well, so 982.002 MHz is not the frequency of operation, its something in a local oscillator chain of a receiver (or transmitter) that works somewhat above 1 GHz. Another "where are the EEs" comment is 982.002 is possibly not an INTENDED local oscillator output but someone's class B or class AB output stage had a single transistor failure and what was outputing a great low distortion signal at 491.001 is now outputing an icky harmonic signal at 982.002 or similar after the output section failure. Just because the 15th harmonic of the FM sound carrier of an old fashioned analog low-band VHF tv transmitter on USA allocation channel 3 could fall less than 1% off from 982.002 but doesn't prove it is the source and probably is not, the point is we could be observing a failure mode or unintended interference.

biggestlou 6y ago

I'm still looking for intelligent life on this planet!

credit_guy 6y ago

> “If there is intelligent life there, it would almost certainly have spread much more widely across the galaxy. The chances of the only two civilisations in the entire galaxy happening to be neighbours, among 400bn stars, absolutely stretches the bounds of rationality.” This is a fallacy. If there's life all over the galaxy, then we'd be the most likely to detect radio signals first from our closest neighbors. Interstellar distances are, well, astronomical. Proxima Centauri is 1700 times farther from us than Voyager 1 (which was mentioned in the article). Because of the quadratic decay, a Voyager-type source in Proxima Centauri would send to us a signal more than 3 million times weaker. A star that is 10 times farther still will get a dimming of the signal of a factor of 100 on top of this. So, if there are aliens habitating the planets of all the stars around us, probabilistically we'd expect to first detect the signals originating with the closer among them.

m4rtink 6y ago
Thats why I'm thinking megastructure waste heat and weird planetary and stellar orbits (klemperer rosetete[1]) or some periodic high energy events (drives, fireworks, "disputes") will be how we find out about the more interesting advanced neighbors, possibly missing many closer ones who don't influence their environment too much yet.
- Mediterraneo10 6y ago
  Back in the 20th century, I might have said the same thing when I was enamored with Larry Niven’s hard sci-fi. Nowadays, I find it hard to entertain the possibility of civilizations much more advanced than our own: the persistently dismal news and noticeable slowdown in materials-science technological innovation since the turn of the millennium, makes me suspect that races inevitably hit the Great Filter around the point where we are now. After all, hasn’t it been noted that science-fiction is no longer as optimistic about technological progress as it used to be?
  - m4rtink 6y ago
    I think it's not that bad scientific progress wise if you know where to look - just a couple days ago I learned about an apparent revolution going on with camera optics via metamaterials for example. Back at university less then a decade ago I attended a talk by one of the leading metamaterial experts back then and the field of study was promissing nice benefits but was far from ready & it was not clear optical metematerials are even possible. Now major camera manufacturers are apparently close to shipping metamaterial camera lenses with before unseen performance at low cost. And that's just one of the examples - we might not be doubling airplane performance records every year as we did in the 1950s but a lot of (progressively harder) cool tech is being introduced every day (5 nm chips, HBM RAM, practical non volatile RAM from Intel, TsV technology making much more stacked chips possible & actual 3D designs in the future, massive expansion of 3D printing everywhere, quick to produce RNA vaccines, ubiqutous joint and even organ replacements, etc.). Not to mention all the IT systems now deployed making all these advances easily accessible to basically anyone on Earth. Also in some cases we hit the "road not taken" territory - with SpaceX Starship for example the Raptor engines are indeed novel and very huge achievement (and the best liquid rocket engine in existence effectively) but the fact that some types of stainless steel being stronger at cryogenic temperatures being was known before yet no one really realized how good match it is for reusable rocket manufacturing.

studius 6y ago

https://news.ycombinator.com/item?id=25477713 https://news.ycombinator.com/item?id=25477713

lend000 6y ago

The part about frequency drift was interesting to me. They covered all the possible explanations I can think of (the source of the signal was orbiting, an object accelerating toward us, or the raw signal itself had increasing frequency). However, I don't see why they need more than one data sample to calculate the rate of acceleration. Also, what benefit might there be to using a chirp signal like this to communicate? The article also does a great job of explaining that it really is quite likely that we will only detect broadcast signals from closer systems. It is simply too expensive and wasteful to broadcast RF out into the abyss. And if there is even just one species a mere million years more advanced than us in the galaxy, they would have had the capability to colonize every system by now, even using chemical based propulsion. Overall, it seems promising, but as with everything in this field, unlikely to be reproducible (which some people will use to dismiss it). Determining the existence of extraterrestrial intelligence is less of a scientific method project than an intelligence gathering one, and many otherwise intelligent science-types struggle to understand that.

ac29 6y ago
> Also, what benefit might there be to using a chirp signal like this to communicate? LoRa uses chirp spread spectrum as a method of noise resistance: https://en.wikipedia.org/wiki/Chirp_spread_spectrum https://en.wikipedia.org/wiki/Chirp_spread_spectrum

fathybby 6y ago

What if it's not a civilization.....what if it's a crash ...a. cry for help..what if it's an actual intelligence signal from a downed extraterrestrial and we the monkeys dont know how to interpret the signal.