BLC1: A candidate signal around Proxima
sites.psu.edu
sites.psu.edu
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."""
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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?
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.
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?
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?
One edge-case application _might_ be stadiums, large train stations etc. But in practice these days these can often be covered quite adequately with small LTE nodes. And that will improve with 5G, even without mmWave.
> “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-dis...
You can build an oscillator at that frequency with 10$ in parts.
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.
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
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.
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.
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...”
Edit: here's a nice diagram https://en.wikipedia.org/wiki/File:Roundtriptimes.png
So you can go on long interstellar voyage and only age for a coulpe weeks or moths where you are actually active, the rest being in hibernation or time going much much slower for you due to time dilatation. There are even some scientists that will spend just a couple days per misdion awake to study an interesting phenomenon, being in hibernation for the rest of the journey!
Of course if you have any friends or family somewhere they will be decades older or even dead by the time you get back.
On the other hand if you have friends in the spaceflight community it is much less of a problem as you will be meeting the same people over your travels on various stations or missions as decades or even centuries go by.
For that reason a lot of the space community is joung people who migh want to settle down once they are oldet (and never see their spacefaring friends agai) and centuries old academics who are having the time of their lives, studying the wonders of the universe every single day (from their perspective).
Zone 7: Sol system (off Earth)
Zone 8: Centauri System.
Nearby civilizations will send interstaller probes to the closest stars first. Because that's what everybody would do.
And their scientists are more likely to get money to communicate with probes than speculative aliens.
And as an interstaller probe gets closer to the target system, the amounts of power needed to communicate with it is enormous.
Altogether this means first contact is likely to be a radio or laser signal meant for an interstellar probe that's headed towards us.
All theory crafting though lol. But it would jive 100% with funding realities on our planet. I think for this reason alone we should listen to our ~20 closest neighbors extra well.
The sad downside is that if they're the closest star to us, we're also likely the closest star to them. That means very few civilizations would send a probe to us first :'(
later add a dark side listener to difference the signals?
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).
Also, some frequencies are not possible on Earth at all due to ionosphere attenuation.
Wire antennas for a radio telescope are not a great solution. A giant array of antennas (still a lot of mass to lift) could have decent angular resolution but not great seeing power. The seeing power of a telescope is a function of the totally collector surface area. A big dish literally reflects photons that hit any part of the surface. A wire antenna with no reflector has a teeny tiny surface area.
For an antenna array you'd still need steering sturdy mounts, steering systems, and power for those steering systems. Just using big wires means you can't really steer the focus and has far less gain than an array and way less than a system using reflectors. TANSTAAFL.
But GP wasn't talking about any dish. Just wires.
Most likely a more mundane setup might be a better first project + due to 1/6 g and no storms to withstand the antennas could likely be much lighter.
Every gram of fuel is one less gram of payload. So a Starship either needs to carry all of its fuel needed for Lunar take-off and TEI (significantly reducing payload) or refuel on site. Since there's no LOX and Methane deposits on the Moon every Starship Moon landing would need both sent to the Moon ahead of it.
Even if you want to assume you can find a bunch of water ice under the regolith you then need to send up a water cracking factory, compressors, and literally tons of solar panels. Then you still don't have any methane. So even if you just have to send methane you've had to build a huge amount of infrastructure out of technology that doesn't exist just to reuse Starships. If you don't reuse Starships you don't get much dollar savings over using Falcons.
Starship is designed to use aerobreaking for landing. This is something that's viable on Earth and Mars but useless on the Moon. So any Starship landing on the Moon needs fuel to de-orbit and land, with aerobreaking only the terminal phase of the landing needs fuel.
Starship's economics only really work if there's fuel available in LEO, its destination, and its destination has an atmosphere for aerobraking. If those things aren't true it needs to carry all of the fuel needed for its mission from Earth's surface which significantly reduces its payload.
Doing shit in space is hard.
Building something like a radio telescope on the Moon is not impossible and doesn't require any unobtanium. It is however pretty far out in terms practicality. Just about zero of the engineering capability required has been demonstrated.
Even if my estimates for a Lunar radio telescope were off by an order of magnitude and it would only cost a billion dollars, that's still several FASTs or Arecibos you could build on Earth. The Lunar environment is harsh. Micrometeorites, cosmic rays, and solar flares would wreak havoc on sensitive components of a telescope (radio or otherwise). They're much more of a hazard on the Moon than on Earth because the atmosphere and magnetic field protect the surface. A repair or replacement of a component on a terrestrial instrument might be thousands or millions of dollars. For a Lunar instrument would be at least in the millions.
There's a very weird meme going around that because SpaceX exists doing things in space is suddenly simple and cheap. Space is hard. SpaceX et al are making it less expensive but not by huge divisors. A Falcon 9 reusable is only a little cheaper than a Proton-M for similar capability. It's cheaper than ULA rockets by about half. It's a feat for sure but it's not like LEO is suddenly as affordable as air freight.
https://www.nasa.gov/directorates/spacetech/niac/2020_Phase_...
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.
After all, hasn’t it been noted that science-fiction is no longer as optimistic about technological progress as it used to be?
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.
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.
LoRa uses chirp spread spectrum as a method of noise resistance: https://en.wikipedia.org/wiki/Chirp_spread_spectrum
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)
Of exactly 9192631770 Hz...
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.
But, as the article puts it, "suspiciously close". Except, I guess you'd accept .003 as close also. And, from the other side, you have .999, .998 etc. If you accept the range .995 to .005 as "close", that's already 11 values, so around 1 in 90 chance of hitting it at random.
Except, there might be other "suspicious" values. Like, .100, .200 etc. That gives us another 9. And then you could have things like .111, .222 etc.
If you accept around 50 different suspicious values of some sort then there's a 1 in 20 chance of hitting one at random. That doesn't seem so suspicious to me.
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.
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.
It's common for birds to learn a few (human) words in context of an action (names / contact calls, food, waste disposal, etc), and it's common for someone who lives with birds to learn what their different types of calls generally mean (contact calls, distress calls, etc). Interestingly, parrots do seem to exhibit many emotions found in humans (anger, fear, happiness, sadness, love, jealousy, etc -- I suspect these are common among social animals).
If you think of language as a way to externalize our internal state then a prerequisite to understanding and communication is the ability to translate that state into something the recipient can contextualize. The difficulty of communication then increases with the difference between the party's respective inner states.
For human-human interactions it's possible to start from nothing and learn to communicate effectively in a couple of years. For human-parrot interactions, we can literally chatter to each other all day for 50 years and we'll never develop anything more than a cursory grasp of each other's languages.
On a more cynical note, were we able to properly communicate with animals it would force us to confront some uncomfortable things about our food supply chains and treatment of the planet in general. Parties that benefit from the status quo aren't really incentived to change that.
We are like an Uncontacted Tribe with technology. Even if we managed to decode a signal (not really feasible as many encoding schemes utilize quite arbitrary formulas and mapping tables), we would still not understand the language. Humans are pretty bad at figuring out languages without some sort of rosetta stone. Even if we understood their language, we might not be able to comprehend it, or comprehend it in fallacious ways, because of missing context. To compare, do our dramas, thrillers, TV shows, horror movies, porn (unfortunately often including children), and Youtube videos really portray an accurate picture of Human life and culture? We are ourselves quite bad at understanding other human cultures, past and present, and often rely on stereotypes...
That's a big claim without any evidence at all.
We may share a universe teeming with intelligent life, but if that life takes 10000 years to metabolise a meal, and a decade to say "Good morning", there's very little chance we shall communicate meaningfully.