SETI Finds Interesting Signal 816
Several readers sent in notes about an interesting signal discovered by SETI. No real evidence of Someone Out There, but not fully explainable either. Another reader submits a blurb suggesting that aliens should send spacemail, not signals: "Rutgers electrical engineering professor, Christopher Rose, has an article on Nature magazine's cover today describing the most efficient way for our civilization to be discovered by aliens. On this question of better to 'write or radiate', his conclusions: better not to send radio transmission, when physical media like DNA on an asteroid can declare a terrestrial presence. Similar to what motivated Voyager scientists to attach a plaque for the outbound trip. Rose has some great information payload sizes as examples (like the entire information equivalent for our global genome fitting on a 100 pound laptop!)."
Every time... (Score:5, Interesting)
Re:DNA Over Signal (Score:5, Interesting)
Is it just me... (Score:3, Interesting)
I didn't read any of the articles yet because they all appear to be slashdotted. Nice going everyone.
One question (Score:2, Interesting)
As I understand, a spread spectrum signal won't appear as a strong peak in fourier space (that's what seti is essentially looking for).
Any thoughts?
Would we know a signal if we found it? (Score:3, Interesting)
Perhaps I am naive, but I think about the things human beings could always see, but couldn't understand until their knowledge progressed past a certain point.
Anyone got a torrent? (Score:3, Interesting)
They should made the data available (Score:5, Interesting)
Re:One question (Score:5, Interesting)
Basically, I've heard it called the window and door problem - we have a window of 50-100 years (I forget whose estimate) when a civilization is accidentally radiating to find them, and then we have to wait for them to open the door by transmitting intentional beacons.
Re:Every time... (Score:3, Interesting)
Also environmental conditions favor body styles. The 'wolf' body form and ecological role has evolved over and over in the placental and marsupial lines.
Intelligence also favors omnivores that can rapidly move into new areas and are not specialized to any food and can readily adapt to the environment. As soon as humans developed tool use and could make clothing and specialized weapons we could out 'evolve' any other animal because we no longer needed natural selection to factor in to changes.
So we're likely to find any civilization is going to be derived from symmetrical linier body plan. Number of paired manipulating appendages would be up in the air. As we as sensory, and reproductive organ placements.
Re:Mysterious signals from 1000 light years away (Score:3, Interesting)
Short version of above: correcting for doppler shift when the viewer's direction is unknown is impossible -- it makes much more sense to NOT correct at all.
Re:DNA Over Signal (Score:2, Interesting)
It would give new meaning to S...O...S...
good idea why?? (Score:3, Interesting)
If any "advanced" alien culture finds us I for one am hoping that we have nothing they want.
stendec@gmail.com
Re:Every time... (Score:5, Interesting)
Not necessarily. On a somewhat cooler world than ours with 4-5% flourine in the atmosphere, water would be immediately broken down into oxygen and hydroflouric acid, which is liquid in the -83 to 19.4 C range.
This works because "plants" could function by photosynthesis with HF in place of water and carbon tetraflouride in place of carbon dioxide to produce H-C-F chain compounds and liberate free flourine, with nickel as the catalyst in place of the magnesium in chlorophyll. We'd have to postulate higher UV energy levels as well to provide enough decomposition energy, but that goes along with a thinner atmosphere and lower temperatures without much of a stretch.
"Animal" soft tissues in this scenario would be about the same as the plants, but hard tissues would be produced by the reaction
{ H-C-F } + F2 -> { F-C-F } + HF
resulting in a teflon boned and shelled organism, probably one muther-tough sonofabitch. His main energy reaction would be
{ H-C-F } + F2 -> CF4 + HF
with a blood catalyst metal of titanium, which would result in colorless arterial blood and violet veinous, as the titanium flips back and forth between tri- and tetra-valent states. So he'd probably be a good deal more energetic than us 02-running organisms as well.
Given what we know about vulcanism on the outer moons and so forth, I wouldn't be surprised to find that a scenario along these lines is rather more probable around the universe than the local one we're familiar with.
Their technology would be rather different than ours too, since no terrestial style organic matter is possible, and there wouldn't be much around except flourides; no oxides, sulfides, silicates, or chlorides. All metallurgy would have to be electrical. Oh, and they probably wouldn't be good mountain climbers either, since flourides are structurally weak; nothing tough like granite to make mountains out of. So technological progress seems a trifle unlikely. But *shrug* they'd probably think that about Earth, too...
Re:Power supply (Score:2, Interesting)
the probe could be programmed to start transmitting whenever it got power to its solar cells and keep going until the power's gone. At least it would be talking whenever it's near another star
Re:DNA Over Signal (Score:1, Interesting)
Between two electrons, A and B, there exists a repulsive force that reduces in strength by the 1/r^2 ratio we all know and love.
The repulsive force is described as an exchange of a virtual photon between the two. The virtual photon has a mass/engery associated with it, such that it cannot be more than A+B's rest mass/energy (violation of law of conservation). The closer the particles, the closer the virtual photon's rest/mass energy is to A+B, and the stronger the force is. The further away, the weaker it is.
The problem is that energy is quantized. At some distance r, the rest mass/energy of the virtual photon is less than plank mass. Since plank mass is the smallest possible mass, anything less is zero. Zero = it doesn't exist!
(Note I say mass/energy in terms of the massless photon to note that it still has energy due to E=mc2 yada yada)
IIRC the calculated range of EM between two isolated electrons is roughly the size of the milkyway, so it's not as big as you'd think!
This also has only to do with the EM component of a particle. A photon itself has infinite range. Two particles however cannot "feel" each other over infinite range as it would require a virtual particle with less energy than plank mass/energy.
Interesting, But Probably Not ET (Score:3, Interesting)
Disclaimer: I am not a SETI scientist, but I play one on my home computer [berkeley.edu].
Named SHGb02+14a, the possible alien communication has a frequency of about 1420 megahertz - one of the main frequencies at which hydrogen, the most common element in the universe, readily absorbs and emits energy.
If the signal was some multiple of a prominent hydrogen line, I'd be more inclined to think it's ET. The hydrogen line would be a universally understood reference frequency, and a frequency that is a multiple of that frequency by a factor of 2, 3 or pi would be a frequency that wouldn't have a lot of naturally occurring interference. When the signal is the prominent hydrogen emission line, it seems a lot more likely that this is a previously unknown natural phenomenon. Some hydrogen out there is being excited by some form of naturally occurring energy. That's still not a bad discovery, and is a good example of the surrendipity that's always been at work in science, and it shows that SETI is doing *real* science, despite what SETI's detractors might argue.
The unexplained signal appears to be emanating from a point between the constellations of Pisces and Aries, where there is no obvious star or planetary system within 1,000 light years, and the transmission is also very faint.
That seems a bit suspicious too. It would require an enormous amount of power to broadcast a signal we could detect over that large distance. Wishing doesn't make these things true, but I'd certainly prefer a signal from a closer neighbor, so we could have a meaningful conversation.
So far, the telescope has managed to pick up the signal for only about a minute in total, which is not sufficient for astronomers to analyse it fully.
That's the problem with a fixed dish. It points where it points, and it moves as the Earth rotates. SETI gets "leftover" time on Arecibo, making it difficult to do the research they'd like to do. That should change soon when SETI has access to their new large array of dishes forming an interferometer that they can point where they want, and dwell on an area for a much longer period of time. Paul Allen may have been instrumental in creating the evil Microsoft empire (see how I worked in the mandatory /. anti-MS bias?), but he's provided adequate contrition for that sin by funding Scaled Composite's X-Prize hardware and the SETI interferometer. What a dude.
Other questions arise over the signal's frequency, which oscillates by between eight and 37 hertz a second. Paul Horowitz, a Harvard University astronomer who looks for alien signals using optical telescopes, believes that the drift in the signal makes it "fishy".
OK. He's an optical guy. But he's never heard of Frequency Modulation (FM radio)?
Assuming it's a natural phenomenon, this might be Doppler shift? I don't know how quickly the frequency drifts, but large planets have been observed close to stars with orbital periods of a couple of days. With weird objects like black holes and neutron stars, which definitely have the power to produce signals we could detect from that far away, who knows what type of weird celestial mechanics might be involved?
This unexplained phenomenon has now attracted the attention of radio astronomers. It'll get the instrument time required to collect a lot more data, and we'll probably learn what's causing this signal fairly soon. Man, ya' gotta' love science.
a text message to the stars (Score:2, Interesting)
On the other hand without a whole library to sift though who is going to make sure the picture is fair and balanced... lets touch that when they are ready to visit.
Hope this picture helps a bit
Phil
Re:DNA Over Signal (Score:4, Interesting)
Excellent point, but not necessarily true. Sure, you'd need a long integration time, but that doesn't mean that the code rate would have to be slow. If the signal is periodic (and it'll be hard to be noticed unless it is), you or the aliens can integrate bits from different cycles. That's assuming that the receiver knows the period, but with enough compute power, they can try all possible periods.
The Arecibo bit rate is 10 per second -- much faster than most deep space star exposures, but decipherable with the above method.
Allow me to conjecture wildly for a moment... (Score:2, Interesting)
This is really, really exciting. I can think of several possible reasons for the anomalies found in the signal thus far. I'm also aware I'm twisting the facts to fit a theory.
The signal originates where there is "no known star system". Of course. You (advanced alien culture) place the radio source outside your own system, for several reasons - so that the signal won't be confused with a natural source (pulsar, etc); so it won't interfere with radio reception on your own planet; and (for those of an especially paranoid bent) so that if anyone does try to physically investigate the source of the signal, they're not lead directly to your home planet. Instead, set a "tripwire" up on the device - if it's disturbed, send a signal back to the home planet (a scenario explored in Clarke's short story "The Sentinel", which became the basis for "2001").
The frequency is wavering? Of course! Set the signal to repeat over as broad a frequency range as possible, to attract as much attention as possible - not everyone will be looking at the "waterhole".
Did I mention I was excited?
Re:good idea why?? (Score:3, Interesting)
If we do find an advanced alien civilization then they may merely decide that we are a violent race and decide to exterminate us for their own safety on the other hand if we were to find an alien race that was technologically inferior to us then no doubt some country or some people would either try to destroy them or abuse them because they could.
Consider how many wars are ongoing right here on Earth right now. There is no reason why we would necessarily have peaceful relations with aliens.
NOPE!! Trumped up by a reporter (Score:2, Interesting)
Mr.(Dr.?)Shostak said the first he heard of this was within the last couple days, and when he contacted the SETI@Home folks(which is NOT part of the SETI Institute, but they certainly have a working relationship) to find out what was going on, they also weren't really sure what the hoopla was about.
Apparently the reporter didn't fully understand the intricacies of the signal hunt, if you will, and got WOWed by a marginal-to-non wow.
Oh well. But if Coast to Coast isn't buying it
sorry to burst the bubble. i'm disappointed, too.
8#
Re:Every time... (Score:4, Interesting)
Re:Better to be weary (Score:2, Interesting)
Of course, if they don't have FTL travel, they may just be patient enough to wait out a little radiation.
Re:Hope to $DIETY it's the extraterrestrials... (Score:3, Interesting)
Re:DNA Over Signal (Score:5, Interesting)
They get completely overpowered by the huge great big solar radio emitter, so that by the time they reach another starsystem, all thats resolvable is the signal from our sun itself.
This actually turns out not to be the case, for a couple of reasons. First, Earth outshines the sun on several radio bands - the sun's dumping most of its energy as visible light, and while electrical effects in its atmosphere are noisy, they don't cover the entire radio spectrum. Second, we could launch solar-orbit radio telescope arrays _now_ that would have enough angular resolution to pick out individual thunderstorms on the superjovian planets we've detected nearby. Resolving a beacon from a star spatially, for any star system near enough to matter, is do-able (though we aren't going to do it ourselves until we decide a space-based radio telescope array is worth the money).
I also question the parent post's assertations that radio signals are degraded to unintelligability. We can pick up millisecond pulsars just fine, meaning we could at the very least broadcast a beacon with data modulated at kHz rates. My understanding is that there are relatively clean frequency windows in the interstellar medium that would let us transmit intelligeably at far higher bandwidth.
Re:Some things are universal, not cultural (Score:3, Interesting)
Please spell out how! That's all I'm asking.
The "can't possibly be biased" element from my original post was the frequency of the light being transmitted, not the use of EM in the first place. Hydrogen emission lines are fundamental constants of nature (at least in our neck of the woods; ObCaveats about very, very distant parts of the universe possibly having different values for these constants). Choosing a blatant derivative of one would be an unambiguous way of saying "look, I'm intelligent!" that is not tainted by human biases (except in the definition of "intelligence").
The argument for EM is that we seem to understand virtually all of the observable universe now, unlike your proposed witchcraft-using primitives, and EM looks like the _only_ choice for long-distance communication. The only possible objection is that we can't be sure that we understand the universe well enough to label alternate communications modes "unlikely".
I consider it likely that we understand the universe well enough to do this, as the relevant bits of physical theory have been around arguably even since Newton's day, and have stood despite very aggressive challenging (new models are best viewed as extending, not overturning, old, as they tend to reduce to the old models in the old models' domains of applicability). Your opinion may vary (and apparently does).
Why not mix ? Explains seti signal .. (Score:2, Interesting)
You wouldn't need to correct trajectory much, since you'd just be aiming at getting away from your earth and you would reduce the transmission power requirements.
Might explain why the signal found by S.E.T.I. is coming from nowhere. You'd have to check the parallax shift to determine the actual signal distance.
I'd have no explanation for the shift in frequency though, if it came from a spacecraft.
Maybe the data is in the change of frequency, not intensity, or frequency is intentionally shifted to make the signal noticably by planets that rotate themselves.
Re:Some things are universal, not cultural (Score:3, Interesting)
The progress of science has gradually reduced the number of entities/objects/forces required to explain all existence. If you don't think electromagnetism is appropriate, then there are exactly two other choices: gravity or "strong" (atomic cohesion bonds, aka physical matter).
Of the 3 fundamental forces, EM seems the best way to communicate.
So, how can I tell if what I've picked is subject to bias or not? Please spell out how! That's all I'm asking.
How do you know that you're not completely insane, and everything you see around you is a delusion?
Questions of that form cannot be answered, but it doesn't matter. If you're right you're right, and if you're wrong, you have no way of ever knowing. If our knowledge of physics is so far off as to be missing something so important it could be used for communication (quantum telepathy waves?), then there's no hope for us.
Re:Waste of time (Score:2, Interesting)
Re:Some things are universal, not cultural (Score:3, Interesting)
Indeed it is - and doesn't it apply here? If EM signals take hundreds of years to reach us from nearby stars, don't you think aliens wouldn't even bother trying to send them out, realising how pointless a means of interstellar communications these signals are? They're likely to be either working on a more appropriate/speedy technology for communications or have already developed it, and we don't have a clue how to pick it up.
Re:DNA Over Signal (Score:3, Interesting)
On the other hand, you can also focus your radio transmission. The inverse square law only applies if you are emitting in all directions. If you send a relatively well collimated beam out from Aricebo, you're going to have a very well-behaved signal that you can detect a long way off. Indeed, this was done decades ago.
The chief advantage of throwing rocks is that it requires no maintenance at this end. If you want to use a radio beacon, then you have to maintain it for as long as you want to transmit, and you're limited quite a bit in terms of the number of targets you can point to with each dish. Meanwhile, radio signals will get to your target a lot faster (whether this is a good thing or not is open to discussion) and are probably easier to detect than a rock.
Figures (Score:3, Interesting)
I got tired of the information void that they were presenting on server/app status when rolling out BOINC. They got numerous offers from a range of supportive folks from students to users to faculty at OTHER colleges to keep the web page up to date and ignored them.
The newsgroups that allegedly supported the project looked like text book examples of bad usenet w/the flaming and "screw you, you're a volunteer" msgs. The user/support forums on the website were seemingly user run w/little input from the project as well.
After losing my old my-deja email and credit for those units and all this warm fuzzy support, I decided to take my CPU cycles elsewhere.
(and bask in the glory of being ignored there too no doubt)
Re:Some things are universal, not cultural (Score:3, Interesting)
Kind of a self-limiting process on who who want to communicate with on what level, as well.
Re:DNA Over Signal (Score:3, Interesting)
Well, why not use a focused EM signal pointed toward the 100 nearest stars? Exactly the same argument applies. If you focus it tightly enough you will lose very little power.
Your rocks, by the way, will either make it or not make it (perhaps because they crash into something else orbiting the destination star before they're noticed). Admittedly, the star's gravity means you have a large target to aim for.