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!)."
Re:I for one... (Score:2, Informative)
It's been 'drudgereported' all day. I saw it this morning on drudge and have not been able to access it. Drudge gets more traffic than slashdot.
Re:And here comes another signal... (Score:5, Informative)
Re:Every time... (Score:4, Informative)
Re:DNA Over Signal (Score:5, Informative)
Re:Every time... (Score:5, Informative)
It is a common misunderstanding that the SETI project is decoding radio signals and trying to listen to some sort of alien language. What SETI is actually doing is looking for radio signals that are not from Earth. They are rather easy to find because as the Earth spins, it will create a very predictable increase and decrease in the frequency of radio waves that are not from Earth (simple doppler effect). Waves produced from the Earth have a near constant frequency because both the sender and receiver and spinning around the Earth at the same time.
An interesting signal is one that is from off-planet. It gets more interesting if the direction of origin is some other galaxy. It gets even more interesting if there is no scientific reason for any object in that galaxy to produce the signal. Finally, with all that checked, someone might try to see if the radio waves are transmitting an actual message - or we can beam our favorite Simpsons episodes right back to source to prove our own intelligence.
Re:Time to go find the dog (Score:5, Informative)
Another article... (Score:3, Informative)
Scotsman.com [scotsman.com].
Mysterious signals from 1000 light years away (Score:5, Informative)
New Scientist [newscientist.com] is reporting that the signal "also happens to be the best candidate yet for a contact by intelligent aliens in the nearly six-year history of the SETI@home project, which uses programs running as screensavers on millions of personal computers worldwide to sift through signals picked up by the Arecibo telescope...*snip*
Re:And here comes another signal... (Score:3, Informative)
Issue #4: Intelligent beings on other planets? (Score:1, Informative)
Coral Cache Ineffective (Score:5, Informative)
Re:Waste of time (Score:5, Informative)
Since the Vulcans are too dumb to figure this stuff out and follow a philosophy we abandoned that hit its peak and quickly declined about two thousand years ago, I'd say that they are too dumb to have actually created warp technology on their own and they must have just stolen the technology from another civilization.
Re:Anyone got a torrent? (Score:5, Informative)
Re:DNA Over Signal (Score:3, Informative)
If the emissions are parallel (as with a parabolic dish), the the only thing which will decrease the power recieved at the other end is absorbtion.
Alternate Stories (Score:3, Informative)
http://www.telegraph.co.uk/news/main.jhtml?xml=/n
Don't be scared (Score:5, Informative)
Re:I for one... (Score:0, Informative)
It's incredible; it was to only browser that was actually usable on my Sharp Zaurus (unlike some pieces of bloatware that eat up 13MB for blank page [mozilla.org].
Re:Would we know a signal if we found it? (Score:2, Informative)
The stuff they're trying to filter out is literally background radiation, typically emitted by stars. This "static" carries no pattern whatsoever; encrypted data would likely be even _more_ complex than simple unencrypted data.
Of course, this all hinges on them being like us enought that what's true on Earth applies elsewhere. That's a rather large assumption, however we cannot avoid it if we're gonna search for ETs. Unless, of course, you'd like to seach for the signals of hyper-intelligent space dolphins.
Re:DNA Over Signal (Score:5, Informative)
The radiation radiates from a point (more or less). As the radiation travels it forms an expanding sphere. The energy from the initial burst of radiation is spread out over the surface area of this sphere.
As the surface area is proportional to the square of the radius, the energy dissipates at a rate of 1/r^2.
For the energy to dissipate at a rate of 1/r^3 it would need to be spread throughout the sphere, as the volumne is proportional to the cube of the radius.
Re:and we wonder where DNA technology is going. (Score:5, Informative)
NeoThermic
Re:Waste of time (Score:5, Informative)
The original series specfically addressed Vulcan "logic" as more of an unemotional state. Their idea is to make a decision based on rational thinking, utilizing the facts at their disposal. The Vulcans/Surak felt they must follow such a course because their powerful emotions were destroying their society.
Furthermore, I'd wager that in cases where one doesn't have enough information to make a "logical" decision, it's usually much wiser to follow one's emotions.
Actually, that was sort of the point of Kirk and Spock's relationship. Spock tempered Kirk's impulses, while Kirk showed Spock that emotions can be a valuable asset when making decisions.
Since the Vulcans are too dumb to figure this stuff out and follow a philosophy we abandoned that hit its peak and quickly declined about two thousand years ago, I'd say that they are too dumb to have actually created warp technology on their own and they must have just stolen the technology from another civilization.
Have you been watching Enterprise? Those aren't Vulcans! They're dumbasses in robes and bowl cuts POSING as Vulcans! I'm willing to bet that they're really aliens created by future guy to slow down human development! The real Vulcans were shang-hied by future guy before they met Cochrane! Or maybe Enterprise just sucks. Hmm...
===/GEEK ALERT===
Putting the technobabble aside for a moment, the Vulcans were a plot device that Roddenbery used to explore the human condition. It's quite common in writing to take a human trait to an extreme or remove it so as to use the contrast to better explore the attribute. In the case of Star Trek, the "emotional" vs. "unemotional" contrast allowed the strengths and weaknesses of each approach to become obvious.
Re:DNA Over Signal (Score:5, Informative)
This isn't a true statement depending on what exactly you mean...
For one the range of the electromagnetic force is infinite (see this for more information [gsu.edu]).
Second the inverse square law comes from the fact that the area of the shell of radiation coming off of a point source (star for example) increases to the square of the radius from the source (basic geometry). Yet the amount of energy (number of photons in the case of electromagnetic radiation) that is in that shell of radiation is constant so the density of those photons reduces by the inverse of the square of the distance (See this for a graphical explination. [gsu.edu])
So if you look at a given photon traveling through space its "signal" will not weaken with the square of the distance, if it did this universe would be a dark dark place (also it would break the concept of quanta).
Also if you have photons traveling parallel to each other then the inverse square law doesn't apply because you have not radius to begin with.
Now it is hard to get fully parallel photons but you can get close (lasers, maser, etc.) and the closer you get the greater the radius of the theoretical point source for the signal. The greater the radius of the point source the father the signal can propagate before the exponential effects of the inverse square law begins to take hold.
So yes it is likely that the inverse square law applies to signals such as these but the point source radius to use in the calculation can be relatively huge if you take steps to focus the signal (attempt to have the photons travel in a parallel beam).
Re:Quantum entanglement (Score:2, Informative)
A (very slightly) more precise way of stating this is that quantities within the theory seem to be transmitted instantaneously, but that these quantities are not available for use... It may sound suspicious, but it's true (where of course, very particular things are meant by the rather vague words I have chosen).
In cryptography, the information is sent using entanglement of particles, but this does not allow instantaneous communication; this is a common misconception. The breakthrough is not instantaneous communication, but rather in provably secure communication (again, in a quite particular sense). A doubling of bandwidth might also be possible, but my memory is failing me on the details of quantum teleportation/cryptography.
Re:DNA Over Signal (Score:5, Informative)
Lasers aren't actually parallel. They are diffraction limited. The smaller the collimation the more quickly they diverge. A big diameter laser can have a lower divergence, but then the energy density is also lower. And still, over the distances we're talking about it would still be a huge spot size.
Re:1470 Hydrogen (Score:2, Informative)
Re:DNA Over Signal (Score:4, Informative)
Correct! I also want to point that even though "absorption" may sound like nothing (especially in space), it is actually an exponential process.
For big distances, the exp(-x) process will dominate the 1/(r^2) process, i.e. absorption will dominate beam widening.
You have a rather clear view in space, though.
Re:DNA Over Signal (Score:3, Informative)
Thanks guys.... (Score:5, Informative)
But it was you guys all along! [StrongBad tear]
Seriously. To your credit, I first found out about SETI@Home on Slashdot and ran it for years on spare computers.
Now I have made SHGb02+14a my beeyotch.
Then you guys Slashdotted the article before my mom could see it.
Re:Thanks guys.... (Score:5, Informative)
One of my computers found that signal. (magenbrot did too, but I dont know if he/she is aware of it yet)
I have the feeling it was my wife's computer, as it was doing the most crunching at the time of the original hit. (She uses it, I built it.)
Re:Quantum entanglement (Score:4, Informative)
Quantum cryptography lets you recognize when you have the same bit (sent via the phase of an entangled photon) that the sender has. You don't get to pick what the bit is; you can just tell when it's the same. So it lets you have a one time pad that you didn't have to establish ahead of time. The pad is the bits sent via the photons. Then the sender sends his message XORed with the one time pad (turning it into random noise for anyone who doesn't have the pad), and the receiver XORs the message with the one time pad to get the original message.
The reason this is so secure is firstly that the message is indistinguishable from noise if you don't have the pad and secondly that it's not physically possible to intercept the pad without letting the real message recipient know. This second part is because detecting the phase of the photon eliminates the wave nature of the photon.
Re:DNA Over Signal (Score:3, Informative)
Mod parent down. (Score:4, Informative)
The public lynching will be held at 12 noon tomorrow. Or something.
Re:Every time... (Score:2, Informative)
Re:My God, it's full of primes! Seriously! (Score:2, Informative)
Re:Forget the math for a second (Score:2, Informative)
Re:Forget the math for a second (Score:3, Informative)
What prevents someone from hacking into a Seti network packet and make it seem like the signal meant something?!
Well, IANASetiExpert, but I'll take a stab at this. One, Seti does basic validity checks on the data blocks they receive back.. I don't know the full extent of the checks but I know they're meant to reject obviously fake work units, as well as work units from modified clients. Second reason is Seti sends each work unit out multiple times.. So if they get the unit back with 4 results saying one thing, and one result that's "interesting", they'll probably throw out the anomaly and stick with the 4 consistent results. Lastly, even if you fake an "interesting" work unit and they accept it, no one goes running around screaming "we found ET!". They simply flag the coordinates in the work unit and train the receiver in that direction again when they have time to take a closer look.
Re:Every time... (Score:4, Informative)
It turns out that oxygen is produced in great quantity both due to the CNO fusion cycle in massive stars, and nucleosynthesis during supernova explosions. So, I'd expect oxygen-dominated chemistry in most star systems.
Silicon is also a favoured nucleosynthesis product, which is why silicate rocks are so common.
Re:DNA Over Signal (Score:4, Informative)
Whatever the change in cross sectional area over distance X, there will be 4 times the change in area at distance 2X, 9 times the change at 3X, and so on.
This is what the inverse square relationship means.
MSNBC's take (Score:3, Informative)
Alan Boyle of MSNBC [msn.com] has this take:
Re:Waste of time (Score:4, Informative)
You say this as a math major who needs to do one of a) get his money back, b) pay more attention, or c) transfer to a better school.
Ok, that was harsh. You won't find a better school anywhere, so I guess it's not your fault.
Logic isn't a field of study that began in mathematics - it's a field of philosophy, specifically in epistemology (the study of how we come to know things). Actual logic is the doctrine that our ideas, to be correct, must conform to reality. That is, ideas must be derived from reality primarily by observation and by processes which are themselves derived from the actual relationships amongst actual things in the physical world (again, observation). Logic most specifically does not start with axioms from which all other knowledge is then derived.
Yeah, that philosophy was abandoned about two thousand years ago - and look what replaced it: the Dark Ages. If it hadn't been for Thomas Aquinas re-introducing that philosophy through the works of Aristotle, we might never have recovered from abandoning those oh-so-declined ideas.
Thats not the Voyager plaque.. (Score:4, Informative)
That link in the header is for the Pioneer plaque, not the Voyager golden record..
http://voyager.jpl.nasa.gov/spacecraft/goldenrec.
Re:Hz = (Score:4, Informative)
Doesn't Hz stand for frequency, 1 per second? How can this be 1.5 'events' per second per second?
This means a change in frequency. Say, the frequency starts at 100 Hz, and after 10 seconds it's 115 Hz. It's changed by 1.5 Hz per second.
Same with acceleration, it's a change in velocity so it's measured in meters per second per second.