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Space Science

Is There Anybody Out There? 188

Posted by michael
from the E.T.-phone-home dept.
DrZoom writes "The Astronomy Picture of the Day for Jan 9, 2001 is an image sent into space by the Cosmic Call project. This is yet another interesting picture from APOD." Try to figure it out without reading the solution.
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Is There Anybody Out There?

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  • by Anonymous Coward
    imagine that. a series of primes. i could've guessed without having to actually look at the damn picture.
  • by Anonymous Coward
    They really should have made his wang bigger.

    It would have raised our status in the intergalactic empire.
  • by Anonymous Coward
    The two maps that you call pangea + partially split continents are just 2 halves of one map - a normal equiarea projection of our earth's surface *today* . Yes, Asia and africa really are THAT big. Don't forget, to project the surface of a sphere onto a flat plane, you have to distort it. The system these people used is in fact "fairer" than most maps you'll have seen - giving equal weighting to the land area of every continent. Look at a globe some time (the only really fair way to represent the earth's surface), and imagine how their map would be wrapped around it - it'd be a better fit than the normal rectangular projection maps.
  • by Anonymous Coward
    Is it just me that thinks sending this message out was irresponsible?

    This message reveals quite a bit of information about us. A receiver will know not only details about our solar system, but even fundamental details of how we are constructed (DNA, etc.). The message also reveals quite a bit about the resources of our solar system.

    If this message is received by smart aliens intent on conquering systems then from this info they given that knowledge they should be able to build a weapon to wipe us off the face of this planet.

    Whilst there are many people that theorise that aliens capably of interstellar travel will be friendly there are no guarantees. By sending this message we may have doomed us all to death, or enslavement.
  • by Anonymous Coward
    With "our" symbols, we would either have to lenghten the message significantly or raise the resolution of each of the pages.

    sigh. did you even attempt to decipher the message? there's nothing in there that cannot be said (with even fewer pixels) using ordinary "glyphs".

    the real (non-slashdot) explanation can be found in the cosmic call press release:

    The message has been built to minimize the loss of information due to noise introduced into the signal during its interstellar flight. To minimize the risk of confusion, a set of characters was created which are fairly different from each other. Redundant information is included to allow cross-checking of the message

  • 5,010,240,000 Hz

    As detailed in page 21 of the message:
  • And wouldn't _that_ be an interesting message to get as a reply from an alien civilisation :)
  • Actually there is a one pixel wide frame around every page, so it would not be very difficult to discover it.
  • by shogun (657)
    I am somewhat forced to agree, considering the difficulty finding intelligent life on just this planet...
  • This is nice in some ways, but it seems pretty bizarre to go to all this effort to teach them decimal and kilograms. Why not make things more universal by using binary exclusively for numbers? Why not use a more "universal" measure of weight, like the weight of a proton? Why go to the effort of teaching them meters, seconds, and kilograms?

    Sheesh, they even use superscript notation for exponents! Just explain about brackets, and use "^"!
  • what they didn't show you is the last page of the series, that shows how to decode TV signals so that they can watch leave it to beaver. In contact they sent plans on how to make a space ship... I'm pretty sure we would send plans on how to make a TV.
  • It wasn't too difficult to decode, but I still
    have one question: how did they decide on those
    sybols to represent digits? Why not something
    simpler, maybe 7-segment LED-style numerals, for example?

  • I'm not convinced by your argument. Each digit symbol in the message is 5x7 pixels. You can easily represent our digit symbols in that resolution.

  • Looking at the thing, I assume the white is 0 and black 1 and I can only wonder why they didn't do it the other way around. white 1, black 0, after all, there is more white on this page than back, and what is more noticeable? an absence of signal or a signal?

    Ahh but the whole message is a signal, 1 or 0. If I recall the transmission is made so that a 0 is one frequency and a 1 another (FM). The carrier is there no matter what is transmitted so it really makes no difference whether it is mostly 1s or mostly 0s.

  • I knew I should have put a smiley on it for the humor impaired. Sheesh.
  • I think that's about right, in a galactic sense. Is this message anything more than posting a "Hey, lookit us! We's smart!" to all the advanced races out there? It's just like those first posters trying to get attention. Just like them, I say. We as a race will say any stupid thing in order to get attention.

    Do you really think any race capable of receiving this doesn't already know what a prime number is? They'll just moderate us to -1, and if we're lucky someone will tell us, "Duh! Go away you damn trolls, we know that already."

  • And wouldn't _that_ be an interesting message to get as a reply from an alien civilisation :)

    I say bring it on. We've had 21 years of practice at repelling Space Invaders, and that's with only one gun. ;)
  • Presumably, if we're smart enough to throw squiggles at them and they're smart enough to read them, it should work both ways. Especially considering the time it'll take their squiggles to get back.
  • Funny -- my first thought when I saw it was "Space Invaders!" Kind of appropriate...


  • Does anyone know why they are the way they are? I guess one of he design considerations was to fill out the cell more than our regular symbols so that it would be clearer whether a "white" pixel was part of a symbol or not. This makes spacing easier to comprehend. Any other thoughts?
  • Just like the Canadian commercials:

    "2**3021377 - 1, a prime number to call our own"
  • What about the Dinosaurs?

    The Dinosaurs didn't kill *themselves* off.. they just got screwed by a very large rock.

  • Because assuming that space aliens understand English would be pathetically stupid? If Star Trek has taught us nothing else - and it hasn't - its that all sentient biengs in the universe speak English as their mother tongue. This is of course at odds with the beliefs of the hitchhikers who get around that by sticking a fish [] in their ear.
  • I hope the encoded message doesn't have as many typos and grammar mistakes as the english translation I've been reading!
  • > To make an assumption based on current data, we have 1 civilization that has not managed to kill itself off, and 0 civilizations that have not. ... I realize until we have at least ONE civilization that HAS killed itself off, we won't be able to do a real comparison

    What about the Dinosaurs?

  • "...And this is the ultimate evil."

    "So when does it come?"

    "If this is the five... and this is the one... Every 5000 years."

    ...More Powerful than Otto Preminger...
  • I see the hidden agenda here - slowly, but surely, we are broadcasting all of Earth's pornography [] into space. This way, when the hammer finally comes down on the perverts here, we will have ensured the preservation of one of our most precious resources. Brilliant.
  • Whilst some elements of this message are very clever and clearly show a great deal of thought I find other elements very odd.

    As others have pointed out, the inclusion of the largest currently known prime is rather odd and would probably not help decode the message. It also introduces concepts like "raising to a power" in a very human-centric manner. Using some form of operator as is done for many other mathematical symbols would probably be much easier to understand. There is little point in using representative systems borrowed from our own evolved systems, rather than going for a totally new and clear system. Using a simpler base, such as binary, and maybe a system using postfix rather than infix notation.

    The symbols themselves seem to owe something to existing symbols, several of the numbers and symbols such as equality appear to be based upon our own symbols, I would have thought that using totally arbitrary symbol, with a great deal of redundancy (to allow for the inevitable noise and degradation in the recieved message) would make more sense.

    The use of arrows and lines pointing to graphs seems also to represent traditional human ways of doing things.

    Overall the message appears to be trying to say so many different things. I think they may have been better off trying to explain a few more simple concepts repeatedly, and in different manners, rather than try and show how "clever" we are.
  • If ET has 7 fingers on each hand, his numbering system might be base 7.

    Ok, I don't want to nitpick, but wouldn't their base be 14 (assuming they have two 'hands')?

  • The symbols are designed to withstand some noise on the transmitted signal. They are sufficiently big, and different, that a few flipped pixels will not turn them into another symbol, and confuse the recipient.

    Also, the code is sent in the form of simple images so that it is easy to include a few drawings. The invidual pages are also outlined by a single pixel, which should make it really easy to figure out that you're on the right track when you try to decode the message.
  • also.... the 'largest known prime' has all kinds of useful properties... it can be used as a chronometer... a sign that we're still kicking... our rate of technological advancement... a whole bunch of things. (some assume we send multiple msgs with a different 'largest prime'... btw there's a new largest prime since this was published)

    Then again... they won't hear the msg for another 300+ earth yrs.
  • Numbers are universal in many cultures. Well, the whole numbers are. We assume that it isn't an Earthly occurance in nature.

    How to translate a one dimensional string into a two dimentional diagram? More math. Not sure how to get 127x127 but for a previous message into space see: ci bo.html
  • by MrP- (45616)
    Obviously not, or at least not many... This story has been up for 20 mins now and the responces are so slow. Forget alien life, wheres life on slashdot?!
  • by FunOne (45947)
    2 + 2 = 4 (base 10)
    2 + 2 = 11 (base 3)
  • Thraag to Earth...Please retransmit page 00000.

    Seriously though - I wonder whether the diagrams
    would come across as anything meaningful. The
    various arrows and graphing conventions seem
    very human-centered.

    I was concerned that we sent them the value
    of Pi without a trailing '...' symbol. It
    kinda implies that we think it ends after
    the 51 billionth place or so. I guess aliens
    who actually bother to search through their
    100 billion places for those last digits would
    realise that we know that though. Still - it
    would have been nice to be more rigerous.

    The whole base-10 arithmetic thing was silly
    though. They should have studied the size of
    the character set they needed for the message
    and picked the highest power-of-two base possible
    within the limits of the transmission technology.
    (Probably hex - but certainly octal).

    In the first page, I'd have taken more space
    and put the numbers one to a line to make it
    clearer and more certain.

    Still, it's a good start.
  • Hydrogen * Pi _might_ make sense - but anything
    that's an interesting number of GigaHertz would
    only be meaningful to critters with 10 fingers,
    positional numbering schemes and the same
    definition of a second as us.

    If they use (for example) Roman numerals, they
    are gonna have a hard enough time decoding the
    message as it is!
  • If they respond, they'll (presumably) realise
    that we'll receive their reply hundreds of years
    after we sent our message.

    If they understood the message we sent then
    they know that humans only live for less than
    100 years (I think that was in there somewhere)
    so they should guess that we may have forgotten
    that we sent it - or what it was that we sent.

    It follows that intelligent aliens would define
    their terms in the same way we did - I think
    if I were them, I'd prefix my reply with a duplicate of the original message on the grounds
    that this would be the format that humans would
    be most likely to be able to detect and decode.
  • After hours of deliberation and a pass through my extra-terrestrial bound communications decoding algorithm, i find that the message reads

    FIRST POST!!!!

  • (Given the speed-of-light limitation, we won't have snappy conversation even if the other civilization is relatively close by.)What do we say? "Hi, were Humanity; here's as much of our understanding of the history of the universe as we've gotten so far; here's our understanding of physics and chemistry; here's how our biology works; here's the history of our species and the content of our various cultures." Does that about cover it? How many bytes do you estimate that breaks down to....a few Tb?I'd hate to be the guy who has to proofread everything.
  • by GoRK (10018)
    If we keep beaming weird looking crap like this into space, ET's are going to think we are a bunch of damn aliens.

  • "Stand by the grey stone when the thrush knocks and the last light of Durin's day will shine upon the keyhole."


  • If this is the sort of thing that "intelligent" life broadcasts into space in an attempt to contact other civilisations, then it's no fucking wonder we've not yet got any evidence that we're not alone in the Universe.

    Didn't some scientist put together a message like this, years ago, and show it to all his colleagues at a conference, only to discover that none of them could decipher it.

    And what's the whole idea with using pictures anyway? Before the aliens even get to figuring out how to interpret/understand it, they've got to get displaying it right (hmmmm - mental images of alien scientists rushing home to grab their kids' Atari 2600s).

    Why don't people who are trying to communicate with the rest of the Universe stick to the basics - i.e. morse code?

    Finally, given how much electromagnetic radiation the Earth radiates into space, what's the likelihood of an alien civilisation being able to pluck these sort of messages out from all the other broadcasts we regularly send out?


  • Oh right, so Morse Code was perfectly good enough for the very first wireless transmissions, but it's not good enough to broadcast into deep space?



  • Because assuming that space aliens understand English would be pathetically stupid?

    *sigh* I was operating under the unstated assumption that the message would be a mathematical one, seeing as maths is the only truly universal language.

    Why do you always have to spell everything out for Yanks? *duck*


  • Morse Code would be an extremely bad idea since it assumes the receiver understands English

    Ah, so it's not just Yanks you have to spell everything out for.

    I was taking it for granted that the content of the message itself would be mathematical in nature, as Star Trek's Universal Communicator is still under development...

    I swear, if you were to plot of the average IQ level of Slashdot users over time, I think we'd see something reminiscent of recent NASDAQ graphs.

    It's like, you're trying to have a conversation with someone, and you assume that certain things are taken for granted. Like, when I have a conversation about computers, I don't expect to have to declare up front at the start of each conversation that "PC" refers to IBM-compatible personal computers running Windows on an Intel-or-similar chip, or that "TCP/IP" refers to the suite of Internet protocols as defined by RFC numbers blah blah blah...

    It'll soo get to the stage where, in order to have any kind of meaningful discussion, you have to #define everything at the start...


    My point about the use of Morse Code or a similar method of communication is that it would remove the need for the aliens to be able to look at the picture properly. All they have to do is start listening to it. The use of "audible symbols" means that you can use maths to establish a ground set of rules that, later on, you can use to say, define how to display a picture like the one they sent.

    I just think that the biggest hurdle is the initial one - i.e. the alien realising that this is a message they're receiving. The simpler the message, the better, because you can build from very simple building blocks (e.g. a brick) to create longer, more complex messages (e.g. the Empire State Building) which go on to define universal constants like the speed of light, star positions, "We are here, come visit next time you're in the neighbourhood"-type of thing.


  • They start out by defining a series of symbols and methodology of representing base 10 numbers and equality using a set of (apparently) arbitrary symbols, by displaying the base 1 and base 2 equivalents. This seems fair, though I'm not sure I would have bothered with base 10.

    All mathematical symbols are arbitrary. There's nothing inherent about the symbol '=' that means equality. It is just a convention.

    For the purposes of this message, the symbols are defined. The numerals are defined by cardinality of sets. Base-10 is used becuase it is more compact than Base 2 and it is the base that we use more often.

    Similarly, the operators are defined on later pages. I haven't looked at the other pages in the message, but I would define + by referencing the special value 0, the identity element under addition. Multiplication is probably defined in terms of addition and exponentiation in terms of

    Even if the aliens who receive and decode this message don't know about this particular prime, they might be able to determine its primality using similar methods to those used by us to do so. As such, the primality test of this number is a pretty big brag on our mathematical abilities.
  • > The aliens must think we're really stupid and primitive with such a small prime earth record and probably don't want to talk to us. :-)

    Actually, that's the Intergalactic Protocol for deciding who gets to invade whom. If you know a bigger prime than they do, you probably have a more advanced technological society, and are therefore also probably able to kick their asses.

    And the neat thing about it is, it's really hard to bluff. If you just pick a big number and they know it isn' prime, then they'll know you don't know any real primes on that scale.

  • You forgot to consider the fact, that while we MIGHT kill ourselves off in a few years, it hasn't actually happened yet. It may never happen. However, even if it does, that doesn't necessarily mean that everything will be over and done with. Humanity may survive on a limited basis and over a few hundred or even thousands of years end up at the same point again (and may proceed to kill themselves all over again) Think Canticle of Leibowitz.

    Still, we have no statistical base to work from on this. To make an assumption based on current data, we have 1 civilization that has not managed to kill itself off, and 0 civilizations that have not. This means that there must be an infinite number of civilizations that have survived. (I realize until we have at least ONE civilization that HAS killed itself off, we won't be able to do a real comparison) :)

  • If this message is received by smart aliens intent on conquering systems then from this info they given that knowledge they should be able to build a weapon to wipe us off the face of this planet.

    Well, if they have the technology to deliver a weapon here across interstellar space and were motivated to use it, we're toast. They'd hardly need detailed intelligence.

  • A couple of posts have touched on the content but I spent quite a bit of time looking at all the pictures before reading the commentary here.. It's really a quite interesting set of 'questions' to the intended recipient, I was a little giddy with myself for seeing the answer at the end (I guess this is the facet of my personality that makes me a programmer).

    They start out with a simple definition of symbols, the symbol at the top of each page represents what 'state' of the transmission we are in, or what that pages info contains. The first symbol:

    x xxx
    x x
    x x

    Represents an introduction, a primer, if you will. The most interesting symbol on those pages is the 'what is' symbol, shaped roughly like a flower. They introduce some simple math then use that symbol to make the following statements (I've drawn the what is symbol as a %):

    %_ _+2=3 _=2
    %_ _+4=10 _=6

    and so on.. clear to see that the _ is an abstraction for 'x'. Later on down the page they use:

    %x _=x

    And they draw a picture of a cubic graph. The _ in this case is very similar to the x above, hinting that it is also a variable. In this case, y. I digress a bit. The most interesting symbol is the flower (what-is), for reasons I'll get to in a moment. In the sections that follow, we get information about ourselves:

    xxx x
    x x

    Including that symbol on a picture of our solar system in the spot for earth, that symbol in a model of the earth and moon, that symbol with a various arrows to show which way we spin and how long that revolution takes, symbols for elevation, the highest and lowest points on the earth (-11000m and 8848m), our size (about 1.5m), common molecules that appear in nature (my chem is terrible so I couldn't decode these, but I'm assuming they are common carbon based molecules), a basic picture of a cell and dna replication, and a picture of our earth.

    The best part though is that we introduced a new symbol for each of these 'measurements' with the 'we are' symbol I drew above. Paging through to the <a href="" >last page</a>, you'll notice a lot of the 'what-is' symbols next to all the symbols for our measurements of ourselves, along with a big what is symbol:

    x x x

    ... essentially asking, what are you? I got goosebumps, and I wait for the day where we get the incoming message with a symbol of their own introduced, for 'we are.' :)


    PS: gr, couldn't get the symbols to come out right, sorry. You'll have to look at the page. :]
  • Well.. why don't they just use *our* symbols, and teach ET that from the very beginning.

    Maybe it has something to do with export restrictions... :>
  • If you read on.. you'll see that the second page: l
    defines mathematical operators.

    Nearly the first thing that came to my mind when I saw the 2 (superscript)3021377(/) ? 1 was.... its a power with an operation followed by one... and since this whole page was about defining prime #'s... it must be (the largest) prime we currently know of. So the ? was either + or -.. .since 'even' numbers can't be prime... and you can't get an odd number by multiplying or dividing from 2. (And yes i figured that out without lookin' at the solution, in answer to your question 'did anyone figure this out?')

    Anyways... if the alien's had figured this out right away is really not important... its just one part of a very very long and complex msg... hell.. page 8 introduces Hydrogen's spectra... .0001% of the population of earth even knows what this is heh... and only the brightest minds of the alien species will be decyphering this text. If they have the technology necessary to receive this message... then they MUST possess all the knowledge in this entire text.

    Chances are they don't hear the message.. if they do... they might not realize the static is a signal. Then they've got to put it into a viewable page format (for them)... and they probably don't use base 10 as their standard numerical base... oh the complications are endless =]

  • That bugged me too. It was the only part that I couldn't easily figure out, although I did realize that the inner numbers were an exponent.

    It's particularly frustrating when you consider that the whole point of "universal language" communications like these is to take advantage of features of our universe that any alien species would necessarily share with us. That's what the primes are for... any species with enough technology to recieve the message would recognize the significance of those numbers. But what does 2^3021377 - 1 mean to an alien species? Absolutely nothing.
  • Why don't people who are trying to communicate with the rest of the Universe stick to the basics - i.e. morse code?

    Because assuming that space aliens understand English would be pathetically stupid?

    Don't get me wrong, I mostly agree with the rest of your article. But if you take a fellow Earthling who can't speak English, doesn't know the Roman alphabet, and isn't aware of the truly fucked-up spelling rules we use, and send him a message in Morse, he isn't going to get it either.

    Yet another consequence of speaking a language whose vocabulary came from German but whose grammar comes from Latin. :-)

  • If Star Trek has taught us nothing else - and it hasn't - its that all sentient biengs in the universe speak English as their mother tongue.

    Very true. In addition, Doctor Who also taught us that they speak it with a British accent.

    This is of course at odds with the beliefs of the hitchhikers who get around that by sticking a fish in their ear.

    Heh. I was just reading that book last night.

  • Why indeed ?

    This message is 127*127*23 (pix*pix*pages*). With "our" symbols, we would either have to lenghten the message significantly or raise the resolution of each of the pages.

    By using specially made, compact symbols, we can send a message that's easily readable by people, no matter what their language is or what symbols they use. A message that contains theory on number systems and complex number representations, equations, particles and waves. Measurement of pressure, power, energy, speed, temperature, time. The size of the planets, astronomical and geographical information about earth. Sensory capabilities, DNA, general appearance and other details about humans.

    And all of that takes what ? 46 kilobytes ! 46 !

    Creating that message is quite a feat if you ask me. It would have been impossible to do it that well with "our symbols".
  • "Yes sir we finally have confirmation, its a message full of swastikas. I'm afraid the Nazi party has taken over the world, begin the attack."
  • When we finally do make contact, their scientists, intellectuals, techheads and terminally ill are going to be seriously bummed out when they learn that of all the space aliens, they made contact with us: the race that came up with boy bands, electric nose hair trimmers, and beer dispensing hats.

    Do them a favor. Encode a message that says "Sorry, Keep trying. Aim a bit more to the left next time."

    "p.s. -- we apologize for any movies broadcast to you in the past, present, or future featuring professional basketball players. Especially Shaq. We are so so sorry about Shaq."
  • Not only is it conserving bandwidth, it's also exploiting one of the thought-to-be universally known mathematical concepts: primes. 127 is prime. The symbols are 5x7 pixels. Both primes. All in all this will help (hopefully) the recipients to line up the message.
    Hats off to the creators of this message. What frequency did they broadcast it on..? Hydrogen * pi GHz? :o)
  • If some aliens got this pictore of squigles, comprehended it and sent back a response in similarly encoded squigles who would understand it ?

  • Erm... maybe it's just me, but how are you (or they :) supposed to know that the weird, second-last glyph is a minus sign, and what it's for?

    Maybe I missed it, but I don't see it described anywhere.

    Also, what is the glyph in the middle at the top for?
  • In a statement released earlier today, scientists stated that due to a clerical error, the message had been compiled with a missing page without which, none of the message would make any sense to any alien trying to decipher it. That lost message can be viewed here []
  • Even if the aliens who receive and decode this message don't know about this particular prime, they might be able to determine its primality using similar methods to those used by us to do so. As such, the primality test of this number is a pretty big brag on our mathematical abilities.

    Actually, I don't think the problem is proving primality, I should imagine that this wouldn't take more than an afternoon on a reasonably fast machine. The problem is finding them. If I say "x is prime" it's trivial to prove (or not) by factorisation, if I say "Find the next prime larger than x", you have a (potentially) big big search on your hands for large values of x (I believe you'll have to search about x values or so).

    And as far as mathematical abilities go, it doesn't prove much. Only that we understand primes and that we have the ability to compute the factors of numbers on a speedy basis (which could be the domain of colonies of monks).

    I would say that probably one of our biggest maths brags would be calculus, an abstraction of physical properties (not that there aren't more impressive maths feats but it's the first which starts to peel back the layers of the universe being "invented" to describe gravity as it was)


  • If you've seen the movie Contact, it's entirely possible to encode details information into a signal that can first be interpreted as a simple artificial signal.

    And if you've seen Superman, it's entirely possible that there's a guy from Krypton flying around upholding the law.


  • Is it just me, or does the image [] bear a shockingly uncanny resemblance to Space Invaders []?

  • Such pictoral messages are unlikely to be very effective, if ever encountered by an alien intelligence; they are too human-centric and require way too many assumptions about visual acuity and pattern recognition and the ability to understand letters. Even people used to some languages on Earth would have great difficulty understand it. What's more, the actual transmission that was actually sent had typos in it! Nice job.

    Raw transmissions such as Lincos like languages are largely mathematical, have no required geometrical interpretation to be understood, and are much more straightforward to decipher.

    For an example of a Lincos-like language that was easily deciphered by amateurs, see The Contact Project []. For an example of what Lincos "looks like" (it is actually a radio transmission, see Excerpts from Lincos []. For more information on extraterrestrial intelligence and contact, see my Extraterrestrial intelligence links [].

  • 2 + 2 is 5 for very large values of 2.
  • Looking at the first 16 posts I am not convinced there is any intelligent life out there.
  • If you do not agree with the terms of this licence, return the planet to the OEM you obtained it , or destroy the planet and any 'backup' copies you have. The abovementioned planet is for evaluation purposes only and will BECOME UNUSABLE after 30 days.
    --Bill Gates. Emperor of Earth(tm)
  • I've always wondered, these messages that we send out are supposed to be simple enough for another civilization to decode once received; but what work goes into sending an easily recognizable message?

    On SETI's page, they talk about a natural area of the radio spectrum where cosmic radiation does not interfere, and therefore this would be a good area to listen for communications which are meant for us to hear.

    Are the messages we send out, also sent on this frequency? Has anybody ever taken a message such as this and analyzed the probability of a software program such as the one SETI uses recognizing it?

    Do we take into account signal loss, and doppler effect when analyzing our own signals - to get a feel for how an alien race would analyze them were they to receive them in another galaxy?

    Sure, we are definite they would receive the signal, but would they know it? By the time it reaches them, it may be full of static, or the timing may be too slow for a clear understanding of its intelligent origin; after all, if you were to scan a particular region of space, and for an entire day all you heard on a small frequency was a single strength of signal (a single pulse), you might be inclined to ignore it; believing it is regular noise from a distant cosmic event

    I would like to know more about the science which goes in to the transmission of our own signals.
  • People are talking about posting more complicated messages to give instructions on building devices for communication.

    In the least, this would show a need for communication between ourselves and another civilization; I believe it would be possible for 1 very simple reason.

    The periodic table is as self-evident to an advanced culture as the number system, elements are formed in the table one after the other, and so with a little work we could send anything so long as we use diagrams.

    I think it would be a great cosmic disaster to send plans for an atomic bomb [] to a race which has just mastered radio communications; what's more is, it would be very very funny.

  • Well, on the next few pages of the transmission, the explanations of +, -, and power notation are given. It would be difficult to comprehend that line without the rest of the message, definitely. Matt
  • OK, you've compared unary to radix-1000.

    You've forgotten binary.

    Remember, the binary symbols are much shorter than radix-10 ones, as you don't have to error detect/correct between 10 different symbols. You could stick one bit in 4 pixels and have better error resistance.
    Mapping the whole thing into base 10 is anthropocentric nonsense (no disrespect to the Babylonians)

    The aliens will read it, see the first page and say "these stupid creatures can't decide which base to use"...


    -- Real Men Don't Use Porn. -- Morality In Media Billboards
  • I think it would be a great cosmic disaster to send plans for an atomic bomb to a race which has just mastered radio communications; what's more is, it would be very very funny.

    That is the funniest damned thing Ive read here in weeks. Images of 1900's earth people constructing what they believe to be a wondrous machine of ultimate salvation - only to have it go -BOOM- during its grand 'coming out party' infront of many many millions of people... its almost sad that I thought _that_ image was funny... time to see my councilor again.. ;)
  • Lets not assume if they receive this message it will be clear. Earth bound people have created a single paradigm for 'written' communication: 2 dimensional images on a flat surface. It is highly unlikely that another civilization uses this same paradigm. Consider: Who's to say that these Aliens wont use a system of arranging 3D rings of differnent colours to convey information. Whats to say they dont simply vomit on the floor and play with it with their appendages? Who says they have appendages? Maybe they blow smoke rings - or exhale globs of frozen methane which they then decorate their 'bodies' with to convey messages??? Who's to say they will have the faintest clue?

    By the same logic; are they already sending messages to us? Maybe we are receiving/seeing them and are just so oblivious to their 'communication paradigm' that we dont even recognize it? Maybe the craters on the moon have been 'purposely built' to convey information to us? What about weather patterns? or the frequency of comets?

    If these Aliens receive our message I find it very unlikely they will decifer it - they will try to apply the patterned info send in the radio waves to their paradim: and trust me; it wont look like that page of 'digits' we sent...

    Do I think this is worthwhile? Absolutely! Its the only method we have - the reward is so great it is beyond imagination - the exploration/colonization of space should be the #1 priority of the planet, instead it seems we have chosen 'other' priorites (consumerism). Really a sad fate for us all - I just hope 250000 years from now 'we' have our priorities on this straight on this planet.

  • If the alien figures out a stream of 0's and 1's, how does he know that they represent 23 pages of 127*127 pixels?

    Have you ever looked at a stack dump? I mean, even without being a programmer, you've seen them. But have you ever really looked at one?

    When you start to see a pattern of, let's say, 65,535 random characters with a $ sign, then another 65,535 random characters and another dollar sign, can't you maybe make the assumption that you're dealing in 64k pages of information? If you then start to use the dollar sign as a sign to start a new line, then a pattern might become visible in the contents of the stack dump. (And, no, don't get highly technical on why this stack dump is wrong, it's an example.)

    Each line that is being sent is 127 pixels long. At the same places in each string of seemingly random dots, there are pixels that mark the "edges" of the information.

    Further, even Hellen Keller could see that there was intelligence at work if she saw this coming into the instruments on her radio telescope. It would be given close scrutiny.

    Mathematics are universal. It doesn't matter if you write 2+2=4, or 0010 + 0010 = 0100, or even II + II = IV. The values and fundamentals are universal. If ET has 7 fingers on each hand, his numbering system might be base 7. But if he's got the technology to be building a radio telescope, he's got higher mathematics. And that means he's got the lowest and simplest mathematics there is: binary. And while there can be no standard way of writing the symbol between two lifeforms that have evolved completely different, it remains: There are two characters, On or Off. However you draw them.

    Remember: 1001 = *..* = fyyf = etc.

    If someone were to write this:

    ^^#^ + ^^## = ^#^#

    And put it on a mathematician's desk, he'd figure it out in seconds.

    Since they will know binary, and they'll know that another creature trying to make contact is likely to use it because of its simplicity, my bet is that they'll try to look for patterns on 1, 2, 4, 8, 16, 32, 64 ...and *128* in the incoming data stream. Right where our page edge markers are.

    Build your own pay TV decoder for fun. You'll see that deciphering what appears to be random information really isn't all that tough. This is a walk in the park compared to some of the math that people get into in daily life. Let alone pure research scientists.

    ET wouldn't have to be all that bright to figure it out. He *would* have to be far brighter to build the equipment with which to receive it.

  • If this is the sort of thing that "intelligent" life broadcasts into space in an attempt to contact other civilisations, then it's no fucking wonder we've not yet got any evidence that we're not alone in the Universe.


    Okay. How is time measured? In days, hours, minutes, seconds - right?

    All stuff that's based on the properties of the orbit of our planet. A planet that they've never seen before, and until this message, have no idea where it is.

    Their planet may spin slower than ours. What we measure as a second here may well actually take 34 of our seconds on their planet.

    What's that mean? It means that when we try to describe basic properties of distance in our units of measurement - like light years, for example - their light years would end up being different from ours. Essentially, then, they'd receive a message that displays intelligence, but demands that they use references that they don't have.

    What's the distance between the Earth and Sun? Going to measure that in kilometers and send it to them? How do you describe a kilometer over radio waves? You can't send a reference unit of 1m, you know. You can't tell them it's approximately the length of the recipient's left arm. What if the reader has tentacles?

    *Everything* has to be defined clearly in a mathematical sense. Anything that isn't probably won't have a reference that they can understand.

    Sending them video of Three's Company or something would tell them a lot about us. An NTSC TV signal is repetitive and therefore could be quite easily dissected and displayed by an alien culture. But what would Three's Company say about us or our world? And how many minutes of Jack whining could you get to fit in under 64k of highly noise-resistant signal?

    So, with this new understanding, what do *you* propose is a better way to get in touch with ET? What do *you* suggest will tell him the most about us?

  • Ok, I don't want to nitpick, but wouldn't their base be 14 (assuming they have two 'hands')?

    That's a hell of an assumption. What if they have three hands?

    Or, what if, somewhere in their history, a leader had decreed that one hand must remain at all times on their genitalia? Continuing the assumption of two hands at 7 digits each, they'd still only have one hand with which to count. Their number system may have grown up with that and despite their equivalent to the sexual revolution of the '60s, maybe they have a tradition of using only base 7 as a result.

    I think the point I was making is that you can *never* make any assumptions about who might be out there - everything that we take for granted has to be sent to /dev/null before any relevent communication, beyond basically a sign of unintelligible intelligence (!), is possible.

    Too wacky? I think not.

    Look at us.

    Our height is commonly measured in units based on, and named after, the length of a dead king's foot. A king that wasn't even *liked* on this continent.

    As if that weren't enough, we confuse the issue. Smaller divisions of that unit aren't "half-feet" or "quarter-feet" or even something intelligent like decimal divisions of feet. They're inches. Based on the width of the same dead king's thumb. (Since we're already basing the principal unit of length on his foot, why not designate the smaller unit after the width of his big toe?)

    Our calendar is based on the circumcision of a religious figure who allegedly was born 2,000 years ago. (And, because he was Jewish, the calendar recognizes the Jewish tradition... it's not by accident that New Year's is exactly 8 days after the accepted date of celebration of his birthday.)

    Now, I'm not making any big statment here. It's easy to look again at things we take for granted. For one thing, a foot is an easy principal measure of length, because you can basically pace out a distance. And a few inches can be measured by pacing out a thumb.

    But without a reference, a baseline, an understanding - much of which is impossible to convey without a common language - there's no way that anything but pure mathematics based on immutable elements will ever make sense.

  • (4) an alien intelligence in at least one target location that will have a 1 km^2 radio anntenna array and will have detectors tuned to 5 GHz;

    It's not as if radio antennas are limited to one frequency (or even any finite number of frequencies) at one time. Perhaps you've heard of Fourier transform?

  • when they are probably too busy trying to decipher the meaning of all the Leave it to Beaver episodes.
  • []

    "And this, Mr Alien, shows you just how memory intesive Windows is..."

  • I'm sure I saw something on the TV about an international treaty which banned deliberate attempts to contact extraterrestrials, on the grounds that they might come and eat us.

    Couldn't find it after a few minutes' googling, so perhaps some of the UFO nuts out there could provide a link or a refutation ....


  • I sat down with pen, paper, and a calculator, and figured it out, using my extrodonary mental powers. It says "first post". :)
  • We as humans believe we have come a long way in science and technology. Yet our own SETI program is simply looking for any simple artificial signal that has a clue intelligent life. Since that is what we are looking for shouln't we be sending that type of signal. A very simple short and repetative signal. Instead many seem set on sending math equations and DNA sequences that may otherwise be missed by other worlds simply looking for a just simple sign of life. Instead they keep trying to send the Libray of Congress. It would thing It would be more effective to send a simple straight forward repeating signal such as a rising and falling tone followed by a short beep. Kind of like a FAX carrir signal. Just let them know we are listening.
  • by gelfling (6534) on Wednesday January 10, 2001 @04:51AM (#517522) Homepage Journal
    Not those damn earthlings again! dump 'em in the bit bucket and block all future messages. Stupid kindergarten drivel !!!! Stupid earth trolls. Fuck em.
  • by Kozz (7764) on Wednesday January 10, 2001 @05:54AM (#517523)
    The alien reply will be:
    "Attention all planets of the solar federation.
    Attention all planets of the solar federation.
    Attention all planets of the solar federation.
    We have assumed control.
    We have assumed control.
    We have assumed control."

    Quidquid latine dictum sit, altum viditur.
  • by Black Parrot (19622) on Wednesday January 10, 2001 @02:10AM (#517524)
    And it says,
    By opening this message, you agree to hand over all your tangible assets and intellectual property to the sender.

    Moreover, you agree to use our spyware without complaint, to read all the spam we send you, and to buy at least 12% of the products offered.

    You are entitled to forward this message to any two additional planets that have not already received it, but half your proceeds from that act must be forwarded to us, 1/4 quarter to the assholes who sent us this message, 1/8 to the assholes who sent this message to them, and so forth, yea unto the seventh iteration.

    To opt out of further offers such as this one, please paint your entire planet pink and notify us of your IG address so our astronomers can verify it. Be warned that they will watch your planet for a complete rotational period, so do not skimp on painting the far side. Please include 3 Union currency to cover our expenses.

    Notice that opt-outs are only valid until we decide to reset our database to the default values. At such time you may be required to pay an additional small fee if your settings did not correspond to the default at the time of the resetting.

    Disputes pertaining to this contract shall be settled in the courts of the Commonwealth of Virginia on the Planet Earth in the Milky Way Galaxy.

    If you do not like the terms of this license, please contact your friendly Customer Service Representative at 347 5417, 455 4013.

    Thank you for being a sucker.

  • by Black Parrot (19622) on Wednesday January 10, 2001 @02:47AM (#517525)
    > And what's the whole idea with using pictures anyway? Before the aliens even get to figuring out how to interpret/understand it, they've got to get displaying it right

    The real tragedy is that it was received on Achernar VII, where the symbol for "=" looks like their 2/3males, the symbol for "1" looks like their 2/3females, and the symbol for "2" looks like their 1/3male1/3females, and the combination "=12" at the middle right, which uses those three symbols, looks like a carnal conjunctive configuration that is not approved by their majority religion. Worse, if they count to 12 on their fingers it leaves the hand in the shape of an obscene jesture.

    We are now at war with the Achernar VIIlings. Their High Thwip has ordained 3.26 fippur lashings for every citizen of the planet that sent the foul message, as soon as his god teleports us there so he can administer them.

    May our own gods postpone that day: they're really going to be offended if they discover that we don't have fippurs to receive the lashings on!

  • by hey! (33014) on Wednesday January 10, 2001 @04:42AM (#517526) Homepage Journal
    If they already know this prime it's be pretty easy; especially if they had anything like 'IT'. I tried a google search on 3,021,377 and in turned up lots of stuff about (2 ^ 3,021,377) - 1.

    If they don't know this prime already and don't know about Mersenne primes, it's going to be pretty tricky, but they may be able to figure it out given that they can decode later parts of the message. Maybe they'll start looking into Mersenne primes if they didn't know them already.

    I think encoding some non-obvious data is a really interesting idea. Sure, start with the lowest primes, but once you get past 13 or so you're just wasting space -- they're sure to have figured it out and if they haven't its hopeless. BUT -- when the first alien geek figures this out, there is going to be a moment of "aha" -- a meeting of minds across interstellar space.

  • by pete-classic (75983) <> on Wednesday January 10, 2001 @03:59AM (#517527) Homepage Journal
    They must have used windows to make this.

    I'm getting an extra ^M at the end of each line. This is sure to cause "stair stepping," as any superior alien race is sure to be using UNIX.


  • by Richy_T (111409) on Wednesday January 10, 2001 @07:55AM (#517528) Homepage
    Don't understimate the power of "2d" surfaces. After all, out primary method of communication for millenia is 1d (speach) yet even cavemen were painting pictures on cave walls.

    With light impacting a 3d object, you get a surface, patterns on that surface will be "2d" information and for any image processing organ (eye) worth its salt, will be projected onto a "2d" receptor (shadows, facial markings, body language).

    It's a fair bet (though by no means certain) that any species capable of using visual communication media will use something "2d". Of course, that's not to say they won't use others, we do ourselves after all (sculptures etc).

    Note that I use "2d" not in its strictly correct definition to make my point


  • The linked page is the first of 23 such images that made up the complete transmitted image. Here's a list [] of all of them.

  • by alexburke (119254) <slashdotmail@ale ... minus physicist> on Wednesday January 10, 2001 @01:14AM (#517530)
    Some of the other 22 images making up the complete transmitted message deserve, IMO, a closer look:

    A lot of thought obviously went into the preparation of the complete message. My hat's off to the team that came up with it!


  • My bad: these two images are two halves of one image (indicated by the alignment marks on the right-hand side of 19 and the left-hand side of 20) and depict Earth's continents in today's layout, but with an East-Up layout that confused me at first.

  • by T. (128661) on Wednesday January 10, 2001 @01:52AM (#517532)
    I am surprised that this sort message has not been sent out many, many times already. But, after reading the links, it appears that this is the longest message and the first since 1974. (Correct me if I am wrong here.) It would seem that the chance would be vanishingly small that any alien intelligence will intercept this message as it would require a series of increasingly improbable events. To see why, consider what is needed for successful reception (ingoring the possibility for successful message interpretation): (1) An alien intelligence; (2) an alien intelligence in at least one target location; (3) an alien intelligence in at least one target location that will have a 1 km^2 radio anntenna array; (4) an alien intelligence in at least one target location that will have a 1 km^2 radio anntenna array and will have detectors tuned to 5 GHz; (5) an alien intelligence in at least one target location that will have a 1 km^2 radio anntenna array and will have detectors tuned to 5 GHz and will be analyzing signals originating from our region; (6) an alien intelligence in at least one target location that will have a 1 km^2 radio anntenna array and will have detectors tuned to 5 GHz and will be analyzing signals originating from our region for one of 60 of a possible 180 minutes sometime within the next 70-100 years. Now, being intelligent ourselves and seriously hoping that this far-fetched scheme works, why are we not sending these messages out more frequently? Was the message SETI is hoping to recieve sent out 20 (or even 20 million) years ago?

  • Anyway, a Hebrew or Arabic puzzle would have just been a mirror image I guess. And I am sure this puzzle will get distorted on transit by not being in the ET's network byte order.

    It's amazing just how difficult it is to describe things that you and I (and all people) take for granted.

    Like describing temperature. You can't give it in degrees Celsius or Fahrenheit - those measurements evolved on Earth. They're referenced to things on Earth.

    You can't even give it in degrees Kelvin, because their scientific scale could well be based on something completely different. From absolute zero to the temperature of a sunny day on their planet?

    So, you have to define an atom. Then, you have to define a few basic elements. And then the compound H2O, which still has the same atomic composition, though instead of calling it water, they'll recognize it as something they call NNGrlap. They love to ride down NNGrlap slides on days when their planet's star shines brightly on the land. And, on the remotest of possibilities that they've never seen water - under any name - they'll figure out how to make it. If they have the ability to make a radio telescope, they understand enough chemistry to know that hydrogen and oxygen react together. So, even if oxygen is a rarer-than-palladium element to them, at least their scientists will have seen it, documented its properties, and will be able to make water so that they can understand our standard.

    It's more likely, though, that ET will simply slither (or whatever) down the hallway, and turn on the faucet in the office kitchen to get a beaker full of NNGrlap.

    Once ET is familiar with the basic properties of NNGrlap/Water, you can establish a descriptive and meaningful temperature measurement of things that only we have seen.

    The fact that every measurement has to be described and that whatever the recipient's language is, it's going to be far different from *anything* we know on this planet, means all communication must be mathematics.

    Like reading graffiti in Aramaic, you don't need to know anything about Aramaic to know that the patterns on the wall aren't by accident. But, unless you've had some expose to the culture, you won't be able to make sense of it on your own. They'll have had no experience to our cultures. Therefore, any human language is not useful.

    Not to mention the fact that it could well take 1,000 years for the message to travel to a planet and be read by someone, and another 1,000 years for it to come back. What did English sound like 2,000 years ago? Didn't exist? Who is to say that it will still exist 500 years from now, let alone 2,000? So, if they managed to decipher a human-language message, and reply to it, our decendents will probably have a tough time understanding it. Ever read Beowulf? (Not the cluster, the old English poem). Think Shakespeare was tough? Try Beowulf []. And that's only 1,000 years old.

    In mathematics, 2+2=4, no matter how you write it. If they've got the technology to receive a signal from space, they've got mathematics. They'll be able to figure out the message.

    Consider the ground that was covered in that message. We defined *everything* in 23 pages of low-resolution dots. We described DNA. Maybe in a galaxy far, far away, the project manager of the radio telecope is going to be standing at an NNGrlap cooler, chatting with a fellow employee, when a scientist will come running in, show him the page, and he'll drop his glass of NNGrlap with surprise at how they're based on the same basic DNA structure as we are.

    We covered the spectral responses of our senses of sight and hearing. That will be important if they ever follow the directions we gave them and come to visit us. It'd be tough if they communicated in ultrasonics... :)

    All this ground was covered. And anyone, regardless of language, with some scientific interest, could figure it out.

    Mathematics is the only universal language. Not that it's practical for conversation...

  • by Sabol (210513) on Tuesday January 09, 2001 @11:23PM (#517534)
    maybe they know what 'IT' is!
  • by Fortyseven (240736) on Wednesday January 10, 2001 @04:33AM (#517535) Homepage Journal
    ...Incoming Patch...

    What's New:

    - Updated largest prime.
    - Added new page with my world (now galaxy) famous chocolate cookie recipie.
    - Removed Iraq from world map just to be a jerk, but may return in a future patch...

  • by AftanGustur (7715) on Wednesday January 10, 2001 @12:12AM (#517536) Homepage
    Holy Cow,
    this is almost plaintext in the Furth language, just shifted 13 places in the alphabet.

    The message reads:

    Greetings Furths,
    The race of humans has just learnt of your existance, after polluting our own planet, strip-mined it and centuries of brutal war with machines of devastating descruction, we finally found your planet.

    Please prepare for our resource probe fleet, due to land in 378 years (203 Furth years).

    Looking forward to meeting you.

    - The Eartlings

    Why pay for drugs when you can get Linux for free ?
  • by samorris (125056) on Wednesday January 10, 2001 @12:32AM (#517537)
    Unless I missed something, I disagree with their method of denoting the "largest prime found so far"...

    They start out by defining a series of symbols and methodology of representing base 10 numbers and equality using a set of (apparently) arbitrary symbols, by displaying the base 1 and base 2 equivalents. This seems fair, though I'm not sure I would have bothered with base 10.

    They then include the first 24 prime numbers using the notation introduced above, which seems good.

    Then suddenly they jump to including something that the decoded as:

    2 ?1

    with the "?" being a symbol that was not included anywhere else on the first page. This caused me quite a bit of confusion... especially the unknown symbol. I was beginning to think they had made a typo, or that it was one of the number symbols garbled. It looked more similar to the number symbols than the equality symbol, so I assumed that it was a number or letter, not a non-number symbol, such as a arithmetic operation or decimal point.

    The number itself didn't seem to give any hints either... I was assuming that it was going to be something like pi or the natural log of 10... but the number wasn't familiar.

    Turns out they intended this to mean 2**3021377 - 1, which they claim is the largest prime found at the time this was written.

    This seems unnecessarily confusing for some poor alien trying to figure it out. In one step, they introduce a new symbol (without any context), indicating substraction, a method of denoting exponents (without introducing exponents), all to describe a number that provides someone trying to decode it no clue as to what the new symbol and new denotation mean.

    Did anyone else figure out the "largest prime" on their own? Is there some other clue that I missed?

    -- Scott

Time to take stock. Go home with some office supplies.