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After 35 Years, Another Message Sent From Arecibo
0xdeadbeef writes "Two weeks ago, MIT artist-in-residence Joe Davis used the Arecibo radio telescope to send a message to three stars in honor of the 35th anniversary of the famous Drake-Sagan transmission to M13 in 1974. It was apparently allowed but not endorsed by the director of the facility, and used a jury-rigged signal source on what will now be known as the 'coolest iPhone in the world.' The message encoded a DNA sequence, but no word yet on whether it disabled any alien shields. You can get the low-down on Centauri Dreams: Part 1, Part 2."
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If this transmission stimulates even one young person to do that calculation for themselves, or to otherwise conclude that it's a foolish waste of money, it will have been money well spent.
We are very tasty snacks! Here, have our DNA, and grow some appetizers for the long journey!
I suffer from attention surplus disorder.
We could never pick up a radio signal from an alien civilization because the power of a signal from a point source drops off exponentially..
Umm..... its not a "point source" its a spherical reflector..... the whole point of the construction of big antennas is to allow you to do precisely what it is you friend appears to believe is impossible.
We now return you to your usual /. chaos
-jon
Actually I believe calculations have been done which show that two Arecibo type telescopes could communicate across the galaxy.
http://michaelsmith.id.au
Without any context --- e.g., our biochemistry, amino acid structure, nature of DNA --- this message amounts to about the worst practical joke in the history of interstellar communication. It has a relatively non-random structure, so clearly must mean something, and yet they'll never figure it out.
Dear citizens of Centauri. I have a large sum of gold, 300 metric tons, I need to move off planet. If you'll deposit a small transfer fee, 3 metric tons of gold, in a local bank I will make arrangements to ship the gold to you. Signed crowned prince of Iowa.
These guys must be loaded. Would you believe the rates they're charging for interstellar calls?
Oddly, we just solved this problem in E&M class. If you had antennas with 80 dBi gain at both ends and a megawatt of power, that would be sufficient to transmit 10^5 bits per second over a lightyear gap with a received power level above the thermal noise floor (e.g. the antenna does enough work on the receiver to flip a bit). Raise the distance to 100 lightyears and reduce the gain to 73 dBi (e.g. Arecibo) and you lose 5.5 orders of magnitude in bit rate. Up the power to three megawatts (not hard to imagine) and you get back half an order of magnitude. So the achievable rate over 100ly using only current Earth technology at both ends is about a bit per second. Useless, perhaps, but not technically impossible.
Not to mention the fact that even point source radiation falls off as the inverse square of the distance, which isn't at all the same thing as falling off exponentially.
One bit per second is good enough for the Navy...
http://michaelsmith.id.au
This just in - they got a response:
Dear Earthling,
Hello! I am a creature from a galaxy far away, visiting your planet.
I have transformed myself into this text file. As you are reading it, I
am having sex with your eyeballs. I know you like it because you are
smiling. Please pass me on to someone else because I'm really horny.
Ok, I understand the "coolness" factor of radio transmissions to the stars, but in the end are they all wasted money? I mean, chances are another Hubble mixed with other probes can find where there is other life faster, quicker and easier than radio telescopes. We've been trying these for ages and they haven't picked up anything. So why not spend research money doing things that we know are going to work. Plus, its a whole lot more probable that we will find non-intelligent life throughout the universe than intelligent life. Even if we find life outside earth with the technology level of 1700s earth, they won't be picking up these signals and really for all but the last 100 years, humans wouldn't have been able to pick up this signal. So quit messing around with radio signals and find possible planets for life.
Taxation is legalized theft, no more, no less.
You have no idea about what you are talking about. It is true that omni directional radio sources are subject to inverse square law, but directional signals degrade less slowly. Scientists have calculated that using the Arecibo dish at one megawatt the signal could be received by a similarly sized dish 10000 lightyears away. I think I trust calculations done by people with PhDs in astronomy more than calculations done by you and your friend
The entire Wikipedia section on the production of titanium is a little under 4 kilobytes, which would take a bit over an hour to transmit at those rates. Imagine an alien species has a new ultra-efficient titanium refining process - would you wait a day to get the summary of it downloaded for your scientists? I sure as hell would.
The two-hundred-year transmission lag to go a hundred lightyears is a far bigger issue than the bandwidth.
Breaking Into the Industry - A development log about starting a game studio.
I'ma let you finish, but we already got a reply to the original message!
--
"Open source is good." - Steve Jobs
"Open source is evil." - Microsoft
We could have rickrolled them so they could get a taste of our culture!
Sending out a DNA sequence assumes that the receiver understands a great deal about our planet and the molecular basis of life on it.
Think about it, even if they understood the message was about DNA, they would have to know our amino acid code in order to interpret it as the template for a protein. A protein that either did not evolve on their world, or evolved in a completely different way.
In effect, all we saying with this message is that we have advanced enough to recognize that DNA is the basis for life on this planet. Only a sentience that already understood that basis could interpret this message.
It's akin to someone shouting, "a-squared + b-squared = c-squared!" - out-of-context - in the antarctic. It shows you have learned something, but there either isn't anyone to hear you or they won't understand you unless they knew all about you (and Euclidian geometry) already.
My Dear Friend and Earthling, My name is Mr. Zebel Braumat, I am a senior priest in the highest order of our race. We are conducting a standard process investigation/Recommendation on behalf of all Advanced Common Civilization (ACC). This investigation involves an ancient race who shares similar DNA as with yours from which we have previously received messages from. The circumstances which surrounding investments made by this race at ADB Gold Account, the Private Banking arm of ACC. The ACC Private Banking client died intestate and nominated no successor in title over the investments made with the bank amounting to over galactic 9.5 Gazillion dollars. The essence of this communication with you is to request that you provide us information/comments on any or all of the four issues as regards nominating your race to inherit the fund left behind by this previous race. You are therefore being contacted to be legally nominated as next of kin(inheritor) to this race after all enquiries and investigation has yielded results showing that there is no known successors. You are required therefore to answer this questions to enable us make our recommendation. 1-Are you aware of any relative/relation born on the 2nd of February 1951, who shares your same name whose last known contact address was West Africa? 2-Are you aware of any investment of considerable value made by such a person at the Private Banking Division of ADB Bank PLC? 3-Can you confirm your willingness to accept this inheritance if you are legally and legitimately nominated and approved to stand as inheritor to this huge investment in regards to the bank account with ADB? 4-Would you agree to donate part of this inheritance to charity if you are officially approved to stand as the inheritor? It is pertinent that you inform us ASAP whether or not you are familiar with this personality or and your interest towards the issues mentioned. You must appreciate that we are constrained from providing you with more detailed information at this point. Please respond to this mail as soon as possible to afford us the opportunity to provide you with more information on this investigation and recommendation. Thank you for accommodating our enquiry. Mr. Zebel Braumat For: Advanced Common Civilization Kappa Ceti (G5B)
So if you're going to send a message, you have to choose one. What did he choose? The DNA sequence for an enzyme.
We used Apple's "Speak" option to vocalize the phonetic code which I then recorded on my iPhone. Here is a fragment of the total message, the whole of which can be decoded unambiguously into the gene for RuBisCo:
Tell me how, exactly, the recipient is going to decode a DNA sequence, even if the basic message can be identified as strings of 2-bit numbers? Not only is DNA specific (as far as we know) to Earth chemistry, but the meanings of the codons, and even the choice to interpret them in triplets is the result of chance evolution on this planet. It's like sending a message in Navajo to Paris, with the assumption that it can be "decoded unambigiously"... because the sender knew what it meant. The meanings of DNA codons are absolutely not a universal constant like binary math is.
knowyourself riddleoflife amthe riddleoflife amthe amthe riddleoflife riddleoflife
<facepalm> Not that the choice of words would mean anything to them, but this shows the touchy-feely-ness that goes along with the lack of foresight that was already demonstrated.
Say what you will about Sagan's message, but at least they put some thought into making a message that gave hints as to how to decode it, rather than just sending some unframed binary mish-mash.
--
"Open source is good." - Steve Jobs
"Open source is evil." - Microsoft
it's like a radio time capsule.
Imagine if what becomes of humans in 1 million years or so intercept the transmission. It would be like digging up an old fossil record of DNA.
Science advances one funeral at a time- Max Planck
Not in my lifetime.
Radio waves aren't made out of photons?
But they did use an iPhone.
http://michaelsmith.id.au
+3 Interesting, huh?
This (and some previous, as well as some following) comments, have absolutely no clue whatsoever about E&M radiation. If you don't know, don't post.
The strength of electromagnetic radiation drops off as the square of distance. (As long as you're far enough away to ignore "near-field effects", which for the astronomical distances we are talking about, they can very well be ignored.)
It is always the square of the distance no matter what antenna geometry, gain, feed, or other technological measure is employed. It is not exponential (as stated by a previous post). They do not degrade "less slowly" as stated in the parent post. (And - "less slowly" - does that mean they degrade more faster?)
I swear, I hardly ever post here, but I'm going to have to create an account just so I can reply to all the erroneous understandings of E&M that get modded up. I expected this readership to be better than that.
Exactly. I don’t think the phone model would have been mentioned (and with a wink nonetheless) that way if it were another phone.
Besides: Even a iPhone that sent stuff to another planet and got a reply, can’t beat a Linux running Nokia N900 with built-in full root access, from a company whose phones had SSH terminal software available for more than seven years now. </proper-geek-fanboyism> ;)
Any sufficiently advanced intelligence is indistinguishable from stupidity.
Not in my lifetime.
But maybe mine. I plan on living to be at least 500, hopefully more. So far, so good.
I don't like Linux. This doesn't make me a troll.
No. The signal strength is 1/(r^2). Exponentially would be 1/(c^r), where c is some constant and r is the radius. Exponentially means r is in the exponent, not the base.
Well, because we already broadcast enough, so sending yet another message does not really matter anymore. What I worry is our regular TV programming, which in the eyes of any advanced culture should make earth look like it's populated with some crazy monkeys flinging shit at each other.
As it is a linear partial differential equation, all solutions to the wave equation and equations of its type are governed by what is known as the "fundamental solution" or "Green's function" of the equation. In the case of wave type equations(in 3 or more dimensions), this solution will be a delta function type solution which decreases inversely with distance from the source. Squaring its amplitude to obtain energy gives an inverse square energy decrease.
It must be stressed that all solutions of the wave equation, no matter what the sources, or boundary or initial conditions, must all be functions derived, more or less, from convolutions of the fundamental solution with the source terms. You cannot escape the inverse square behaviour of wave propagation over long distances with finite wave sources. The fundamental solution characterises all waves because of the linearity of the wave equation.
Now, there is a second fundamental solution for the wave equation; the so called "acausal" Green's function, which represents an inwardly collapsing wave, or by some conventions, a wave travelling backwards through time. Naturally, these waves are not considered in the context of the transmission of signals. Even if they were, these waves also display and inverse square relation for signal strength( going backwards in time of course).
This has been your daily mathematical public service announcement. Complaints to be directed to the Dean.
May the Maths Be with you!
In the science fiction story "Dragons Egg" by Robert L Forward (who was incidentally a physics professor and described the book as "a textbook on neutron star physics disguised as a novel"), a spaceship beams the entire contents of their encyclopedia to creatures living on the surface of a neutron star at high speed. By the time they are halfway through, several hundred generations have passed and the creatures have solved all the problems that remain to be sent, have built spaceships of their own and are knocking on the hull. One of my favourite books ever, describing the postive viewpoint of giving knowledge away for free.
There are negative viewpoints though, such as presented by Gregory Benford (also a physics prof, and another of my favourite authors) where broadcasting anything attracts the attention of machines whose only purpose is to destroy organic life.
I'm not sure which theory is more likely to be proved. I would prefer the first (and I release my own code under the BSD licence) but I'm afraid that it only takes one civilisation to construct self-replicating terminators that could take over the galaxy at a significant fraction of the speed of light. Furthermore, since we only have one civilisation to study and our usual response seems to have been "We come in peace, shoot to kill" I'm not desperately confident for the long term future of the human race. After all, it doesn't seem likely that we are the first..
But *why* is it still the square of the distance when I always thought that was just a natural consequence of the increase in volume of a sphere as it's radius increases? If antenna gain makes no difference, then why bother with it at all?
Because although the covered area is much smaller, it still grows quadratically with distance (there simply is no such thing as an exactly parallel beam). The antenna makes a difference in that you get a higher signal in the desired direction to begin with. If your signal is e.g. 25 times as strong in a certain direction, it will remain 25 times as strong even after millions of lightyears. So at a distance where the weak signal would be barely detectable, you still have 25 times the threshold, which should be clearly detectable. Indeed, 25 times the strength means 5 times the reach, due to the inverse scale law.
The Tao of math: The numbers you can count are not the real numbers.
You do realise that sending a message with an Apple product is tantamount to declaring war? Goddammit, did you not see that documentary with the MacBook?
Except that Alpha Centauri's staggeringly advanced "alien" technology has solved this problem long, long ago.
Unfortunately, they have also developed staggeringly advanced spam filters that will dump our message in the "junk" folder.
Set your phasers on "funky"!
I wonder if we are going to get one back: "Can you keep the ^%£$&^$*$&^ noise down!"
Pluto is a planet, it's just one of 5 dwarf planets. So yes, to be completely accurate, they'd either need to ditch Pluto or add Ceres, Haumea, Makemake, and Eris.
All that said, I'm guessing 'ET' woouldn't give two shits about the dwarf planets. He'd see the gas giants, and maybe our 4 inner planets. If they looked really close, they might see some assorted rocky and icy belts, but nothing worth mentioning compared to the other planets.
Of course, part of the idea of dwarf planets is to make them open ended, so you don't need to memorize all of them. The analogy is to mountains: there are lots of mountains, people don't memorize them all, but they're still given special recognition.
Write your representatives! Repeal the 2nd Law of Thermodynamics!
Based on human behavior, we can roughly guess that at least 10% of any/all intelligent receivers will be agressive.
Really want to mess with your head? Try this on for size. Based on human behavior, we can roughly guess that at least 90% of any/all intelligent receivers will believe in some form of supernatural friend in the sky whom runs the whole show. Now how are they going to freak out when a dude in the sky starts talking to them?
See, now slashdotters whom watch too much BSG are worried about fighting the cylons, but the average (and below average) moron on the street is going to be worried about the supernatural implications.
"Science flies us to the moon. Religion flies us into buildings." - Victor Stenger
Our star is in the second generation, so anyone around a first generation star had a head start of a few billion years. They'd have much more difficulty reaching space because they'd have a shortage of heavier elements (most of the ones we have access to come from the collapse of first-generation stars). With self-replicating colonies and a decent ion drive (i.e. stuff we could build with known science and just a bit of engineering effort if we had the political will), it would take around a million years to colonise the entire galaxy. Between the formation of the first planets in this galaxy and the formation of life on Earth there was enough time for a few thousand species to be born, create galaxy-spanning empires, and die out (or become non-corporeal, or go to a different universe, or whatever species do once they've conquered the entire galaxy).
It's also worth noting that the majority of stars in this galaxy are binaries. Life around single stars might be more rare. The tidal forces from the two stars on the crust of a planet in a binary system are likely to increase surface radioactivity and mutation rate, and intelligence would be much more of an advantage in the rapidly changing environment of a planet in an eccentric orbit. It's entirely possible that there are interstellar civilisations around most of the binary stars in the galaxy, completely ignoring us because life around single stars is so unlikely it's not worth investing effort searching for.
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Definitely, sending the same message repeatedly is better than sending multiple messages in different encoding schemes. However:
The Arecibo message was designed to be as easy as possible to decode, it would be possible to do so with just a pencil and paper.
Designed, sure. I recall reading that it was nigh-impenetrable in practice, and it flip-flops between ways of encoding the same data at various points (e.g. it introduces a scheme for writing binary in limited space in the first part, then ditches it in favour of just extending the space in the second) which is hardly conducive to understanding. It should've been edited, then retransmitted. That way it would still stand out, but it would give some clues as to what it's actually meant to say.
No kidding!!! What do you say at this point?
One bit per second is good enough for the Navy...
Yes, but only because they have prearranged short codes for orders that are likely to be given. A message only a handful of characters long can be useful under those circumstances.
Pointless Calculation...
What if they tried to send the exact same information to a neighbor, using Verizon wireless...
As a text message:
Base Pairs in DNA: 3,080,000,000
Total # Characters 6,160,000,000.00
Text Message Limit 160
# Text Messages: 38,500,000.00
Rate per Text Message: $0.20
Cost: $7,700,000.00
Using Verizon's 1.99/MB data rate:
Megabytes Data 770
Cost Per Megabyte $1.99
Total Cost $1,532.30
Mailing a Baggy full of sperm:
44 cents.
Seeing the look on your neighbor's face when she opens her envelope:
priceless
"Can you hear me now?"
Undetectable Steganography? Yep, there's an app fo
Oh, hey! We were about to build a hyperspace bypass through your solar system. But now that we know it's inhabited, we'll reroute that and give you an on-ramp.
Haven't I read this from somewhere before... Except they didn't reroute the hyperspace bypass.
"I am the king of the Romans, and am superior to rules of grammar!"
-Sigismund, Holy Roman Emperor (1368-1437)