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Comments: 249 +- Science: After 35 Years, Another Message Sent From Arecibo on Sunday November 22, @10:11PM
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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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And it was (Score:5, Insightful)
Re:And it was (Score:5, Funny)
Send More Funding
I'm sure they won't be waiting any longer than usual for a response.
Parent
Re:Representation of the solar system in the messa (Score:4, Insightful)
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.
Parent
Re:And it was (Score:5, Funny)
Parent
Re:And it was (Score:5, Funny)
No, it was - "Kids and grown ups love it so, the happy world of Arecibo"
Parent
We are here! Come and get us! (Score:5, Funny)
We are very tasty snacks! Here, have our DNA, and grow some appetizers for the long journey!
Re: (Score:2)
Since ET already gets all our TV transmissions, plus cell phones and wifi, I don't think this one will make much difference.
Practical joke (Score:5, Insightful)
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.
Re:Practical joke (Score:5, Funny)
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.
But if they do figure it out, we'll get a message a century from now: "Delicious! Do you have any other recipes?"
Parent
Re:Practical joke (Score:4, Insightful)
>>But if they do figure it out, we'll get a message a century from now: "Delicious! Do you have any other recipes?"
Sadly, people rarely stop to wonder if the messages we're sending into outer space are a good idea. Aliens with a good grasp of game theory might just very well decide to drop a meteor onto any planet they find broadcasting into outer space. You know... just to be sure.
I actually find it sort of thoughtless that people like this are taking the entire fate of the world into their hands. Dramatic? Not so much, if you really stop to think about it.
Parent
Re:Practical joke (Score:4, Interesting)
Aliens with a good grasp of game theory might just very well decide to drop a meteor onto any planet they find broadcasting into outer space
If by 'good' you mean 'incredibly poor,' then yes. The response that game theory would dictate to that kind of attack would be a similar (or greater) response. The only way in which a near-C mass[1] attack would be a good plan would be if you could guarantee species annihilation in the first strike. Given that this signal is for starts 100ly away, you'd have to be able to guarantee that, within the next 100 years[2], we would not have any off-planet colonies that would be able to launch a counter attack.
You'd also have to make sure that there was no evidence of it that was observable from other star systems. The collision would be detectable a long way away, and you'd have to hope that no one else saw it and decided that the galaxy would be better off without a belligerent species like yours in it.
[2] It would have to be near-C or we'd see it coming and be able to intercept it, and also know who to shoot back at before it got here even if we couldn't destroy it in time.
[1] Assuming a straight-line projectile. In practice, you'd want to slingshot it around a different star to make it less obvious that you were the originator.
Parent
Re: (Score:3, Funny)
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.
The message (Score:5, Funny)
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.
Ok really? (Score:3, Insightful)
Re: (Score:3, Interesting)
Sure, although on the other hand there's only so many ways we could be able to detect any eventual technological civilisation, so we might as well try them. I mean think about it, optical systems aren't yet able to resolve a body the size of Earth even if it was around a nearby star, and our probes might find basic life on Mars, in Europe or on Titan, but even if they do that'll be some microbiology crap. If there's some dudes (or super smart land-squids) out there in the sky who mastered electricity the on
Re: (Score:3, Funny)
So why not spend research money doing things that we know are going to work.
"If we knew what we were doing, it wouldn't be called research, would it?"
- Albert Einstein
Yo astronomers, I'm really happy for ya... (Score:5, Funny)
Re:Yo astronomers, I'm really happy for ya... (Score:5, Funny)
No, this is the real reply. [nasa.gov]
Parent
Rickroll (Score:5, Funny)
We could have rickrolled them so they could get a taste of our culture!
The message assumes prior knowledge of our world (Score:3, Interesting)
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.
The message was so lame (Score:4, Insightful)
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.
Re:The message was so lame (Score:5, Funny)
[_] At our nearest stellar neighbour, Soviet Centaurans serve YOU. (yum yum thx 4 gene seq bzzzt!)
[_] Your call is important to us. Please stay on the line. Your call is important to us. Please stay
[_] What? Can you hear me now? What? Frakking Aldebaran Telephone and Telecommunications! Get me a Droid!
[_] Get the base ships ready to jump! We've found the 13th colony!
[_] Oh shit. Spaceballs! Oh well, there goes the galaxy
[_] What, is your planet still there? The highway goes through next wee, you know!
[_] The
[_] The borg collective are pissed off at how you've portrayed them. They'll be in your area soon to "discuss it." BTW, we're calling first dibs on your planet.
[_] Sorry, we don't want any illegal aliens in the neighborhood. Please go to another quadrant or we'll have to report you.
[_] Why did the zhicvben cross the whowde? To get to the other side! Thank you, thank you. I'm here all diurnal-periods-times-7. Try the phizch.
[_] That is the most odious and obscene collection of insults and violations of universal taboos any alien race has ever sent our way. Prepare to die, earth scum! We will be avenged!
Let's hope that either they're not there, or they can't hear us if they are, or if they can hear us, they can't reach us, because the odds are that what we'll have is a failure to communicate.
we can't even communicate properly between spouses - it's an incredible conceit to think we could get it right first time with an alien species, and not break any taboo, or accidently insult them ... of that they'd be friendly.
Survival of the fittest means that the predators get to the top of the heap. Don't invite predators unless you *know* that you're better able to defend yourself than they are.
Parent
You did WHAT?!? (Score:3, Funny)
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?
Again? (Score:4, Funny)
I wonder if we are going to get one back: "Can you keep the ^%£$&^$*$&^ noise down!"
The ad reborn (Score:3, Funny)
Re:Wishful thinking (Score:5, Insightful)
Parent
Re:Wishful thinking (Score:5, Funny)
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.
Parent
Re:Wishful thinking (Score:4, Funny)
Parent
Re:Wishful thinking (Score:5, Informative)
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
Parent
Re:Wishful thinking (Score:5, Informative)
Parent
Re:Wishful thinking (Score:5, Interesting)
Actually I believe calculations have been done which show that two Arecibo type telescopes could communicate across the galaxy.
Parent
Re:Wishful thinking (Score:4, Funny)
Not in my lifetime.
Parent
Re:Wishful thinking (Score:4, Funny)
Not in my lifetime.
But maybe mine. I plan on living to be at least 500, hopefully more. So far, so good.
Parent
Re: (Score:2)
Re: (Score:3, Funny)
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.
Re:Wishful thinking (Score:5, Informative)
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.
Parent
Re: (Score:3, Interesting)
One bit per second is good enough for the Navy...
Re: (Score:3, Insightful)
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.
Re:Wishful thinking (Score:5, Insightful)
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.
Parent
Re: (Score:3, Interesting)
In the science fiction story "Dragons Egg" by Robert L Forward [wikipedia.org] (who was incidentally a physics professor and described the book as "a textbook on neutron star physics disguised as
Re:Wishful thinking (Score:4, Interesting)
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.
Parent
Re:Wishful thinking (Score:5, Interesting)
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
Parent
Re:Wishful thinking (Score:5, Informative)
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.
Parent
Re:Just don't take any calls (Score:5, Funny)
Parent
Re:Just don't take any calls (Score:5, Informative)
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
Parent
Re: (Score:3, Informative)
But they did use an iPhone.
Re:iPhone? (Score:4, Funny)
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> ;)
Parent
Re: (Score:3, Insightful)
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.
Re:Dangerous (Score:5, Interesting)
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.
Parent
Re: (Score:3, Informative)
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 f