SETI, in general stands for the Search for Extra Terrestrial Intelligence. It can also specifically stand for the non profit institute of the same name founded in 1984. Currently the term SETI still refers to a large blanket of efforts to detect alien life, centered around the initiation and detection of communication, most of which is done by radio telescope. It is assumed for numerous reasons that any communication we detect will be in the form of microwaves, although this has been disputed. The work itself is really quite tedious. It basically involves pointing dishes at the sky and constantly moving them around, recording the data stream recieved, and later analyzing it for anomaly. The sky is very, very big, and there is lots and lots of data. You can only imagine the amount of computing power this requires. This led to one of the more interesting features of SETI. Thanks to the advances of the internet and availability of programming recipes, a scientist at berkely designed a program that could be installed on home computers and communicate with the hub recievers to take on some of the processing signals. SETI@home was born. Currently there are over 5 million users that have provided 19 billion hours of computing. Interestingly, this adds up to only the 2nd most powerful supercomputer in the world. On a side note, there is a similar @home program to search for new prime numbers. Thanks to computers we have already discovered many of them. Consequently the undiscovered ones are very large and take an enormous and complex algorithm to test. There is a program that can be installed on the home computer that will recieve a single number and test it. I believe it takes a few days to test a single number, but if your computer finds one you win something like $10,000. Anyway...
We have actually recieved only 1 signal considered universally to be a candidate signal. It is known as the 'wow' signal, because the researcher on duty at the time circled it on the print out and wrote 'wow' on the paper next to it:
Let that be a lesson to be careful what you do and say near the time of a major scientific discovery. The "wow" signal was very short lived, unfortunately, and many subsequent searches of the same area have failed to find anything.
The discovery of said intelligent life is considered by many prominent and respected minds to be an inevitibilty. Enrico Fermi, a very important physicist authored a deceptivily simple paradox entitled "Fermi's Paradox" (go figure). The gist of it goes: "Where is everybody?" Doesn't seem like much of a paradox, does it? Well, what he is really saying is that in all likelyhood, the fact that we managed to evolve combined with the infinitely unimaginable size of the universe pretty much guarantees that there must be life elsewhere in the universe. So why haven't we discovered any?
This discovery is also considered by other prominent minds to be pseudoscience. In fact, writer Michael Chricton criticized several of the major justifications for SETI and used them as a basis to label SETI religion, rather than actual research. Well if Michael Crichton says it....
This leads us to what is commonly known as 'active SETI' For all our attempts to recieve messages we have sent relatively few. They number less than 20 and include the visual message and gold record sent out on the Voyager probes. Incidentally, these probes are still transmitting data from locations outside the solar system. The most famous one is known as the "Arecibo Message", Many of you may know Arecibo as the location of a very large radio telescope in Puerto Rico, also known as "Big Ear", made famous by the movie "Contact" Starring Jody Foster and written by Carl Sagan (thats why it's so good, cause it's scientifically accurate).
The message itself was, well, retarded.
It was transmitted in binary, similar to morse code, but distinguished by a series of 'on' and 'offs' corresponding to 0's and 1's. The total number of bits in the message was a semi prime number, a number that it is the product of two primes. This was so that the data could be grouped into columns and rows, and done so in only 1 way (actually 2, because you can switch the rows and colums). The data should then be imaged, much like pixels, where a 1 would represent white and 0 black (the color was added to this image to distinguish different parts of the message). This is where the image above is obtained.
The top of the message is the first 10 numbers in binary. Then comes the atomic weight of hydrogen and a few other elements. Then is a description of dna, followed by a picture of man (without a head?). Underneath that is a map of our solar system, earth being the 'up' planet, and finally a picture of the Arecibo reciever (upside down?). This retarded image was the result of hours of committe discussion and deliberation. Oh, and did I mention it was sent to a star that won't be there when it arrives?
The title of this blog is "SETI's Paradox", and if you know me you know I love paradoxes. I mostly just wanted to talk about SETI, but I also wanted to discuss the subject of this paradox. Our SETI thus far has been focused on listening, almost to the complete exclusion of anything else. So what if everybody else is only listenening too? That could be a good reason we haven't found anything yet.
Thank You and Good night.
PS:
I had a GREAT 4th of July
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