http://www.cropcircleresearch.com/articles/arecibo.html

(Crop circle formation) resembled a radio transmission that SETI (the Search for Extra-Terrestrial Intelligence) sent from the Arecibo radio telescope in 1974. This latter formation will be examined in this article, in which I hope to not only describe and explain the original transmission, but also to examine and decode a number of significant changes occurring in the crop formation.
After speaking to witnesses, it would appear that the 'Arecibo' formation was created on August 20th.



Why 1679 digits?
The reason for this is down to mathematics. 1679 is the unique product of two prime numbers; 23 and 73. Any sufficiently intelligent lifeform would no doubt look for unique, universal constructs - such as prime numbers, chemical element frequencies and binary digits. Don't forget that because we could be trying to communicate with an intelligence completely different to our own, we cannot talk in terms of 'human' systems, such as centimetres, feet, decimal numbers etc.


Decoding the original message
The original message was comprised of several 'sections', each depicting a particular aspect of 'our civilisation'.

At the top are binary representations of the numbers one through to ten, interestingly showing the numbers eight, nine and ten as two columns. This shows anyone decoding the message that we can specify that numbers too large to be written on a single line can be 'carried over'.

The next section contains the binary values 1,6,7,8 and 15 which indicate the atomic numbers of the primary elements for life on Earth; Hydrogen, Carbon, Nitrogen, Oxygen and Phosphorus respectively.
The larger section of three rows, represents the formulas for the sugars and bases in the nucleotides of DNA. Beneath this is a graphical representation of our DNA 'double helix' either side of a 'straight vertical bar' which indicates the number of nucleotides in DNA.

Directly below the DNA double helix is a small representation of us - humans - with a body and two arms and two legs (like a little stick man). On the left is a binary value of the population of Earth. This can be calculated as roughly 4.29 billion, which is roughly the population of the world, back in 1974. On the right of the humanoid form is a binary code for the height of humans. Because we cannot communicate in 'human' measurements (such as feet and inches) the height is represented in 'wavelength units'. As mentioned earlier, the actual message was transmitted on 2380MHz. To convert this into a wavelength we divide into 300, to obtain a wavelength in metres. 300/2380 = 0.12605042m = 12.6cm. This is our 'wavelength unit'.

From the code for the height of a human, we can see that the value is 1110 in binary, or 14 in decimal. If we multiply 14 by our wavelength unit (12.6) we get 176.4cm, or roughly 5'9" - the average height of humans.
The next section is a simplified representation of our Solar System - where we live. It shows the sun and nine planets, roughly representative of size. By moving the third planet up slightly it highlights that something is significant about the third planet from the sun - Earth.

The last section depicts the origin of the message itself - the Arecibo radio telescope, which is the curved structure. Underneath this, as the last two lines of the message, is another binary number. This time it's 100101111110 (split onto two lines in the centre) and equates to 2430 in decimal. Again, using our universal 'wavelength units' we get 2430*12.6cm which is 30618cm - or approx 1000', the diameter of the Arecibo radio dish.