In 1974, from the Arecibo telescope in Puerto Rico, USA, a message in the form of radio waves was broadcast out in the universe, specifically, aimed at the center of the galaxy M13. 47 years ago, We marked the first-ever intentional attempt to reach out further than the humans on our planet Earth. Designed by Frank Drake, the creator of the Drake equation, and Carl Sagan, a well-known science communicator, the Arecibo message contains many intricate considerations that we will be exploring in this article.
Purpose of the message
Despite the grandeur of the story around it, the message which was beamed into space never held any intentions or hoped actually to reach aliens and establish communication. Instead, it was more symbolic in nature, a demonstration of human accomplishments and worth. A way of saying, “if we wanted, we could.”
Furthermore, the timeframe in which the message would or could be read by aliens is inconsistent. Indeed, the center of the globular cluster M13 at which the Arecibo message was aimed is located around 25,000 light-years from Earth. Since the message travels at the speed of light (300,000 km/s), it would only arrive in 25,000 years. This will lead to some location mismatches, making the message unlikely to reach the core of M13 precisely since it will most certainly have moved due to its orbit around its galactic center.
Format of the message
The true purpose can also be seen in the format of the Arecibo message. Indeed, the image contained 1679 binary digits, which correspond to approximately 210 bytes. This yields a resolution too low to be intercepted and understood by extraterrestrials realistically; there is too little information for one to understand the true message and intention behind the elements in the image. This demonstrates that no genuine and thorough attempt was made to establish extraterrestrial contact.
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In the form of bytes – 0s and 1s – the Arecibo message was broadcast with frequency shifting. More specifically, the image was encoded in a sequence of bytes corresponding to a pixel on the image. Then, at a frequency of 2,380 MHz, the bits were emitted by shifting this base frequency by 10 Hz at a rate of 10 bits per second. Thus, if we calculate how long the message took to broadcast (1679 bytes and 10 of them per second), we obtain a result of about 160 seconds which is a little less than 3 minutes in total.
Finally, some thought was also put into the reconstruction of the image from the bit sequence. Indeed, the total number of bytes/pixels – 1679 – is a semi-prime number. This means that it only has one pair of divisors (two prime numbers) other than one and itself. Here 23 and 73 make 1679. This means that there is only one way to arrange the transmitted sequence of bits back into the form of a rectangle (of 23 by 73 pixels). All other formats would produce an unintelligible string of bits.
Content of the message
The Arecibo message consisted of 10 main sections, which each conveyed a different aspect of life on Earth and the human species. First, at the top of the broadcasted image, we have a concept that is fundamental to society: how we count. In the first four columns are communicated the numbers 1 to 10 in binary notation.
The fourth row indicates where the notation for each consecutive number begins, and the three above rows contain the said binary digits that are to be read from top to bottom. The binary representation of numbers 1 to 7 each occupies a column of 3 bits. Since the binary notation for 8, 9, and 10 occupies more than 3 bits, their representation is spread over two columns.
Secondly, under the image of the binary digits, we find DNA elements, the basis of life on Earth – what encodes us as humans. This section thus contains a message conveying the chemical elements present in our DNA. To communicate them, we once have a binary notation in columns that indicate the respective atomic numbers of the elements composing DNA – 1 for Hydrogen, 6 for Carbon, 7 for Nitrogen, 8 for Oxygen, and 15 for Phosphorus.
The third section is also related to DNA but contains the complete chemical formulae that stem from the previously depicted elements and compose DNA nucleotides. They are displayed under the forms of sequences or groups which reuse the same notation for the previously represented chemical elements.
The Arecibo continues to zoom out on human biology and, in the fourth section, depicts a DNA double helix. Notice how the message is going from small to big. The double helix is the shape in which the double-stranded DNA which makes up humans is naturally found.
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Furthermore, the depiction of the double helix also contains a vertical bar in the middle which is a binary representation of the number of nucleotide base pairs that can be found in the human genome. As the message was crafted in 1974, the number is off, conveying 4.3 billion instead of the 3.2 billion we know of today.
If we zoom out from the human scale, we arrive at the scale of planets depicted here in the sixth section, specifically the Solar System in the form of yellow dots. It is interesting to note that as the message was crafted in 1974, Pluto was depicted as still classified as a planet. An interesting view into the past!
To indicate the planet’s sizes (of course, the scale is rather empirical), larger planets are depicted with more dots than smaller ones. Finally, it is to note that planet Earth is emphasized (shifted upwards) to indicate that this is where the message originates from. Furthermore, the human being depicted in the previous section figures right above planet Earth, another hint!
Finally, the seventh and last section contains a telescope, notably the Arecibo Telescope from which the message was broadcasted.
Insights and considerations concerning alien communication
The Arecibo message is one of the many attempts that were and are made to either establish Alien communication or evaluate it. Indeed, the SETI Institute – Search for extraterrestrial intelligence – has research oriented towards the multiple consideration around extraterrestrial intelligence. Examples of some of their endeavors are monitoring the electromagnetic activity of outer space, investigating the condition necessary to live, or studying techno-signatures, which are the markers that an area in space would be recognized by if an intelligent species populated it.
We are a human living in earth one of the best habitable planet of the solar system orbiting sun and want to protect our planet from any future harm and we want peace