The Arecibo Message Was Our First Attempt At Talking To Aliens

How long have we been trying to talk to aliens? Well, really only since 1974, the year we sent the first message into interstellar space. This was the Arecibo Message.

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Are You There, Aliens? It's Us, Earth.

In 1974, astrophysicist Frank Drake had an idea. Basically, Drake wanted to send a message to aliens. This makes sense, as he's the same guy behind the Drake equation used to estimate the odds of finding intelligent life beyond our planet. Drake enlisted Carl Sagan to write and format the message, and recruited some others to get the project rolling. The signal they put together was named the Arecibo message, because it was to be broadcast by the Arecibo radio telescope in Puerto Rico. We know what you're thinking, and no, the message doesn't start with "Dear aliens". Instead, it relies heavily on mathematical schemes the scientists hope an alien civilization would be able to decode. According to SETI, "The transmission consisted of a simple, pictorial message, aimed at our putative cosmic companions in the globular star cluster M13. This cluster is roughly 21,000 light-years from us, near the edge of the Milky Way galaxy, and contains approximately a third of a million stars."

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What Did The Message Say?

The Arecibo message, as Mental Floss reports, "consisted of just 1,679 binary digits (1's and 0's). The digits were broadcast one per second, on November 16, 1974." We can see the message as a colorized version of blocks, but using binary encoding, the message contained this information:

  • the numbers one (1) through ten (10)

  • the atomic numbers of the elements hydrogen, carbon, nitrogen, oxygen, and phosphorus, which make up deoxyribonucleic acid (DNA)

  • the formulas for the sugars and bases in the nucleotides of DNA

  • the number of nucleotides in DNA, and a graphic of the double helix structure of DNA

  • a graphic figure of a man, the dimension (physical height) of an average man, and the human population of Earth

  • a graphic of Earth's solar system

  • a graphic of the Arecibo radio telescope and the dimension (the physical diameter) of the transmitting antenna dish

Don't Hold Your Breath For A Reply

If aliens ever do receive the Arecibo message, it'll be in about 25,000 years. And if they choose to respond to us, we wouldn't get that message in another 25,000 years. So yeah, don't wait up for it.

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Written by Curiosity Staff January 13, 2017

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