Arecibo Message Sent into Space 44 Years Ago Today

The binary transmission with color added to accent its separate parts.

The binary transmission with color added to accent its separate parts.

On November 16th, 1974 a message was sent into space to commemorate the remodeling of the Arecibo radio telescope in Puerto Rico.

Referred to as the Arecibo message, it consisted of 1,679 binary digits and approximately 210 bytes; the message was transmitted towards globular star cluster M13 at a frequency of 2,380 MHz and modulated by shifting the frequency by 10 Hz, with a power of 450 kW. The hope was that an extraterrestrial intelligence might receive and decipher the message.

Those 1,679 bits were arranged into 73 lines of 23 characters each, and formed the image pictured above when translated into graphics, characters, and spaces. 73 lines of 23 characters were used because those are both prime numbers, and may have helped any extraterrestrials decode the message.

The image, from top to bottom, was created to show:

  1. The numbers one through ten (pictured in white).

  2. The atomic numbers of the elements that make up DNA; hydrogen, carbon, nitrogen, oxygen, and phosphorous (pictured in purple).

  3. The formulas for the bases and sugars in the nucleotides of DNA (pictured in green).

  4. The number of nucleotides in DNA, along with a graphic of DNA's double helix structure (pictured in white and blue, respectively).

  5. The figure of a human, the dimensions of an average man, and the human population of Earth (pictured in red, blue and white, and white, respectively).

  6. A graphic of our solar system indicating from which planet the message originated (pictured in yellow).

  7. A graphic of the Arecibo radio telescope and the dimension of its antenna dish (pictured in purple, and white and blue, respectively).

The message was created by Dr. Frank Drake—creator of the Drake equation to determine the likelihood of extraterrestrial life—along with Carl Sagan and a team of scientists.

They projected that the transmission would take 25,000 years to reach M13 and another 25,000 years to return, assuming the message is returned using the same medium of delivery, and thus it was at the time viewed as more of a demonstration of human technological achievement than a real effort to contact extraterrestrials.

After 44 years it remains a mystery as to whether we will receive a response to the message; assuming we haven’t already.



Tobias & Emily Wayland