THE FIRST MESSAGE

The first time humans deliberately sent a message to any potential alien civilisations was in 1974, in the form of a coded radio postcard. Called the Arecibo message, this attempted to explain humanity, just like the Voyager Golden Record. In an attempt to choose a language that would be easiest for extraterrestrials to decipher, binary code was used. Using this code, the receiver can reproduce the grid, with the ones and zeros of the binary code symbolising dark and light squares.

When pieced together correctly, the shape of the human figure and the number of people on Earth at the time would be produced, as well as other information. The message was broadcast from the Arecibo Observatory in Puerto Rico and also included details about maths, DNA and the Solar System. The Arecibo Observatory was the largest radio telescope in the world at the time the message was sent. When transmitted, the radio message was directed at star cluster Messier 13.