Is anybody out there? angello   Are we alone in the universe? People have tried to answer this question since ancient times, but the question has seldom been sent up into space. To give a scientific answer, the SETI programme was started in the 1950's (Search for Extraterrestrial Intelligence). The programme was based on the book written by the investigator Carl Sagan and it became famous thanks to the film “Contact”. Investigators looked for an appropriate electromagnetic frequency for sending messages. As hydrogen is the most common element in the universe (it's emitted at 1,420 megahertz), they thought that extraterrestrial beings might use that.

Once they had found the frequency of reception, in 1974 Carl Sagan and some other famous brains sent out the message in the picture from Arecibo radio telescope, the biggest in the world. At first, it was a secret programme. The people in charge of it were embarrassed by it as it gave the impression that they were looking for extraterrestrial beings and, maybe, people would be against sending the message as it could attract extraterrestrial attackers. It's improbable extraterrestrial civilisations will pick up the message sent from Arecibo. They sent the message to a group of stars called Messier, which are 25,000 light years away, and, at the speed of light, that will take 51,974 years to reach them. The message, written in binary, contained this information: The solar system, numbers up to ten, atomic numbers, helicoid DNA, an image of average human height and a drawing of the Arecibo telescope. And is somebody does receive it, what will the extraterrestrials think of a message that looks like it's been written by a child?