The EISCAT antenna in Tromsø, Norway is 32 metres high

In a bid to talk to aliens, we’re beaming some mathematical music into space. The transmission will travel over 70 trillion miles to one of Earth’s nearest habitable planets in the hope of reaching intelligent extraterrestrials.

Thirty-three clips of ten seconds each will be sent from a huge 32-metre antenna nestled in snowy Tromsø in the north of Norway, to coincide with Sónar Festival’s 25th year anniversary.

If the clips do end up reaching by any intelligent extraterrestrial life, we could receive a response in about 25 years. Three separate transmissions were sent out on October 16, 17 and 18 from the EISCAT (European Incoherent SCATter Scientific Association) antenna, which has a peak power of 1.5 megawatts. Repeating the message means life out there could still piece together the whole transmission if bits are lost along the way.

The actual transmission sounds nothing like our idea of a melody. The music was encoded in binary code along with instructions, also in binary, on how to decode it. “You cannot hope that aliens will understand MP3 technology,” says Ignasi Ribas, astronomer and director of the Institute of Space Studies of Catalonia (IEEC)

The zeroes and ones in the binary code each correlate to a frequency. “The information was encoded by jumping back and forth from these two frequencies at about 930 megahertz,” says Ribas. The tutorial was sent at a speed of 62.5 to 500 bits per second so it’s less likely to distort. “The frequency and speed of the transmission is low enough so if any information is lost due to interference during its trip the music will still be played without too much static.”

The transmission itself contains a tutorial in how to decode it. “You cannot hope that aliens will understand MP3 technology,” Ribas says. If they use the instructions, then the music could be potentially be played by anyone around to hear it.

The tutorial, put together by METI International, a research organisation dedicated to Messaging Extraterrestrial Intelligence, explains what sound waves are. The binary reflects the frequency and length of waves patterns. “They should know how to pull out all the different frequency information,” Ribas says.

Among the artists who recorded pieces for transmission were Autechre, Richie Hawtin, Carsten Nicolai, Modeselektor, Laurent Garnier, Holly Herndon, Matmos, Jean Michel Jarre, Nina Kraviz, The Black Madonna, Kate Tempest, Kode 9, Laurel Halo and Daito Manabe.

The 32-metre antenna is located at the EISCAT facility in Ramfjordmoen, near Tromsø, Norway

It was down to Ribas to choose the transmission target. Out of a possible 4,000 exoplanets, 13 of which are now classed as potentially habitable, he chose Luyten’s Star B because of its distance and similarity to Earth. “”We don’t know whether there is life on the surface of that planet or whether it has evolved to become complex and eventually intelligent, so there are many ‘ifs’ here.”

Luyten’s Star B is 12.4 light years away from Earth, making it part of our immediate solar neighbourhood. It’s three times larger than our planet, but the cool red dwarf star it orbits is about one third of the size and much cooler than our Sun, just 3000 degrees kelvin compared to our Sun’s 5500. Since its sun is so much smaller, the duration of a year on Luyten’s Star B is equivalent to just 19 Earth days “Their star produces a lot less energy – so the planet has to be closer to it to be warm enough, which means time goes faster,” Ribas says.

The ideal target would have been Proxima Centauri, the exoplanet just 4.2 light years away from us that could potentially support life. “Proxima Centauri is only visible from the Southern Hemisphere and we didn’t have a powerful antenna there,” Ribas explains. “So we had to be content aiming for the north of the sky.”

Ribas is doubtful that we will get a reply, but says that doesn’t mean it’s not worth trying. “Unless we try we will never start communicating,” he says. “This is an experiment that says ‘Hello, we are here; so if you want to respond we will be listening’.”

He references the zoo hypothesis in which animals communicate to each other, but unless they communicate directly to humans we will never regard them as communicative as us. “Maybe the universe is the same. Maybe there are lots of beings talking to each other but never making an effort to talk to anyone else,” Ribas says.

“If we did get a response, it would be pretty amazing,” he says. And it could be a lesson in humility. “A response would raise a global conscience to humanity. We always think we are so important and our problems are so big. It would be interesting for society to understand we are not alone, and there are other intelligent beings out there with their own problems.”

A second batch of transmissions is scheduled for April 2018, and there is an open call for original compositions. Sónar will select 3 to form part of the next transmission.

This content was originally published here.