The science of Close Encounters: could we use music to talk to aliens? 

Golden Record: Greetings to the Universe contained pictures of life on Earth - such as a woman in a supermarket - as well as music that reflected the diversity of humankind’s creative capabilities. Bach was on there, along with Mozart, Beethoven and Stravinsky, as well as Azerbaijani folk music and Chuck Berry - a controversial choice at the time as some deemed his song Johnny B Goode to be “adolescent”. (Carl Sagan, the Cornell University academic who chaired the record’s creation, argued that there were “a lot of adolescents on the planet”.)

The discs also came with a diagram of how to play them, in the hope that extraterrestrial life might come across the Voyager spacecraft and discover the record. Two years ago, the contents were uploaded online, so all of humankind could listen to them, too. 

In 2008, Nasa beamed a Beatles song towards the North star, but again, this was more for human benefit - a means of celebration of the Beatles' and Nasa's shared anniversaries - than for any aliens.

A couple of years later, scientists from SETI (Search for Extraterrestrial Intelligence) Institute, explained at a conference that human art and music would be of far greater interest to alien life than maths or physics, which have previously been used to try and contact aliens.

Douglas Vakoch, the director of interstellar message composition at SETI, said at the time: “If they’re so advanced, we probably can’t teach them about science, but we can tell them what it’s like to be at this precarious point where we don’t know if we’re going to continue as a species.”

But Katz believes that using the fundamentals of mathematics to communicate with aliens is still a better strategy. “[Music] tends to be 'tacked on' to other kinds of messages that represent more fundamental information about the universe and our place in it,” he says. The laws of physics and maths don’t vary between different points of the universe, but the laws of music do. As Katz explains: “There's no particular reason to think that, say, a melody in a major key would be interpretable or pleasant for an alien. The major scales is not even universal across human cultures.”

Bearing scales in mind, the chances of the aliens using exactly the same 12-note chromatic - as they do in Close Encounters of the Third Kind - is extremely unlikely. “It would be extremely far-fetched for extraterrestrials to coincidentally stumble across the same pitch collections, using the same 12-note chromatic,” says Katz.  

Say, however, that our music was heard by aliens and they managed to make sense of its scale, what could we expect to hear back? Spielberg’s symphony isn’t so unrealistic - theoretically speaking, at least: “We often repeat melodies or harmonies more than once, but alter them in some way on the repetitions,” says Katz. “So maybe if we sent a particular kind of melody or harmonic sequence into space, an alien that 'understands' human music could send back a slightly altered repetition to us to show understanding.”

After that, it’s just a case of waiting to see if they want to invade our planet and turn us into slaves, or not.

Related Topics

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