- By Brandon Keim
Alien-seeking researchers have designed a new, simple code for sending messages into space. To a reasonably clever alien with math skills and a bit of astronomical training, the messages should be easy to decipher.
As of now, Earthlings spend much more time searching for alien radio messages than broadcasting news of ourselves. We know how to do it, but relatively little attention has been paid to “ensuring that a transmitted message will be understandable to an alien listener,” wrote California Institute of Technology geoscientist Michael Busch and Rachel Reddick, a Stanford University physicist, in a study filed online Friday on arXiv.
According to Busch and Reddick, neither the Arecibo message, beamed at star cluster M13 in 1974, nor the Cosmic Calls sent in 1999 and 2003 were tested for decipherability. So the pair devised their own alien-friendly messaging system: Busch invented the code, and Reddick role-played the part of an alien trying to decode it.
Like the earlier codes, Busch’s used radio to send a string of ones and zeroes. But whereas those messages were meant to be translated into pictures, Busch’s code is supposed to be turned into mathematical equations.
Reddick received the code, minus a chunk at its beginning and fragments throughout its body, as if she’d tuned in late to a signal slightly distorted by its passage through space. Knowing nothing about the code, and using nothing but a pencil, paper and a computer’s search-and-replace function, she decoded its start: descriptions of gravity and atomic mass ratios, which are “dimensionless numbers that should be universally recognized.” Once Reddick worked those out, the rest of the message — descriptions of atoms, chemical formulas for the elements required for life on Earth, and details of our solar system — came quickly.
The code does presume that alien listeners have “at least an equivalent knowledge of mathematics, astronomy, and physics,” wrote Busch and Reddick. But even five undergraduate students needed only an hour to figure out a few of Busch’s mathematical and grammatical basics, so it can’t be that hard.
For now, it seems unlikely that the code will actually be sent into space. The Search for Extraterrestrial Intelligence runs on a shoestring budget, and doesn’t directly receive national funding. But if it’s this cheap and easy to talk to aliens, perhaps humanity should try more often.