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CUTTING

away, transmitted at a radio frequency of 452.13
Our experts examine the EDGE MHz. Within a month, he had received 66 correct
hottest new research solutions, about half of which were independent
instances of the message having been cracked – the
other half were based on help provided on public
Citizen scientists could online discussion forums.
So what did this dummy SETI transmission
consist of? The first clue in decoding this message
decode an alien message comes from realising that the total number of bits
– 1,902,341 – is the number that results from
multiplying three prime numbers: seven, 359 and
The SETI Decrypt Challenge asked social media
756. Thus there are seven pages of data, each made
user to interpret an ‘extraterrestrial’ signal up of a grid of binary numbers 359 wide by 757 tall.
The first page contains just a frame of 1s to specify
the size of the other six sheets. Page two defines the
number system by counting up to 756, and page
three lists the first 757 prime numbers – these
establish that the message speaks in binary. Page
four is an image of a sine function, just like the
transmitted radio wave, with two numbers denoting
the universal physical parameters of the Plank
length and the Plank time. Taken together, this tells

“Any effort to
decode a received

alien message may
LQGHHG!EHQH"W!IURP!

the collaborative
he search for extraterrestrial Þ The final four pages
intelligence (SETI) deals with the of Heller’s message efforts of amateurs”
possible receipt of a message transmitted – all vital information
about the sender
Tfrom an alien race and attempts to you the alien civilization knows that the Solar
contact them with broadcasts of our own. But the System is 50 lightyears from them; this is a direct
key question is: would we be able to decode and message intended specifically for us. Page five is an
understand any message we receive from the image of the extraterrestrial species, with a header
stars? Or, visa versa, how should we construct containing the information 2.45m and 180 years,
our own messages to make them easily their average height and lifespan. Page six is a
understandable to extraterrestrial civilisations? picture of the transmitting radio dish, and the final
To explore this, René Heller at the Max image is of the alien homeworld with the number
Planck Institute for Solar System Research six billion years, the age of their planetary system.
in Germany ran an experiment – the SETI Heller says that the lesson learned from this
Decrypt Challenge. He constructed a test test-run is that any effort to decode a received alien
interstellar message and released it to the message may indeed benefit from the collaborative
internet to see if crowd-sourcing the solution efforts of amateurs around the world, rather than a
could be effective. select few experts in a decryption team. And it’s not
The message that Heller composed consisted just a numbers game; without any prior knowledge
of a sequence of almost two million bits (1s of the psychology or motivations of an alien race the
and 0s) the format that can be transmitted by chances of successfully understanding a message are
a high-powered radio dish. It was also about a LEWIS DARTNELL is an greatly improved by involving people from a range
thousand times larger than the ‘Arecibo message’ astrobiology researcher of cultural and educational backgrounds.
transmitted towards globular cluster M13 from at the University of
Westminster and the
the Arecibo radio telescope in Puerto Rico in 1974.
author of The Knowledge: LEWIS DARTNELL was reading… Decryption of
Heller posted this message on social media,
RENÉ HELLER/SETI inviting anyone interested to have a go at from Scratch (www.the- Power of Social Media – The SETI Decrypt Challenge
Messages from Extraterrestrial Intelligence Using the
How to Rebuild our World
deciphering it. He explained the scenario that this
by René Heller
knowledge.org)
Read it online at https://arxiv.org/abs/1706.00653
signal had been received from a star 50 lightyears
skyatnightmagazine.com 2017