For 65 years, astronomers in search of alien life have wrestled with the question known as Fermi’s Paradox: where are all the other intelligent beings out there? But while researchers haven’t heard a peep from any spacefaring species, it’s possible that they just don’t know how to decrypt the message.
On a recent episode of astrophysicist Neil deGrasse Tyson’s podcast, StarTalk, U.S. government whistleblower Edward Snowden suggested that aliens might have such strong encryption techniques that human scientists may not even recognize their messages for what they are.
“If you look at encrypted communication, if they are properly encrypted, there is no real way to tell that they are encrypted,” Snowden tells Tyson about 30 minutes into the podcast. “You can’t distinguish a properly encrypted communication from random behaviour.”
The problem, Snowden says, is that there might be just a short period of time in the lifespan of a sentient civilization where it doesn’t encrypt its broadcasts. While scientists have sent out probes and signals that attempt to communicate an intentional message, like the Voyager Mission and the Arecibo Message, programs like the SETI Institute might be assuming that alien species are also sending open messages, Nicky Woolf reports for The Guardian. But if, as Snowden suggests, any possible aliens do use some form of encryption, scientists may not even recognize their messages for what they are.
"When we think about everything we're hearing from our satellites, or everything they're hearing from our civilization, if there are indeed aliens out there, all of their communications are encrypted by default,” Snowden tells Tyson. “So what we're hearing — which is actually an alien television show or a phone call or a message between their planet and their own GPS constellation, whatever it happens to be — is indistinguishable to us from cosmic microwave background radiation."
Snowden isn’t the first to suggest that scientists have simply not yet recognized alien broadcasts for what they are. As David H. Bailey and Jonathan M. Borwein write for The Huffington Post, the SETI Institute’s mission assumes that if extraterrestrial beings were to send us a message, they would do so in an obvious way that our technology could detect.
Or, it’s possible that alien civilizations used to exist, but were killed by a cosmic mishap or destroyed by their own hands. Recently, a group of scientists published a study that’s something of SETI’s dark reflection: what National Geographic's Mark Strauss calls the "SEETI study," or the “Search for Extinct Extraterrestrial Intelligence.” The study authors posit that an alien apocalypse could leave behind evidence that astronomers could detect with advanced telescopes, such as evidence of nuclear fallout or biological weapons gone awry. The remains of organic material consumed by nanotechnology – known as a “grey goo” apocalypse – could be detectable for thousands of years.
“In time, the first evidence of extraterrestrial intelligence may come to us from the remains of less prudent civilizations,” the study’s authors write. “In doing so, such information will bring us not only knowledge, but wisdom.”