On Friday, Neil deGrasse Tyson welcomed Edward Snowden to his StarTalk podcast. Along with the usual conversations about privacy and government, Snowden had another important warning to provide: encryption may hurt our abilities to see, or be seen by, extraterrestrials.
Speaking to deGrasse Tyson from Russia, Snowden explained that the current need for data encryption may not be doing us many favours -- at least in the cosmic sense. He said:
"If you look at encrypted communication, if they are properly encrypted, there is no real way to tell that they are encrypted. You can't distinguish a properly encrypted communication from random behaviour...
"So if you have an an alien civilisation trying to listen for other civilizations or our civilisation trying to listen for aliens, there's only one small period in the development of their society when all their communication will be sent via the most primitive and most unprotected means."
He also pointed out that properly encrypted alien signals could also be "indistinguishable to us from cosmic microwave background radiation". But deGrasse Tyson has a witty retort to that particular warning: "Only if they have the same security problems as us." Funny, because it's true.