Edward Snowden pravi, da inteligentnega življenja drugje v vesolju še nismo odkrili, ker vesoljci svoja sporočila šifrirajo. Obdobje razvoja, ko neka civilizacija uporablja nezaščitene kanale za komunikacijo, je namreč po njegovem zelo kratko.
"If you look at encrypted communication, if they are properly encrypted, there is no real way to tell that they are encrypted," Snowden said. "You can't distinguish a properly encrypted communication from random behaviour."
Posnetek celotnega pogovora Neil deGrasse Tysona z Edwardom Snowdnom je na voljo tule: A Conversation with Edward Snowden by StarTalk Radio
Therefore, Snowden continued, as human and alien societies get more sophisticated and move from "open communications" to encrypted communication, the signals being broadcast will quickly stop looking like recognisable signals.
"So if you have an an alien civilization trying to listen for other civilizations," he said, "or our civilization 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."
After that, Snowden said, alien messages would be so encrypted that it would render them unrecognisable, "indistinguishable to us from cosmic microwave background radiation". In that case, humanity would not even realise it had received such communications. (Vir: Edward Snowden: we may never spot space aliens thanks to encryption | The Guardian)