Watch | US whistleblower Snowden makes Twitter debut

Former U.S. National Security Agency contractor Edward Snowden, who leaked details about the U.S. government's mass surveillance programs, made a debut on Twitter with his first tweet reading “Can you hear me now?”. He made the social networking account from exile in Russia on Tuesday, quickly pulling in more than 300,000 followers. But he was following just one Twitter account: his former employer, the NSA.

So far, Snowden has tweeted with prominent astrophysicist Neil deGrasse Tyson about the discovery of water on Mars and revealed what he's been up to - keeping busy with his work for the Freedom of the Press Foundation, while 'still finding time for cat pictures'.