Having an opinion on aliens is the one thing Stephen Hawking, Edward Snowden and The Martian author, Andy Weir, all have in common.
Weir, a self-confessed space geek, doesn't believe that they exist on Mars.
He joined us for a chat through Google Hangout and his enthusiasm for space and all it entails, is boundless.
Despite his vast knowledge of the extraterrestrial world, carefully acquired through years of research, he is patient to give a detailed explanation of his beliefs, however out-of-vogue they may seem.
This includes a percolating opinion that Hawking is wasting his time trying to find aliens and that Mars One candidates are all a little...well, let us just say he doesn't compliment them.