What’s it actually like to sleep in space? After spending nearly six months aboard the International Space Station, Chris Hadfield says it’s one of the most comfortable parts of life in orbit – no mattress, pillow, or rolling over required.

On GZERO World, Hadfield tells Ian Bremmer what it feels like to sleep in zero gravity and how circling the planet every 90 minutes gave him a new perspective on Earth. After traveling around the world roughly 2,600 times, he says seeing its borders, geography, and immense history from above left him with a deeper sense of our shared humanity – and greater optimism about its future.