Chris Hadfield

Chris Austin Hadfield, OOnt CD, (born August 29, 1959) is a Canadian retired astronaut. He was the first Canadian to walk in space. He has flown on two space shuttle missions and has also served as commander of the International Space Station which made him the first Canadian to serve as commander of the International Space Station when he lead Expedition 35 after launch on 19 December 2012. He was previously a Royal Canadian Air Force fighter pilot. 
Forbes described Hadfield as "perhaps the most social media savvy astronaut ever to leave Earth" with an audience all over the internet including over 2,000,000 Twitter followers, over 600,000 Facebook fans, one of the top Reddit AmA threads of all time and a popular Tumblr blog.
Hadfield wrote a memoir titled "An Astronaut's Guide to Life on Earth" and published it in 2013. The book became a New York Times bestseller and was the bestselling book in Canada on a Canadian subject.