We were super-excited to share some of your questions with former astronaut Commander Chris Hadfield. Commander Hadfield has flown in space 3 times - totalling 166 days! He has been Commander of the International Space Station and has performed two space-walks!
He was delighted to answer your questions. What can you learn from his answers? How can these help you answer our big questions already on the Hub?
What do you think now, after hearing Commander Hadfield's answers? Add your comments below!