Remembering Stephen Hawking, a renowned physicist and ambassador of science. His theories unlocked a universe of possibilities that we & the world are exploring. May you keep flying like superman in microgravity, as you said to astronauts on the International Space Station in 2014. Astronauts Rick Mastracchio and Koichi Wakata aboard the International Space Station spoke with Professor Hawking during their mission in 2014. These excerpts courtesy of Arrow Media. More: https://www.nasa.gov/conten