Image from time.com: Stephen Hawking outside DAMTP, Department of Applied Mathematics and Theoretical Physics, Cambridge. Jason Bye / PBS
Astronomer Michael Brown discusses the solar system's bodies and his role in the demotion of Pluto from planet to dwarf planet.
National Geographic - Solar System 101
How was our solar system born? Join scientists as they embark on a journey into the mesmerizing mysteries of space. Hear their expert theories, then decide for yourself.