About 300 million years after the Big Bang the first GALAXIES were formed in lots of shapes and sizes. Our galaxy, THE MILKY WAY is one of the oldest - scientists think it was formed about 13 million years ago.
  1. HOW BIG is the Milky Way? (2 ways to answer - give both)
  2. What is "the dark side" of gravity?
  3. How are BLACK HOLES formed?

Disclose.tv - Stephen Hawking: The Story of Everything pt 4/9 Video