| A | B |
|---|
| cosmology | study of the origin, structure, future of universe |
| Big Bang Theory is that | universe began with tremendous explosion 13.7 billion years ago |
| Big Bang caused | universe to expand in all directions |
| rotation | spinning of a planet on its own axis |
| rotation is like a | spinning top toy or Beyblade |
| orbit | path a planet follows as it travels |
| orbit is like a | road around a star or other planet |
| revolution | one complete trip along an orbit |
| revolution is like a | the running on the road, going all the way around |
