Bad Astronomy compiles a list of ten things you don’t know about the Earth. You probably (hopefully?) know a few of these already.
- The Earth is smoother than a billiard ball
- The Earth is an oblate spheroid
- The Earth isn’t an oblate spheroid
- The Earth is not exactly aligned with its geoid
- Jumping into a hole through the Earth is like orbiting it
- The Earth’s interior is hot due to impacts, shrinkage, sinkage, and radioactive decay
- The Earth has at least five natural moons; but not really
- The Earth is getting more massive
- Mt. Everest isn’t the biggest mountain
- Destroying the Earth is hard
Amazingly I did know about the bloggers’ favourite, number 5, thanks to an uploaded clip from an old History Channel programme on gravity. So there.