If Earth is a blue marble, it’s certainly not one you’d want to depend on in the chalk circle. Instead of being a sphere, it’s actually far more irregular (and not just the mountains, duh). Charles Q. Choi lays out lots of oddities about our lumpy planet at SciAm.
Here’s some tidbits:
- Earth is actually an oblate spheroid, bigger at the equator than at the poles.
- Gravity is unevenly distributed around Earth, which looks something like this when you draw it.
- Areas of the crust and mantle are still rising up to a centimeter a year after being crushed beneath the weight of glaciers during the ice age.
I hope that the Earth doesn’t feel self-conscious, though. Because we all have our imperfections. And this lumpy ball of dirt and magma is the only home we have.