if the Earth were shrunk down to the size of a billiard ball, it would actually be smoother than one.
But there the similarity ends:
Since the Earth spins, there is a force outward that is a maximum at the Earth’s equator, making our Blue Marble bulge out, like a basketball with a guy sitting on it. This type of shape is called an oblate spheroid.
If you measure between the north and south poles, the Earth’s diameter is 12,713.6 km. If you measure across the Equator it’s 12,756.2 km, a difference of about 42.6 kilometers. Uh-oh! That’s more than our tolerance for a billiard ball. So the Earth is smooth enough, but not round enough, to qualify as a billiard ball.
The article also answers the question what would happen if you were to drill a hole all the way to the other side of the Earth and jump in. It lets you know about the Earth’s four other moons, why the Earth is growing bigger and more.
And then finally it notes that while it is a relatively easy job to destroy all life on Earth, destroying Earth itself is much harder that you might have been led to believe from watching Star Wars.