this post was submitted on 26 Jul 2025
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No, I still mean it. The variance from pole to equator is 0.5%.
Although it's technically an oblate spheroid, technically anything you think of as a "sphere" isn't a sphere either.
This is why it makes sense to talk about the earth scaled to objects you can comprehend. Is a ping pong ball a sphere? Is a basketball a sphere? When you blow bubbles, are those spheres?
Be consistent with your pedantry. Either they are and so is the Earth, or none of them are.
True enough! Still, I can't imagine a billiard ball with tolerances like that. I've shot 1,000 games and a ball being .5% off would be noticeable.
Enough anecdotes! Let's get to evidence. Leaving in a few to hit the river, but this looks really interesting for when I get back:
https://possiblywrong.wordpress.com/2011/01/03/is-the-earth-like-a-billiard-ball-or-not/
Other sources agree, the ball's .005% spherical tolerance is an order of magnitude tighter than Earth's. However, haven't read the whole thing, gotta go.