this post was submitted on 26 Jul 2025
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The earth isnt a perfect sphere though; that measurement is different for the same amount of angular rotation, depending on where you measure from. Just use degrees...
The earth is a more perfect sphere than a billiards ball is.
We forgot how big the earth is. Despite the obvious variance we see from our perspective... We are microscopic.
Again, I understand your point, but I better not ever catch you describing distance in terms of time. That would be peak hypocrisy.
No, Earth is an oblate spheroid. What you're thinking of is the fact that Earth is smoother than a billiard ball. Freaky, but true!
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.