this post was submitted on 26 Jul 2025
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tilted 31.5 inches...? Tf are you talking about. How do you rotate something by a linear distance...
The linear travel of a point on its surface as a result of the rotation.
It's like saying you have a friend who lives 15 minutes away.
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.
It's in the article.
Did you...read the article?
The point on the planet that is true north, where an imaginary arrow pokes out of the top of an Arctic glacier and we all spin around it, the north pole where Santa lives, moved due to groundwater use shifting the mass distribution of the planet. Our wobble is extra wobbly and shouldn't be.
Not surprising, science is done in proper metric to start with.
But this is an American outlet reporting on science..
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That was two clicks away - so you're right: the property science wasn't some in fridges or football fields or any of the US scales.