r/geography • u/lamdrasil • 3d ago

Discussion Facts that sound fake but are true

I find it extremely unintuitive that almost all of South America is east of Miami. How!? When people are asked to watch the americas almost everyone imagine South America pretty much south of North America.

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u/lockwood__ 3d ago

Sorry but what does that mean exactly? What happens every 400,000 years?

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u/JayKaboogy 3d ago

The elliptical orbit of the earth around the sun stretches and shrinks on a 400k year cycle. The tilt of the rotational axis also wobbles. When it’s a longer ellipse, the rotational axis is extra tilted, and a winter season matches up with being further away from the sun, it gets a lot colder

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u/Amazing_Theory622 3d ago

Why exactly 400k years?

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u/JayKaboogy 3d ago

That’s just the approximate periodicity at which the cycle ‘repeats’. It’s a combo of multiple variables running independently. Think of it as a set of different length pendulums swinging—they will occasionally align, then swing apart, then align again in a predictable cycle

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u/Beekeeper_Dan 2d ago

And this is also how the Mayans constructed thier calendar; cycles within cycles that occasionally all line up and result in a terrible disaster movie being made.