Rachel
About
Khan Academy on a Stick
How earth's tilt causes seasons
How being Earth's tilt causes seasons
Earth's rotation and tilt
Seasons aren't dictated by closeness to sun
How earth's tilt causes seasons
Are southern hemisphere seasons more severe?
Milankovitch cycles precession and obliquity
Precession causing perihelion to happen later
What causes precession and other orbital changes
Apsidal precession (perihelion precession) and Milankovitch cycles
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