Imagine if Earth's axis tilted to zero degrees, or parallel to its orbital plane. Things might get pretty wild and hairy. If my calculations are correct, every year both polar regions would cycle between oven-hot and a freezer-cold, while the central regions would cycle from tropical summers to very cold, dark winters. Just thinking about it makes me shiver.

@bunnyknightsaid Imagine if Earth's axis tilted to zero degrees, or parallel to its orbital plane. Things might get pretty wild and hairy. If my calculations are correct, every year both polar regions would cycle between oven-hot and a freezer-cold, while the central regions would cycle from tropical summers to very cold, dark winters. Just thinking about it makes me shiver.

Please define the "zero".
You mean the axid perpenticular to the elliptic plane, then there wouldn't be any seasons.
You mean the axis pointing to the sun (the erath "rolling" on the perpenticualr plane, there wouldn't be any season, the pole pointing to the sun would be scorching, the pole pointing away would be freezing.

The case of (the axis in direction of the plane with the axid tangentailly to the elliptic palne would is not stable, please show us your calculation in the angular moment)

@ponderablesaid Please define the "zero".
You mean the axid perpenticular to the elliptic plane, then there wouldn't be any seasons.
You mean the axis pointing to the sun (the erath "rolling" on the perpenticualr plane, there wouldn't be any season, the pole pointing to the sun would be scorching, the pole pointing away would be freezing.

The case of (the axis in direction of the pl ...[text shortened]... ly to the elliptic palne would is not stable, please show us your calculation in the angular moment)

That's why I added "parallel to its orbital plane" just in case zero degrees is too hard to understand. And each pole would only point at the sun once a year, due to the gyroscopic effect of Earth's daily rotation.

@bunnyknightsaid That's why I added "parallel to its orbital plane" just in case zero degrees is too hard to understand. And each pole would only point at the sun once a year, due to the gyroscopic effect of Earth's daily rotation.

I've forgotten which one, but I think one of the other planets in our solar system does just that... the axis is parallel to it's orbital plane.

@lemon-limesaid I've forgotten which one, but I think one of the other planets in our solar system does just that... the axis is parallel to it's orbital plane.

That is Uranus, it's axisis inclined by 97.7° (It is bigger than 90° to account for the fact that is turning the other direction than the other planets).

@ponderablesaid That is Uranus, it's axisis inclined by 97.7° (It is bigger than 90° to account for the fact that is turning the other direction than the other planets).

@venda With the axis pointing at the sun it doesn't matter which way it revolves, the one aiming at the sun at max will get the max energy and the other side the opposite but that swaps around every 180 degrees of its journey around the sun. So about every 42 years each pole gets max energy so there is a slow swing around the sun and also 21 years from that the equator gets a shot at that energy.