earth turning over

been thinking about Earth lately.
What would happen if the earth wasn’t tilted 23 degrees?

Also, what would happen if the earth slowly turned on its side?
Weather, vegetation, etc.

thanks in advance.

If the earth were exactly perpendicular to its plane of orbit, there would be no seasons. The average temperature would be the same all over the place.

If the earth began to turn on its side, so its axis of rotation was pointing right at the sun, then one hemisphere (north or south) would get really hot, and the other would get really cold.

also, the ice at the poles would melt yes?

Well, yes, technically speaking the results could be expected to be relatively dramatic. I don’t know that I’d use “catastrophe” to describe the expected changes, however. I’d be more inclined to refer to them as, well, unflippingbelievable. Catastrophic? No. Just very, very different from the way things are now, that’s all. If the change happened suddenly, like, between Lunch and 4:pm assuming we all weren’t thrown off the planet by our momentum, I think it’d be survivable to some extent. Humans are pretty good at migrating, I’m sure enough could get to the hospitable places to ensure the survival of our own species. Cats, too, would probably survive as well as lap-dogs and possibly some reodents. The other critters would probably have to look after themselves.

vanilla, I am betting that with the slow rate of change the poles would just creep as one side got hotter and the other colder.

Not quite. Conservation of angular momentum keeps the north and south poles directed at the same location in space. If the earth’s the axis of rotation was directed towards the sun, each hemisphere would have a hot day 1/2 a year long, followed by a wintry night 1/2 a year long.

That’s right;
the average temperature would stay the same, more or less, but the summer would be marked by months of permanent sunshine and heat, while the winter would be months of darkness and cold.
The hot air and water on one side would flow towards the cold side and vice versa; causing bizarre weather putting hurricane Isabel to shame.

SF worldbuilding at

Good point, Squink, I had forgotten about the angular momentum.


No, there would still be variations in average temperature from the equator to the poles, for the same reason there is now: The sun hits the ground at a more oblique angle at higher latitudes, meaning the same amount of incident light has to warm more ground near the poles.

If the population of china ran round the earth 10[sup]12[/sup] (a trillion) times we could find out! (If my calculations are correct.)

With conservation of angular momentum, the really interesting place to live would be on the equator. You’d have equal days and nights at the equinoxes, but at the solstices the sun would be doing a 360 around the horizon.

Correct. Each point on Earth would have a more-or-less steady temperature with none of the wild summer-to-winter swings, though what that temperature is depends largely on distance from the equator.

But for the sake of completeness, I’ll just mention that Earth’s orbit is not a perfect circle, and the temperature difference between apogee and perigee may become noticeable if the seasons disappear, with “winter” (for the entire planet) being apogee. “Hey remember the winter of '34? Why the ambient dropped a whole three degrees! BRRRR! Kids today have no backbone.”