Earth's orbit

[1dave]

AI Overview

Over long periods of time, Earth's orbit around the sun changes shape, shifting from nearly circular to slightly elliptical due to the gravitational influence of other planets like Jupiter and Saturn, causing variations in the amount of sunlight reaching Earth and impacting climate cycles, known as Milankovitch cycles; these changes occur over tens of thousands to hundreds of thousands of years, with the primary factors being the eccentricity (how elliptical the orbit is), axial tilt (obliquity), and precession (wobble of the Earth's axis).
Key points about Earth's changing orbit:

Eccentricity:

This refers to how much the Earth's orbit deviates from a perfect circle. When eccentricity is high, the Earth experiences more extreme seasonal variations as it is significantly closer to the sun at one point in its orbit than at another.

Axial Tilt (Obliquity):

The angle at which Earth's axis is tilted relative to its orbital plane. This tilt is responsible for the seasons. While the tilt itself is relatively constant, it can slowly vary over long time periods.
Precession:
A slow wobble in Earth's rotational axis, causing the "North Star" to change over thousands of years.

How these changes affect Earth's climate:

Ice Ages:

When Earth's orbit becomes more elliptical, and the Northern Hemisphere experiences more extreme seasons, it can contribute to the onset of ice ages.

Seasonal Variations:
Changes in axial tilt can lead to more or less extreme seasonal variations in different parts of the world.

Time scales of orbital changes:

Eccentricity: Cycles typically occur over 100,000 to 400,000 years.

Axial Tilt: Changes in tilt happen over a cycle of around 41,000 years.
Precession: A complete precession cycle takes around 26,000 years.

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Generative AI is experimental.
Over time, the pull of gravity from our solar system's two largest gas giant planets, Jupiter and Saturn, causes the shape of Earth's orbit to vary from nearly circular to slightly elliptical.Feb 27, 2020

Length of Days has changed with each new Period of Geological Time

In my opinion, those changes, including tilt, and speed were caused by huge impacts of Asteroids or Comets. The first one was the planet that hit earth and created our moon.

phys.org/news/2023-06-billion-years-earth-history-days.html