The Earth's axis is tilted about 23.5° with respect to its orbital plane around the Sun.
©bigstockphoto.com/vjanez
To prove his theory, Foucault suspended a lead-filled brass sphere, now called the Foucault Pendulum from the top of the Pantheon in Paris.
He showed that the plane of the swing of the pendulum rotated relative to the Earth’s rotation. You can now see the Foucault Pendulum demonstrating the rotation of the Earth in science museums around the world.
How to Celebrate?
- Visit your local space and science museum to learn more about the Earth’s rotation and what effect it has on humans.
- If you have kids, what about making a model of the Earth and the Sun with them, so that they can learn more about the Earth’s rotation?
Did You Know…
...that the speed of the Earth's rotation can change from day to day and from year to year?
Earth's Rotation Day Observances
| Year | Weekday | Date | Name |
|---|---|---|---|
| 2025 | Wed | Jan 8 | Earth's Rotation Day |
| 2026 | Thu | Jan 8 | Earth's Rotation Day |
| 2027 | Fri | Jan 8 | Earth's Rotation Day |
| 2028 | Sat | Jan 8 | Earth's Rotation Day |
| 2029 | Mon | Jan 8 | Earth's Rotation Day |
| 2030 | Tue | Jan 8 | Earth's Rotation Day |
| 2031 | Wed | Jan 8 | Earth's Rotation Day |
| 2032 | Thu | Jan 8 | Earth's Rotation Day |
| 2033 | Sat | Jan 8 | Earth's Rotation Day |
| 2034 | Sun | Jan 8 | Earth's Rotation Day |