Earth and the Moon

The Seasons

What is the difference between the ecliptic plane and Earth’s equatorial plane?

The equatorial plane is the plane of Earth’s equator extended indefinitely out into space. It turns out that Earth’s rotation around its axis is not lined up with the ecliptic plane. Instead, Earth is tilted about 23.5 degrees. This tilt is the main cause of the

Because Earth is slightly tilted on its axis, sunlight strikes our planet at different angles depending on the time of year. Thus, the northern and southern hemispheres warm and cool at different times, causing the seasons we experience.


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