Why do the seasons in the Northern and Southern Hemispheres come on different dates?

The seasons do not match due to the tilt of the earth’s axis. While moving in orbit, the Earth turns to the Sun at one or the other pole.
The axis of the Earth during rotation around the Sun maintains a constant inclination to the plane of the orbit. The northern and southern hemispheres are heated unevenly. When the southern hemisphere is facing the sun and there is summer, the northern hemisphere is in the shade and there is winter.

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