When the sun’s rays are direct, the area receives more energy and the season is summer. When the sun’s rays are indirect, the area receives less energy and the season is winter. During Spring and Fall, the sun’s rays hit the northern and southern hemispheres evenly. Both hemispheres receive the same amount of direct sunlight and the temperatures are mild. This image shows the seasons in the northern hemisphere.
Astronomical seasons are based on the tilt of the earth in its orbit around the sun and its tilt. The solstices are the maximum and minimum sun strength at the poles. The sunlight for both hemispheres is equal during the equinoxes. Meteorological seasons are based on temperature, plant life, precipitation, and the months of the year. Spring and fall are usually mild, summer is warmest, and winter is coldest.
The astronomical seasons stay mostly constant, and the meteorological seasons change.