The seasons are the result of our close luminary, the sun, traveling north and south 5200 klms between the tropics of Cancer and Capricorn from June through December respectively, Just as we observe.
We can use a Day and Night map to show where the sun is at any given time. The yearly cycle between the tropics is a wave, similar to the day and night section of this map. We can also use waves to show seasons, as the sun daily moves east to west so the yearly wave also moves east to west.
Wave showing the suns yearly journey between the tropics:
Summer in the North (June):
Summer in the South (December):
Seasons:
