Seasons happen because Earth’s axis is tilted at an angle of about 23.4 degrees and different parts of Earth receive more solar energy than others. Four seasons — autumn, winter, spring and summer occur throughout the year. The timing of the seasons is opposite for each hemisphere. This is because when the North Pole is tilted toward the sun, the Northern Hemisphere faces the sun at a greater angle than the Southern Hemisphere.
During the winter solstice, the sun is at its lowest path in the sky, resulting in the shortest day of the year. Summer is the season with the longest days and warmest temperatures, with winter being the opposite. Spring represents the time when the days start to get longer, with more hours of sunlight.