Farther south, at earth's equator, the north celestial pole lies on the northern horizon, and the celestial equator passes straight overhead. From here, as the constellations rise in the east, they appear to head straight up, rather than along a diagonal. In the west, they head straight down as they set. Equatorial regions experience only small seasonal changes in temperature due to the relatively constant angle between these regions and the sun. The figure on the right shows how seasons are determined by the tilt of the earth's rotational axis and the orbit of the earth around the sun.

Equatorial regions experience only small seasonal changes in temperature due to the relatively constant angle between these regions and the sun. The figure on the right shows how seasons are determined by the tilt of the earth's rotational axis and the orbit of the earth around the sun. There are only small seasonal changes in temperature at lower latitudes with increasingly larger seasonal changes in temperature at higher latitudes. Sunlight hits the Earth most directly at the Equator. The curve of the Earth means that sunlight is spread over a wider area the further you move from the Equator. Sunlight hits a smaller surface area at the Equator so heats up quickly compared to the poles. The polar vortex forms every winter because of the temperature difference between the equator and the poles. In the polar stratosphere, sunlight basically gets cut off during the late fall and early winter – and that makes it really cold, while the equator remains quite warm. The difference of temperature between pole and equator is evaluated by Woolley's method of the calcium ionization temperature. The pole is found to be hotter than the equator by 96° ± 18° or 86° ± 16°, depending upon the choice of the values of the continuous absorption coefficients. At the equator, there are no circumpolar stars because the celestial poles are located at the horizon. All stars observed at the equator rise in the east and set in the west. Due to Earth's axial precession the constellations through which the celestial equator passes will also change over time.

Seasonal changes in temperature at the equator and throughout the tropics are minor. As you move further away from the Equator, seasonal changes become more severe, and the largest seasonal changes occur at the north and south poles and throughout the Arctic and Antarctic regions. Sunlight hits the Earth most directly at the Equator. The curve of the Earth means that sunlight is spread over a wider area the further you move from the Equator. Sunlight hits a smaller surface area at the Equator so heats up quickly compared to the poles. Equatorial regions experience only small seasonal changes in temperature due to the relatively constant angle between these regions and the sun. Because the sun's rays hit the earth's surface at a higher angle at the equator. Earth's tilted axis causes the seasons. Throughout the year, different parts of Earth receive the Sun's most direct rays. So, when the North Pole tilts toward the Sun, it's summer in the Northern Hemisphere and when the South Pole tilts toward the Sun, its winter in the Northern Hemisphere. However unlike other latitudes, the equator receives vertical rays of sunshine throughout the year. These regions experience less seasonal variations. The equatorial regions experience equal day and night throughout the year. Equatorial region has a warm climate throughout the year. Hence, seasonality will mostly depend on the latitude. For high latitudes where annual heat variations are large, the seasonal divisions are spring, summer, autumn and winter, while in lower latitudes where heat variations are less relevant, rainfall changes define dry and wet seasons