Today we’ll have summer solstice, one extreme point in Earth’s seasonality. The result of Earth having a tilted axis. On June 21 (or around) is the time when the Sun is at its highest or most northerly point in the sky and when we receive the most hours of daylight.
Above image: Diagram of the Earth‘s seasons as seen from the north. Far left: summer solstice for the Northern Hemisphere. Front right: summer solstice for the Southern Hemisphere. Credit wikimedia
The summer solstice occurs when the tilt of a planet’s semi-axis, in either the northern or the southern hemisphere, is most inclined toward the star (sun) that it orbits. Earth’s maximum axial tilt toward the sun is 23° 26′. This happens twice each year, at which times the sun reaches its highest position in the sky as seen from the north or the south pole.
The summer solstice occurs during a hemisphere’s summer. This is northern solstice in the northern hemisphere and the southern solstice in the southern hemisphere. Depending on the shift of the calendar, the summer solstice occurs some time between December 20 and December 23 each year in the southern hemisphere and between June 20 and June 22 in the northern hemisphere.