Solstice << SOL stihs >> is one of the two moments each year when the sun is at either its northernmost or southernmost position. The sun appears directly overhead at different latitudes during the year. The change results from the tilt of Earth’s axis of rotation. The axis is tilted at an angle of 23 degrees 27 minutes in relation to the plane of Earth’s orbit around the sun.
One solstice occurs on June 20, 21, or 22. At this moment, the sun reaches its most northerly point. It is directly overhead at the Tropic of Cancer (23 degrees 27 minutes north latitude). The other solstice happens on December 21 or 22. The sun appears at its most southerly position. It is directly overhead at the Tropic of Capricorn (23 degrees 27 minutes south latitude).
In the Northern Hemisphere, the June solstice is known as the summer solstice. Likewise, the December solstice is called the winter solstice. The day of the summer solstice in the Northern Hemisphere marks the beginning of summer. The summer solstice occurs on or near the longest day of the year. Similarly, the winter solstice occurs on or near the shortest day of the year. It marks the beginning of winter. In the Southern Hemisphere, summer and winter are reversed.
See also Equinox; Season; Tropic of Cancer; Tropic of Capricorn.
