The June solstice is the summer solstice in the Northern Hemisphere and the winter solstice in the Southern Hemisphere. The winter solstice is the shortest day of the year and has the fewest hours of daylight. The summer solstice is the longest day of the year, meaning it experiences the maximum intensity of the sun’s rays and has the most hours of sunlight. During an equinox, solar declination is 0°-the Equator-and both the Northern and Southern Hemisphere receive equal sunlight.) Sometimes, solstices are nicknamed the “ summer solstice” and the “ winter solstice,” although these have different dates in the Northern and Southern Hemispheres. (The only times of the year when the intensity of the sun’s rays is not unequal are the appropriately named equinoxes. Throughout the year, this means that either the Northern or Southern Hemisphere is tilted toward the sun and receives the maximum intensity of the sun’s rays. Solstices and shifting solar declinations are a result of Earth’s 23.5° axial tilt as it orbits the sun. During the December solstice (marked between December 20 and December 23), solar declination is about 23.5°S (the Tropic of Capricorn). During the June solstice (marked between June 20 and June 22), solar declination is about 23.5°N (the Tropic of Cancer). On Earth, solstices are twice-yearly phenomena in which solar declination reaches the Tropic of Cancer in the north and the Tropic of Capricorn in the south.

On our planet, solstices are defined by solar declination-the latitude of the Earth where the sun is directly overhead at noon.

A solstice is an event in which a planet’s poles are most extremely inclined toward or away from the star it orbits.

Winter equinox