The solstice

The solstices (from the Latin solstitium (sol sistere, “Sun quiet”) are the times of the year in which the Sun reaches its greater or less apparent height in the sky, and the duration of the day or of the night are the maximums of the year, respectively. Astronomically, solstices are the times when the sun reaches the maximum north (+ 23 ° 27 ‘) or south (-23 ° 27’) with respect to the terrestrial equator. On the summer solstice of the northern hemisphere, the sun reaches the zenith at noon on the tropic of Cancer and at the winter solstice reaches the zenith at noon on the tropic of Capricorn. It occurs twice a year: on June 20 or 21 and on December 21 or 22 of each year. Throughout the year the position of the Sun seen from the Earth moves towards the North and to the South. The existence of the solstices is caused by the inclination of the axis of the Earth on the plane of its orbit.

On solstice days, the duration of the day and the altitude of the Sun at noon are maximum (at the summer solstice) and minimum (at the winter solstice) compared to any other day of the year. In most of the ancient cultures festivals were celebrated commemorating the solstices. In temperate zones, the dates of the solstices are identical to those of the astronomical passage from spring to summer and from autumn to winter. The dates of the winter solstice and the summer solstice are inverted in both hemispheres. Solstice is an astronomical term related to the position of the Sun on the celestial equator.

Afelio and Perihelio

Afelio is called the farthest point of a planet’s orbit relative to the sun. And it should not be confused with solstice. In contrast, perihelion is the antonym of aphelion, therefore it refers to the closest point of a planet’s orbit relative to the sun. Nor should it be confused with equinox.

The solstice is an astronomical event which is attributed to the beginning of Summer or Winter. These celestial events mark the times of the year in which the incidence of the solar rays are at the maximum or the minimum in the terrestrial surface, determining the longest and shortest day of the year respectively.

In the Northern Hemisphere, the Summer Solstice takes place between 21-23 June and the Winter Solstice takes place between December 21-23. By the geometry of the Earth and its movement around the sun, the Summer Solstice in the Southern Hemisphere happens at the same time as the Winter Solstice in the Northern Hemisphere and vice versa. Therefore, in the southern hemisphere, the summer solstice happens between December 21 to 23 and the winter solstice happens between June 21 to 23.The solstice is usually associated with the equinox which in Latin is commonly translated as “night and day equals”. As its name indicates, it points to the moment of the year in which day and night have the same duration and happens just between the solstices, ie, March 21 and September 21.

These dates have always been celebrated by humans, regardless of their region and / or culture. Current theories suggest that these rites associated with station moving may be inheritances of our Neolithic past, when man became dependent on agriculture and climatic conditions to survive. Because of the universal nature of the celebration and the devotion that the majority had to these festivals, some used these dates for their own motivation, such as the date of the birth of Jesus Christ put by the Catholic Church some days before the Winter solstice of the northern hemisphere. Find out more with related terms like the summer solstice, the equinox and the seasons of the year.