Meaning of Equinox
What is Equinox:
The equinox is the time of year when day and night have the same duration because the Sun is on the equator of planet Earth. The word, as such, comes from Latin aequinoctĭum, which would come to translate 'equal night'.
The equinox takes place twice a year, between March 20 and 21 and September 22 and 23. As such, it is the astronomical event that marks the beginning of spring and fall, depending on which hemisphere we are in.
In other words, if we are in the northern hemisphere, the March equinox will mark the beginning of spring, and the September equinox will mark the beginning of autumn. While if we are in the south, the March equinox will mark the beginning of autumn and that of September, that of spring.
During the equinox, the Sun reaches its zenith, that is, the highest point in the sky, at 90 ° relative to a person on Earth. This means that the parallel of declination of the Sun and the celestial equator coincide on that day.
In the days of the equinox, on the other hand, the two Earth's poles are at the same distance from the Sun, which means that the light projected on the Earth is the same for both hemispheres.
The vernal equinox is related to rebirth. It marks the start of the growing season and greening of nature. Hence the festival of Easter, eggs and rabbits, symbols of fertility par excellence.
The autumnal equinox, for its part, marks the retreat of the Sun, the fall of the leaves, the beginning of the coldest season of the year, the end of the harvests, and the migration of birds.
Equinox and solstice
The solstice is called, in astronomy, the astronomical event in which the Sun reaches its highest or lowest height in the sky and, as a consequence of this, the duration of the day or night is the maximum of the year. The solstice, as such, marks the beginning of winter and summer, and takes place between June 21 and 22, and December 21 and 22.
The equinox, for its part, differs from the solstice in that it is the time when night and day have the same duration, this is because the sun reaches its zenith, that is, the highest point in the sky, at 90 ° from the position of a person located on Earth. On the other hand, the equinox marks the beginning of spring and autumn, between March 20 and 21, and September 22 and 23.