Summer begins on Thursday, June 20, with the summer solstice, which begins at 8:51 PM (Lisbon time) and ends on September 22, with the arrival of autumn. With it also comes the longest day of the year, and therefore the shortest night, in the Northern Hemisphere.

According to one Publishing From the Lisbon Astronomical Observatory, the solstices correspond to “points on the ecliptic where the Sun reaches its heights.” [distância angular] Maximum and minimum relative to the equator, i.e. the points where the solar declination is maximum: maximum at the summer solstice [+23° 26′] The minimum is at the winter solstice [-23° 26′]”.

A word of Latin origin [solstitium] This is related to the Sun stopping its daily movement away from the equatorial plane and “stopping” when it reaches its highest or lowest position in the local sky,” the note adds.

The phenomenon is being celebrated around the world, particularly at the famous prehistoric site of Stonehenge, in England, the block of which was spray-painted on Wednesday by activists from the environmental organization Just Stop Oil.

in Publishing On Facebook, geologist Antonio Galobim de Carvalho highlights that this is “a special moment in the position of the Sun, in its apparent movement.” “Solstice or the sun that does not move” [do latim ‘solis’ e ‘sistere’] It is the moment when the star, during its apparent movement, reaches the greatest deviation in latitude as measured from the equator. It is known that the Latin term “sister“It refers to the fact that the Sun, when viewed from Earth, appears stationary, maintaining a fixed position as it rises and sets, which it does for some time,” the publication adds.

Gallopim de Carvalho also remembers that there are always two solstices a year – in the Northern Hemisphere, there is the summer solstice (this Thursday at 8:51 p.m.) and the winter solstice (in December).

The geologist also asserts that the summer solstice “marks the beginning of the hottest season of the year” and “has the longest day and shortest night.” “In winter, on the contrary, we will have shorter days and nights with more hours and minutes.”

In the Southern Hemisphere, says Gallobim de Carvalho, “the phenomenon is symmetrical, or in other words, everything happens in the opposite direction.”