What is the date of the summer solstice?
The summer solstice, it is the longest day of the year, date of the calendar where the night is the shortest. In the northern hemisphere, the summer solstice falls generally on June 21st (and sometimes on June 20th). But it is not always the case. Indeed, our civil calendar (the Gregorian calendar) account 365 or 366 days and is not perfectly synchronized with the cycle of rotation of the Earth around the sun (365,2422 days to be precise!). From where of small gaps, certain years … ? In June 21st: it is, in the great majority of the cases, the official date of the summer solstice. ? In June 20th: it had not arrived since[...]