June solstice

The June solstice is the solstice on the Earth that occurs each year falling on 20–22 June according to the Gregorian calendar. In the Northern Hemisphere, the June solstice is the summer solstice (the duration of daylight is longest than of night), whilst in the Southern Hemisphere it is the winter solstice (the duration of night is longest than of daylight). It is also known as the northern solstice.
Solar year.
The June solstice solar year is the solar year based on the June solstice. It is thus the length of time between adjacent June solstices.
In 6000 BC, the December solstice solar year had a length of 50:35 in excess of 365 days and 5 hours. This shortened to 47:55 in 2000 AD. It will remain between 47:45 and 48:00 at least until 10000 AD.