When is the summer solstice 2022 and why do the dates vary? Here is everything you need to know about the longest day of the year

The summer solstice, also known as midsummer or estival solstice, symbolises the first official day of summer.

It occurs twice in a year, once in each hemisphere: Northern and Southern and for that hemisphere, the summer solstice is when the sun reaches its highest point in the sky in areas outside of the tropics and is the day with the longest period of daylight and shortest night of the year.

Here is everything you need to know about the summer solstice.

When is the summer solstice 2022?

This year, the summer solstice will occur on Tuesday, June 21 at 9.14am.

It changes by a few days every year; in 2020 it occurred on Saturday, June 20 at 9.43am.

Why do the summer solstice dates change every year?

Whilst the summer solstice is the longest day of the year for that hemisphere, the dates of the earliest sunrise and latest sunset do vary by a few days.

This is due to the Earth’s orbit around the sun in an ellipse, and its orbital speed varies slightly during the year.

Within the Arctic circle (for the northern hemisphere) or Antarctic circle (for the southern hemisphere), there is continuous daylight around the summer solstice.

The summer solstice occurs - of course - during the summer and this is the June solstice in the northern hemisphere and the December solstice is in the southern hemisphere.

Depending on the shift of the calendar, the summer solstice takes place sometime between June 20 and June 22 in the northern hemisphere.