On the calendar
Solstices and equinoxes
The four turning points of the year.
When and where to look
Around 20 March, 21 June, 22 September and 21 December. The seasons are reversed in the southern hemisphere, so June brings its shortest day.
Why it happens
At the solstices the sun reaches its furthest point north or south, giving the longest and shortest days. At the equinoxes it crosses the equator, and day and night are close to equal everywhere.
The next dates
- December solstice, Monday 21 December (UTC)
- March equinox, Saturday 20 March (UTC)
- June solstice, Monday 21 June (UTC)
- September equinox, Thursday 23 September (UTC)
How to catch one
- Mark where the sun sets on the solstice; it is the furthest it will go all year.
- At the equinoxes the sun rises due east and sets due west.
- Watch the light change in the weeks around them; days change fastest near the equinoxes.
Nature notifications
Wildlife, seasonal changes, weather and sky events near you.