People gather around Stonehenge for the rising of the sun on the 2015 summer solstice.
The term solstice comes from the Latin words "sol," meaning sun, and "sistere," meaning to come to a stop or stand still. During the summer solstice, the sun reaches its highest position in the sky. Instead of continuing in a forward motion as it does every other day, the sun appears to stand still before reversing directions and moving to the south again.
Because the solstice occurs at the moment the sun is directly over the Tropic of Cancer, it happens at the same time for everyone in the world. However, since we have time zones, this could be today or tomorrow, depending on where you are located. Time and Date has a calculator for everyone to find out the exact moment of the summer solstice in their particular location.
This day comes and goes each year, but before it goes away again, here are 5 cool summer solstice facts to consider on the longest day of the year.