What is the Summer Solstice?

What is the Summer Solstice?

The earth, like all planets, is in constant motion. It orbits the sun, making a complete revolution in about 365.25 days, the calculation we use to make our year. (The fraction of a day is also the origin of our leap year). While orbiting the sun it also rotates, a cycle that takes about 24 hours to complete. This rotation, causing differing parts of the earth to be exposed either to darkness or light creates our days and nights.

This does not answer our question, though: what is the summer solstice? The answer lies in the fact that these cycles of rotation and revolution are not done in perfect circular motions. As the earth orbits the sun it tilts. In the summer months the northern half of the earth is tilting towards the sun, in winter the southern half is tilting towards the sun. (Unless of course you live in the southern hemisphere and then it is the opposite).

Summer solstice is that time of year when the north pole is tilted at its most extreme towards the sun. For us here on earth, the sun takes a higher and longer path through the sky, giving us longer days. On the day of the summer solstice, the day when we are at this most extreme tilt, it is the longest day of the year.

June 21st is the date on which summer solstice generally falls in the Gregorian calendar. In North America, the summer solstice is also seen to be the first day of summer. This differs from our counterparts in the United Kingdom and elsewhere throughout the northern part of the world who see the solstice not as the beginning of summer but as midsummer.

Our word solstice comes from Latin. The word sol means sun, while sistere means to cause or stand still. To the ancient Romans the sun seemed to stand still on the date of the solstice. While prior to the date of the summer solstice the sun would rise noticeably higher each noonday, on the date of the summer solstice it would move almost not at all from the day before, nor would it move greatly the next day as it began its descent.

Celebrations of the Summer Solstice