The astronomical start of a season is based on the position of the Earth in relation to the Sun. The start of each season is marked by either a solstice (winter and summer) or an equinox (spring and autumn). A solstice takes place when the Sun reaches the most southerly or northerly point in the sky, while an equinox marks the point when the Sun passes over Earth’s equator.

The summer solstice occurs when one of the Earth’s poles, the north pole in the case of the Northern Hemisphere, has its maximum tilt towards from the Sun. It happens twice yearly, once in each hemisphere. The summer solstice is the day with the longest period of daylight and shortest night of the year. The Sun is today at its highest daily maximum elevation in the sky. At the pole, there is continuous light around the summer solstice. The summer solstice marks the beginning of summer. Because of leap years, the dates of the equinoxes and solstices can shift by a day or two over time, causing the start dates of the seasons to shift too. For instance, this year, summer starts on Saturday, June 20th and not on Sunday, June 21st!

Since prehistory, the summer solstice has been seen as a significant time of year in many cultures, and has been marked by festivals and rituals. On the first day of each season, the rises in a particular alignment to the prehistoric temples of Ħaġar Qim and Mnajdra. They are so systematic that it is very probably that these orientations were intentional. In prehistory, the observation of the motion of celestial bodies was related to the changing season and times of planting and harvesting of crops.

From tomorrow onward, the length of the day will start decreasing again! For those of you who love winter, see this day as the start of the road to winter.