Thursday was the longest day of the year in the part of the world that lies north of the equator including India as it witnessed the Summer Solstice.
Summer solstice is an astronomical phenomenon which occurs on June 21, when the sun reaches its northern-most point from the celestial equator. This phenomenon occurs when earth’s axial tilt is most inclined towards the Sun.
According to Dr P Iyamperumal, executive director, Periyar Science and Technology Centre, B M Birla Planetarium, Chennai, “Thurday was the longest day due to the solstice. And in Chennai we had the Sun for 12-and-a-half hours, with the Sun rising at 5.30 am and shining till 6.15 pm followed by twilight.”
During summer solstice, the northern hemisphere witnesses its longest day of the year while the southern hemisphere sees its shortest. After summer solstice, the length of the day starts decreasing and it reaches a point when day and night become equal in length.
Summer solstice celebrations are observed in some countries closer to the pole as for them this day marks the beginning of the summer. The summer solstice in the southern hemisphere is on December 22.