India, June 21 -- It brings the longest day and shortest night of the year for the 88 per cent of Earth's people who live in the NorthernHemisphere

The summer solstice marks the official start of summer. It brings the longest day and shortest night of the year for the 88 percent of Earth's people who live in the Northern Hemisphere. People around the world observe the change of seasons with bonfires and festivals and Fete de la Musique celebrations .

The solstice is the 24-hour period during the year when the most daylight hits the Northern Hemisphere. Przemyslaw 'Blueshade' Idzkiewicz, CC BY-SA

Astronomers can calculate an exact moment for the solstice, when Earth reaches the point in its orbit where the North Pole is angled closest t...