As we know, every year, June 21 is marked as the longest day of the year and the start of summer in the Northern Hemisphere.
Also known as the June Solstice, Summer Solstice usually falls on June 20 or June 21, and is the longest day of the year for the Northern Hemisphere, and the shortest for the Southern Hemisphere.
What happens on this day?
On that day, nearly 90 percent of the world’s population, who live above the equator in the Northern Hemisphere, will have the longest period of daylight in the year and also the shortest night.
Why this day is the longest one?
The summer solstice occurs when the sun is at its highest position in the sky. This happens once every year because the Earth’s axis is tilted by about 23.5 degrees relative to its orbital plane around the Sun. This tilt is also what causes the changing seasons.
For several days or weeks before and after June 21, those living in the Arctic, including parts of Alaska, Canada, Greenland, and Scandinavia, will have continuous daylight resulting in what is known as the midnight sun.
Is the longest day of the year also the hottest?
Despite being the longest day of the year, the day of the Summer Solstice is not the hottest day in the Northern Hemisphere. Rather, the hottest days of the year are experienced in late July and August.