There are many ways to quantify the summer season. Memorial Day weekend signals the start of summer for beachgoers and vacationers across the United States. Weather forecasters declare June 1 as the beginning of meteorological summer, while others wait until the June solstice to welcome the arrival of astronomical summer.
Solar summer, one of the lesser-known versions of the season, has been with us for a full month. May, June and July are the months when the Northern Hemisphere receives the most sunlight due to the Earth’s tilt on its axis. Because of this, the three-month period is known as solar summer.
Despite the Northern Hemisphere receiving more sunlight from May through July than any other months of the year, it is usually not the hottest three-month span. This is due to a lag between when the Northern Hemisphere receives the most amount of sunlight and when the atmosphere is at its warmest point of the year.
The “dog days of summer” is yet another way to quantify the season and is the shortest of the bunch, starting on July 3 and ending on August 11. During this 39-day period, Sirius—known as the dog star—is in the same area of the sky as the sun.
In ancient times, it was thought that the added light from Sirius (the brightest star in the night sky) added extra heat to the day. However, the star is nearly 6 trillion miles away from Earth, and its light is too dim to change the temperature on our planet.
