WORLDWIDE — The “dog days” of summer are certainly here, and while you might picture canines baking in the oppressive heat, the saying's origin is anything but.
The phrase actually dates back to ancient civilizations who used to track seasons by what was happening in the sky.
According to History.com, ancient Greeks noticed that summer’s hottest heat occurred during the approximate 40-day period in the early summer when Sirius, the brightest star in the sky, rose and set with the sun.
Canis Major as depicted in Urania’s Mirror, a set of constellation cards published in London c.1825. Credit: Library of Congress.
The daytime addition of the warmth of Sirius — ancient Greek for “glowing” or “scorcher”— to the blaze of the sun equaled extreme heat.
In Greek mythology, Sirius was the dog of the hunter Orion, and the ancient Romans placed the star in the constellation Canis Major, Latin for “Greater Dog.”
Thus the stifling period when the rising of the sun and Sirius converged as the “dies caniculares” or “days of the dog star.” By the 1500s, the English world began to call the same summertime point on the astronomical calendar as the “dog days.”
Though dates vary depending on where you are in the world, Old Farmer’s Almanac reports the traditional timing of the “dog days” in the United States is between July 3 and Aug. 11.