Were it not for the ancient Greeks there would be no dog days of summer. The expression may spark visions of canines barking in the heat, but the moniker has nothing to do with ‘dogs’.

Ancient civilizations tracked the seasons by looking to the sky. The ancient Greeks noticed that summer was most hot during the approximate 40-day period in the early summer when Sirius, the brightest star in the sky, rose and set with the sun. Sirius, in ancient Greek, represented glowing with the sun bringing extreme heat. Sirius was the dog of hunter Orion. Ancient Romans placed the star in the constellation Canis Major. Romans refered to the period when the summer heat was the hottest as the “dies caniculares” or “days of the dog star”.

The shifting position of the Earth’s rotation has changed the dates of the “dog days” that are several weeks later to what they were in antiquity.