We are in the throes of the “dog days” of summer. Most modern almanacs refer to this period by the Roman name dies caniculus which they note as July 3 through Aug. 11. The first English written record of dog days comes from Sir Thomas Elyot’s dictionary of 1538. The reference to dog days, however, is ancient.

The story is wrapped in the mythology of the star, Sirius. The name is thought to have evolved from the Greek word seirios. Translations for seirios include “searing, sparkling and scorcher.”

Egyptian hieroglyphs dating from 3285 B.C. record the star as a dog. The Phoenicians called the star Hannabeah, “the barker.”

Sirius is the brightest star in the heavens, over 20 times brighter than the sun and twice as massive. It is the prominent star of the constellation Canis Major.

Most of the winter, the two dogs - Canis Major and Canis Minor - follow the hunter, Orion, through the night skies. During this time Sirius is easily found brightening the nights. To find the dog star, draw an imaginary line through the three stars of Orion’s belt and extend it southeastward. The line will pass just north of the bright bluish-white glow of Sirius. As the earth spins its way into spring and summer the glow of Sirius fades from the night sky.

Ancient Egyptians waited with baited breath for the return of the dog star. Around mid-July the star would rise just before dawn (heliacal rising.) This was the start of the Egyptian new year. Farmers knew the waters of the Nile would begin to rise and renew and replenish the fertile farmlands of the Nile valley.

For the Greeks and Romans, the dawn appearance of Sirius coincided with the hottest part of the summer. The theory was that the added heat and brightness of the dog star joined with the sun creating the hot, summer temperatures. Manilius, a Roman poet, wrote of Sirius: “It barks forth flame and doubles the burning heat of the sun.”

Sirius is the fifth closest star to our solar system. It is approximately 8.6 light years from earth. Most astronomers believe Sirius has a white-dwarf companion star, which orbits it every 50 years.

According to Polynesian legend, Sirius wasn’t always the brightest star in the night sky. That distinction belonged to another star in the area of the constellation we know as Taurus. The envious Sirius pleaded with the god Tane to rectify the situation. Tane, upon Sirius’ urging, hurled the star Aldebaran at this brilliant orb, shattering it into the faint fragments known as the Pleiades.

While almanacs mark Aug. 11 as the end of dies caniculus, the dog star will remain in the daytime skies for a few more months. In December Canis Major will once again join Orion to hunt the winter skies.

 

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The Smoky Mountain News