Dog Days of Summer (Origin)

by Craig Shrives

What Is the Origin of the Saying "Dog Days of Summer"?

The term "dog days of summer" means the hottest days of the summer season. In the Northern Hemisphere, they run from July to August.
Dog Days of Summer (Origin)
The saying "dog days of summer" has nothing to do with dogs lazing around on a hot summer's day. It has nothing to do with dogs at all. The term has its origins in ancient Rome, when hot summer days were called "dog days" (dies caniculares). The name derives from the star Sirius, which, being the brightest star in Canis Major (Large Dog) constellation, was known as the "Dog Star."

Sirius is, in fact, the brightest star in the entire night sky, and the ancient Romans believed that it, as well as the Sun, radiated heat towards Earth. They believed that the heat of summer was caused by Sirius and the Sun rising and setting in unison, which occurs in the summer months. (Of course, the seasons are caused by the tilt of the Earth, not the alignment of the Sun with any stars, so the "dog days" of summer depend on your location.)

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