July 9, 2017 – Who Knew?

I like trivia – I always have. I also really like obscure facts. One such fact is why the period from July 3rd to August 11th each year is called the dog days of summer. The origin of the phrase dates to ancient Egypt when the Sun occupied the same region of the sky as Sirius, which the brightest star visible from any part of Earth during the period mentioned above.  Sirius is part of the constellation Canis Major, the Great Dog.

In the summer, Sirius rises and sets with the summer Sun. The Romans believed Sirius gave off heat and added to the Sun’s warmth, exacerbating  the long stretch of hot weather. The Romans referred to this time as, dies caniculares or “dog/puppy days.” Eventually the term Dog Days of Summer came to mean the 20 days before and 20 days after this alignment of Sirius with the Sun.  Typically (and coincidentally) this is the hottest part of summer. The phrase really took on new meaning during the Roman Warm period (250 BC to AD 400), which was a period of global warming when grapes were cultivated in Roman Britain and Greenland was actually green.

Let’s be glad it’s only 40 days – summer on Uranus lasts 21 years (whew!)


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