JACKSONVILLE, Fla. — It is a common misconception that the dog days of summer are when the weather is so hot that it's unfit for dogs.
The dog days of summer actually have to do with a star.
The dog days of summer are a 40-day period from July 3-Aug. 11. So, they do fall on what's typically the hottest and most humid part of the year.
It is at this time the dog star, Sirius, rises and sets with the sun.
The dog star is part of the Canis Major constellation, which roughly translates to "greater dog." The dog star is the "nose" of the dog shaped constellation.
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The star is so bright, that the ancient Romans and Greeks thought it also gave off heat, therefore adding to the warmth and making it the hottest part of the year.
Romans called these hot days the "days of the dog star," which evolved into "dog days."
Of course, the dog star doesn't actually to our warmth. It is the hottest part of the year because of the tilt of the earth. The sun's rays are able to hit the northern hemisphere more directly and for a longer period of time.
Because of the wobble in Earth's rotation, the rising of the dog star occurs several weeks later than when the Romans reported seeing it, which was closer to the summer solstice.
As it continues to wobble, in 10,000 years, the dog days will occur in winter.