July 24, 2026, 3:54 am | Read time: 4 minutes
The term “dog days” refers to the period between July 23 and August 23. But do you know where the term comes from and what it has to do with our four-legged friends? PETBOOK has done the research for you.
When Are the Dog Days?
In Europe and North America, the dog days occur every year from July 23 to August 23 and are considered the hottest days of the year, as explained by our colleagues at myHOMEBOOK.
The dog days are also recognized in other European countries and languages:
- “dog days” in England
- “la canicule” in France
- “la canicola” in Italy
- “la canicula,” “periodo canicular,” “dias de la caniculas” in Spain
- “kanikuly” (translated: summer vacation) in Russia
Also interesting: 11 tips for helping dogs get through the summer
What Do the Dog Days Have to Do With Dogs?
The name suggests it comes from the hot summer period when our four-legged friends often suffer from the intense heat. But that’s far from the truth! The term “dog days” actually has its origins in astronomy and is derived from a star and its constellation.
The star Sirius, also known as the Dog Star, and its constellation “Canis Major” (the Great Dog) give this time of year its name, as they are only visible in the night sky during these days. Sirius is the brightest star in the constellation “Canis Major.”
The period from the appearance of the star Sirius to the full appearance of the constellation “Canis Major” falls precisely between July and August. Therefore, the term “dog days” is derived from “the days of the Great Dog.”
The origin of the name and the timing of the dog days date back to the Roman Empire. The term “dog days” can first be traced back to the Roman Kingdom era when the star Sirius rose on August 1 in 46 B.C. during the time of Julius Caesar in Rome and caught people’s attention.
Myths About the Dog Days
The Greeks explained the connection between the reappearance of the star Sirius and the peak summer heat through a myth. They attributed the heat during these days to the merging of the fire of the star Sirius with sunlight.
The appearance of a mirage during shimmering summer heat was later described by Arab astronomers as “the saliva of the Dog Star dripping from the sky.” This explained the optical illusions of the mirage.
The Egyptians saw the dog days as harbingers of a fertile period. When the constellation “Canis Major” appeared, the annual flooding of the Nile occurred, irrigating the surrounding land and making it more fertile.
From these ancient myths, numerous farmers’ sayings have emerged and survived to this day:
- “Dog days hot, bring the farmer a lot of sweat.”
- “As the weather when the Dog Star rises, so it will remain until it sets.”
- “If the dog days are hot, winter will stay white.”
- “Dog days bright and clear, indicate a good year – if they bring rain, the best times won’t appear.”
- “If the dog days are full of sunshine, the year will be quite fruitful.”
- “What the dog days pour, the grape must pay for.”
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The Current Meaning of the Dog Days
The shift in the Earth’s axis is the reason why the dog days have moved about four weeks later over the centuries. When Sirius appears around August 30 in modern times, it is already the first sign of the approaching autumn and no longer a harbinger of intense heat.
Due to old tradition, the period for the dog days in Germany has remained unchanged and signifies the hottest time of the year for many people.
Conclusion
Even though the dog days don’t really have anything to do with our four-legged friends, our dogs need special attention and care during the hottest time of the year. As the dog days approach, the term serves as a nice reminder for all pet owners to pay special attention to their dog’s needs during the coming weeks of intense heat.