We’re in the thick of the ‘dog days of summer.’ We can thank the ancient Greeks for that
The dog days of summer, the period during which the star Sirius rises alongside the sun, run from July 3 to August 11. Ancient people believed that Sirius influenced the weather, among other phenomena, that caused particularly excruciating heat and even drove people and dogs to madness.
True, it is especially hot in the summer, but that’s not Sirius’ fault, William Cumiford, associate professor at Chapman University and ancient history scholar. Nor is it the fault of a star that heat can make humans and canines alike volatile.
But Sirius, known as the “dog star” to the ancient Greeks, did inspire the saying we still use today. Here’s how the “dog days of summer” went from a feared period in ancient Greece and Rome to an innocent phrase immortalized in film and song.
‘Dog days’ started with a star
It all starts with Sirius, the brightest star in the night sky and the part of the Canis Major that makes up the “snout” of the dog-shaped constellation. And adorably, Sirius seemed to be tailing a certain man-shaped set of stars.
“It seems that the star appeared to form a celestial canine apparition ‘following’ the constellation of Orion,” Cumiford said.
But with astronomy in its infancy and other fields of science still unexplored, people of ancient civilizations “looked to the heavens” to explain the seemingly inexplicable phenomena in their lives, from illness to extreme weather and other disasters, Cumiford said.
Enter Sirius. Ancient Egyptians believed that the star co-rising with the sun was related to annual Nile River flooding, Cumiford said. (The river floods annually because of heavy summer rainfall, not because Sirius and the sun cause it.)
But Sirius — or Sothis, to the Egyptians — wasn’t viewed as a destructive force in ancient Egypt, per the Old Farmer’s Almanac. The annual flooding brought silt and fertile soil to parts of the desert, an essential and life-sustaining tradition the Egyptians counted on every year.
The Greeks, meanwhile, who named Sirius, believed that Sirius and the sun shining brightly together contributed to the extreme heat of the late summer, said Cumiford. This belief made its way into one of the great Greek epic poems — Homer’s “Iliad,” which compares Achilles, the great Greek warrior of myth, and his shield to “the star they call Orion’s dog — brightest of all but a fatal sign emblazoned on the heavens, it brings such killing fever down on wretched men.”
The Romans, too, believed in the dangerous power of “the dog star.” In Virgil’s “Aeneid,” he writes, in one translation, of “fiery Sirius, bringer of drought and plague to frail mortals” and the way it “rises and saddens the sky with sinister light.”
Greeks and Romans also believed that Sirius influenced other weather events, including droughts and thunderstorms, along with poor health, bad luck — and dogs gone mad. The dog star and its seemingly destructive powers begat the phrase “dog days of summer.”
In extreme heat, dogs and humans alike suffer — they’re tired, overheated and in need of cool relief that may not come for months. And among humans, heat really can drive us mad: Research shows that higher temperatures are associated with anger, aggression and even acts of violence. And if we’re suffering in the heat, think of how dogs feel under all that fur.
But Sirius and the sun have little to do with each other or with us. Though it’s the brightest star in the night sky, Sirius has no effect on Earth’s weather or climate, Cumiford said.
‘Dog days’ in pop culture
The phrase “dog days” lived on long after the fall of the Roman Empire — and after we came to understand that Sirius does not cause madness in people or dogs. And the way we’ve come to understand it has changed, too: Now, it’s used more generally to refer to the unbearably hot, humid, overall unpleasant days of summer.
Charles Dickens used it, though, to express just how chilly and cruel his protagonist Ebenezer Scrooge could be to his underlings in “A Christmas Carol”: “He carried his own low temperatures always about with him; He iced his office in the dog-days, and didn’t thaw it one degree at Christmas.”
“Dog Day Afternoon,” the classic 1975 crime drama starring Al Pacino, takes place on an excruciatingly hot day in late August (although it’s set on August 22, 11 days after the “dog days of summer” are thought to end), Cumiford noted.
Sometimes “dog days” isn’t used to refer to the extreme heat of summer but any difficult period of despair. Florence and the Machine’s breakout single “Dog Days Are Over” is a celebration of coming out on the other side of a slump, reaccepting happiness after an emotional drought.
We’re around halfway through the dog days of summer if we’re going by the Old Farmer’s Almanac’s end date of August 11. But the heat persists all summer long — and it’s just hot enough these days to make you feel like you’re going a bit mad.
Despite the belief that Sirius, the "dog star," contributes to the extreme heat during the dog days of summer, William Cumiford, an associate professor, asserts that it's not the star's fault that humans and dogs can become volatile under the scorching temperatures.
The hot weather during the dog days of summer can have a significant impact on both humans and dogs, causing irritability and even leading to acts of violence, according to research.
