The ancient origins of the Dog Days of Summer

Originally written on July 2021, updated 2023

According to popular folklore:
“Dog Days bright and clear
Indicate a happy year;
But when accompanied by rain,
For better times, our hopes are vain.”

It sounds good…but what are the Dog Days of summer, exactly? And what do they have to do with dogs?
The exact dates of the Dog Days can vary from source to source and probably they have changed over time. However, most sources agree that they occur in mid- to late summer, from July 3 to August 11.
This is soon after the Summer Solstice in late June, which of course also indicates that the worst summer heat soon will come.
It is a time during which snakes are blind and will strike at anything, birds do not sing as much and, because these are the days of the year when there is less rainfall, wells may go dry. Insects are also said to be more plentiful and aggressive during these days.

The name “Dog Days” traditionally refers to a period of particularly hot and humid weather occurring during the summer months of July and August.
At least, in the Northern Hemisphere.
In any case, this period of sweltering weather coincides with the year’s heliacal (meaning literally “at sunrise”) rising of Sirius.
Sirius is part of the constellation Canis Majoris, literally the “Greater Dog”, which is where Sirius gets its nickname, Dog Star, as well as its official name, Alpha Canis Majoris.
Not including our Sun, Sirius is the brightest star in the sky and, under the right conditions, it can even be seen with the naked eye during the day.

For the ancient Egyptians, the dawn rising of Sirius also coincided the Nile River’s flood season, and they used the star as a “watchdog” for that event, usually beginning in late June.
There the Nile River flooded each year, and folks welcomed the inundation, as the floodwaters brought rich soil needed to grow crops in what was otherwise a desert.
No one in Egypt knew exactly when the event would start, but they noticed a pure coincidence: the water began to rise on the days when Sirius, known to them as “Sothis”, began to rise before the Sun.
Sothis and the Inundation became so important to their survival that they began their new year with the new Moon, that followed the star’s first appearance on the eastern horizon.

Unlike the Egyptians, the ancient Greeks and Romans were not as pleased by Sirius’s appearance.
For them, it signaled a time when evil was brought to their lands with drought, disease, and discomfort as dogs and men alike would be driven mad by the extreme heat.
According to the Roman poet Virgil, it “bringer of drought and plague to frail mortals, rises and saddens the sky with sinister light”, but he also noted vintners’ efforts to protect their work during the time “when the Dog-star cleaves the thirsty Ground”.
In the Roman Empire its presence was so ill-omened that hit men were sometimes employed to sacrifice dogs when the star appeared.
In short, the combined heat of super-bright Sirius and the Sun was thought to be the cause of summer’s sweltering temperatures.
The name itself, “Sirius”, come from Ancient Greek seírios, meaning, not by chance, “scorching.”
In fact, Seneca’s Oedipus complains of “the scorching dog-star’s fires”.
Luckily today they doesn’t conjure up such bad imagery, instead, the Dog Days are associated just with the time of summer’s peak temperatures and humidity.
Of course, we also know the appearance of Sirius does not affect seasonal weather at all here on Earth, but its appearance during the hottest part of summer ensures that the folklore surrounding the star lives also on modern times.

When all is said and done, to us, the phrase will always refer to those torturous, unbearable summer days, when the air is thick with heat, and the only thing that could possibly placate us is a big ol’ glass of beer or an icy bath somewhere in the mountains. That’s true, people?! Hang in there until August 12!

Images from web – Google Research