Have you ever heard someone say, "Ugh, we're in the dog days of summer now"?

The dog days are those long languid periods in July and August where the nighttime is hot and the daytime is even hotter.

But why dog days?

Well, you might think it's because it's so hot you start panting like a puppy.

But the answer has nothing to do, as it turns out, with actual dogs.

To find out why they're called the dog days, we actually have to leave the Earth.

If you wanna get all technical about it, the dog days start on July 3rd and last until August 11th.

This is also, on average, the hottest and muggiest time of the year in the Northern Hemisphere.

Around this time of year, a star called Sirius rises just before dawn in the eastern sky.

Sirius is the brightest star in a constellation known as Canis Major, the greater dog.

Canis Major rises just after another constellation called Orion the Hunter, and Sirius is Orion's loyal dog according to celestial legend.

For much of the spring and early summer, Sirius rises too late to be visible in the sky at all.

It's washed out by the sun.

But around the beginning of August, it starts to be visible again, rising just before dawn.

In ancient times, some people believed this star had something to do with the increased heat and even weather events.

The ancient Greeks saw a connection with the stickiest, most unpleasant time of the year, and the ancient Egyptians associated it with the annual flooding of the Nile River.

Today, we know that sta doesn't actually influence our weather, but the association between Sirius, the Dog Star, and heat waves in July and August has stuck, so we call them the dog days.

And you know what a dog really likes?

A nice nap in the summer sun.

So if we're gonna call them the dog days, might as well act like a dog!

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