This is the last week of the Dog Days of Summer, marking the end of the reign of Sirius and the constellation called “Canis Major.”
The constellation Canis Major contains the star called “Alpha Canis” or “Sirius,” from the Greek, Seirios, meaning “scorching,” because it shines during the heat of summer.
Did you ever wonder what makes the constellation called “Canis Major,” or “the big dog” so big? The constellation itself isn’t particularly large. To answer the question, let’s take a closer look at Sirius.
What makes Sirius major is the light: it’s a first magnitude binary star, magnitude -1.5 on the Hertzsprung-Russell diagram. It’s brighter than any other star in the sky as well as most planets, outshone only by Venus and Jupiter. So, to us, the star itself looks big indeed.
Incidentally, in the constellation Canis Major, the brightest star is, of course, the nose.
Keeping watching! On August 24th, the official end of Dog Days, The Gloria Sirens will publish an array of dog- and animal-related stories, essays, and poems for your Sunday summer reading pleasure. How lonely we would be on this planet without them!