The brightest of all stars shines prominently this week at around 10:30 p.m. local time over toward the south. Sirius, the “Dog Star,” is the brightest star of the constellation which bears the Latin name Canis Major—the Greater Dog.
In color, the star is a brilliant white with a definite tinge of blue, but when the air is unsteady it seems to flicker with all the colors of the rainbow. Seeing it in the sky will almost certainly remind you of the poem Twinkle Twinkle Little Star.
At a distance of 8.7 light-years, Sirius is the fifth nearest star known. Among the naked-eye stars it is the nearest of all, with the exception of Alpha Centauri. Four thousand years ago, ancient Egyptians noticed that Sirius would rise just before dawn at the time of the summer solstice, apparently heralding the coming rise of the Nile, upon which Egyptian agriculture — and all life in Egypt — depended. Hence, Sirius also became known as the “Nile Star.”
How Do I Locate Sirius?
Locating Sirius is easy! Just find the most recognizable constellations in the winter sky — Orion. Follow the three stars of Orions Belt straight down to Sirius, which will be unmistakable and bright.
Joe Rao is an esteemed astronomer who writes for Space.com, Sky & Telescope, and Natural History Magazine. Mr. Rao is a regular contributor to the Farmers' Almanac and serves as an associate lecturer for the Hayden Planetarium in New York City.