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The Great Dog of Winter Is a Beacon in the Night Sky

Even where light pollution shrouds most constellations from view, Sirius—the brightest star in our night sky—is especially visible in winter.
Field of stars in the night sky. The three brightest form a triangle to the left of the constellation Orion.
The Winter Triangle with Sirius at the bottom, Procyon at the top left, Betelgeuse at the top right, and Orion at the right (via Hubble European Space Agency)

Even in New York where light pollution can shroud the constellations from view, Sirius—the brightest star in our night sky—can still be witnessed. Part of the Canis Major constellation, it is especially visible in winter. It is close for a star—8.6 light-years away—but an unfathomable distance for us to travel through anything other than sight. It is brighter than our sun and twice as big. Its light is reinforced by a second, less visible white dwarf star, known as “the Pup” which is about the size of Earth but incredibly dense. It was once brighter than it appears now, but it has collapsed, as all stars will, including someday our own life-giving sun. The powerful brightness of Sirius (and its closeness to our Northern Hemisphere horizon) gives it an extra twinkling effect, causing it to seemingly change color as its light shines through our atmosphere.

In the coldest months of the year, the stars appear at their brightest. The dry air clears our view to the glimmering array of clustering stars visible in the winter months from the Northern Hemisphere. These include the three glowing points of the Winter Triangle: Betelgeuse blazing on the celestial warrior Orion; Sirius, the gleam adorning the eye of his hunting dog Canis Major; and Procyon, a spark in the smaller Canis Minor.

There is nothing more tempting than to spend all the darkest nights at home, listening to the radiators gently rattle as they fill the rooms with heat or letting a cat cozily curl its body on your lap. The length of the night feels endless, yet in it is opportunity. Take an evening to wear your warmest clothes and go somewhere you can see the sky; by the water or somewhere elevated is best. At first, you may not see much and the blare of the city can be distracting with its skyscrapers and street lamps and headlights. Calm your mind and look up into the sky whose limit is unknown. Find Sirius by following the line of Orion’s Belt down towards the horizon. There it is, blue-white in color and radiantly burning. There you are, letting the cold slip away for a moment and connecting with that beacon of light in the darkness.

Astronomical chart showing a strange whale, a harp, chemical apparatus, a mechanical device, and a table on which is a bust and sculpting tools forming the constellations.
Until the 1930 standardization by the International Astronomical Union, constellation naming was chaos, resulting in many now-obsolete monikers.The Machina Electrica, for example, celebrated the first electricity generator and is depicted in this 1825 chart below the constellation Cetus (via Library of Congress)