The Winter Hexagon is an asterism appearing in the form of a large irregular hexagon with vertices at Rigel, Aldebaran, Capella, Pollux, Procyon, and Sirius. It lies predominantly in the northern celestial sphere.
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Near the equator, the asterism is visible in the evening sky from approximately December to June, and in the morning sky from July to late November. With increasing latitude, its visibility becomes progressively more restricted, as the stars remain lower above the horizon and are observable for shorter portions of the night. In the tropics and the southern hemisphere, where it appears during the local summer, this asterism (then called the "summer hexagon") can be extended southward with the bright star Canopus.
Smaller and more regularly shaped is the Winter Triangle, an approximately equilateral triangle that shares two vertices (Sirius and Procyon) with this winter hexagon asterism. The third vertex is Betelgeuse, which lies near the center of the hexagon. These three stars are three of the ten brightest objects, as viewed from Earth, outside the Solar System. Betelgeuse is also particularly easy to locate, being a shoulder of Orion, which assists stargazers in finding the triangle. Once the triangle is located, the larger hexagon may then be found.
The stars in the hexagon are parts of six constellations. Counter-clockwise around the hexagon, starting with Rigel, these are Orion, Taurus, Auriga, Gemini, Canis Minor, and Canis Major. Several of the stars in the hexagon can also be found independently by following various lines traced through the stars in Orion.