冬季六边形也称为冬季大椭圆是一个看起来是六边形的星群，在六个顶点上分别是猎户座的参宿七、金牛座的毕宿五、御夫座的五车二、双子座的北河三（跳过北河二）、小犬座的南河三与大犬座的天狼星。虽然主要的天体都在北半球，但是几乎在地球上所有的陆地上都能看见（除了新西兰的南岛，南美洲的智利和阿根廷最南边）这个星群在每年的12月至3月在天空中闪耀着。在热带和南半球（称呼这个星群为「夏季六边形」或「夏季大椭圆」）还可以延伸至更南边的老人星。

The Winter Hexagon or Winter Circle/Oval is an asterism appearing to be in the form of a hexagon with vertices at Rigel, Aldebaran, Capella, Pollux, Procyon, and Sirius. It is mostly upon the Northern Hemisphere's celestial sphere. On most locations on Earth (except the South Island of New Zealand and the south of Chile and Argentina and further south), this asterism is prominently in the sky from approximately December to March. In the tropics and southern hemisphere, this (then called "summer hexagon") can be extended with the bright star Canopus in the south.