Wikipedia:Today's featured article/January 4, 2015

Canis Major as depicted in Urania's Mirror, 1825

Canis Major (greater dog in Latin) is a constellation in the southern hemisphere's summer sky and northern hemisphere's winter sky. In the second century, it was included in Ptolemy's 48 constellations, and is counted among the 88 modern constellations. Along with Canis Minor (lesser dog), it is commonly represented as following the constellation of Orion the Hunter through the skies. The Milky Way passes through Canis Major. Several open clusters lie within its borders, including M41, which covers an area around the same size as the full moon. Sirius, also called the dog star, is the brightest star in the night sky, and one of the closest stars to Earth. The other bright stars in the constellation are much farther away but very luminous. At magnitude 1.5, Epsilon Canis Majoris (Adhara) appears as the second brightest star of the constellation and the brightest source of extreme ultraviolet radiation in the night sky. Next in brightness are the yellow-white supergiant Delta (Wezen) at 1.8, the blue-white giant Beta (Mirzam) at 2.0, and the blue-white supergiant Eta (Aludra) at 2.4. The red hypergiant VY Canis Majoris is one of the largest stars known, while the neutron star RX J0720.4-3125 has a radius of a mere 5 km. (Full article...)

Recently featured: Oliver Bosbyshell – Michael Tippett – 1924 Rose Bowl