Canis Major
Canis Major contains Sirius, the brightest star in the night sky, known as the "dog star". It is bright because of its proximity to the Solar System. In contrast, the other bright stars of the constellation are stars of great distance and high luminosity. At magnitude 1.5, Epsilon Canis Majoris (Adhara) is 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, blue-white supergiants Eta (Aludra) at 2.4 and Omicron at 3.0, and white spectroscopic binary Zeta (Furud), also at 3.0. 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.
NR Canis Majoris
NR Canis Majoris will eventually become the brightest star in the sky 2.6 million years from now to 3 million years from now, one of 4 different stars in Canis Major to hold that title (Alpha Canis Majoris, Beta Canis Majoris, and Epsilon Canis Majoris). During this period, NR Canis Majoris will be only 14 light years away and appear at -0.88 magnitude, about the same as Canopus today.