Procyon, brightest star in the northern constellation Canis Minor (Lesser Dog) and one of the brightest in the entire sky, with an apparent visual magnitude of 0.41. Procyon lies 11.4 light-years from Earth and is a visual binary, a bright yellow-white subgiant with a faint, white dwarf companion of about the 10th magnitude. The name apparently derives from Greek words for “before the dog,” in reference to the constellation.