Procyon (α CMi / α Canis Minoris / Alpha Canis Minoris) is the brightest star in the constellation Canis Minor. To the naked eye, it appears to be a single star, the eighth brightest in the night sky with a visual apparent magnitude of 0.34. It is actually a binary star system, consisting of a white main sequence star of spectral type F5 IV-V, named Procyon A, and a faint white dwarf companion of spectral type DA, named Procyon B. The reason for its brightness is not its intrinsic luminosity but its closeness to the Sun; at a distance of 3.5 pc or 11.41 light years, Procyon is one of our near neighbours. Its closest neighbour is Luyten's star, 0.34 pc or 1.11 ly away. Procyon forms one of the three vertices of the Winter Triangle, along with Sirius and Betelgeuse.