A cool, faint, low-mass star lying at the lower end of the main sequence. Red dwarfs have masses and diameters less than half those of the Sun. They are red because of their low surface temperatures, less than 4000 K, and are of spectral type K or M. Red dwarfs are the most common type of star, and also the longest-lived, with potential lifetimes greater than the current age of the Universe. Because of their low luminosity, no more than 10% of the Sun's, they are inconspicuous. Barnard's Star and Proxima Centauri are nearby examples. Many red dwarfs are flare stars.
Subjects: Astronomy and Astrophysics — Physics.