Luminosity classification of red stars and distances to nearby red dwarfs
This investigation in the 24 Kapteyn Selected Areas along the celestial equator examined 21 red dwarf stars identified in an objective-prism survey. These stars were classified as red dwarf stars using light at wavelengths between 5800 A and 6800 A. Using calcium-hydride-based luminosity classification, this study found 13 of these stars to be red giant stars, and only 6 stars were found to be red dwarfs. One star was determined to be warm star. One star was not clearly distinguishable as a dwarf or giant. Distance calculations for the red dwarf stars found that these stars lie within 40 parsecs of the sun.