Well, we could change Grannus' color to match its type, or we could change its type to match its color, or we could do some combination of both.  At its current color, it would probably actually be a brown dwarf.  If we want to keep it a M2 red dwarf, it would be a lighter orange.  The chart provided by MaxL_1023 is a pretty good guide (current temperature = 3550 K). That's the color it would appear from a distance.  Up close it would probably look white to the human eye.  This is beca