Of stars

Of stars

(oh-eff ) Young massive O stars that show selectively enhanced emission lines of ionized helium (He II) and nitrogen (N III) in addition to a well-developed absorption spectrum. The emission lines arise in an unstable atmosphere that is being lost from the star. Of stars are the hottest, most luminous, and probably the most massive stars in the Galaxy: the record holder is HD 93129A, near Eta Carinae, with a temperature of 50 000 K, a luminosity of 3 million Suns, and a mass of probably 120 solar masses (see also supermassive stars). Of stars are thought to be the evolutionary precursors of Wolf-Rayet stars.