Herbig Ae/Be starA still-contracting (pre-main sequence) star of spectral type A or B, with strong emission lines (especially H-alpha and the calcium H and K lines), associated with fairly bright nebulosity; named after the American astronomer George Herbig (1920–) and also known as a Herbig-Bell star or a Herbig emission star. A well-known example is R Coronae Borealis (see R Coronae Borealis star. The number of Herbig Ae/Be stars is smaller than the number of T Tauri stars (lower mass pre-main-sequence stars), for two reasons: higher mass stars in general are less common, and also the timescale for the core contraction of Ae/Be stars is smaller than for stars of smaller mass, so they remain deeply embedded until the end of their mass accretion stage. Related entry• variable starsRelated category• TYPES OF STARAlso on this site: Encyclopedia of Alternative Energy & Sustainable Living Encyclopedia of History |