accretion disc
101Mercury-manganese star — A mercury manganese star is a type of chemically peculiar star with a prominent spectral line at 398.4 nm, due to absorption from ionized mercury.[1] These stars are of spectral type B8 or B9, with two distinctive characteristics: An atmospheric… …
102Am star — An Am star or metallic line star is a type of chemically peculiar star of spectral type A whose spectrum has strong and often variable absorption lines of metals such as zinc, strontium, zirconium, and barium, and deficiencies of others, such as… …
103Wolf–Rayet star — Hubble Space Telescope image of nebula M1 67 around Wolf–Rayet star WR 124 Wolf–Rayet stars (often referred to as WR stars) are evolved, massive stars (over 20 solar masses initially), which are losing mass rapidly by means of a very strong… …
104Color–color diagram — In astronomy, color–color diagrams are a means of comparing the apparent magnitudes of stars at different wavelengths. Astronomers typically observe at narrow bands around certain wavelengths, and objects observed will have different brightnesses …
105Hertzsprung–Russell diagram — Hertzsprung–Russell diagram[1] with 22,000 stars plotted from the Hipparcos catalog and 1,000 from the Gliese catalog of nearby stars. Stars tend to fall only into certain regions of the diagram. The most predominant is the diagonal, going from… …
106Dredge-up — refers to a period in the evolution of a star where a surface convection zone extends down to the layers where material has undergone nuclear fusion. As a result, the fusion products are mixed into the outer layers of the stellar atmosphere and… …
107List of proper names of stars — This is a list of proper names for stars, mostly derived from Arabic and Latin. See also the list of stars by constellation, which gives variant names, derivations, and magnitudes. Of the roughly 10,000 stars visible to the naked eye, only few… …
108North polar sequence — The North polar sequence is a group of 96 stars that was used to define stellar magnitudes and colors. The cluster of stars lies within two degrees of the Northern Celestial pole, which makes them visible to everyone on the northern hemisphere.… …
109O-type main-sequence star — Hertzsprung–Russell Diagram Spectral Type Bro …
110K-type main-sequence star — Hertzsprung–Russell Diagram Spectral Type Br …
