Hayashi track — The Hayashi track is a path taken by protostars in the Hertzsprung Russell diagram after the protostellar cloud has reached approximate hydrostatic equilibrium. In 1961 Chushiro Hayashi showed that there is a minimum effective temperature… … Wikipedia
Hertzsprung–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… … Wikipedia
Star formation — is the process by which dense parts of molecular clouds collapse into a ball of plasma to form a star. As a branch of astronomy star formation includes the study of the interstellar medium and giant molecular clouds as precursors to the star… … Wikipedia
Étoile de la pré-séquence principale — Une étoile de la pré séquence principale (ou pré série principale) est une étoile encore à un stade d évolution antérieur à celui de la séquence principale. Ce peut être une étoile T Tauri ou une étoile FU Orionis, dont la masse est inférieure à… … Wikipédia en Français
Stellar evolution — Life cycle of a Sun like star Stellar evolution is the process by which a star undergoes a sequence of radical changes during its lifetime. Depending on the mass of the star, this lifetime ranges from only a few million years (for the most… … Wikipedia
Main sequence — A Hertzsprung Russell diagram plots the actual brightness (or absolute magnitude) of a star against its color index (represented as B V). The main sequence is visible as a prominent diagonal band that runs from the upper left to the lower right.… … Wikipedia
Star — For other uses, see Star (disambiguation) … Wikipedia
Convection zone — An illustration of the structure of the Sun: 1. Core 2. Radiative zone 3. Convective zone 4. Photosphere 5. Chromosphere 6. Corona 7. Sunspot 8. Granules 9. Prominence … Wikipedia
List 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… … Wikipedia
Apparent magnitude — Asteroid 65 Cybele and 2 stars with their magnitudes labeled The apparent magnitude (m) of a celestial body is a measure of its brightness as seen by an observer on Earth, normalized to the value it would have in the absence of the atmosphere.… … Wikipedia
