A-type Main Sequence Star

A-type Main Sequence Star

An A-type main-sequence star (A V) or A dwarf star is a main-sequence (hydrogen-burning) star of spectral type A and luminosity class V. These stars have spectra which are defined by strong hydrogen Balmer absorption lines . They have masses from 1.4 to 2.1 times the mass of the Sun and surface temperatures between 7,600 and 10,000 K. Bright and nearby examples are Altair (A7 V), Sirius A (A1 V), and Vega (A0 V).

Read more about A-type Main Sequence Star:  Spectral Standard Stars, Planets

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