Astronomy and Space

A-type main-sequence star

An A-type main-sequence star is a main-sequence (core hydrogen burning) star of spectral type A. The spectral luminosity class is V. These stars have spectra defined by strong hydrogen Balmer absorption lines. They usually measure between 1.7 and 2.1 solar masses (M☉), have surface temperatures between 7,600 and 10,000 K, and live for about a quarter of the lifetime of the Sun. Bright and nearby examples are Altair (A7), Sirius A (A1) and Vega (A0). A-type stars do not have convective zones and thus are not expected to harbor magnetic dynamos. As a consequence, because they do not have strong stellar winds; they lack a means to generate X-ray emission.

Also on this shelf

See also

• ▸Aries (constellation)
• ▸James the Greater Church
• ▸49 Orionis

Uncatalogued shelf

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