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A star whose spectrum shows strong hydrogen Balmer lines accompanied by many faint
to moderately strong metallic lines. In contrast to B and O stars, the lines of He
I and He II are absent. Their surface temperature ranges from 7,500 to 10,000 K. The
main metallic lines seen in A-type stars are those of Fe I and Fe II, Cr I and II,
Ti I and II, and account for about two-thirds of all lines. Some famous examples of
A star are Sirius, Deneb, Altair, and Vega. Also known as A-type star.
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