giant star

Star with a relatively large radius for its mass and temperature; this yields a large radiating area, so such stars are bright. Subclasses include supergiant stars, red giants (with low temperatures, but very bright), and subgiants (with slightly reduced radii and brightness). Some giants are hundreds of thousands of times brighter than the Sun. Giants and supergiants may have masses 10–30 times that of the Sun and volumes millions of times greater and are thus low-density stars.

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