Asked by: Augustus Boelcke
science space and astronomy

What is a star's luminosity class related to?

Last Updated: 16th January, 2020

In the MK system, a luminosity class is added to the spectral class using Roman numerals. This is based on the width of certain absorption lines in the star's spectrum, which vary with the density of the atmosphere and so distinguish giant stars from dwarfs.

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Then, what is a star's luminosity class?

Luminosity classes are labeled with Roman numerals from I to V: I are supergiant stars, II are bright giants, III are ordinary giants, IV are subgiants, and V are ordinary main sequence stars. The complete spectral classification for a star is then given by specifying both the spectral class and the luminosity class.

Likewise, what is the spectral type and luminosity class of the sun? 1 L☉

Additionally, what is a star's luminosity quizlet?

luminosity- The luminosity of a star is the amount of light it emits from its surface. apparent brightness-how bright the star appears to a detector here on Earth. The difference between luminosity and apparent brightness depends on distance.

What does g2v mean?

In Sun. … Sun is classified as a G2 V star, with G2 standing for the second hottest stars of the yellow G class—of surface temperature about 5,800 kelvins (K)—and the V representing a main sequence, or dwarf, star, the typical star for this temperature class. (G stars are so called because of…

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