Glossary term: M-type star

Also known as M star or M-star

Description: An M star is one whose "surface" temperature (the temperature of the layer in the star from which its light is emitted also known as effective temperature) is between 2500 and 3700 kelvins. An M star is identified by molecular absorbtion bands in its spectrum, primarily from titanium oxide. M stars appear red to the human eye when viewed through the Earth's atmosphere. Red dwarfs are spectral type M stars on the main sequence. Red giants and red supergiants are also mostly M stars.

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Term and definition status: This term and its definition is still awaiting approval

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