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physical object > natural object > celestial body > star > late star > M star

M star
subject			fact

M star	has definition Spectral type for red stars, such as Betelgeuse, Antares, and Proxima Centauri.
	has definition Star of spectral type M are cool red stars with surface temperatures of less than 3600 K whose spectra are dominated by molecular bands, especially those of TiO. M dwarfs are the most numerous type in our galaxy.
	has definition Having a spectral type of M, that is, red like Betelgeuse and Antares.
	is a kind of late star
late star	has spectral type cooler than G2
star	has star surface temperature
	has V magnitude
	has B magnitude
	has U magnitude
	has position on celestial sphere from the point of view of Earth
	has parallax from the point of view of Earth's orbit
	has proper motion
	has radiation at surface which is diffused out from the hotter core
	has energy source gravitational contraction and or fusion
	has energy production which takes place primarily within the core
	has surface density which depends on luminosity class
	has surface temperature greater than 1000 Kelvin
	has apparent magnitude
	has absolute magnitude
	has age
	has catalog star catalog
	has material hydrogen, helium
	has velocity determined from proper motion and radial velocity
	has mass greater than 0.08 the sun's mass
celestial body	has spectra
physical object	has location or center of gravity
	has angular momentum
	has momentum
	has temperature
	has volume
	has extent

Kinds of M star :

• Alpha Vulpeculae (10 facts) (HR 7405)
• Barnard's star (12 facts) - A faint binary star with the second largest proper motion known. Long-term observations of its light curve suggest a possible third component with a mass about 1.2 that of Jupiter, although this observation has been challenged.
• dMe star (1 kind, 16 facts) - M dwarf with hydrogen emission lines.
• Gamma Sagittae (10 facts) (HR 7635)
• Kapteyn's star (10 facts) (HD 33793, CD -45 1841) - A nearby high-velocity M0 subdwarf that is both the nearest halo star to the Sun and the nearest star that orbits the Galaxy backward.
• Kruger 60 AB (7 facts) - A faint dM binary in the Solar neighborhood. It may be a subluminous star.
• Me star (3 facts) - Star of spectral type M with emission lines in their spectra.
• MS star (3 facts) - Star sharing the M and S characteristics. They thus exhibit bands of both TiO and SrO., M-type stars with ZrO bands.
• NML Cygnus (10 facts) (IRC+40448) - An infrared star. Its surface temperature is about the same as the surface temperature of Venus. It is a strong OH emitter, and CO has been identified in its spectrum.
• red giant (1 kind, 20 facts) - Large, highly luminous but relatively cool star that has reached a late stage in its "life". It is running out of nuclear "fuel" and has accordingly expanded greatly and become less dense. Many also become variable stars of long periodicity. Its next evolutionary stage is to become a white dwarf, in developing into which the star has to cross the main sequence on the Hertzsprung-Russell diagram., A giant star with spectral type M. Such stars are in a more advanced state of evolution than the Sun, for they do not burn hydrogen into helium at their cores. Instead, they may fuse hydrogen into helium in a layer surrounding their cores, or they may fuse helium into carbon and oxygen, or they may do both. Often, astronomers use "red giant" loosely, to include not only M giants but G and K giants, too., A late-type (K or M) high-luminosity (brighter than M_v = 0) star that occupies the upper right portion of the H-R diagram. Red giants are post-main-sequence stars that have exhausted the nuclear fuel in their cores. The red-giant phase corresponds to the establishment of a deep convective envelope. Red giants in a globular cluster are about 3 times more luminous than RR Lyrae stars in the same cluster.

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