Stellar Temperature Scales

The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.

Stellar Temperature Scales

 

relations between quantities obtained from observations characterizing the energy distribution in the spectrum of a star (spectral class, color index, and others) and the effective temperature. These relations are used when comparing the results of theoretical studies of stellar structure and evolution with observations.

In order to determine stellar temperature scales, it is necessary to know the linear dimensions of the star and the total quantity of energy radiated by it. These circumstances introduce difficulties in determining stellar temperature scales associated with the necessity of photometry of stars in the far ultraviolet and infrared regions of the spectrum and with the small number of stars of known radii (principally the closest stars—supergiants and eclipsing variable stars). In the same spectral class the dwarfs are hotter than the giants and supergiants, since, because of the lesser force of gravity on the surface of the last two, the same degree of ionization and excitation of the atoms, which determines the spectral class, is attained at a lesser temperature. Table 1 gives a stellar

Table 1. Stellar temperature scale
Spectral classEffective temperature (°K)
 DwarfsGiants
BO28,00021,000
B515,50011,500
AO98509400
FO70307500
GO59005800
KO52404900
MO37503750
M531002950
M82750 

temperature scale compiled on the basis of the data of the American astronomers H. Johnson (1966) and D. Morton and T. Adams (1968), which has been confirmed by the latest measurements.

IU. N. EFREMOV

The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.