Spectral Sequence of Stars

 
  400   500   600   700 nm
MK
Types

O5V
B1V
A1V
F3V
G2V
K0V
M0V

Note: The label colors don't correspond the the average star color, they represent the part of the spectrum which dominates.

Spectral
Type
Typical
Star
O5VHD242908
B1VHD35215
A1VHD116608
F3VHZ948
G2VHD66171
K0VHD23524
M0VHD260655
(view entire data base)

Features which are easily seen in the spectra classes image :

  1. The spectra of the hottest stars are more intense in the blue part of the spectrum.
  2. Cooler spectral types are brighter in the red part of the spectrum.
  3. Hydrogen absorption lines are seen in hotter spectral types.
  4. Hydrogen lines are most intense in the A1V type star.
  5. The following hydrogen absorption lines are visible :
Wavelength
nm
Absorption
line
656.3Hydrogen alpha
486.1Hydrogen beta
434.1Hydrogen gamma
410.2Hydrogen delta
397.0Hydrogen epsilon
388.9Hydrogen zeta
383.5Hydrogen eta
Sodium and calcium lines are visible in cooler spectral types
396.8Calcium II H line purple
393.4Calcium II K line purple
589.0Sodium I D doublet line strong in M type.
589.6Sodium I D doublet line strong in M type.

This research has made use of the Astronomical Data Center (ADC) at NASA Goddard Space Flight Center Catalog 3092

The publication containing this data is Jacoby et al. (1984)

For more information consult the spectral data reference page