We have analysed the absolute magnitude of about one hundrerd MK standards in the B0-F5 spectral region. We conclude that there is no strict relation between luminosity class and absolute magnitude, because in a number of cases inversions in absolute magnitude appear (for instance dwarfs brighter than giants). We also show that the new system of standards of Gray and Garrison shows the same effects.
We conclude that the relation between absolute magnitude and luminosity class is only a statistical one, which has a large intrinsic dispersion. It would seem advisable to eliminate some of the standards which cause problems.
© European Southern Observatory (ESO) 1998
Online publication: January 16, 1998