Gravities

Gravities for stars are derived from their spectral type and luminosity class. Calibrations are stored in files spec_logg.V, spec_logg.IV, spec_logg.III, spec_logg.II, spec_logg.I in oyster/starbase.

logg_stars Compute log(g) for all stars in startable.
logg_star(spectrum$<$_char$>$)

Function. Return log(g) for star with specified spectrum.