Influence of rotational darkening on ultraviolet interstellar extinction.

The influence of rotational darkening on ultraviolet stellar fluxes of fast rotating stars has been rediscussed. For this aim ANS filter-photometric magnitudes of weakly reddened B stars were corrected for interstellar extinction. The distribution of the stars in the rotational velocity-color index diagrams displays a scatter exceeding the photometric errors. The distributions of the stars agree qualitatively with the theoretically calculated color indices. The effect of rotational darkening should be taken into account as a possible source of individual deviations of the interstellar extinction from the average law.