THE METHOD OF THE GALACTIC ROTATION DISTANCES

The method of galactic rotation distances is investigated by means of numerical simulations and found to work properly, even when the disper sion of the absolute magnitudes or the peculiar velocity dispersion ar e large. We apply the method to a large sample of more than 600 galact ic supergiants and bright giants. We derive average mean absolute magn itudes which confirm the average absolute magnitudes found by either B laauw or Schmidt-Kaler. Our calibration has the advantage to be based upon both a single method and a large number of stars. We show that th e method works properly only with large samples. Therefore no subdivis ions according to spectral types can be derived. We show further that the method is stable in the sense that small variations in the input p arameters produce only small changes in the results.