HD 183125

Photometric observations of RR Lyrae covering half a century 4403 photographic observations obtained in the years 1943-1950, 2611white light observations from the years 1550-1957, altogether 31794 UBVobservations collected in the years 1958-1981 and 7135 observations madein the Stromgren uvby and Hβ wide/narrow band photometric systembetween 1990 and 1993 are published,
The visual surface brightness relation and the absolute magnitudes of RR Lyrae stars. II - RR Lyrae and X ARIETIS The theoretical surface brightness relation for RR Lyrae stars has beencombined with new VR photometry to determine distances, radii, andabsolute magnitudes for X Arietis and RR Lyrae. For X Arietis, apulsational variation in the radius from 5.06 solar radii to 5.96 solarradii, a distance of 495 + or - 50 pc, and an intensity mean absolutemagnitude of +0.59 + or - 0.25 is obtained. The corresponding quantitiesfor RR Lyrae are 4.81-5.67 solar radii, 263 + or - 39 pc, and anintensity mean absolute magnitude of +0.61 + or - 0.35. The largererrors quoted for RR Lyrae are due to uncertainties arising from theBlazhko effect. Results are discussed in the context of the dependenceof RR Lyrae absolute magnitudes on metal abundance.
Photoelectric Observations of Rr-Lyrae in 1975 Not Available
Photo-electric observations of RR Lyrae (Errata: 11 270) Not Available

INHABITED SKY