The Holmium AP star HD 51418.

The peculiar A star RD 51418 differs from other Ap-type stars in that its spectrum is dominated by lines of the heavy rare earths, including particularly holmium and dysprosium. in this respect, the spectrum of RD 51418 closely resembles that of RD 101065 (Przybylski's star). The magnetic field of RD 51418 varies from + 750 to -200 gauss, and magnetic minimum coincides in phase with rare-earth minimum and with minimum light. The observed radial velocity variations give strong evidence that the spectrum variations can be accounted for by the oblique rotator model. Subject headings: magnetic stars - peculiar A stars - stars, individual