Nature 232, 178 - 179 (16 July 1971); doi:10.1038/232178a0

Rapid Optical Variability of the Source PKS 1514−24

F. BIRAUD^*

National Radio Astronomy Observatory, Green Bank, West Virginia
^*On leave from Département de Radioastronomie, Observatoire de Meudon, France.

THERE are two cases in which radio sources have been identified with optical objects previously known as variable stars: the Seyfert galaxy 3C120 with the star BW Tau (ref. 1) and VRO 42 22 01 with BL Lac (ref. 2). As a systematic search for possible new concidences, 807 variable stars were selected from the General Catalog of Variable Stars ³ and its first supplement⁴ using the following criteria: (i) type given as irregular or unknown; (ii) no spectral type given; and (iii) galactic latitude |b _I|>10°. This list was checked for coincidences against A Master List of Radio Sources ⁵ and the fourth instalment of the Ohio survey⁶. Only two coincidences were found.

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