La variable de helio HD 125823

In part I the behavior of the spectrum between 1908 and 1986 is analysed. The spectral type varied between B2 V and B7 III. This object represents very probably a new type of variables. In part II it is shown, on the basis of 110 Å/mm spectrograms taken at La Plata, that the star varies in spectral type with a period of 8ᵈ8061. Possible mechanisms which might account for this variation are examined. The work reported here has meanwhile appeared in press in the Astrophysical Journal Letters (1968) and Nature 219, 1137 (1968).Asociación Argentina de Astronomí