1879 20160701171654.0 ASTROimport-36 van Genderen, A. M. 1995 A pulsating star inside η Carinae. I. Light variations, 1992-1994. We present and analyze two seasons of intense photometric monitoring in the Stroemgren uvbyHß system of η Carinae (October 1992-August 1994). The luminous blue variable (LBV) in the core did not show much S Dor activity, i.e. it was in a relatively quiescent stage. This situation was very favourable for studying its optical micro variations. It appears that the central LBV pulsates (presumably in a non-radial mode) like other massive evolved stars, the a Cyg variables. The quasi-period is 58.56d. The linear ephemeris is: JD_max_ = 2448875.0 +58.56 E. Support was found for the existence of the presumed periodicity of 52.4d of the so-called "dimples", shallow dips in the light curve which only last for a few days. The cause may be the eclipse of a small companion or of a hot spot in an accretion disk. The Hß index became bluer by ~0.07mag during the last 11/2 years and shows an oscillation in anti-phase with the 58.56d pulsation, suggesting that the HII region(s) responsible for the hydrogen line emission has a relatively high luminosity. This is another reason to suppose that a second luminous source, perhaps a luminous disk (with a hot spot), may be present in the η Car system. Sterken, C. de Groot, M. Stahl, O. Andersen, J. Andersen, M. I. Caldwell, J. A. R. Casey, B. Clement, R. Corradi, W. J. B. Cuypers, J. Debehogne, H. Garcia de Maria, J. M. Jonch-Sorensen, H. Vaz, L. P. R. Stefl, S. Suso Lopez, J. Beele, D. Eggenkamp, I. M. M. G. Goecking, K.-D. Jorissen, A. de Koff, S. Kuss, C. Schoenmakers, A. P. Vink, J. Waelde, E. Astronomy and Astrophysics 304 1995 415 http://esoads.eso.org/abs/1995A%26A...304..415V published in REFERD