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To understand the evolutionary stage of the peculiar supergiant IRC+10420, wehave been taking spectra for several years at the 6m telescope. The opticalspectrum of IRC+10420 of the years from 1992 through 1996 points to theincrease in the temperature: spectral class A5 instead of the former F8, as waspointed out by Humpreys et al., (1973). Now it resembles the spectra oflate-type B[e] stars. The spectrum contains absorptions (mainly of ions) formedin the photosphere, apparently stationary with respect to the star center ofmass, and emissions too, which can be formed in the fossil expanding envelopeas well as partly in its compressing region. Using our spectra and spectraldata obtained by Oudmaijer (1995) we estimated the atmospheric parametersTeff=8500 K, logg=1.0, Vt=12km/s and concluded that metallicity of IRC+10420 issolar: the average value [(V,Cr,Fe)/H]=-0.03. Combination of results allows usto consider IRC+10420 as a massive supergiant evolving to the WR-stage.Comment: 14 pages, Latex, 4 ps figures, uses supertab.sty. Accepted for  publication in the MNRA

Optical spectrum of the IR source IRC + 10420 in 1992-1996