S-154 in the Large Magellanic Cloud - Spectral evolution from a luminous Fe II variable to a symbiotic-like star

The emission-line star, S-154, is a luminous variable in the Large Magellanic Cloud. Between 1988 February and December, S-154 changed its spectral appearance from a low-excitation «Fe II star» into a high-excitation state that resembles symbiotic stars. Before the transition (1984-1988), the spectral features had been primarily confined to emission lines of H and Fe II; afterward, we observed emission from He I, He II, O III, and the λ6830 band