A Multiwavelength Study of the Close Environment of HD 34078

We present super(12)CO(2-1) emission line observations of the region surrounding HD 34078, together with new optical and FUSE spectra of this runaway star. CO(2-1) emission peaks close to the star position and correlates well with IR thermal dust emission. Our follow-up of CH and CH super(+) optical absorption lines confirms the reality of marked time variations while FUSE spectra indicate no such changes for H sub(2). These results are consistent with a picture in which all absorption lines in HD 34078's spectrum originate from material located close to the star, in a dense inhomogeneous shell formed at the stellar wind/ambient cloud interface where CH and CH super(+) are overabundant.