THE EUVE AND IUE SPECTRA OF THE HOT DA WHITE-DWARF GD-659

We present recent EUVE spectra and new co-added IUE echelle spectra of the hot DA white dwarf GD 659. Our EUVE spectra show the expected con tinuum of a pure H DA white dwarf, from which we derive upper limits o n the photospheric abundances for He, C, N, O, and Si. Our co-added IU E echelle spectrum shows, in addition to the common interstellar lines , weak features due to C Iv, N v, and Si IV redshifted 72 km s(-1), wi th respect to the stellar photosphere. No features are seen at the exp ected stellar velocity. The lack of detectable absorption from strong subordinate lines of lower ionization states of C, N, and Si effective ly rules out a photospheric origin for the redshifted features. Instea d the redshifted features appear to arise in a highly ionized region e ither in the immediate circumstellar or interstellar environment of th e star. Our derived column densities for these species are compared wi th predictions for an interaction zone between a weak interstellar win d and an interstellar accretion how (MacDonald 1992) and with those of a Stromgren sphere (Dupree & Raymond 1983). These models prove inadeq uate to explain these observed ions. From our EUVE spectra we also obt ain interstellar column densities for H I, He I, and He II along the l ine of sight to GD 659. From these data we find respective interstella r H and He ionization fractions 0.36 +/- 0.17 amd 0.36 +/- 0.06.