FAINT OBJECT SPECTROGRAPH OBSERVATIONS OF MRK-509 - ULTRAVIOLET-ABSORPTION LINES NEAR THE REDSHIFT OF THE SEYFERT-GALAXY

Ultraviolet spectra of the Seyfert 1 galaxy Mrk 509 have been obtained with the Faint Object Spectrograph on the Hubble Space Telescope. The spectra show strong absorption lines in the cores of the redshifted e mission Lines of Ly alpha and C IV lambda lambda 1548.2, 1550.8, confi rming an earlier detection in IUE high-dispersion spectra, and a new d etection of strong N V lambda lambda 1238.8, 1242.8 absorption lines, also near the redshift of Mrk 509. There is no evidence for absorption in the Lines of Mg II or Si IV at the redshift of Mrk 509. The absorp tion lines have two components that are at the same velocities as thos e in the IUE observations obtained similar to 12 yr earlier: one at th e systemic redshift of the host galaxy, as defined by the low-ionizati on emission lines in the optical, and one at a radial velocity of -390 km s(-1) relative to the systemic redshift. The equivalent widths and velocities of the absorption lines indicate that they arise from an e xtended region of highly ionized gas surrounding the nucleus of the ho st galaxy consisting of two distinct kinematic components. (C) 1995 Am erican Astronomical Society.