GALEX DISCOVERY OF A DAMPED Lyα SYSTEM AT REDSHIFT z ≈ 1

We report the first discovery of a QSO damped Lya system (DLA) by the Galaxy Evolution Explorer (GALEX) satellite. The system was initially identified as an Mgii absorption- line system (z(abs) = 1.028) in the spectrum of Sloan Digital Sky Survey (SDSS) QSO J0203-0910 (z(em) = 1.58). The presence of unusually strong absorption due to metal lines of Zn II, Cr II, Mn II, and Fe ii clearly suggested that it might be a DLA with N(H) (I) >= 2 x 10(20) atoms cm(-2). Follow- up GALEX NUV grism spectroscopy confirms that the system exhibits a DLA absorption line, with a measured H I column density of N(H) (I) = 1.50 +/- 0.45 x 10(21) atoms cm(-2). By combining the GALEX N(H) (I) determination with the SDSS spectrum measurements of unsaturated metal-line absorption due to Zn II, which is generally not depleted onto grains, we find that the system's neutral-gas-phase metal abundance is [Zn/H] = -0.70 +/- 0.22, or approximate to 20% solar. By way of comparison, although this system has one of the largest Zn(+) column densities, its metal abundances are comparable to other DLAs at z approximate to 1. Measurements of the abundances of Cr, Fe, and Mn help to further pin down the evolutionary state of the absorber.