HST/COS DETECTION OF DEUTERATED MOLECULAR HYDROGEN IN A DAMPED Lyα SYSTEM AT z = 0.18Based on observations made with the NASA/ESA Hubble Space Telescope, obtained from the Data Archive at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555. These observations are associated with program #12204.