LOCAL INTERSTELLAR-MEDIUM TOWARD BETA-GEM AND SIGMA-GEM

We present and analyze high-dispersion IUE observations of the interst ellar magnesium, deuterium and hydrogen absorption profiles toward two late-type stars beta Gem (10.8 pc) and sigma Gem (59 pc) separated by 0.5 degrees on the sky. We confirm the velocity shift of the local in terstellar cloud obtained for a bulk flow by Crutcher (1982). From the derived values of column densities of magnesium and deuterium we conc lude that the LISM in that direction extends not further than about 10 pc. We find the column density of deuterium equal to (4.7 +/- 1.5) x 10(-13) cm(-2) and an average HI density 0.075 cm(-3) less than or equ al to n(HI) less than or equal to 0.107 cm(-3). Abundance of the magne sium is about 1.1 dex smaller than the solar value.