We present a new analysis of the diffuse gas in the Magellanic Bridge ( RA \gtrsim 3 ^ { h } ) based on HST /STIS E140M and FUSE spectra of 2 early-type stars lying within the Bridge and a QSO behind it .
We derive the column densities of H I ( from Ly \alpha ) , N I , O I , Ar I , Si II , S II , and Fe II of the gas in the Bridge .
Using the atomic species , we determine the first gas-phase metallicity of the Magellanic Bridge , [ { Z / H } ] = -1.02 \pm 0.07 toward one sightline , and -1.7 < [ { Z / H } ] < -0.9 toward the other one , a factor 2 or more smaller than the present-day SMC metallicity .
Using the metallicity and N ( H I ) , we show that the Bridge gas along our three lines of sight is \sim 70–90 % ionized , despite high H I columns , \log N ( H I ) \simeq 19.6 –20.1 .
Possible sources for the ongoing ionization are certainly the hot stars within the Bridge , hot gas ( revealed by O VI absorption ) , and leaking photons from the SMC and LMC .
From the analysis of C II * , we deduce that the overall density of the Bridge must be low ( < 0.03 –0.1 cm ^ { -3 } ) .
We argue that our findings combined with other recent observational results should motivate new models of the evolution of the SMC-LMC-Galaxy system .