FUSE Observations of the hottest DA white dwarfs

We report early FUSE observations of the very hot DA white dwarfs PG1342+444 and REJ0558-371. Detection of photospheric absorption lines allows us to estimate the abundances of C, O, Si, P, S and Fe, the first measurements reported for DA stars at such high temperatures. Values of Teff and log g determined for PG1342+444 from the Lyman line series disagree with the results of the standard Balmer line analysis, an issue that requires further investigation.