X-Ray Discovery of a Hot PG1159 Star, RX J0122.9-7521

The supersoft X-ray source RX J0122.9-7521 has been optically identified with an extremeley hot PG1159 star. Its spectrum shows high excitation emission lines from which we estimate Teff ~140,000K and log g~7. Limited photometry taken during six nights shows no conclusive variability, but we cannot rule out short-period, low-amplitude pulsations (P<5 min) as are found in some PG1159 stars. There is some evidence for variations in the emission-line strengths, but higher quality spectra are needed to confirm this. (SECTION: Stars)