Book chapters will be unavailable on Saturday 24th August between 8am-12pm BST. This is for essential maintenance which will provide improved performance going forwards. Please accept our apologies for any inconvenience caused.
PG1159-035 was originally detected as a 14.5 mag. blue object in a survey for QSO candidates (Green 1977), An SIT spectrogram obtained at the Hale 5m telescope at 6Å resolution showed this star to have a very blue continuum with absorption features near λ4686 and λ4650 which were tentatively attributed to Hell and the CIII/CIV complex, respectively. Possible narrow emission components to these lines appear in Figure 1 which shows confirming spectra obtained with the IIDS (at 2.5Å resolution) on the Kitt Peak 2.1m telescope. The blue continuum and possible presence of Hell in emission suggested that this star was perhaps similar to the helium mass-transfer binary AM CVn (HZ 29). For this reason, we put PG1159-035 on our program of high-speed photometry, expecting the star to show “flickering” associated with mass transfer into an accretion disk and possible orbital modulation or eclipses in the period range 10-20 minutes—photometric characteristics similar to those observed in AM CVn.