IS THE GALACTIC HALO PLANETARY-NEBULA PN G243-37.1 AN O-VI SEQUENCE VARIABLE OBJECT

Archival IUE spectra of the Galactic halo planetary nebula PN G243 - 3 7.1 have been reprocessed by the NEWSIPS routine. The new results show a much richer emission-line spectrum than has previously been reporte d. Several C III, C IV, O V, and possibly O VI features were detected. P Cygni line profiles could not be identified with certainty. The He II lambda 1640 emission, which is the strongest line in the IUE spectr um and is likely a mixture of stellar and nebular origin, increased in intensity as did the stellar continuum level between observational ep ochs of 1988 and 1990, which suggests that the object is a variable pl anetary nebula. A very recent optical spectrum confirms the UV results and suggests that the object underwent a dramatic change, possibly as a result of an episodic mass-loss event.