RECENT CHANGES IN THE IUE SPECTRUM OF THE VERY YOUNG PLANETARY-NEBULAHE-3-1357 (=SAO-244567)

We obtained the first high-dispersion IUE spectrum, and an additional low-dispersion spectrum, of the very young planetary nebula He 3-1357 and its central star SAO 244567. In 1988, it showed a very strong C IV lambda 1549 P Cygni profile which diminished and has disappeared by 1 994, but C IV absorptions are seen in a high-resolution spectrum. The electron density from the C III] F(lambda 1907)/F(lambda 1909) emissio n ratio is log N-e = 4.1 cm(-3). The older IUE data were reprocessed, and emission-line fluxes vary greatly for the period 1988-1994. The hi gh-dispersion data show a rich Fe V and Fe VI absorption spectrum.