PG 1159 star

A PG 1159 star (aka pre-degenerate) is white dwarf coming into being (or a pre-white dwarf), having completed a planetary nebula phase. The term is coined from the first identified, PG 1159-035, which appears to have resumed helium burning but is expected to cool into a white dwarf. They are hot, in the 75,000-200,000 K and show an excess of ultraviolet. Some characteristics of PG 1159-035:

• 0.63 M_Sun.
• 0.0254 R_Sun.
• 200 L_Sun.
• 136,000 K - temperature.

This is exceptional for being both far smaller and far more luminous than the Sun.