Planetary Nebula Nucleus (PNN)
In 1995 the central planetary nebula nucleus (PNN) was observed as a DA white dwarf, having seemingly faded by a factor of three between 1987 and 1995. The PNN has an estimated mass of 0.6 M☉, and has an observed companion star separated by 0.3 arcsec. Nebula mass is estimated as 0.015 M☉.
Luminosity is estimated to be 3000 L☉. (Parthasarathy 2000)
Read more about this topic: Stingray Nebula
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