At this stage, the star becomes a large red giant ... Within this nebula, the hot core of the star remains—crushed to high density by gravity—as a white dwarf with temperatures over 180,000 ...

It turns out that one of the most prominent space artists predicted how a strange celestial object would look — 50 years in ...

Many a blue nebula has been discovered, shining by light from a hot blue star. If the reflection theory is correct, red nebulae should also exist, with comparatively cool red stars as illuminators.