What is a planetary nebula?
A) Gas ejected from a low-mass star in the final stage of its life
B) Gas created from the remains of planets that once orbited a dead star
C) Interstellar gas from which planets are likely to form in the not-too-distant future
D) The remains of a high-mass star that has exploded

Question

Quizplus · Accepted Answer

A planetary nebula is formed when a low-mass star (like our Sun) begins to run out of fuel in its core. As the fuel runs out, the star expands and ejects its outer layers of gas, creating a glowing shell of gas and dust that surrounds the remaining core of the star. This shell is what we see as a planetary nebula. The name "planetary" nebula is actually a misnomer, as it has nothing to do with planets. The name comes from the fact that some of these nebulae have a round, planet-like appearance in early telescopes.

What Is a Planetary Nebula