What Is a Planetary Nebula

question 60

Multiple Choice

What is a planetary nebula?

• A)a disk of gas surrounding a protostar that may form into planets
• B)what is left of the planets around a star after a low-mass star has ended its life
• C)the expanding shell of gas that is no longer gravitationally held to the remnant of a low-mass star
• D)the molecular cloud from which protostars form
• E)the expanding shell of gas that is left when a white dwarf explodes as a supernova

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Definitions:

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