Why are emission nebulae associated with young stars?
A)Young stars have not moved far from the gaseous nebulae where they were born.
B)Only hot stars can ionize nearby gas; hot stars are high-mass, so must be young.
C)The dust that makes emission nebulae glow is destroyed by old stars.
D)Young stars produce the blue light that is scattered by emission nebulae.

Question

Quizplus · Accepted Answer

Emission nebulae are created when nearby gas is ionized by the intense radiation of hot stars. These hot stars are typically young because they are high mass and burn through their fuel quickly, so they don't live very long. Therefore, emission nebulae are generally associated with young stars.

Why Are Emission Nebulae Associated with Young Stars