What is a Nebula? Nebula: Definition, Location and Variants - Space.com

Nebula are giant clouds of interstellar gas that play a key role in the life-cycle of stars.

Nebula is a Latin word meaning "cloud", but in an astronomical context, it refers to any celestial object which appears cloud-like when viewed through a telescope. When telescopes weren’t as powerfu… [+6969 chars]

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