This page contains explanations for words I found in my astronomy book that I didn't know before hand
Circumpolar; denotes a constellation which is visible year round.
Emission Nebula: a nebula which emits light rays.
Extrasolar Planets; Planets existing outside of our own solar system.
RedGiant; The stage in a star's life when it expands to nearly 100X's its original size and becomes very cool.
Vareiable
Star: Any star whose luminoscity changes over a short period of time.
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