A luminous giant star that has exhausted its core hydrogen. The outer layers expand and cool, giving a reddish appearance. The Sun will become a red giant in about 5 billion years, expanding to potentially engulf the inner planets.
A band on the Hertzsprung-Russell diagram representing stars fusing hydrogen into helium. Stars spend the majority of th...
A stellar core remnant of electron-degenerate matter, Earth-sized but with a mass comparable to the Sun. The final state...
A massive, luminous sphere of hot gas held together by gravity, generating energy through nuclear fusion. Stars range fr...
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