A massive, luminous sphere of hot gas held together by gravity, generating energy through nuclear fusion. Stars range from red dwarfs to supergiants over 100 solar masses. A star's life cycle depends primarily on its initial mass.
A band on the Hertzsprung-Russell diagram representing stars fusing hydrogen into helium. Stars spend the majority of th...
A luminous giant star that has exhausted its core hydrogen. The outer layers expand and cool, giving a reddish appearanc...
The collapsed core of a massive star after a supernova, with 1.4-2 solar masses in a sphere about 20 km across. Incredib...
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