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  3. Binary Star
Stellar Astronomy

Binary Star

Definition

A star system consisting of two stars orbiting around their common center of mass. Binary stars are very common, with more than half of all star systems being binaries or multiples. They are important for determining stellar masses.

Related Terms

Star

A massive, luminous sphere of hot gas held together by gravity, generating energy through nuclear fusion. Stars range fr...

White Dwarf

A stellar core remnant of electron-degenerate matter, Earth-sized but with a mass comparable to the Sun. The final state...

Neutron Star

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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Full Glossary

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