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  3. Neutron Star
Stellar Astronomy

Neutron Star

Definition

The collapsed core of a massive star after a supernova, with 1.4-2 solar masses in a sphere about 20 km across. Incredibly dense; a teaspoon would weigh about a billion tons. Some emit radiation beams and are called pulsars.

Related Terms

Pulsar

A highly magnetized rotating neutron star emitting beams of radiation from its magnetic poles. As it rotates, the beams ...

Supernova

A powerful explosion at the end of a massive star's life, briefly outshining an entire galaxy. Supernovae scatter heavy ...

Black Hole

A region of spacetime where gravity is so strong that nothing, not even light, can escape once past the event horizon. B...

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Full Glossary

Browse all 66+ space and astronomy terms.

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