Glossary · term

Black hole

Astronomy

Domain
Astronomy

Definition

A region where gravity has closed spacetime around itself, bounded by an event horizon that nothing crosses outward. Stellar ones start above about three solar masses; supermassive ones of millions to billions sit in galactic centres.

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From the Glossary database in Notion, last edited 2026-08-17. This page is the row, rendered by the build; nothing on it is written by hand.