photon sphere

Fetched 2026-10-26 (cache).

Synonyms: photosphere

Antonyms: photosphere

Related words from Datamuse; suggestions, not definitions.

Noun

1. {{lb|en|cosmology}} Of a black hole, a spherical limit around a [[black hole]] at such distance that any photon meeting it tangentially is constrained to travel in a circular [[orbit]]; {{lb|en|more loosely}} the region between this limit and the [[event horizon]].

Source: Wiktionary · CC BY-SA 4.0 (Wiktionary dump) · cached copy, not a rewrite.