Concept
Singularity
A point of infinite density inside a black hole.
The theoretical region at a black hole's centre where current physics breaks down. Resolving it requires a quantum theory of gravity.
Overview
The theoretical region at a black hole's centre where current physics breaks down. Resolving it requires a quantum theory of gravity.
See also
Event Horizon
The point of no return around a black hole.
Photon Sphere
Where light itself can orbit a black hole.
Perihelion
The closest point in an orbit to the Sun.
Aphelion
The farthest point in an orbit from the Sun.
Perigee
The closest point in an Earth-centred orbit.
Apogee
The farthest point in an Earth-centred orbit.