A

David

Darling

greatest elongation

This diagram shows various possible elongations, each of which is the angular distance between a planet and the Sun from Earth's perspective.

This diagram shows various possible elongations, each of which is the angular distance between a planet and the Sun from Earth's perspective.


The greatest elongation is the maximum angular separation of an inferior planet (one whose orbit lies within that of Earth, i.e. Venus or Mercury) from the Sun at a given apparition.