Editing Encyclopedia:Manual of Style (section)

===Celestial bodies===
{{Main|Wikipedia:Manual of Style/Capital letters#Celestial bodies}}
{{See also|Wikipedia:Naming conventions (astronomical objects)}}
The words ''sun'', ''earth'', ''moon'', and ''solar system'' do not take capitals in general use ({{xt|The sun was over the mountain top}}; {{xt|The tribal people thought of the whole earth as their home}}). They are capitalized when the entity is personified ({{xt|Sol Invictus ('Unconquered Sun') was the Roman sun god}}) or when used as the name of a specific body in a scientific or astronomical context ({{xt|The Moon orbits the Earth}}; but {{xt|Io is a moon of Jupiter}}).

Names of planets, moons, asteroids, comets, stars, constellations, and galaxies are proper names, and therefore capitalized ({{xt|The planet Mars is in the constellation Gemini, near the star Pollux}}). The first letter of every word in such a name is capitalized ({{xt|Alpha Centauri}} and not {{!xt|Alpha centauri}}; {{xt|Milky Way}}, not {{!xt|Milky way}}). Words such as ''comet'' and ''galaxy'' should be capitalized when they form part of a proper name, but not when they are used as a generic term ({{xt|Halley's Comet is the most famous of the comets}}; {{xt|The Andromeda Galaxy is a spiral galaxy}}).