A planet was a celestial body orbiting a star or stellar remnant that was massive enough to be rounded by its own gravity, was not massive enough to cause thermonuclear fusion, and had cleared its neighbouring region of planetesimals.

Planets of the Velara Galaxy were very differentiated, possessing various sizes, tilts of axis, orbits, rotation periods, environmental conditions and landscapes. Most of the inhabited worlds possessed an atmosphere made primarily from nitrogen and oxygen, but some of them, like Naeda, had unique atmospheres to which their native life forms had adapted.

Planets were widely viewed as "cities" on the pangalactic scale.