In astronomy, the terms object and body are often used interchangeably. However, an astronomical body or celestial body is a single, tightly bound, contiguous entity, while an astronomical or celestial object is a complex, less cohesively bound structure, which may consist of multiple bodies or even other objects with substructures.
Examples of astronomical objects include planetary systems, star clusters, nebulae, and galaxies, while asteroids, moons, planets, and stars are astronomical bodies. A comet may be identified as both body and object: It is a body when referring to the frozen nucleus of ice and dust, and an object when describing the entire comet with its diffusecoma and tail.
I've never seen this distinction made anywhere else, so I'm not sure if it's at all rigorous? If not, is it simply outdated/historical or is the information just plain false?
Thanks.
(Also, apologies if this is the wrong place to post this -- please let me know if it is.)
