Astronomical objects are significant naturally occurring physical entities, associations or structures which current science has demonstrated to exist in outer space. The term astronomical object is sometimes used interchangeably with astronomical body. Typically an astronomical body refers to a single, cohesive structure that is bound together by gravity (and sometimes by electromagnetism). Examples include the asteroids, moons, planets and stars. Astronomical objects are gravitationally bound structures that are associated with a position in space, but may consist of multiple independent astronomical bodies or objects. These objects range from single planets to star clusters, nebulae or entire galaxies. A comet may be described as a body, in reference to the frozen nucleus of ice and dust, or as an object, when describing the nucleus with its diffuse coma and tail. The terms astronomical objects and astronomical bodies differ from celestial objects and celestial bodies only in that the latter terms do not include the Earth.[1]
The table below lists the general categories of objects by their location or structure.
| Solar System | Extrasolar objects | ||
|---|---|---|---|
| Simple objects | Compound objects | Extended objects | |
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