A small Solar System body (SSSB) is an object in the Solar System that is neither a planet nor a dwarf planet, nor a satellite of a planet or dwarf planet:
This encompasses all comets and all minor planets other than those classified as dwarf planets, i.e.:
The term was first defined in 2006 by the International Astronomical Union.
It is not presently clear whether a lower size bound will be established as part of the definition of small Solar Sy...
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A small Solar System body (SSSB) is an object in the Solar System that is neither a planet nor a dwarf planet, nor a satellite of a planet or dwarf planet:
This encompasses all comets and all minor planets other than those classified as dwarf planets, i.e.:
The term was first defined in 2006 by the International Astronomical Union.
It is not presently clear whether a lower size bound will be established as part of the definition of small Solar System bodies in the future, or if it will encompass all material down to the level of meteoroids, the smallest macroscopic bodies in orbit around the Sun. (On a microscopic level there are even smaller objects such as interplanetary dust, particles of solar wind and free particles of hydrogen.)
Except for the largest, which are in hydrostatic equilibrium, moons differ from small Solar System bodies not in size, but in their orbits. Moons' orbits are not centered around the Sun but around other Solar System objects such as planets, dwarf planets...
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