What are the types of space objects ?
The International Astronomical Union (IAU) classifies objects in the Solar system into 3 categories :
1. Planet : a celestial body orbiting the Sun, with enough mass to assume a (nearly round) hydrostatic equilibrium shape, and that has "cleared the neighbourhood" around its orbit,
2. Dwarf planet : a celestial body orbiting the Sun, with enough mass to assume a (nearly round) hydrostatic equilibrium shape, but that has not "cleared the neighbourhood" around its orbit and is not a satellite,
3. Small Solar System Bodies : all other objects orbiting the sun that are not satellites.

Small Solar System Bodies of the Solar system include :
- Moons : celestial bodies that orbit a planet or a dwarf planet,
- Asteroids : rocky non-spherical left-over objects from the early formation of the Solar system. They travel around the sun and most of them are located within the main asteroid belt between Mars and Jupiter,
- Comets : icy bodies that can also contain minerals, rocks and dust left over from the formation of the solar system. They travel around the sun and can be found mostly beyond Neptune in the Kuiper Belt, as well as far beyond Pluto in the Oort cloud,
- Meteoroids : objects in space that often come from other larger bodies such as comets, asteroids or even moons and planets. Meteoroids can be rocky, others can be metallic, or combinations of both. Their sizes range from dust grains to small asteroids.