CLASS 6 · LEARNING KNOWLEDGE

Dwarf planets and small bodies in the Solar System – basics

How it works

Dwarf planets are celestial bodies that move around the Sun, have enough mass to be approximately round, but have not cleared other objects from their orbit. Well-known dwarf planets are Pluto, Eris, Haumea, Makemake and Ceres. Small bodies include asteroids, comets and meteoroids. Asteroids are usually rocky and are found mainly in the asteroid belt between Mars and Jupiter. Comets consist of ice and dust and can develop a tail when approaching the Sun. Meteoroids are smaller pieces of rock or metal that become visible as meteors (shooting stars) when entering Earth's atmosphere.

Note
Dwarf planets are not planets because they have not cleared their orbit. Small bodies are distinguished according to their structure and behavior: asteroids are usually rocky, comets are icy and can develop a tail near the Sun, meteoroids are small pieces of rock or metal.

An example

Which of the following celestial bodies is a dwarf planet?

Pluto is a dwarf planet because it orbits the Sun, is almost round, but has not cleared its orbit.

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50 Exercises

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Own explanation and own practice exercises by AmyMath. Subject reference framework: Astronomy. The topic assignment may vary by federal state.