Celestial bodies are natural objects that we can observe in the sky.

We can divide celestial bodies in two main types: luminous bodies and non-luminous bodies.

Luminous celestial bodies can give off light and heat; and non-luminous celestial bodies can't give off light or heat.


Stars are luminous bodies. They are made of hot gas, so they can give off light and heat. The Sun is a star.


There are 4 different types of non-luminous bodies: planets, dwarf planets, moons and comets.

  • Planets: planets are large spherical bodies that orbit a star. To orbit means to move around a bigger object. Planets can be made of rocks (the Earth) or gas (Jupiter).

  • Dwarf planets: dwarf planets are like planets but much smaller. Pluto is a dwarf planet.

  • Moons: moons are celestial bodies that orbit a planet. The Earth's satellite is the Moon.

  • Comets: comets are celestial bodies made of ice, gas and dust that orbit a star.

Time for the videos.

On the first video, you could compare the size of different celestial bodies, from Earth's moon to the biggest stars in the universe.

On the second video, you could see different pictures from one of the most famous comets: halley comet.

Do you like games? Go to the games section to play some games about celestial bodies.