The Earth is where we live.  The Earth is very, very big.  The Earth is made of rock.  The Earth is in space.

Space is very big!  Stars, planets, and moons are in space.  The Sun is in space.  

The Sun is a star.  The Sun is very hot.  The Sun is made of burning gas!

Stars are very, very big,  Stars looks small because they are so far away.  Stars are made of gas.  Stars are very hot.  All suns are stars!

A planet is very big.  Planets are in space.  The Earth is a planet.  Planets can be made of rock or gas.

A moon is big.  A moon is smaller than a planet.  A moon is made of rock.  A moon goes around a planet.  The Earth has one moon!  We can see the moon in the night sky!