Rotate means to spin.  A top spins.  They rotate.  A planets rotate.  A planets moves like a top.

Spin means to turn around like a top spins.  A carousel spins.  A planet spins.  This is also called to rotate.

A planet goes around the Sun.  A moon goes around a planet.  This is called to orbit.  Orbit means to go around something.

Something that goes around something is called a satellite.  A moon orbiting a planet is a satellite.  There are man made satellites that orbit the Earth.  These satellite get information and photos of the Earth from space.  They also help with communication of phones, television and internet.

Planets are very big.  Planets are in space.  Planets can be made of rock or gases.  Earth is a planet.  There are 8 planets in our Solar System.

A moon is made of rock.  A moon os very big.  A moon is smaller than a planet.  A moon goes around a planet.

The Sun is a star.  The sun is very, very, big.  The Sun is in space.  The Sun is very, very hot.  The Sun is made of burning gas!

Our solar system is in space.  Our solar system has a Sun, 8 planets and their moons.  The planets go around the Sun.