Our solar system is composed of nine planets that orbit one star, the Sun.  The Sun is the center of our solar system and provides the light and warmth we see and feel every day.  Each planet in our solar system is a different distance from the Sun and has its own unique features.  To our knowledge, life exists on only one planet in our solar system - EARTH. What do you think makes Earth unique so that life only exists here?       Some planets in our solar system are closer to the Sun than others.  This is because they have different orbits.  An orbit is a path a planet travels around the Sun that looks like a circle or ellipse.  Some orbits are small like the orbit of Mercury and others are large like the orbit of Pluto.  If the orbit of the Earth were the size of a dime, the orbit of Pluto would be the size of a bicycle tire!
 
To better understand our solar system, it is important to know where the planets are located and what orbits they have.     What effect do you think the distance from the Sun has on the planets like Mercury or Pluto? Click here to continue!