earth and its neighbors

                   solar system:the sun and the objects that are traveling around it.

      planet:any of the eight large bodies that travel around the sun and shine by reflecting its light   

     gravity:a force of attraction,or pull between any objects and any other objects around it.

                  inertia:the tendency of a moving objects to keep moving in a straight line.

                                                  

                                                                                                             

lithosphere:the hard,outer layer of earth,about 100 kilometers thick.

crust:the rocky surface that makes up the top of lithosphere.

                         resource:any material that helps support life on earth

                                     hydrophere:earth water