STARS!!!!!

                   Whats up!!! This is Evan and today I am going to tell you about..... STARS!!!! Our sun is a star and it is huge but there are tuns of stars that are a lot bigger than the sun. 


         this is were I got this picture
           
                The first thing I will talk about is how stars shine. All stars are like glowing plasma just big balls of it. The stars are held together by there own gravity. They shine because of what the gases do inside of the stars. The gases do what is called nuclear fusion. This happens when two atoms in the gas come together and forms another atom. This makes light come out from the energy. 
 this is were I got that information from.


    

  this is where I got this picture

             


             Have you ever wondered how a star is classified as a star? Well that's what I;m going to tell you now. They are classified by what they contain. They have to contain certain elements. They contain mainly hydrogen and helium. 


        
               this is where I got this picture

 
               The next thing that I will talk about is how the sun changes over periods of time. The sun changes by the temperature changing. On a chart there would be a ton of squigly lines because the temperature accasionally goes down then up then down then up and it goes like that for a long time. 


             this is where i got this picture

          Now I will talk about how the weight of the sun effects the color of the sun. The biggest stars are red giants so red stars are the biggest stars. Our sun is a middle sized and it is a yellow star. The smallest star is a green star. 


                 this is where I got this picture.