Revealing 
                  Stellar Evolution
              
             
            
           
           
            
             This 
                  is a Hubble image of a
             
              planetary nebula
             
             , a dying star 
                  that blasts its outer layers of gas into space. Astronomers 
                  study the colors and patterns in such pictures to learn the 
                  secrets of planetary nebulas, including their temperature, the 
                  speed of their exploding gases, and their chemical components. 
                  By piecing together these details, scientists can record the 
                  evolution of dying stars
            
            .
            
             This 
                  is a Hubble image of a
             
              planetary nebula
             
             , a dying star 
                  that blasts its outer layers of gas into space. Astronomers 
                  study the colors and patterns in such pictures to learn the 
                  secrets of planetary nebulas, including their temperature, the 
                  speed of their exploding gases, and their chemical components. 
                  By piecing together these details, scientists can record the 
                  evolution of dying stars
            
            .