Universe

• Universe 


  everything! All matter, energy and space
• Galaxy 


  collection of stars, held in a group by gravity
• Star 


  Ball of gas, gives out light and heat by nuclear reactions
• Solar system 


  A collection of planets, asteroids and moons orbiting a star
• Planet 


  Large, round objects, orbits a star
• Moon 


  Natural objects, orbits planet
• Asteroid 


  rock orbiting a star
• Comet 


  lump if ice and dust