1. Galaxies of Stars

2.  By far the nearest star to earth.  A star is a large self-luminous body in space that creates its own radiant energy.  It gets its energy from nuclear fusion  During fusion under conditions of extreme heat and pressure in the star, the nuclei of two hydrogen atoms join to form a single helium nucleus.

3.  Nuclear fusion reaction produces a huge amount of energy  Fusion reaction in larger stars such as red giants produce heavier elements such as carbon, oxygen, and iron  The formation of the heaviest natural elements requires the conditions found only in massive stellar explosions.

4.  A nubula (from Latin: "cloud"; pl. nebulae or nebulas ) is an interstellar cloud of dust, hydrogen gas, helium gas and other ionized gases.  The Orion Nebula (also known as Messier 42, or M42 ) is a diffuse nebula situated south of Orion's Belt. It is one of the brightest nebulae, and is visible to the naked eye in the night sky. M42 is located at a distance of 1,344 ± 20 light years [3][6] and is the closest region of massive star formation to Earth. The M42 nebula is estimated to be 24 light years across. [3][6]

8.  Is a phenomenon observed in some massive stars causing the ejection of a large portion of the star's mass.

10. Betelgeuse Rigel