Matching Pairs Galaxy Universe Review Online version Galaxy, Universe, Components of Universe Review by Andrea Soliz 1 Nebula 2 Spiral Galaxy 3 Irregular Galaxy 4 Galaxy 5 light year 6 Big Bang Theory 7 red shift 8 blue shift 9 Elliptical Galaxy 10 star a hot ball of gas that burn elements like hydrogen and helium through the process of nuclear fusion. The theory that our universe, which was once a small, dense ball of energy, exploded and expanded to create the universe we know today. the concept that an object is moving closer and closer. the distance a single beam of light travels in one year. The unit of measurement used to measure the distance of objects in outer space. A system of billions of stars with dust and gas. cloud of gas and dust in space that forms stars or is formed by the death of a star. the concept that an object is moving further away