Supernova LuminosityThe universe has many components that make it what it is over the years. The universe is made up of galaxies containing billions of stars, planets ranging from Mercury to Pluto, the Moon and many other objects. The universe is complex and no one knows where it begins or ends. Stars in the universe, including the Sun, vary in size and brightness depending on the distance seen and their real or apparent visual magnitude. Stars are huge, luminous celestial bodies and their components are tightly bound by gravity. Stars are often grouped into constellations; these were the stars that were easily visible to early astronomers and were not blocked by different celestial bodies. Supernovas are stars that explode violently, changing shape and brightness in the night sky, leaving their scar on the universe forever. There are a number of stars in the universe which are infinite in number and no one can configure them. exact amount. The stars of the universe vary from each other depending on their existence in constellations such as Orion, Plow, Deep South and Leo, among others. Stars also vary in size, with the largest stars being Eta Carinae and dwarfs, and the smallest like the Sun (Seeds, 14). Others vary depending on the system in which they rotate: temperature, their magnetic field, their chemical composition and their radius are just a few. The brightness of stars is determined by the luminosity which refers to the light they contain. To determine the luminosity of a star, the factors of its surface temperature t and radius length r must be calculated (Clark, 98). The universe contains ...... middle of paper ...... Stephenson, F. Historical supernovae, Supernovae: a survey of current research; Proceedings of the Institute for Advanced Study. Cambridge University Press, England, 198. Print.Croswell, K. The alchemy of the heavens: searching for meaning in the Milky Way. United States, Anchor Books, 1996. Print.Johnson, George. Miss Leavitt's Stars: The Untold Story of the Woman Who Discovered How to Measure the Universe. New York: WW Norton, 2005. 50. Print. New views of the solar system. Chicago: Encyclopedia Britannica, 2009. 7, 97. Print.Schawinski, K. et al. Supernova Shock Breakout from a Red Supergiant 2008. 2 Print.Seeds, Michael A. and Dana Backman. Universe: solar system, stars and galaxies. 7th ed. Boston, MA: Brooks/Cole, Cengage Learning, 2012. 13, 14, 337. Print. Woodruff, John. Firefly Astronomy Dictionary. Toronto: Firefly Books, 2003. 209. Print.