The Star Wars movies take place "a long time ago in a galaxy far, far away" and are not set in a specific year. The movies begin with this phrase, but do not provide any further detail about the time period in which they take place. However, some fans have attempted to place the events of the movies in Earth years. One theory ties the Star Wars chronology to Earths by using crossover characters in the video game SoulCalibur IV and concludes that A New Hope took place around 4.7 billion years ago, around the time the Earth or the Solar System was formed. Another theory attempts to determine when in our universe's history Star Wars could occur based on the presence of mature planets and intelligent life, and concludes that Star Wars needs to be at least 9 billion years after the big bang. However, it is important to note that these are just fan theories and are not officially recognized by the creators of Star Wars.