Star Cults existed in an alternate timeline where Earth and its moon were the only planetary bodies in the entire universe. (TV: The Big Bang)
According to a brief conversation between Amelia Pond's aunt Sharon and a psychiatrist, Christine, people seeing or believing in stars was common throughout history.
Sharon expressed worries that Amy would grow up and join a Star Cult and said that she didn't "trust that Richard Dawkins". (TV: The Big Bang)