Edwin hubble is credited for the initial development of the big bang theory, an idea which to explain the formation of the universe over 15 billion years ago. which piece of evidence did hubble find that led him to begin the development of the big bang theory?

In 1923 when Hubble spotted a Cepheid variable star in what was called Andromoda Nebula and he was able to show that Andromoda was a million light years away ,which meant that it obviously wasn’t just a cloud of gas but a whole galaxy itself.And his discovery led to him becoming the most famous astronomer in the world just overnight ,because he brought us the fact that the “world” was bigger than we thought it was