Glory of the Galaxy

On October 25, Qi Yuan 2620, a fireball hit the southeast and made a big hole in the ground. After people waited for it to cool down, they looked forward and found that it was not a fireball at all, not a comet, but an iron ball. The iron ball is so heavy that there is almost no way to shake it. Until 50 years later, the iron ball suddenly emitted blue light, shot into the sky, and then continued to expand. Until it expands to the entire earth....