The Planet X Disaster. Quick read, #3

Long before Earth is a planet, across the galaxy, a giant rouge planet is ejected from its solar system by an exploding supernova. For billions of years it continued its trek across the galaxy to eventually pose a threat to the newly evolved and present Earth. While discovered by a humble astronomer and recognized the danger it is, all hope of saving Earth is abandoned, and Divine intervention is called upon.
The mythical and elusive Planet X is discovered, but not recognized as the miraculous savior of all humankind.