Space is a vast empty void. The only truth in that sentence is that space is vast. And like the humans of Earth, space has no concern for chaos, or unintended consequences. Space simply is, and was, and will be.
Three super-powers on Earth spar for superiority and resources while faint concern for not destroying the planet. Distrust is rampant, and it is difficult for the leaders in charge to know whom to trust.
Three super-powers on Earth spar for superiority and resources while fainting concern for peace and the planet. South America is no longer off the table for a cash and raw materials strapped United States. When the American military enters Central America, Russia seizes its chance to retake the Ukraine. China must put down a rebellion before it falls from within.
A washed-up, old-school astronomer discovers the planet is doomed by events set in motion billions of years before the Earth was even formed when he discovers Omega is barreling down on the Earth. Even this is not enough to convince the super-powers to work together....