The sunset was crimson red, more vibrant than any sunset she had seen before. Later she learned that was because of the huge number of particulates in the air caused by the detonations.

Earth had been attacked, not by humans, but by some alien intelligence. Kinetic projectiles had rammed into the upper atmosphere at relativistic speed, bringing down scorching plasma over the equator.

The Earth was burning, slowly, but burning still. It would no longer support human life, or anything more delicate than soap scum in two weeks time.

Earth’s colonies faired no better, the attacks shattered the colonies on mars, the colonies on the moon, every habitable satellite. Anything with a orbit that could be predicted was vaporized. Only humanities small fleet remained.

That’s why they left, to get out before whatever, whoever, wanted humanity destroyed came to finish the job. Most of the ships were designed for long flights, few moving parts. If they were lucky, humanity would make it to Alpha Centauri in 43 years.