The Clockwork Rocket

In a universe governed by alien physics, where light possesses mass and its creation releases energy, Yalda's world faces an existential threat. On her home planet, plants photosynthesize by emitting light into the perpetually dark night sky, and time itself is relative in startling ways – a journey to a neighboring star might consume decades for the traveler, yet only weeks for those left behind. This unique existence is shattered when strange, ultra-fast meteors begin to bombard their planetary system, precursors to an impending galactic collision. An entire galaxy, traveling at unprecedented speed, is on a catastrophic trajectory with their own. Humanity's sole hope lies in a desperate gamble: a fleet dispatched directly towards the approaching catastrophe, designed to travel as fast as possible. Aboard these vessels, millennia will pass for the crews, allowing generations to be born and raised, tasked with finding a solution to avert the collision. Meanwhile, back home, only weeks will have elapsed, leaving Yalda and her people to await a future forged by descendants they will never know.