The Future Was Yesterday’s fusion reactor containment failed when she was three days out from Rattlesnake Station. Automatic failsafes triggered within microseconds, shutting off the reactant supply and bringing the nuclear reaction to a halt, but a few hundred grams of sun-hot plasma now had a clear path to the supercooled magnets surrounding the reactor.
Yesterday’s operating system opened a ventral port from the reactor into open space. Almost all of the plasma was successfully shunted through this port and away from the ship, but a small fraction followed the path through the containment breach, touching off a massive detonation when they contacted the magnets.
The violent sideways kick of the explosion was the first Yesterday’s crew knew of the unfolding disaster. Apparent gravity changed direction twice in less than a second, first from the steady 1g of deceleration to the side as the explosion accelerated the ship into a spin, then from sideways to outward as the ship’s new centripetal force tugged the crew out from the center of the ship toward her bow and stern.
Shockwaves from the explosion traveled out from engineering, vibrating every centimeter of Yesterday’s rigid frame. Plastic instrument covers shattered, ceramic cups cracked, gangways shook themselves loose, and an infrasonic thrum blurred the crew’s vision as they struggled to understand what was happening.
The sound of the explosion came last. It was a titanic crack as though some forgotten god of the void had seized Yesterday and cracked her spine in retaliation for waking their anonymous slumber.
But there were no vengeful gods in the Big Black, and Yesterday’s spine was not actually broken. The explosion had pushed her structural integrity to the limit, but not past it. Yesterday held herself together.
Her crew tended to their wounded and carefully began the precise pattern of maneuvering burns that would counter Yesterday’s spin as efficiently as possible. They were safe, for the moment.
Beyond the moment? There was no way they could restart the crippled reactor, and the Kuiper Belt was a bad part of the Solar System to lose your fusion drive, especially on an outbound trajectory. Without the deceleration burn, they would fly right past Rattlesnake Station. There were no other permanent bases between them and the Oort Cloud. If someone couldn’t catch up to them and bring along enough reaction mass to overcome their velocity, nothing could stop Yesterday from going Dutchman.
Those were long term considerations. In the short run, all that mattered was power.
Without power, life support would fail. First they would asphyxiate. Then the cold would freeze their lifeless corpses solid. Yesterday’s capacitors could keep her essential systems humming for hours. Maybe a day at the outside. A rescue mission wouldn’t take days or hours. It would take weeks or months. Yesterday’s crew needed time. They needed power.
They knew how to get it.
While Yesterday’s spin was tamed, her crew took exacting measurements of their position and velocity. They sent the data along with a discreet mayday call back towards the Inner System on heavily encrypted channels. The message would take seven hours to reach Cislunar, the cradle of humankind’s nascent interplanetary empire. Hopefully, a ray of concentrated sunshine would reach back out towards them across the millions of kilometers of empty space, arriving fourteen hours after they sent their message.
If they were very lucky and their telemetry data was very good, that little photonic lifeline would score a direct hit on their emergency solar array, bringing them the power they needed to stay alive until help arrived.
If they were very lucky.