[ WP ] This is an alternate dimension . The timetraveler ( s ) changed one thing to make the world how it is today .

Captain Yenrir stared at the monitors, easily multi-tasking as he absorbed multiple monitors worth of data his science and engineering teams had prepared for him. The good news was, the engineers could probably effect makeshift repairs that would at least get them home. It would take a months to recreate full replicas of the systems they had lost, but life sciences could make nutrient suspensions that would keep them from starving, and engineering said there was plenty of power from the solar arrays to scrub the atmosphere indefinitely, so a few months of discomfort was the worst they faced in that area. It concerned him somewhat to think what they might find when they finally got home, but for the moment, that was overshadowed by his second concern: 
 
 What really worried him was the data on the second monitor. They were currently in orbit of what was supposed to be a lifeless planet. It had the basic elements necessary to make it suitable for terraforming, but until a few cycles ago, it had no life of its own. In fact, just 100 cycles ago, he and his crew had been celebrating that fact, because it made this whole risky trip worthwhile: a planet suitable for terraforming, yet devoid of life so there would be no ethical considerations in doing so. They pictured themselves being hailed as heroes when they brought back word of this to their over crowded home world. 
 
 Then there was the disastrous test of the chrono-engine a few cycles ago. Yenrir exhaled sharply as he wondered what pack of idiots had been assigned to double check the ground team's calculations on the thing. The principal had been brilliant ( or so he was assured -- - command staff did n't necessarily have to be scientists ). They used a small engine that could create a tiny wormhole, leading 1 micro-cycle into the past, then channel energy back into it. The amount of energy was initially quite small: nothing you could n't get from a common fusion reactor. But cycling it through a time loop, it accumulated rapidly beyond anything a city full of reactors could produce. The ship's entire energy utilization structure had to be custom designed to deal with so much power, in fact. With such abundant power, achieving near-light speed travel was almost absurdly simple. Neighboring star systems were now within reach. 
 
 The trouble, as it always had been, was relativity. Who would sign on for these missions knowing that in what seemed like only ten years to them, centuries may have passed back home? But those clever physicists had a solution for that too: If you could create a wormhole a micro-cycle back in time, and if energy availability was no object, why not extend it ten years into the past and widen it enough for a whole space vessel to travel through? 
 
 Yes, why not? It would only be a causality issue if you returned *before* you left, but if you calculated correctly, you could travel for ten years, then return home exactly ten years later, and resume your life normally. Brilliant! Or at least, it would have been, if it had worked out that way. But apparently everyone had missed that there might be a side effect to using the chrono-engine to both amplify your power levels *and* open a wormhole of such signficant size. Oh, the power had been amplified alright: *exponentially. * 
 
 If they had n't reacted quickly, the entire ship might have been blown apart. As it was, there was no way to stop the reaction once it started, and they had been forced to eject the stage containing the chrono-engine. The last they had seen of it, it had been falling wildly away into a wormhole into the past. No one could tell him how far in the past; The readings were simply too large for their instruments to make sense of, since long distance time travel had never been the intent. 
 
 While the engineering crew struggled through damage control, the sciences division had discovered the rest of the story: the planet which had previously been devoid of life was now thriving. His science team had gone to work analyzing everything they could about the newly found dominant species. They were ugly to behold ( two arms, two legs, no tail, brain centralized in a single head -- utterly repulsive ), but they were tremendously intelligent, and were apparently at a stage where they were rapidly expanding their understanding of the universe. Clearly, their presence now made the planet off limits to terraforming. 
 
 `` How?'' he had asked, demanding an explanation for their presence, and what his science team told him made a grim kind of sense, although he could n't like the creatures any better for understanding the logic behind their unexpected presence. 
 
 Their best guess was that the chrono-engine module had tumbled out of control until the fierce energies it was creating burned out the stabilizers on the wormhole generator, then it had dropped out of the wormhole in a monstrously explosive burst of energy. Since the mathematics of wormhole generation automatically compensated for planetary motion, it appeared in the upper atmosphere of the planet's distant past, and sprayed its violent cascade of energy over the surface of the world. Somehow, all that added energy had catalyzed the elements of life that were already present, setting in motion a chain of events that had evolved into the creatures now occupying the planet below. The linguistic team said they called themselves *humans*. 
 
 `` We did this,'' Yenrir muttered quietly to himself, `` Gods help us.'' He leaned back, shaking three of his four heads, while six hands dismissed the contents of the reports on his monitor arrays. What would be the ultimate outcome, he wondered, when these creatures started exploring space themselves? Would they be friends or foes? For some reason he could not fathom, he shuddered at the thought. 
 

