The end of the Mayan calender.

December 12, 2012 a missile was detonated.
It was the end of the Mayan calender and the end times prophecy were not coming true but the realization why the Mayans ha picked this date became apparent. A comet was approaching. It was big and would pass between the earth and the sun. It would cause an eclipse that would be brighter than anything ever seen. A near planet sized comet that would be brighter than the sun and causing a halo that would surely blind everything looking at it. A decision was made to attempt an alteration of the path of the comet to see if it could be done in the event a comet would be close to impacting the earth at some time in the future.
December 12, 2012 a missile was detonated diverting the path of the comet by .00163 degrees.

Two thousand years later...
Ochet looked up and cursed the sky in anger. He had neither cursed nor really felt this much anger in his 1200 Celion years. His world was in ruins and it was due to one thing. The comet. For nearly six hundred thousand years the comet had passed their planet and it was the instigator for their science based peaceful existence. All eyes turned to the comet looking for explanation of what it was. It took thousands of years of work to get a close look at it and to understand astronomy and physics. Now their world was falling apart. No comet. The explanations turned to speculation and now different beliefs were dissolving into conflict. A rise of superstition and fanaticism. Violence. Ochet wept for his race. Silently mourning.