Kirk sighed. "Romulus, the star in that system went supernova. Took out the whole system. The Federation couldn't or wouldn't help-- I don't know the details of why on that," because the other Spock hadn't explained about Shinzon's coup d'état or the Borg War, which was probably for the best, "but the Vulcans could. The black hole device was theirs and they used it to contain the supernova to stop it from taking out the rest of the sector. Nero was caught in the wake, as was the Vulcan ship that launched the red matter device into the supernova to contain it. They were both pulled back in time. Nero emerged on the day of my birth and the Vulcan ship some twenty-five years later, shortly before Nero took out Vulcan."