In 536 AD something weird happened in the sky. A mysterious, dusty fog appeared, blocking the Sun, causing temperatures to plunge and setting off years of around-the-world chaos - drought, crop failures, summertime snow in China, widespread famine and more. ... "It came about during this year that a most dread portent took place. The sun gave forth its light without brightness, like the moon, during this whole year, and it seemed exceedingly like the sun in eclipse, for the beams it shed were not clear nor such as it is accustomed to shed."