How did Greenland get its name? When the Vikings discovered the northern island, it was fertile land, lush and green. But when the medieval warming period ended around 1,300, it froze. Ice was also advancing in Europe--and noticeably so. People actually prayed in churches that the glaciers wouldn't advance to overtake their villages. That's just some of the facts revealed in a ten-minute DVD called, "Unstoppable Solar Cycles." Most of the video is available below, but it is also available for order here.