On May 19, 1780, the skies over New England turned dark in the middle of the day. For more than two hundred years, New England's Dark Day had been shrouded in mystery. Some blamed volcanoes. Some suggested supernatural events. Some claimed it was a sign from the heavens. No one knew for certain what happened. Many thought the mystery would never be solved. Researchers at the University of Missouri were fascinated by the case. They began examining trees in all surrounding areas. Fire damage in a Canadian forest finally revealed the truth. Scientists looked at burned tree rings and discovered that huge wildfires once raged in the mountains near Ontario. The savage flames created blankets of black smoke. The smoke traveled high into the atmosphere, darkening the New England skies hundreds of miles away.