Jan 9, 2014, physicsworld.com: Burning soil fuels ball lightning Citat: "...It started out a bright purple-white colour before gradually turning orange, white and finally red. The researchers say this supports the idea that the energy source for ball lightning is a burning core of soil...Analysing the pictures taken, the researchers found clear emission lines from silicon, iron and calcium – the main components of soil...He believes that the atypically large size of the ball and the mysterious 100 Hz intensity fluctuation prevent the event being labelled ball lightning with certainty, although he believes it is "very likely"..."
