Northern lights: How ‘black’ auroras actually work

15 abril 2015

While our understanding of how the aurora’s shimmering curtains of colour are formed, scientists have struggled to explain the black patches between the bright beams. Now scientists have discovered what happens at the heart of these so-called «black aurora». 
http://feeds.sciencedaily.com/~r/sciencedaily/~3/UujGbUK37m0/150415090904.htm