Photos: Northern lights glow over the Midwest

Science

1 The northern lights as seen from Grand Portage, Minn. on Monday, Sept. 26, 2011. The northern lights, also known as aurora borealis, are a luminous glow of the upper atmosphere which is caused by energetic particles that enter the atmosphere from above, according to the University of Alaska-Fairbanks. 
2 The northern lights as seen from Grand Portage, Minn. on Monday, Sept. 26, 2011. 
3 Cloud cover allows a slice of northern lights to shine over Devil Track Lake near Grand Marais, Minn. early on Wednesday, Sept. 28, 2011. 
4 Northern lights as seen near Grand Rapids, Minn. on Monday, Sept. 26, 2011. 
5 The northern lights as seen over Lake Michigan, near Manistee, Mich. on Monday, Sept. 26, 2011. 
6 Northern lights seen from Kennebec, S.D. on Monday, Sept. 26, 2011. 
7 Northern lights seen from Kennebec, S.D. on Monday, Sept. 26, 2011.