northern lights

The Big Sable Point Lighthouse, near Ludington, Mich., stands tall beneath a fading display of northern lights, Nov. 7, 2004. According to a NASA Web site, the lights are caused by collisions between fast-moving electrons and the oxygen and nitrogen in Earth's upper atmosphere.

Northern lights shimmer over Lake Michigan and Ludington (Mich.) State Park as cars travel along M-116, Nov. 7, 2004. The display peaked about 9 p.m. before the aurora borealis began to fade.

The aurora borealis, or northern lights, light up the western sky over downtown Saginaw, Mich., and the Saginaw River, Nov. 7, 2004.

Northern lights are shown in the sky outside of Racine, Wis., Nov. 7, 2004.

Northern lights are shown above a covered bridge at Wilkinson Pioneer Park in Rock Falls, Iowa, Nov. 7, 2004.

The glow of the northern lights are visible north of Appleton, Wis., Nov. 7, 2004.

Green hues of the aurora borealis fill the sky above a farm along Highway D near Lake Church, Wis., Nov. 7, 2004.

A barn is silhouetted by the northern lights, Nov. 7, 2004, near Monticello, Ill.

The aurora borealis lights up the night sky north of Dunkerton, Iowa, Nov. 7, 2004