The Northern Lights, also known as the Aurora Borealis, lit up the sky over parts of the U.S. They are a phenomenon caused by plasma ejected from the sun during a solar storm, which interacts with Earth’s geomagnetic field. | NBC News

Aurora australis lights up Australian skies

A rare aurora borealis turning the sky above the Matterhorn mountain red could be seen on Tuesday, November 12, in Italy's Aosta Valley. Reuters was able to verify the location with the shape of the roof and the outline of the mountains that matched the file and satellite imagery of the area. The date was verified by local news and weather reports. The rare northern lights seen across Europe were caused by a G4 geomagnetic storm, local media reported. (Production: Monica Naime, Eva Weininger) |