The Northern Lights glow green in a spectacular light show above a field of trees frozen solid with snow. (Photo by Jaak Sarv/Solent News & Photo Agency)

Death Muammar Muhammad Abu Minyar al-Gaddafi (7 June 1942 – 20 October 2011) in Misrata on October 20, 2011. The veteran strongman was killed on as new regime forces crushed the last pocket of resistance in his hometown Sirte, the National Transitional Council said. (Photo credit should read MAHMUD TURKIA)

Presenters Jennifer Lopez and Cameron Diaz speak onstage during the 84th Annual Academy Awards held at the Hollywood & Highland Center on February 26, 2012 in Hollywood, California. (Photo by Kevin Winter/Getty Images)

Audrey Hepburn cooking at home, 1954. Colorized by Dana Keller.

“Touring the Koko-en Gardens adjacent to the Himeji castle was an unexpected highlight of our visit”, wrote Jeff Solar, 64, of Silver Spring, Md., about his trip to Japan. “The fall colors were outstanding and the gardens were both amazing and a bargain (just a few Yen added to the cost of the Himeji Castle admission)”. (Photo by Jeff Solar/2017 Washington Post Travel Photo Contest)

A truck carrying iron ore moves along a road at the Fortescue Metals Group (FMG) Christmas Creek iron ore mine located south of Port Hedland in the Pilbara region of Western Australia, November 17, 2015. (Photo by Jim Regan/Reuters)

Fresh produce and baskets of fish surround a woman at the Siti Khadijah market in Kota Bharu, Malaysia. (Photo by Duratul Ain D.)

These are the dunes of the Namib Desert, taken by Korea's Kompstat-2 satellite. The blue and white area is the dried riverbed of the Tsauchab river. (Photo by The European Space Agency)