A partially frozen Niagara Falls is seen on the American side lit by lights during sub freezing temperatures in Niagara Falls, Ontario March 3, 2014. (Photo by Mark Blinch/Reuters)

Actresses Vonnie Lui (R) and Yukiku Suou (L) attend the “3D s*x And Zen: Extreme Ecstacy” photocall at the Majestic Beach Pier during the 64th Cannes Film Festival on May 14, 2011 in Cannes, France. (Photo by Michael Buckner/Getty Images)

Kazuo Hirai, President and Group CEO of Sony Computer Entertainment America, presents the Playstation Vita at the Sony Playstation media briefing on the eve of the Electronic Entertainment Expo (E3) on June 6, 2011 in Los Angeles, California. More than 45,000 people are expected to attend the annual three-day convention to see the latest games and announcements from the gaming industry. (Photo by David McNew/Getty Images)

Atmosphere during the auction of antique and modern furniture and other collectibles from Michael Jackson's last residence, his Holmby Hills mansion, held at Julien's Auctions Gallery on December 12, 2011 in Beverly Hills, California (Photo by Mark Davis/Getty Images)

Lenticular cloud and zebra. (Photo by National Geographic)

Photographer Ma Hongjie has spent 11 years documenting families in various parts of China for his upcoming book The Family Belongings of Chinese People. Here: a couple with their belongings and vegetables in Hebei Huailai county. (Photo by Ma Hongjie)

The Mike O'Callaghan–Pat Tillman Memorial Bridge is an arch bridge in the United States that spans the Colorado River between the states of Arizona and Nevada. The bridge is located within the Lake Mead National Recreation Area approximately 30 miles (48 km) southeast of Las Vegas, Nevada, and carries U.S. Route 93 over the Colorado River.