Parts of the subway system were shut down in the city of Bursa when a major power outage hit cities and provinces across Turkey on Tuesday. Anadolu Agency / Getty Images hide caption

itoggle caption Anadolu Agency / Getty Images

Cushing, Okla., is a major oil storage site. Amid record oil production, some analysts worry the U.S. will run out of places to put it all. Daniel Acker/Bloomberg via Getty Images hide caption

itoggle caption Daniel Acker/Bloomberg via Getty Images

Smart phones contain a silicon chip inside the camera that might be used to detect rare, high energy particles from outer space. J. Yang/Courtesy of WIPAC hide caption

itoggle caption J. Yang/Courtesy of WIPAC

Workers at Los Alamos National Laboratory used organic cat litter to clean up nuclear waste. The litter triggered chemical reactions that later caused a drum to burst. Department of Energy/Flickr hide caption

itoggle caption Department of Energy/Flickr

A 2008 view of the leading edge of the Larsen B ice shelf, extending into the northwest part of the Weddell Sea. Huge, floating ice shelves that line the Antarctic coast help hold back sheets of ice that cover land. Mariano Caravaca /Reuters/Landov hide caption

itoggle caption Mariano Caravaca /Reuters/Landov

Interior Secretary Sally Jewell speaks in Anchorage, Alaska. The Obama administration is requiring companies that drill for oil and natural gas on federal lands to disclose chemicals used in hydraulic fracturing operations. Dan Joling/AP hide caption

itoggle caption Dan Joling/AP

Bayway Refinery in Linden, N.J., is one of two refineries that are involved in the settlement. It's no longer owned by Exxon, but they are on the hook for the cleanup. Joel Rose/NPR hide caption

itoggle caption Joel Rose/NPR

The abandoned Cherokee Clay and Brick Mine in Lee County, N.C., may become a landfill for coal ash. Dave DeWitt/WUNC hide caption

itoggle caption Dave DeWitt/WUNC

A platform owned by Mexico's state-run oil company Pemex is seen off the Bay of Campeche in the Gulf of Mexico. The country has recently opened up its energy sector to foreign investors. Victor Ruiz/Reuters/Landov hide caption

itoggle caption Victor Ruiz/Reuters/Landov