Children walk down one of the many empty streets next to the vacant lots where houses once stood. David Gilkey/NPR hide caption

itoggle caption David Gilkey/NPR

Researcher John Clements in the early 1980s, after he figured out that lungs need surfactants to breathe. David Powers/Courtesy of UCSF hide caption

itoggle caption David Powers/Courtesy of UCSF

Newly elected mayor Martin O'Malley (left) waves to supporters in Baltimore in November 1999. Gail Burton/AP hide caption

itoggle caption Gail Burton/AP

Angelica Rivera, the wife of Mexico's President Enrique Pena Nieto, has been embroiled in controversy over the purchase of a luxury home. Thomas Samson/AP hide caption

itoggle caption Thomas Samson/AP

HitchBOT, a hitchhiking robot, sits with German tourists Sarah Strempel and Eric Vogel in the back seat of a vehicle as they and their companions prepare to leave Marblehead, Mass., after picking up hitchBot for its first ride on July 17. Stephan Savoia/AP hide caption

itoggle caption Stephan Savoia/AP

U.S. Marines arrive at Saudi Arabia's Dhahran Air Base on Aug. 21, 1990. The U.S. began a buildup in the region just days after Iraq invaded Kuwait on Aug. 2 of that year. The U.S. military has been active in Iraq virtually nonstop for the past quarter-century. Gerard Fouet/AFP/Getty Images hide caption

itoggle caption Gerard Fouet/AFP/Getty Images

Flames from the Rocky Fire approach a house in Lower Lake, Calif., Friday. More than 5,000 firefighters are now battling large blazes in California; hundreds of residents are under evacuation orders in affected areas. Justin Sullivan/Getty Images hide caption

itoggle caption Justin Sullivan/Getty Images

Traditional recipes for duck confit, or confit de canard, can require dozens of steps to prepare. David Lebovitz's fake take cuts the steps down to five. Ed Anderson/Courtesy of Ten Speed Press hide caption

itoggle caption Ed Anderson/Courtesy of Ten Speed Press

Jericho the lion, right, seen here fighting with Cecil last year, was the subject of competing stories Saturday, as groups in Zimbabwe disagreed over whether he had been killed. KEN WATKINS/SN /Landov hide caption

itoggle caption KEN WATKINS/SN /Landov

Refugees line up to apply for asylum at a reception center in Berlin, Germany. Figures released last week showed that about 180,000 asylum applications were filed in the first six months of 2015, more than twice as many as in the same period last year. Markus Schreiber/AP hide caption

itoggle caption Markus Schreiber/AP

Palestinian Prime Minister Rami Hamdallah inspects a home that was badly damaged from a suspected attack by Jewish extremists in the West Bank village of Douma. An 18-month-old child was killed and other family members seriously injured. Prime Minister's Office/APA/Landov hide caption

itoggle caption Prime Minister's Office/APA/Landov

Organic farmer Margot McMillen holds a grape leaf damaged by pesticide drift on her farm, Terra Bella Farm, in central Missouri. Kristofor Husted/Harvest Public Media hide caption

itoggle caption Kristofor Husted/Harvest Public Media