Mary Gallagher, photographed at her home in October 2007, the year after her husband, Marine Gunnery Sgt. James Gallagher, took his own life. Tina Fineberg/AP hide caption

itoggle caption Tina Fineberg/AP

Oil burns at the Ixtoc 1 offshore drilling rig in December 1979. The rig dumped 140 million gallons of crude oil into the Gulf of Mexico and covered about 170 miles of the South Texas coast, including Galveston. John Hoagland/Liaison/Getty Images hide caption

itoggle caption John Hoagland/Liaison/Getty Images

Sarah Reeves, 19, dances the schottische with Ryder Cude, 15. Vikiann Gunter for NPR hide caption

itoggle caption Vikiann Gunter for NPR

Carl Main of Caddo Gap, Ark., removes flood debris from a pile near Langley, Ark., Sunday. Search and recovery efforts continue after flooding swept through a nearby campground early Friday, killing at least 19 people. Authorities believe just one, 8-year-old Jadyn Basinger, remains missing. Sue Ogrocki/AP hide caption

itoggle caption Sue Ogrocki/AP

A cluster of Bill Halter and Blanche Lincoln campaign signs at an intersection in Little Rock, Ark., on Tuesday. Danny Johnston/AP hide caption

itoggle caption Danny Johnston/AP

A view of the wreckage at the BP facility in Texas City, south of Houston, a day after the explosion on March 23, 2005. William Philpott/AFP/Getty Images hide caption

itoggle caption William Philpott/AFP/Getty Images