Controlled burns are conducted in the Gulf of Mexico in an effort to burn off some of the oil in the water, 19 May 2010. John Kepsimelis / U.S. Coast Guard via Reuters

Controlled burns are conducted in the Gulf of Mexico in an effort to burn off some of the oil in the water, 19 May 2010. John Kepsimelis / U.S. Coast Guard via Reuters

Gulf oil spill photo gallery