http://www.nbc30.com/technology/10773508/detail.html?dl=mainclick WASHINGTON -- Could we be near the end of the world as we know it? The directors of The Bulletin of the Atomic Scientists have moved the big hand of their symbolic clock two minutes nearer to midnight. It now sits at 11:55 p.m. "We stand at the brink of a second nuclear age," the group said in a statement on Wednesday. "Not since the first atomic bombs were dropped on Hiroshima and Nagasaki has the world faced such perilous choices." By moving the hand of the Clock closer to midnight, which BAS called the figurative end of civilization, the group said it is drawing attention to the increasing dangers from the spread of nuclear weapons in a world of violent conflict. The group said was concerned about: * North Korea's test of a nuclear weapon. * Iran's nuclear ambitions. * A renewed emphasis on the military utility of nuclear weapons. * The failure to adequately secure nuclear materials. * The continued presence of some 26,000 nuclear weapons in the United States and Russia. Created in 1947, the Doomsday Clock has been adjusted only 17 times prior to Wednesday, most recently in February 2002 after the Sept. 11, 2001 terrorist attacks. BAS has added concerns about global warming to its calculations, said scientist Stephen Hawking, a BAS sponsor. "The dangers posed by climate change are nearly as dire as those posed by nuclear weapons," Hawking said. "The effects may be less dramatic in the short term than the destruction that could be wrought by nuclear explosions,. "Over the next three to four decades, climate change could cause irremediable harm to the habitats upon which human societies depend for survival," he said. "Nuclear weapons still pose the most catastrophic and immediate threat to humanity," said Martin Rees, president of The Royal Society. "But climate change and emerging technologies in the life sciences also have the potential to end civilization as we know it."