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An extraordinarily loud boom shook parts of South Carolina on Thursday, with witnesses across the state reporting a noise like a deafening thunderclap, or a huge explosion.<\/p>\n
But what caused it? While residents and internet sleuths quickly came up with theories, experts just as quickly dismissed them, leaving a mystery that lingered a day later.<\/p>\n
About 5:30 p.m. on Thursday, the boom was heard throughout the central part of South Carolina, including the capital city, Columbia, and an area extending at least 40 or 50 miles east. The United States Geologic Survey said it was centered just about three and a half miles northeast of St. Andrews, in the Columbia metro area.<\/p>\n
There were no reports of damage or serious injury, but it left the region puzzled. Hundreds of residents described hearing the sudden, jarring noise, and a rumble that felt like an earthquake. <\/span>Many expressed their alarm on social media: \u201cIt felt like a bomb just went off,\u201d one person said, while another wrote, \u201cIt shook my room.\u201d<\/p>\n<\/div>\n<\/div>\n No company or entity immediately claimed responsibility. Many possibilities were ruled out. Some experts wouldn\u2019t commit to one theory yet.<\/p>\n So the question remained: What the heck was that?<\/p>\n The Richland County Sheriff\u2019s Department, which covers Columbia, did not seem to think so: \u201cR.C.S.D. has not been notified of any causes,\u201d it said. \u201cIf we receive any information that it was a law enforcement issue, we will provide updates.\u201d<\/p>\n No, according to NASA: \u201cWe have no eyewitness reports of a fireball and no satellite detections of a meteor over the area at the time,\u201d it said in an emailed statement.<\/p>\n So, we can categorically rule out a meteor? Not so fast: \u201cIt\u2019s still possible this was caused by a large meteor, and no one saw it,\u201d NASA added.<\/p>\n \u201cThis event is not an earthquake,\u201d said the U.S.G.S.<\/p>\n \u201cWe can confirm there was no earthquake activity this evening in or around Columbia, S.C.,\u201d the agency said on Thursday. \u201cThe last reported tremor in that area was a magnitude 1.9 on May 22. Nothing today.\u201d<\/p>\n<\/div>\n<\/div>\n The U.S.G.S., however, did offer a theory on what the sound might have been.<\/p>\n \u201cThe recorded waves and eyewitness reports are consistent with a sonic boom,\u201d the U.S.G.S. said in a statement.<\/p>\n A sonic boom is created when an object travels faster than the speed of sound, about 767 miles an hour.<\/p>\n The fast-moving object pushes air forward. When it reaches the speed of sound, these waves of air combine into shock waves, triggering a loud boom.<\/p>\n If the loud noise was indeed a sonic boom, that would open another mystery: What was the speedy object?<\/p>\n Not many things go that fast: The field is mostly limited to high-speed planes or spacecraft. And normally, because of the noise, planes are prohibited from hitting the speed of sound over land.<\/p>\n<\/div>\n<\/div>\n The agencies that operate such speedy vehicles had little to say.<\/p>\n NASA did not respond to a specific question about a possible boom-causing object. The Navy did not respond to a request for comment. The Air Force and Marines said on Friday they were looking into the matter but had no specific information.<\/p>\n As of Friday afternoon, the mystery lingers.<\/p>\n Livia Albeck-Ripka contributed reporting.<\/p>\n<\/div>\n<\/div>\nCould it have been a terror attack?<\/h2>\n
Did a meteor strike?<\/h2>\n
Seems like an earthquake then.<\/h2>\n
Tell me.<\/h2>\n