The US Geological Survey issued a red alert Tuesday, which means a major eruption is imminent or underway and ash could affect air traffic
Michelle Coombs of the USGS described it as " very hazardous for aviation," and said her team isn't quite sure what caused Tuesday's slightly more intense ash emissions.
US Geological Survey officials have said a phreatic eruption could happen at a crater at the top of the Kilauea volcano. It could send ash plumes as far as 12 miles from the summit crater, the Hawaiian Volcano Observatory said.
