That big boom you heard around lunchtime Tuesday in Davis and Weber counties? It was a planned detonation at the Utah Test and Training Range.
The Air Force blew up a motor from a Trident I ballistic missile at 12:28 p.m., a Hill Air Force Base news release said.
The detonation was part of an ongoing effort to eliminate old rocket propellant and destroy motors, as directed under the START treaty with Russia to reduce the number of ballistic missiles.
The Air Force said it takes atmospheric readings to check wind speed, direction and other factors to see if the explosion will be too loud for communities along the Wasatch Front.