Booming Mystery

What's behind mysterious booms?

Phenomena produce theories, but no answers By Alex Roth UNION-TRIBUNE STAFF WRITER April 23, 2006 Life can serve up a good mystery every once in a while. Weird things happen that defy explanation, that make us wonder how much we really know about the world. Something of the sort happened in San Diego County shortly before 9 a.m. Tuesday, April 4, and so far no one has come forward with an explanation. “My garage door is double steel and it weighs about 500 lbs. It was rattling back and forth like a leaf in the wind for about 3 or 4 seconds.” – e-mail from University City resident on April 4 disturbance Whatever it was, it caused a woman's bed to shake in Lakeside. It created waves in a backyard pool in Carmel Valley. It set off car alarms in Kearny Mesa and rattled windows from Mission Beach to Poway to Vista. At various spots throughout the county, people reported a rumbling sound or a booming noise. Scientists insist it wasn't an earthquake. The Federal Aviation Administration has no record of any planes producing a sonic boom by breaking the sound barrier. Camp Pendleton officials say no activities on the Marine base could have created such a disturbance. There were no large explosions in San Diego County that day, and no meteor fireballs were reported in the sky that morning. What was it, then?