At 5 p.m. on may 30 i was driving on a tree lined town street (four lanes) with no apparent obstacles when i was certain i'd been hit by gunfire, except it sounded more like a canon. nothing was immediately apparent except the rush of wind yet i could see that the passenger side windows were closed (as were all windows). i pulled over and looked at the car noticing that my sunroof was shattered! i called 911 as it was clear that nothing natural had hit my car; no projectiles were found and the responding policeman said there was no debris in the road behind me. the glass pointed outward indicating that the explosion originated from within the vehicle. this was a very frightening experience and it was not until i got home and researched the subject that i read that these spontaneous explosions of tempered glass are not uncommon.