A mysterious basketball-size chunk of ice fell from clear skies on Sunday, leaving a manhole-size crater in a Northern California home. Federal Aviation Administration officials are reviewing radar data to determine if the ice fell from a plane over the Fremont, California, house, which lies in the flight path of San Francisco International Airport. FAA spokesman Ian Gregor said the ice was white rather than blue and probably didn’t drop from a plane’s lavatory. Scientists believe the ice could be a megacryometeor, a phenomenon triggered by global warming that causes the lower atmosphere to expand and rise, forming hail conditions despite clear skies. There are 40 documented cases of megacryometeors in the last 13 years.
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