Somehow this post got lost a week or so ago. With the meteor that hit the Russian town, people got interested in sonic booms. Video and science pages on the Internet received lots of new traffic. Perhaps you looked it up too. Here’s a video from YouTube that does a pretty good job of explaining it – and showing it. We found one other explanation we liked too. It used a regular balloon in its explanation. Consider blowing up a balloon. As the ‘tip end expands’, imagine it’s a plane or meteor that’s pushing the tip end outward. As it continues to move forward (ideally at a higher rate of speed), it pushes the balloon out as far as it can. The balloon is expanding forward and outward — in the conical manner shown in the YouTube video. When the balloon can’t hold back the expanding air (or the imaginary plane as it continues to push forward at ever greater speeds), the inability to hold its shape is GONE – and you get the loud pop. That’s what the sonic boom is! Talk to your science, math, and physics teachers about it. See if they’ll let you do the in-class experiment with a whip – and hear the cracking of the whip no longer as something kind of “fun”, but “fun with an explanation” – you are breaking the sound barrier!! Enjoy!