This dramatic four-frame animation shows a fireball meteor and itsdeveloping persistent "smoke" train, recorded two weeks ago i skies nearSalvador, Brazil.Indeed similar sights are astonishingly familiar world-wide towitnesses of this November's fireball-ric Leonid meteor storm.A few skygazers even discoveredthat some bright Leonid fireballs made faint, gentle,hissing sounds(!), a surprising effect only recentlyappreciated and understood.Accounts of fireballmeteors making noise have long bee viewedwith skepticism, particularly because sounds werereportedly heard just as the meteor was seen overhead.But light travels much faster than sound so, like delaye thunder froma distant lightning stroke, ameteor produced sound should onlybe heard long after th meteor streak was seen Asound explanation supported b laboratorytests is that turbulen plasma created by the meteor's passagegenerates very low frequency radio waves Travelingat light speed the radio waves reach the groundsimultaneously with visible light where they are strong enough to induceoscillating current andaudible vibrations in common objectslike grass, leaves,wire-frame glasses, and perhaps even dry, frizzy hair.
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