[meteorite-list] How far away can a meteor be heard?
From: drtanuki <drtanuki_at_meteoritecentral.com>
Date: Thu, 9 Jul 2009 07:39:59 -0700 (PDT) Message-ID: <387233.12473.qm_at_web53106.mail.re2.yahoo.com> List, I have the answer for thunder but not a meteor (I am guessing that they are about the same? 10miles or 16km Chris or anyone care to give the correct answer? Thanks! Thunder contains a somewhat cylindrical initial pressure shock wave along the lightning channel in excess of 10 times the normal atmospheric pressure. This shock wave decays rapidly into a sound wave within feet or meters. When thunder is heard from about 328 feet (100 m) distance, it consists of one large bang, yet hissing and clicking may be heard just prior to the bang (upward streamers). When heard at .6 mile (1 km) from lightning, thunder will rumble with several loud claps. Thunder is seldom heard beyond 10 miles (16 km) under ideal conditions. The sound of distant thunder has a characteristic low-pitched rumbling sound. Pitch, the degree of highness or lowness of a sound, is due to strong absorption and scattering of high-frequency components of the original sound waves, while the rumbling results from the fact that sound waves are emitted from different locations along the lightning channel, which lie at varying distances from a person. The longer the lightning channels, the longer the sound of thunder. Humans hear frequencies of thunder between 20-120 Hertz (Hz). However, there is a small amount, less than 10%, that is inaudible to humans produced from lightning, called infrasonic. Special listening devices are required to record these inaudible sounds. Sources: http://www.lightningsafety.com/nlsi_info/thunder2.html Best Regards, Dirk Ross...Tokyo Received on Thu 09 Jul 2009 10:39:59 AM PDT |
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