| ABSTRACT
The Peoples' Republic of China
conducted the last atmospheric nuclear weapon test in 1980.
Despite this, two of UAF's infrasound observatories (one here
on campus and the other on the Ross Ice Shelf), are designed to
monitor for just such testing activity as part of the verification
regime of the Comprehensive Nuclear-Test-Ban Treaty.
Happily, nature has provided us with a steady supply of surrogate
blasts in the atmosphere with which to test our monitoring systems. Small
objects (< 50-100
m) collide with the Earth's atmosphere quite frequently, but
do not typically strike the ground as a single body. Rather, they
explode as a result of sudden heating resulting in a fireball or
bolide. Bolides can still do considerable damage upon
impact — the Tunguska event was likely such an impact.
Such events are often expressed in the equivalent explosive
yield in TNT; a Tunguska-class event is considered to be of
order 10 MT. In this talk I'll cover the basics of bolide
impacts, how they are monitored and the contribution of infrasonic
data analysis to constraining the flux of bolide impacts.
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