AdvertisementInfrasound is the acoustic sound waves emitted below the normal human hearing level, and while higher frequency noises are louder close to the source of things like nuclear explosions and rocket launches, low-frequency infrasound travels further. Infrasound, also known as low-frequency sound, describes sound waves with a frequency below the lower limit of human audibility. It covers sounds below 20 Hz and down as far as 0.001 Hz. The study of such sound waves is sometimes referred to as infrasonics. The team only examined rocket launches that occurred up to 3,100 miles (5,000 km) from an IMS station, but found the acoustic signals from rocket launches could sometimes be detected up to 5,600 miles (9,000 km) away.
AdvertisementInfrasound is louder than the all-time intensity of 1000 thunder storms.
( z0 loud :ARG2-of ( z1 have-degree :ARG1 ( z2 inflate ) :ARG3 ( z3 more ) :ARG4 ( z4 intense :ARG1 ( z5 storm :quant 1000 :mod ( z6 thunder ) ) :time ( z7 time :mod ( z8 all ) ) ) ) )
(z0 / loud
    :ARG2-of (z1 / have-degree-91
                 :ARG1 (z2 / inflate-01)
                 :ARG3 (z3 / more)
                 :ARG4 (z4 / intense-02
                           :ARG1 (z5 / storm-01
                                     :quant 1000
                                     :mod (z6 / thunder))
                           :time (z7 / time
                                     :mod (z8 / all)))))
AdvertisementInfrasound is louder than the all - time intensity of 1000 thunder storms .
z0 :ARG2-of z1
z1 :ARG1 z2
z1 :ARG3 z3
z7 :mod z8
z4 :time z7
z1 :ARG4 z4
z5 :mod z6
z5 :quant 0
z4 :ARG1 z5