Sonic Booms from Fireballs

Many video systems apply a Camcorder as the recording device. The advantage of their use are audio records parallel to the video image of the scene. With that you are not only able to catch the cry of observers having just witnessed a fireball, but sometimes the fireball itself!

During their Leonid expedition to Spain Dutch observer from the DMS had the fortune to record a rare sonic boom of a bright fireball (photo below) that appeared on November 17/18, 1995. Four minutes after the visual event two loud detonations were heard at Zafarraya and could be registered from the video system built by Klaas Jobse. Unfortunately the quality of the recording was low due to different noise sources, however, after low pass filtering the signal the booms became much clearer. The graph above shows the amplitude of the recorded sound event.