Since 1997, residents and tourists alike have reveled in a mysterious sound emanating from a Chinese square. When fireworks are set off near the Southern Jiangsu Victory Monument, a seconds long echo — that sounds uncannily like a bugle — can be heard.
Some attributed spiritual significance to the sound because of the monument's proximity to a sacred Taoist mountain. Scientists, however, have found that there's a straightforward physics explanation behind the bugle-like sound.
You can hear the bugle-like sound after every fireworks "pop" in the video below.
Sihui Wang and colleagues from Nanjing University in China set out to unravel the mystery behind the "Maoshan Bugle." Local media had found no physical explanation for the bugle sound for years, prompting the research team to examine the square more closely.
The square has six sets of approximately 50 steps around it. And the team found that this grating structure of steps created an interference effect when when the fireworks sounds bounced off of the steps.
The team recreated a theoretical model of the grating structure, and found that it produced a similar bugle-like echo as well. Thus, the team has shed some light on the mystical Maoshan bugle.
"The physics is not mysterious after revelation," Wang told Physics Central in an email.
Wang hoped to present his research during the American Physical Society's upcoming March Meeting in Boston. Unfortunately, he won't be able to make the trip over to the U.S., and his talk has been withdrawn. Nonetheless, Wang still wants to share his unique discovery with the public.