Mysterious booms, annoyingly persistent hums, and underground mechanical rumblings that defy explanation
- In January, 1999, a loud boom at 12:15 a.m. disturbed the residents of Colorado Springs and Denver. Some witnesses said the noise was accompanied by a flash of light in the sky. There was no electrical storm. Although it could have been a sonic boom, the military denied any military activity in the area.
- On January 10, 1999, dozens of people in Fairfield, Ohio reported a stunning, explosive sound. No cause was ever discovered.
- Thousands of homes were rattled by two huge, mysterious booms 30 miles southeast of Los Angeles just before 10 p.m. in May of 1998. Residents described the sounds as explosions, earthquake noises, and thuds. The two booms occurred about five minutes apart.
- Two very loud skyquakes startled hundreds of people on the beaches of Ocean City, Md. on July 30, 1998. No planes were in sight, and the sounds seemed to be coming from some miles offshore.
- A mysterious boom reverberated through Narragansett Bay, R.I. on August 1, 1998 at 9:30 p.m. Investigating officials could not find the source of the noise.
- On Sept. 16, 1997, the campus of the University of North Carolina at Chapel Hill was rocked by a boom that shook the ground and registered 1.1 on the Richter scale. Readings from ground-monitoring equipment showed that the energy did not come from the air, ruling out a sonic boom.
- On December 17, 1997, a huge aerial blast rattled windows and blew open storm doors in Rogersville, Mo., a town 13 miles east of Springfield. Again, the Air Force denied the possibility of a sonic boom caused by one of its aircraft.
These are just a few recent examples of a fairly common phenomenon - loud, earth-shaking booms with no apparent cause. They are often labeled as mystery booms, sky booms, or skyquakes, and although there could be quite prosaic explanations for the explosive sounds - sonic booms, small earthquakes, even exploding meteors -- investigations always come up short for conclusive explanations.
THE TAOS HUM
The Taos Hum is a faint, low-frequency humming noise heard in and near the town of Taos, New Mexico. Not only is the hum's source a mystery, but its peculiar qualities are as well: only about 2 percent of Taos residents - about 1,400 people - can hear it. The low hum - between 30 and 80 Hz on the frequency scale - has been described by hearers as sounding like a diesel engine idling in the distance or having a slow beat-note sound. Some people perceive it as being louder indoors than outdoors.
More mysterious still, some hearers who are bothered by the sound have tried earplugs and other acoustic quieting devices to block it out - to no effect. Investigations by scientists, including some from the prestigious Sandia National Laboratories, have failed to find a source or even a plausible explanation for the phenomenon. One theory is that the source is the U.S. Navy's ELF (extra-low frequency) communications system that is used to communicate with its submarine fleet. The Navy, of course, accepts no such responsibility.
Next page: Underground; Sounds of Hell