Annmarie Throckmorton, M.A.
- Apr 27, 2019

The Sound Of Comet Hale-Bopp

At the time the comet Hale-Bopp was brightening high over Earth's horizon*, I was a contractor working at Mitsubishi Motor Manufacturing, of America, Inc. My project was to create new, plant-specific teaching materials for an apprenticeship program that my supervisor was developing. I gathered technical information primarily by interviewing machine operators, mechanics, electricians, and foremen, then I wrote standard operating procedures within each of the six maintenance departments of the plant: Trim & Final, Production Tooling, Press Plastics, Paint, Body Maintenance, and Utilities. The manufacturing facility was located at the edge of the small college town of Normal, Illinois, adjacent to regularly farmed fields. It was a beautiful little town in a lovely, healthy setting.

I read that comet Hale-Bopp had brightened to its maximum in the local newspaper, The Normalite which advertised itself as "The human side of the news of the Normal" (sic, now defunct). That evening I brought my parents outside to stand on the sidewalk beside their house and look for the comet. It was March and chilly. Within a few seconds of scanning the dark, moonless sky we saw the comet. And I heard it! I actually felt viscerally the strange vibrations of comet Hale-Bopp, and my ears interpreted it as a ominous reedy hissing. It was unmistakable, loud, I could hear it over my parents talking excitedly about the comet.** Comet Hale-Bopp was startlingly bright, and it had the longest tails I have ever seen on a comet***.

The sound of the comet was terrifying, it was as if the cosmic gods were out there in the vast blackness of space, blowing through glittering comet tail blades to create that reedy whistle a blade of grass makes when you blow over it, but the gods failed to make the comet tails whistle, and they only hissed and crackled menacingly. When I pointed out the scary noises to my father and mother, he said he heard it too and she hustled them both back inside the house. Nature had not been gentle with them in the past and she was taking no chances. Lightening had once struck at them while they were sleeping in their own bed. Of course I found that hard to believe, so my mother showed me the small, charred hole in their bedroom ceiling (directly over their bed). The lightening had not touched them but it had cracked their roof ferociously and had lit up their bedroom with a tremendous boom. Restoring that section of their roof to watertight was quite expensive because the lightening had zigzagged randomly on its way in.

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* "By early 1997 (comet Hale-Bopp) had become a spectacular object in the nighttime sky and (received) attention from around the world...it was as bright as the brightest stars in the sky, and became one of the brightest comets to appear during the 20th Century. Its high brightness, long duration of visibility, and convenient location in the evening sky after dusk made Hale-Bopp the most widely-observed comet in history."

Source: www.swisr.org/hale-bopp.html

** USA Today, "What does a comet sound like? It sounds like this..."

"Technically speaking, the sounds are thought to be oscillations in the magnetic field around the comet, according the NASA."

Source: https://www.usatoday.com/story/tech/sciencefair/2014/11/14/rosetta-comet-sound-philae/19017981/

*** "Perhaps the most exciting feature of Hale-Bopp is its unique tail. Like most comets, it has two tails that can be seen by the naked eye under the right conditions: a bright dust tail, which is created by the reflection of sunlight on the dust streaming from the comet, and a fainter ion tail, which is composed of electrically charged atoms swept from the comet by the solar wind. But in April 1997, a group of European astronomers using one of the world's most powerful telescopes at La Palma in the Canary Islands, found a third tail. Setting spectroscopic instruments to exclude all light from the comet except the yellow light emitted by sodium atoms, the scientists were surprised to see a narrow third tail located near the ion tail. They estimate that this new sodium tail, which is not visible to the naked eye, is about 373,000 miles wide and about 31 million miles long."

Source: https://www.pbs.org/wgbh/nova/spacewatch/comets.html