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Hear the First-ever Recording of a Meteorite Slamming into the Ground – Sky & Telescope

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This security camera video records the sight and sound of a small meteorite impact at a home in Marshfield, Prince Edward Island on July 25, 2024. Courtesy Joe Velaidum and Laura Kelly

Every day, something like 100 tons of meteoric dust and sand-sized particles strike the atmosphere. A smaller but still significant amount of pebble-sized meteoroids continually pelts the planet, too. While the increasing use of home security cameras has led to a flood of videos of brilliant fireball trails and flashes in recent years, no one had ever recorded the sound of a meteorite impact. That changed on July 25, 2024.

A small stony meteorite created this starburst pattern when it struck a stone walkway outside a home in Marshfield, Prince Edward Island last July. Courtesy of Joe Velaidum and Laura Kelly

That day, Laura Kelly and Joe Velaidum returned to their home after an evening walk in the community of Marshfield, located near Charlottetown on Prince Edward Island (PEI), Canada. On the walkway they noticed something odd —an explosive pattern of gray dust that looked as if someone had taken a friable rock and thrown it with great force against the stone. Not knowing the cause, the homeowners brushed off the rock particles and rinsed the stone clean.

Scientists at the University of Alberta analyzed the meteorite and classified as a stony H5 chondrite. The “H” indicates a high iron-nickel metal content, and the “5” (on a scale of 3 to 6) indicates that the meteorite’s parent asteroid had been significantly modified by heat and pressure.
University of Alberta Meteorite Collection

Later, after reviewing footage from their home security camera, they suspected the splat may have been caused by a meteorite impact. They returned to the scene, collected about 7 grams (¼ ounce) of the rocky material with a magnet and vacuum and then shared the video with the University of Alberta Meteorite Reporting System. They also connected Chris Herd, curator of the University of Alberta Meteorite Collection, and sent him samples of the suspected space rock. Herd confirmed that was in fact a meteorite.

“As the first and only meteorite from the province of PEI, the Charlottetown Meteorite sure announced its arrival in a spectacular way. No other meteorite fall has been documented like this, complete with sound,” Herd says. “It adds a whole new dimension to the natural history of the Island.”

Chris Herd measures a small divot in the stone caused by the impact.
University of Alberta Meteorite Collection

Serendipitously, he had planned a trip to the Island just 10 days after the meteorite fall and made a side trip to visit the couple and document the scene the following month. In the meantime, Velaidum had collected additional fragments, and with Herd’s help found more, for a total of 95 grams. The couple donated a portion of the precious material to the university for further study and for inclusion in its meteorite collection.

Analysis revealed that the new arrival — since named Charlottetown — was an ordinary chondrite, the most common type of meteorite found on Earth. About 86% of meteorites collected to date belong to the class. Ordinary or not, the sight and (recorded) sound of the new arrival sets it apart from all prior cosmic arrivals. I’m curious how you would describe the sound? I hear shattered glass.

We can actually see the incoming meteoroid moments before impact. In the first view (left) it’s a single object. At right, there appear to be two pieces. Did a smaller fragment followed just behind the larger one or did it spall off? It may also be an artifact from the video recording. Comments welcome! Courtesy of Linda Kelly and Joe Velaidum

Look closely at the video and you’ll spot the meteorite prior to impact. It appears in two frames, which I’ve screenshot and posted here. Notice in the second frame that a small fragment appears to have separated from the main meteorite. You might be wondering why the space rock didn’t blast a hole in the ground. First, it was small. By comparing meteorites of the same type and approximate weight from my own collection, I estimate roughly 6-7 centimeters (2-3 inches) across. And though the interplanetary traveler entered the atmosphere at between 44,000 and 145,000 kilometers per hour (27,000 and 90,000 mph), by the time it hit the ground air resistance had slowed its speed to around 100-200 meters per second (220 to 450 mph). That’s still fast but nowhere near cosmic velocity.

Heated by their plunge through the atmosphere, meteorites often develop a black fusion crust which covers their pale interiors. Chondrites like Charlottesville are composed primarily of silicates that often resemble fresh cement. That’s why the impact fragments from the Canadian fall were mostly gray in color. Left: A slice of the Demsa, Nigeria meteorite (H6), which fell on Oct. 31, 2006 (note the black crust and numerous iron-nickel flecks). Right: The pale interior appears in breaks in the fusion crust of Hammadah al Hammra 346, an L6 chondrite.
Bob King

Velaidum was deeply affected by the experience. He related that had been standing in the spot the meteorite hit just a couple minutes before the strike. Had he lingered longer before taking the dogs for a walk he could have easily been struck by the projectile.

“I feel so fortunate to be alive!!,” he said. “There are no words to express how I feel about this experience: this meteorite, which has travelled for hundreds of millions of kilometers and somehow, miraculously, misses hitting me by mere minutes as it smashes on our doorstep and is caught on video and, importantly, with sound — for the first time in the history of the Earth. There are no words . .

Article by:Source: Bob King

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