Wednesday, February 22, 2023

Meteor Fireball Explodes Over 7 U.S. States
And Ontario : 'Green Pulsing Ball of Light'

Story by Jess Thomson • Yesterday 

Hundreds of people across the northern United States and Canada saw a fireball crashing through the night sky on Sunday night, lighting up the dark for a split second.

Watch Fireball Crash Through Night Sky Over Midwest
Duration 0:26   View on Watch

Reports of the fireball came from 197 residents across Illinois, Indiana, Michigan, New York, Ohio, Pennsylvania, Wisconsin and Ontario at around 9:51 p.m. local time on Sunday, February 19, according to the American Meteor Society.

Videos taken across the region show the fireball falling through the sky, flaring brightly before fading into darkness.

"My 8 year old son also [saw] it, and it was so bizarre it scared him," wrote one observer in Indiana on the American Meteor Society website.

"We both saw a quickly moving green pulsing ball of light that was very vibrant then faint then bright again all the while traveling along the same trajectory, bigger at first then the size diminishing as it went away from us on its path. It was definitely not a plane flying low. It was moving away from the airport, not towards it. A plane flying that close would have moved more slowly in the sky and probably be on its way to crashing. It was not at all like the meteors (Perseid meteor showers) we have watched yearly since 2020 nor like any of the dozens of "shooting stars" I've seen in my lifetime (I'm 46)."

"It was awesome and now I have so many questions. My husband thought he smelled ozone a few minutes after seeing it but I didn't smell anything," wrote another in Ontario, Canada.

Fireballs like this are caused by meteoroids burning up as they enter the Earth's atmosphere. Meteoroids are chunks of rock and ice from space, ranging massively in size from a tiny grain of dust to many feet across. When a meteoroid enters the atmosphere at high speeds—which can range between 25,000 miles per hour and 160,000 miles per hour—the friction with the gas causes it to burn up, becoming a meteor.

"As it comes into Earth's atmosphere at high speed (above 12 kilometers [7.5 miles] per second), it pushes the air in front of it, causing that air to become superheated (kind of like a shockwave), which in turn causes the surface of the rock to 'ablate'. Basically, the very surface layer gets super-heated, and vaporized," Jonti Horner, an astrophysics professor at the University of Southern Queensland, Australia, previously told Newsweek.

"As the thing continues to push through the atmosphere, it gets whittled away from the outside in by this ablation process—until friction with the atmosphere slows it to subsonic speeds."

Usually, only around 5 percent of the original meteoroid makes it to the Earth's surface, with the rest being vaporized during its dramatic descent. Meteors around the size of a softball can result in fireballs so bright that they are briefly as luminous as the full moon in the night sky.

This meteor was also bright enough to shine through the clouds, according to eyewitnesses.

"It was partially overcast, but it was still significantly bright through the light cloud cover," wrote another observer from Brillion, Wisconsin.



A picture of the meteor taken in Vicksburg, Michigan. Spalding Allsky Camera Network, Node73 - Pete Mumbower© Spalding Allsky Camera Network, Node73 - Pete Mumbower

"They also heat the atmosphere, so much so that it makes the path they follow glow," Mark Gallaway, an astronomer and science educator at the Royal Greenwich Observatory, previously told Newsweek. "It is this glow you see, as the meteor disintegrates, at something like 30 to 59 miles up. Larger objects, say the size of a pebble, will produce a bright meteor known as a fireball."

NASA estimates that about 48.5 tons of meteoritic material falls to Earth each day, but we only see the larger meteors, and those that fall during the night.

Most meteors have very little impact on people living nearby due to their smaller size. One example of a larger meteor that caused a significant degree of damage was the Chelyabinsk meteor that hit Russia on February 15, 2013.

This meteor is thought to have been around 55 feet long, causing large shockwaves as it collided with the Earth's atmosphere at roughly 43,000 miles per hour and exploded. The explosion was estimated to be as powerful as the blast created by between 400,000 and 500,000 tons of TNT, and resulted in widespread damage and over 1,600 injuries mostly due to broken glass, according to NASA.


"The Chelyabinsk impact in Russia exactly 10 years ago, was another story. It was about 17 meters across," Hadrien Devillepoix, a research associate at the School of Earth and Planetary Sciences, Curtin University in Perth, Australia, previously told Newsweek.

"The shock wave from Chelyabinsk luckily didn't kill anyone, but injured many because of broken windows due to the shock wave."

While this most recent fireball wasn't quite as dramatic as the Chelyabinsk meteor 10 years ago, it was still an impressive sight.

"This was huge and so bright. I have never seen anything like it," wrote one observer from Bucyrus, Ohio.

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