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Have you seen reports about “killer asteroids flying by Earth”? Naturally, many are concerned that Earth may not always be so lucky. Should we be worried? Bob Berman, astronomer for The Old Farmer’s Almanac, explains all in his usual straightforward way.
First things first. In the last couple of weeks, I’ve seen reports of an asteroid heading near Earth, one passing much closer than even the Moon. One major publication states, “You may be able to see” these “killer asteroids.” Is this a joke?
In reality, both of these NEOs (near-Earth Objects) are passing us during the daytime! No matter how large their telescope is, anyone cannot see either of them—a bunch of media clickbait.
There have not been many asteroids close to Earth. Let’s take a look …
Asteroids Near Earth
Yes, millions of years ago, an asteroid probably wiped out most of our planet’s animal species, and it is the reason you see chipmunks rather than raptors out your window. This was on the Yucatan coast.
The biggest asteroid explosion in recorded human history occurred in 1908 over Russia (in a remote area of Siberia). Called the ‘Tunguska event,’ the blast had the impact of 185 Hiroshima bombs, with over 80 million trees filled, and the land the size of London was flattened.
In North America, there’s a record from September 29, 1938, when a carport roof in Benid, Illinois, was penetrated by a four-pound meteorite, which then imbedded itself into the seat of a Pontiac and dented the muffler. But there were no deaths.
In 1954, North America’s luck ran out. In Sylacauga, Alabama, Ann Hodges was sitting on her couch when she saw a meteorite burst through her ceiling and strike her on her upper thigh. The resulting bruise—nothing worse—marked the first-ever US meteor impact that resulted in medical care.
More asteroid incidents occurred in houses in Wethersfield, Connecticut, where roofs were penetrated in 1971 and again in 1982. I interviewed the 1982 victims, Bob and Wanda Donohue, who said they’d been watching TV (“Mash,” they explained) when the loudest crash they’d ever heard emanated from the next room. The hole in the ceiling and scuffs in the carpet were explained by the dark 10-pound meteorite lying under the table that they generously donated to a New Haven museum.
Then, on October 9, 1992, 18-year-old Michelle Knapp in Peekskill, NY, heard a bang outside her house and found the trunk of her 1980 Chevy crushed. The culprit meteorite lay under the car. But, as so often happens in life, bad events can end up with happy outcomes. Ms. Knapp accepted an offer for $67,000 for the meteorite, with the buyer insisting that she include the car as well. A 12-year-old damaged Malibu? “Take it,” she said.
The Peekskill, NY Chevy and the meteorite that went completely through it in 1992.
The Chance of an Asteroid Strike?
It turns out, on average, a home is penetrated every 1-1/2 years in North America alone. If it doesn’t burn completely to dust or explode in the air, an asteroid weighing less than 100 pounds is slowed by air friction to a terminal speed of around 250 miles per hour when it hits the ground. That’s proven to be enough to penetrate the roof and the ceiling below, but rarely any additional floors.
In more recent times, this is what happened on March 26, 2003, in a Chicago suburb, when the meteorite hit a teenager’s printer and just missed the boy by a few feet, and in Lorton, Virginia, in January 2010.
We shouldn’t be too surprised. We can see incoming space debris burning up as it penetrates our atmosphere every night. The most visible ones are the size of apple seeds.
This Almanac, of course, alerts readers to major annual showers that bring a meteor-a-minute to view. But any night after midnight, Earth’s spin has rotated your home to our planet’s leading hemisphere as we zoom through space at nearly 19 miles per second, producing an average of six visible meteors an hour as we slam into them.
The Danger of Asteroids
But our present focus is on danger. This brings up the event that produced the most injuries. This happened back in Siberia again, and was an event we may all recall, since it was on February 15, 2013. That’s when an asteroid exploded with a force equaling several atomic bombs 18 miles above the city of Chelyabinsk, Siberia. Weirdly, it happened while I was watching a known, expected asteroid as it narrowly missed Earth at the trifling distance of 17,000 miles.
That known asteroid, about half the size of a football field, crept its way past our world at the leisurely speed of 4.8 miles per second, approaching us from the south. By contrast, the meteor that exploded over Siberia that same winter day came from the northeast. That one, heading our way from the Sun’s direction and thus impossible to spot in advance, was speeding over 10 miles per second, which matters because its velocity mostly determines an object’s explosive force. Experts estimate its size from that of a car to a locomotive.
But here’s the practical takeaway. The injuries in Chelyabinsk happened because, after the overhead flash, a strange white streak lingered across the sky, so everyone went to their window to have a look. When the shock wave struck between one and three minutes later, the windows shattered, resulting in over a thousand cuts by glass.
Enough to make us worried? Hardly. Most incoming comet or asteroid impacts or air bursts happen over oceans, and even then, an event of great destructive force occurs only once every one to four centuries. As for impacts that could wipe out the human race, figure maybe one every 100 to 300 million years.
It’s far more likely you’ll be done in by chronic overeating. Still, if you ever see a sudden brilliant light in the sky, wait a few minutes to check it out. Or, at minimum, if you simply must look overhead, first open the window.
Bob Berman, astronomer editor for The Old Farmer’s Almanac, covers everything under the Sun (and Moon)! Bob is the world’s most widely read astronomer and has written ten popular books. Read More from Bob Berman
"It’s far more likely you’ll be done in by chronic overeating."
I feel so called out right now! (Kidding hahaha.)
Thanks for the article! I'm glad no one's ever been killed or seriously hurt by being struck. It's a terrifying thought that you're not safe from meteors anywhere except deep in a cave or underwater.