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Talk about a big bang: Giant meteor may have hit Ontario
October 17, 1996
Web posted at: 5:45 p.m. EDTSUDBURY, Ontario (CNN) -- Meteors can and do hit planets. Shoemaker Levy 9 slammed into Jupiter in 1994 with the energy of about 50 million Hiroshima bombs, and in its early history, the Earth was seeded with continuous meteor hits.
A meteor hit in the Yucatan Peninsula 65 million years ago is believed to have led to the extinction of the dinosaurs.
And scientists suspect that a massive meteor, the size of a small mountain, hit northern Ontario eons ago, leaving behind a bunch of strange-looking rocks, and dredging up enough copper and nickel to support a thriving mining industry.
However, scientists are still trying to prove the Ontario meteor theory. Geologist Wilfried Meyer, who works for the Ontario Provincial Government, says reading rocks is helping scientists piece together whether or not such a meteor did hit Sudbury 1.8 billion years ago.
Scientists have developed computer models to analyze the power of meteor impacts. They believe the Sudbury meteor, six to 12 miles in diameter, exploded on impact with the blast of 10 billion Hiroshima bombs.
"We ... believe that the meteor impact fractured the crust of the Earth to great depths and then rocks or magma, molten rocks from deep down in the Earth, came up and spread along between these younger rocks and the old crater wall," Meyer said.
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The impact shattered and scattered rocks, which rolled so much that they became smooth and round, Meyer said. Then, the rocks melded together, creating a 5,000-foot deep layer of rock that now is considered the Sudbury Meteor Basin.
Meyer offered a geological formation called "shatter cones" as evidence that a meteor hit Sudbury. Scientists long maintained that a volcano could have created the mineral deposits and conglomerate rocks of Sudbury, but when the shatter cones were discovered 30 years ago in Sudbury, they all but shattered the volcano theory.
"You can do this with dynamite explosions on a very local scale. You can do it in a nuclear explosions. But to the best of my knowledge, they've never been found associated with any volcanic explosion. So this is very strong piece of evidence of a meteor impact," Meyer said.
Modern-day collision could wipe out human race
If a large meteor hit the Earth today, the results could be devastating. For that reason, the U.S. Department of Defense is considering whether to monitor comet and meteor activity near Earth.
As Los Alamos National Laboratories senior scientist Greg Canavan explained, "If you knew where those objects were, then you would know whether any of them were potentially threatening."
In other words, to be forewarned is to be, hopefully, forearmed, so that we can do something to prevent a large meteor from hitting Earth. Scientists figure the odds of a meteor with the explosive energy of 300 Hiroshima bombs hitting the Earth is one percent every year.
So, according to Canavan, "It's not a matter of if they'll hit Earth, it's when."
Related stories:
- Meteorites carry stardust memories billions of years old - March 19, 1996
Related sites:
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- Asteroid and Comet Impact Hazards
- Space Telescope Science Institute: Comet Shoemaker-Levy 9 Encounters Jupiter
- Near-Earth Asteroid Tracking Home Page
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