It is one of the biggest impact craters on Earth - and until now, scientists have been unsure how it got there. The Sudbury Basin in Ontario, Canada, is 39 miles long and 19 miles wide - and 9.3  miles deep. Researchers have been unsure how it formed - but now say it was a giant comet, not a meteorite as previously thought. They say it was caused caused by a comet colliding with our planet over 1.8 billion years ago. The Sudbury Basin in Ontario, Canada, is 39 miles long and 19 miles wide - and 9.3 miles deep. It was formed by a comet hitting Earth 1.8 billion years ago, researchers have found.
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Ontario crater is 39 miles long and 19 miles wide, and 9.3 miles deep
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Was caused caused by a comet colliding with Earth 1.8 billion years ago
ntario,
ntario,
Ontario
Due to the high mineral content of its soil, the floor of the basin is among the best agricultural land in @placeholder.