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Mars Mercury Venus Earth’s Moon (S. Pole)
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Mistastan Lake, New Foundland, Canada 28 Km 38,000 years
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Barringer Meteor Crater, AZ 1.18 km 49,000 years
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Wolf Creek, Australia 0.875 Km 300,000 years
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Bosumtwi, Nigeria 10.5 Km 1.3 Million years
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Roter, South Africa 2.5 km 5 Million years
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Karakul, Tadjikistan 45 Km < 10 Ma
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Chicxulub, Mex 170 Km 65 Ma
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Clearwater Lakes, Sask. 32 km/22km 290 Million years Deep Bay, Sask. 13 km 100 Million years
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Gosses Bluss, Australia 22 km 142.5 Million years
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Aorounga, Chad 17 km 200 Million years
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Manicougan Lake, Quebec 100 km 212 Million years
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Radar Image of NEO 1999JM8 Missed Earth by 5 million km in 1990, 6 million km in 1999 Average diameter 3.5 km
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80 million trees knocked down over 2,150 square kilometres (830 square miles Tunguska Event, 1908, Russia
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Tunguska Event 1908 Equivalent to a 100 MT Nuclear Bomb Blast
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Question If cratering rate on Earth is same as our Moon, why are their so few craters preserved?
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What is wrong here?
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Apollo 14 site spherules (~ 0.2 mm diameter) Argon40/Argon39 dates (accuracy ~ +/- 200 MY)
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Apollo 14 site spherules (~ 200 micro-meters diameter) Argon40/Argon39 dates (accuracy ~ +/- 200 MY) => 26 Ma periodicity
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1 BY averaging bins Black and opaque spherules only
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Question: If cratering rate on Earth is same as our Moon, why are their so few craters preserved? Answer: Erosion
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