* Astronomy

A huge impact crater was found nearly 200 feet below the surface of Lake Huron by geologists, along with a 58-pound chunk of carbonaceous meteorite and meteoric rock found at the same depth by crews drilling a pipeline.

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Can-Am Meteorite Crater

* Age (ma): ~500
* Diameter: 100 km
* Location: Under Lake Huron N 43° 14' W 82° 20'
* Dating Method: The interruption of the Grenville trends, the clear, regular, circular signature of the feature, and the interpreted magnetic source depths at the Precambrian surface, suggest an event post-Grenville and possibly as young as early Paleozoic

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