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Date: | Sat, 24 Nov 2012 18:25:49 -0500 |
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On 12th and 13th August 1883, an astronomer at a small observatory in
Zacatecas in Mexico made an extraordinary observation. José Bonilla
counted some 450 objects, each surrounded by a kind of mist, passing
across the face of the Sun.
Hector Manterola at the National Autonomous University of Mexico in
Mexico City has placed limits on how close the fragments must have been:
between 600 km and 8000 km of Earth. What's more, Manterola and co
estimate that these objects must have ranged in size from 50 to 800
metres across and that the parent comet must originally have tipped the
scales at a billion tons or more, that's huge, approaching the size of
Halley's comet.
Each fragment was at least as big as the one thought to have hit
Tunguska. Manterola and co end with this: "So if they had collided with
Earth we would have had 3275 Tunguska events in two days, probably an
extinction event."
http://www.technologyreview.com/view/425780/billion-ton-comet-may-have-missed-earth-by-a-few-hundred-kilometers-in-1883/
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