' And we saw debris fall past the window on the north side.

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The move, noteworthy for a country with a pacifist constitution, is aimed at shooting down any debris from the launch that might fall into Japanese territory.

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The moveable dams are raised in the fall to allow ice and debris to pass during winter and early spring.

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While the wood in the study was placed there by scientists, wood naturally finds its way into the ocean as dead trees fall into rivers and are swept out to sea, when storm debris is taken by surging waters and even from shipwrecks.

MSN: Wood feeds creatures of the deep sea - Technology & science - Science - OurAmazingPlanet | NBC News