According to Space.com, a group of scientists in Scotland are publishing a paper in the journal Advances in Space Research that contemplates using asteroid dust to shield the Earth from solar radiation, thus mitigating the effects of global warming.

The idea has some problems, however.

Move an asteroid to L1 and then destroy it

The plan, according to Space.com, would be to capture an asteroid -- 1036 Ganymed, for preference -- and use a mass driver to throw out material from it to move it to the L1 point, the Earth Moon Lagrange Point that lay directly between the Earth and moon. Then the same mass driver would create a stream of asteroid dust that would surround the Earth and block out enough solar radiation to cancel out the effects of global warming, giving the world enough time to switch from a carbon based energy economy to something else.

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