2 birds with 1 stone.

>Last Monday the BBC had a report on exotic ways of solving global warming.
>One report was about an astronomer who was doing the preliminary
>calculations on placing mirrors in orbit to shield the earth of 2
>percent of the sun's rays. He came to a cost of about a trillion
>dollars He used a maglev launcher to place the mirrors in
>orbit. The amortized cost for LEO was 10 dollars a kg. Instead of
>just mirrors why not SPSs to shield the Earth from 2 percent of
>Sunlight. And if that is too much energy for the Earth to use we
>could use the rest for chemical processes to pull out CO2 from the atmosphere.

That was probably this report:

Feasibility of cooling the Earth with a cloud of small spacecraft
near the inner Lagrange point (L1)
http://www.pnas.org/content/103/46/17184.full

Best wishes,

David Brandt-Erichsen
National Space Society Volunteer Website Team
Webmaster of:
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