I missed Pete Worden's talk on the use of lunar resources to alleviate global warming, on the first day of the Space Frontier Conference, because I was splitting time between it and work in El Segundo. But it was quite interesting, and Jeff Foust has a report on it in today's The Space Review.

It has this curious exchange, though:

...someone asked Worden after his speech, if this system is privately developed, what’s to prevent someone from blocking ten percent of sunlight, instead of two, and selling—or ransoming—access to it? “That’s where governments have to say that there has to be some level of regulation,” Worden admitted. “Unlimited capitalism is just as evil as unlimited government.”

This has nothing to do with "capitalism," bridled or otherwise. It would be illegal extortion, plain and simple, and the act of a criminal, not a capitalist.

This idea is very interesting. The idea that mankind could put a device in space of that size to manipulate our environment is astounding. Now if he could put his brain and other people's resources to work to PROVE Global Warming exists...it would take the same amount of time, apx 30 years, and a lot less money to determine his deflection device isn't necessary because global warming doesn't exist.

Mac

To argue global warming doesn’t exist is as pointless as arguing that giant meteors won’t hit the earth. Both are within the realm of possibility if you take the long view i.e. many generations. However I have always believed that given any need, we have the best chance of solving that problem with a profitable solution. After all we are the cleanest most efficient country in the world not because environmentalists have driven our technology to that end, it’s because efficiently using everything is inherently more profitable. We have a restaurant chain that now serves Bison. If they are successful the Bison population will grow exponentially. Because the animal will be valued, more their numbers will grow. Like it or not that’s how capitalism works. A space shade may actually be a profitable and useful thing one day. So might a fusion power source or a 90 percent efficient solar cell. The point is that no problem is ever solved by those who’ve spent their whole lives screaming there’s a problem. It’s solved by those that serve humanity by serving themselves.

I agree, and I'll order some bison, though I prefer ground for cooking... (grin).

However, even though a space shade may indeed be profitable and useful in the future, using a myth to propose its building seems stupid. Most of the liberals out there believe we went to war for no just cause, but I bet they wouldn't oppose a 2-3 trillion dollar construction based on the same foundation.....

Mac

We have a restaurant chain that now serves Bison.

In my area, we have three: Ruby Tuesday, Smokey Bones, and Ted's Montana Grill.

The last, owned by Ted Turner, I avoid for reasons unrelated to the menu -- but Ruby Tuesday has even recently expanded the number of bison-meat offerings on its menu.

The basic idea is great, but it seems like there should be ways of going about it that don't involve billions of satellites and trillions of dollars. Just tossing stuff out,

-spacecraft that fly to L2 then break in two and unreel a humongous sheet of CNT-reinforced mylar between them. They spin around their common center of gravity, keeping the sheet, maybe hundreds or thousands of miles long, stretched tight between them with the rotational plane orthogonal to the sun. Repeat ad nauseum. Maybe it would take a few hundred or a few thousand instead of a few billion satellites.

-now coat them with that new non-organic solar-cell goop and put masers on the spacecraft halves. They shade the Earth _and_ provide power!! Maybe there's a thermodynamic catch, but hey, I'm an idea man.

-plain old solar sails of the type talked about for decades now. They tack their way to L2 and then tack to stay in the correct position relative to Sun, Earth and each other. If each sail is a square km, you need only two million, instead of ten billion, to get the same amount of shade.

There's still the thought that global warming isn't occurring. (Sure looks like a tree-hugging Luddite anti-capitalist anti-Western wet dream to me.) Even if it is, there's still the thought that, um, is it really a bad thing? Then there's the thought that Ray Kurzweil is right, and solving this problem will be a trivial exercise in a few decades.

An interesting version of the idea is by
Paul Dietz, see http://groups.google.com/group/sci.space.policy/msg/125ce35282e4426e?as_umsgid=nbqdnZZ-kvD3gxzd4p2dnA@dls.net

Quote:
"My BotE calculations suggest
that surprisingly little mass need be moved to the Earth-Sun L1
point to significantly reduce insolation at Earth, if you arrange
the system properly.

The idea I have would be to mine the moon for materials that can
be vaporized near the Earth-Sun L1 point. The atoms and small clusters
in the vapor would scatter sunlight in certain narrow bands by
resonance scattering or fluorescence. The gas would be accelerated
toward Earth by light pressure, doppler broadening the bands (the
higher the acceleration the better.) "

Why dont we just drop a few surplus nukes into a large volcano? The volcanic ash ejected into the upper atmosphere should provide atleast a couple of decades worth of cooling.

But that would be man-made pollution then...and...and global warming...and. If we really need a giant solar shade, why not just buy sunscreen?