Big mirror in orbit.?

Question

I was just wondering if there were any projects that any government was working on that involved using a big mirror in space to light up or perhaps warm up a certain area of the earth. Just a random question, I searched a bit on the internet but came up empty.

Answer 1

No, not that I know of.  

First the logistics would be ridiculously involved, plus there is also some credence for the whole super villain burn up cities idea.

Answer 2

Here's another link you can try...it's pretty interesting.

http://astroprofspage.com/archives/1265

Answer 3

One practical use for a big mirror would be in deflecting asteroids.  You'd use a parabolic reflector, stationed to point to a single spot.  That spot on the asteroid would vaporize, acting as a rocket, pushing the object to a new orbit.  The mirror wouldn't have to be absurdly accurate like a telescope mirror.  And, it would have to be huge.  So a light weight foil on a light weight umbrella structure might be all one would need.

It seems to me that it would be cheaper to use ground lighting than shine light from space.  The light from space may be free, but getting the mirror up there is going to be expensive.

Answer 4

I don't believe there are any such projects occuring. It would be very dangerous to attempt such a feat even with years of carefully studying the effects it would have on global weather. It's said that a butterfly on one side of the earth can cause a hurricane on the other side.

Answer 5

The Earth is already warming up. Adding more sunlight to it is probably the LAST thing we want to do. Mars, now, could do with a bit more heat, but putting a large mirror in orbit around it would be quite a challenge. Not so much putting it there, but keeping it there. The solar wind and light pressure would make station-keeping a difficult and energy-intensive task. It would need to have some rockets on it to keep it from being blown away, those rockets would have to be regularly refueled......sorry, can't be done with current capabilities.

Answer 6

I don't thinks that's a good or plausible idea. Global Warming already warms the Earth. I think something to cool it down would be much better. We don't have the technology to build a very large accurate mirror and it would cost too much.

Answer 7

Russians tried something like this about 15 years ago.   I don't think it work out well. See link