Quote Originally Posted by littleindiangirl View Post
Nasa is a part of the governement. Is their explanation not good enough?
NASA says that they are contrails, and that contrails are just water vapor, or clouds. Then they show IR pictures of the water vapor and clouds over the U.S. Then they show "enhanced" IR images of the same space which show some weak clouds and very highly visible contrails that trump all the other water vapor in the atmosphere. I couldn't find an explanation for why the contrails were so pronounced in the enhanced IR images, when they are supposedly the exact same thing as the rest of the clouds. So I'm back at square one. There might be a good explanation, but I didn't see one.

http://www.nasa.gov/centers/langley/...04/04-140.html

Those probably are contrails, at least for the most part. But that doesn't prove they don't exist, or that they aren't being used to a smaller extent.