Satellite maps of UFOs or water dropplets?

Factual Questions
1

With the recent release of Google’s map satellite feature, people all
over the world are pointing out interesting places to sight see. One
of the most interesting and controversial objects are several
artifacts that no one can quite make out what they are. Such examples
can be seen at
http://maps.google.com/maps?ll=26.748651,-80.189370&spn=0.0,0.0&t=k
http://maps.google.com/maps?ll=34.134822,-117.603793&spn=0.0,0.0&t=k&hl=en
http://www.googlesightseeing.com/2005/05/18/ufo-update/ for original discovery.

People have speculated them to be anything from weather ballons, swamp
gas, water drops, and UFOs.

Any idea on what they are?

2

Where was the sun when these pictures were taken?
The spots look like they could be some variant on Gegenschein or a Glory.
There are all sorts of Atmospheric phenomena that could be coming into play.

3

The position of the sun is easily estimated by looking at the shadows on the trees. Looks to be nearly south and moderately high but not overhead.

4

If that were the case, shadows should all point away from this glow. This is clearly not the case in the above linked images.

I haven’t read through the third link but I looked at the image links on there. As far as I can tell:
[ul]
[li]They are all circular.[/li][li]They all have a color gradation, one side blue and the other side white. The middle part seems to be close to background (landscape) color.[/li][li]The direction of the color gradation is almost always north-south.[/li][li]There seems to be no correlation with the position of the sun.[/li][/ul]

I’d guess it’s either an optical artifact (water droplet, imperfection in the lens or window, etc) or a software artifact, but beyond that I have no idea.

5

Am I the only one who thinks maybe this is the same dirty lens on the same satillite, that’s taking pictures along to same little path it takes around our planet?

6

You’re probably not the only one thinking that, but according to maotx’s last link you’re wrong. That link says the pictures are taken by airplanes instead of satellites.

BUT, I think a dirty lens sounds a little more likely than alien spacecraft.

7

If these are all airplane pictures that have the artifact (as they seem to be), then my guess would be a water droplet on the lens. Lenticular clouds generally form as a part of a larger cloud system, and these whatevers-they-are seem to be mostly transparent (since their colors mostly match the background).