Xenon, this is a huge find my friend. I don't know whether or not it is a drone or a UFO, but there is something flying in that picture.
I took the original image and zoomed in 300% using Mozillas zoom feature. From there I took a screen shot and opened with GIMP. Once I had the image open in GIMP, I darkened the shadows with the leveling feature, and zoomed in a bit further (as much as possible before image became over-pixelated)
This is what i came up with.
** I have NOT touched tampered with the image in any way, the craft you seen is exactly what is in the image.
I hate to piss on your fire, but there are other areas in those photos which have digital 'holes' where data is missing. This does not necessarily mean that wthese drones are not drones, but it does mean that others can point to these other black areas in the image and say the ones in the sky are similar areas of missing data.
Personally, I do believe that the rovers are monitored by someone else all the time and I have seen orb-like craft in images previously in the MER photos, but these ones may not be the best examples because the shape of the drones are a few pixels and we just do not know what 'algorithm' NASA put these photos through which might make them appear more 'drone-like'
On the surface of it, they do look like craft, but as I say, there are other areas of missing data in these images which give me cause to doubt a little.
Wow, awesome find! A while back on a thread called "falling or flying thing" we talked about some very similar
looking objects from the rear haz cams on sols 369 and 370. I've been looking for more of these ever since. And no way it's a speck on the lens either or it would be
in more shots. Just like that set you showed, they only show up on these. The first one I posted is a crop from the movie for comparison.