Yup, I saw the grainy version on /r/aviation a few days ago and thought "yeah, right". The photo is probably a frame pulled from a vid, to score the frame shadow projected onto the balloon like that. Also shows how well the solar panels' orientation was maintained. Surface normal vector pointed straight towards the plane/sun.
Buddy of mine pointed out that "coming around" in a U-2 is more challenging than most as the difference between "wings come off" and "stall" is about 10 knots. Which means you have about about 2% variation above and below cruise in a straight line... and less than that in a turn, as one wingtip is going more than cruise and the other is going less. I pointed out that a GoPro Hero 4 gives you a 4k image at 120Hz. A U-2 is 63 feet long and cruise speed is 630 ft/sec; there's either about a fifth of a second in which to get that one good shot, or you rip it at 4k and you have a dozen or more shots with 'muricashadow flying proud on that balloon. And that's a GoPro. I can only imagine what purposeful cameras that thing has on it. When Frank Powers got shot down it was taking pictures of the ground with 20cm resolution from that high up.