Fun lesson on sun-synchronous orbits (the orbit for almost all optical satellites)
SSOs are designed to pass at approximately the same time every day so that the lighting conditions are similar.
If you have the lighting conditions, you can work backwards to get the orbital plane. https://twitter.com/M_R_Thomp/status/1246150316036370432
When I first saw this image, I assumed that it was taken by @Maxar (formerly DigitalGlobe) or some other commercial company that provided high-resolution imagery in 2011. But in 2011, all of their imagery satellites were in approximately the same plane.
And this orbital plane would pass over Abbottabad at around 11:00am local time (6am UTC). But look at the shadows in the original image. They're cast towards the East, which means that they were observed sometime after solar noon. The timing doesn't match up.
DigitalGlobe released imagery from WorldView-1 of the Abbottabad compound, and you can see that the shadows are cast to the West. This image was taken around 6:12 UTC on January 15th. https://www.space.com/11543-osama-bin-laden-compound-satellite-photos.html
From January until these images were released in May of 2011, that solar geometry barely changes for any image that DigitalGlobe satellites take. That's literally why a sun-synchronous orbit exists.
So given that the image had to be taken sometime after solar noon, we're looking for a satellite in a plane a little bit further to the West that would pass over Abbottabad a few hours later.
I'd say that the resolution of this released image is at least 1 meter per pixel. A review of commercial satellites capable of that resolution in 2011 doesn't yield too much. There's an Israeli satellite called EROS-B that has a resolution of ~0.7 m/px in a promising plane.
But what I'm much more interested in are the NRO's "big birds": KH-11 spy satellites. In 2011, there were 4 on-orbit. Two in planes that have earlier pass times, and two in planes with later pass times. They're shown here in red.
Now, a closer look at the solar geometry. Given that we have a direction for North, we can come up with an estimate for the solar azimuth based on the shadow of a tall, thin object. Here, I use what looks like a telephone pole to get a shadow angle of ~38 degrees East of North.
This solar geometry can be used to constrain when the photo was taken to specific times of every day. If you allow for even a large margin of error like 10 degrees in measuring these angles, that still narrows it down a lot.
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