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by Loughla 638 days ago
So that was how long ago? I guess the super zoom satellite footage from movies might not be unrealistic like I thought. . .
3 comments

There's a hard physical limit (the Rayleigh criterion) on the resolution of an optical system by how big the open end is. You won't get "super zoom" capabilities without a satellite the size of a stadium. https://en.wikipedia.org/wiki/KH-11_KENNEN#Resolution_and_gr...
What about multiple satellites working to get one image?

Like the arrays we have on Earth pointing to space, but instead, arrays on space pointing to Earth.

I know there probably isn't that many KH-style satellites to do it, but would it be possible?

The alignment has to be better than half a wavelength. That's doable for RF, but for optical telescopes you're talking nanometers. That's not possible (currently or in the foreseeable future) for a spacecraft constellation.
Amusingly enough, there's been some groundwork laid here by gravity wave interferometer constellations: https://en.wikipedia.org/wiki/Laser_Interferometer_Space_Ant...

You could imagine a deep-infrared mission (longer wavelength, to soften the alignment requirements) launched into deep space (Jupiter+) where both the solar wind density is lower (reducing space weather perturbations) and reduced solar flux would reduce heat loads on the structure, (objects in Jupiter orbit get 3.6% as much light as in Earth orbits) making cooling easier. An interferometer design would also improve resolution. A not-widely advertised feature of the JWST is that, due to the same Rayleigh limits, its far infrared modes have dramatically lower resolution than its near infrared camera. A problem with a 6 meter mirror, less of a problem with a kilometer mirror.

I remembered European Southern Observatory employing optical interferometry on the ground. And indeed it does: https://www.eso.org/public/news/eso1905/
Cool to see Clifford Stoll mentioned there, he was also the one detecting one of the first international state-sponsored hacking attacks on the US and wrote a book about it, The Cuckoo's Egg.
Trump famously tweeted images from an Iranian launch facility that had exploded. They were incredibly revealing of US satellite capabilities, even though that was probably not as zoomed-in as they could go.

https://www.nbcnews.com/politics/national-security/oval-offi...

In 2022 Trump declassified this satellite picture showing amazing resolution of current generation: https://media.npr.org/assets/img/2019/09/05/ap_1924315303447...
By declassified, you mean accidently tweeted a cell phone picture of the image printed out.

Which is his right, just wanted to add context.

It wasn't on accident.
Depends on what you call the accident. However, we will only know after November 5th.
No no, he is actually correct and I misspoke. He definitely tweeted on purpose (haha) but did he intend to declassify the image or just didn't realize?
According to NBC[1], attempts were made to explain the ramifications to him. At that point, he knew he was declassifying the photo and knew he was revealing what his experts told him shouldn't be revealed. He simply didn't care.

[1] https://www.nbcnews.com/politics/national-security/oval-offi...

Yes he quite possibly unintentionally revealed US spy satellite capabilities with an otherwise purposeful tweet. I say the not out of niceness to give him the benefit of the doubt, but because he's probably too stupid to understand the implications of what he was doing.
That looks about as high-resolution as Google Maps to me. I’m sure the government can do much, much better, but this isn’t a good showcase.
Apples to oranges comparison there.

A great deal of Google Map imagery over urban areas is from relatively low level aerial survey aircraft that run lines over cities in summer.

The resolution is better and stitched together often provides a better bang for the buck than satellite imagery.

That said, Trump's image may have been from a sat or from a high altitude spy plane - they'd have ballpark optics but the aircraft would be closer in and more maneuverable .. I'd personally discount whatever Trump had to say about the source and want to hear from a third party military reconnaissance expert.

Yeah, I’m referring to Google Maps satellite imagery, not the super-saturated and detailed urban area coverage. I mean, check out the satellite view here [1]. It’s not perfect, but you can make out building-sized objects and cars just as well as you can in the Trump image.

[1]: https://maps.app.goo.gl/Fic93Bhf8X8CA5De6

You example from airbus maxar technologies (https://www.airbus.com/en/space/earth-observation/satellite-...) is close but falls short of the detail in the Trump tweet - cross bracing on the gantry and radio tower is a giveaway.