KH-12 Kennan Keyhole Secret Military Spy Satellite Photos | Hacker News Reader

KH-12 Kennan Keyhole Secret Military Spy Satellite Photos

spacesafetymagazine.com

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Even more striking is the fact this was (likely) taken by hand[1], and with just a 10-inch aperture telescope!

[1] http://www.spacesafetymagazine.com/space-debris/astrophotogr...

website seems down, but google cache here: http://webcache.googleusercontent.com/search?q=cache:9jrWlnp...

If only we had a KH-12 on the ground we could use to take pictures of KH-12's overhead...

In a manner of speaking, we already do have two KH-12's on the ground.

The two telescope optical assemblies that were donated by NRO to NASA (https://en.wikipedia.org/wiki/2012_National_Reconnaissance_O...) are generally believed to be from the FIA, an ambitious satellite series that was originally planned to succeed the KH-11 line. But the optical side of the FIA had huge cost and schedule over-runs, and the simplified KH-12 was adopted instead.

But note, the FIA telescopes were optimized for wide-area coverage, not for high resolution, so they wouldn't be ideal. ;-)

You have much bigger telescopes than the KH-12 on the ground, it won't help you much tho, magnification doesn't work with telescopes as you expect, and you can always stack lenses to get more magnification but it won't matter.

Large telescopes have a much bigger field of view that's pretty much it. Even angular resolution wont matter that much at these distances, satellites that look like a blob on a prosumer telescope will look like a blob even if taken from a full scale observatory.

That's not really correct. Most large telescopes have a small FoV for starters (couple of arcminutes at best). Bigger telescopes gather more light and can thus see fainter objects.

The biggest limit to angular resolution (beyond some rather small diameter optic) is atmospheric seeing. This prohibits you from resolving anything smaller than 0.5-2 arcseconds (depending on the site conditions) regardless of the optic used.

But there are to compensate for atmospheric seeing: Adaptive optics (AO) and Lucky Imaging (you don't integrate for a long time, but only take very short exposures and once in a while you get lucky and the atmosphere doesn't distort the image much and you get a very high resolution image). AO is what's usually available at very large telescopes, while Lucky Imaging is usually done on medium to small telescopes. And for LI gathering more light (and therefore a bigger optic) does help.

So yes.. with a bigger telescope and a fast(er) camera you would probably be able to take a better picture (and moving to a place with good seeing would certainly help as well).

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