What a tweet tells us about spy satellites [video]

Post by throwawaywego » Sun, Sep 01, 2019, 4:56 PM UTC

tempguy9999 wrote: post #37

throwawaywego wrote: post #31

Earlier quoted context omitted.

> Why do you believe it's a composite image? Because it is common to reconstruct a signal by taking multiple measurements, instead of a single sample. The field of compressed sensing broke ground on effective sampling. If (some) error is random noise, then you can remove this by majority vote. It is ineffective not to re-use that high-resolution secret drone fly-over footage, when composing satellite imagery at a lat…

Maybe mixed terminology, to me a composite pic is one where sections or entireties of several pics have been arranged to make a larger or more detailed one. What you desrcibe is different, but ISWYM. > Install road-side pointing camera's inside rented housing / contracted freedom fighter homes? Hack the traffic cams? perhaps, sounds a bit james bondish though :)

Post by velox_io » Sun, Sep 01, 2019, 5:14 PM UTC

iamshs wrote: post #2

That image is absolutely bonkers, the more I look at it, the more I admire the satellite's creators. Also, the analysis around the image is fantastic. The data and methods that they used to calculate the height of the satellite, timing of picture etc. it is a treat to see for someone sitting and seeing this unfold on the sides. I remembered this article [1], of Indian Anti-Satellite Test, India claimed satellite was…

Post by billh » Sun, Sep 01, 2019, 5:39 PM UTC

BurningFrog wrote: post #33

alkonaut wrote: post #21

Earlier quoted context omitted.

There are certainly no 20-30m telescopes in space (Also, imagine how annoyed astronomers would be if they found out the biggest most advanced space telescope in history was in space and pointing down...). I do wonder what would be possible to resolve using multiple 2.4m scopes to create a larger synthetic aperture? Resolving text on a license plate which would be at a very oblique angle (so more atmosphere) is probab…

> * imagine how annoyed astronomers would be if they found out the biggest most advanced space telescope in history was in space and pointing down* Well, rumor is that Hubble was just a repurposed spy telescope, so astronomers probably should be annoyed :)

Post by Rebelgecko » Sun, Sep 01, 2019, 5:44 PM UTC

alkonaut wrote: post #21

vinaypai wrote: post #14

Earlier quoted context omitted.

The resolution of this satellite is about 5-7 cm per pixel which is about the limit of what's possible with the 2.4m mirror it uses. You'd need a mirror at least 10x as large to read license plates, and that's if they were pointing upward.

There are certainly no 20-30m telescopes in space (Also, imagine how annoyed astronomers would be if they found out the biggest most advanced space telescope in history was in space and pointing down...). I do wonder what would be possible to resolve using multiple 2.4m scopes to create a larger synthetic aperture? Resolving text on a license plate which would be at a very oblique angle (so more atmosphere) is probab…

Post by gruez » Sun, Sep 01, 2019, 5:54 PM UTC

fareesh wrote: post #34

From what I understand, it was already well known that the USA could take satellite photos of things, except not at the level of quality/detail as the one shown in this image. Is that a distinction without a difference? I suppose in theory now that this information is out there regarding capabilities, you know this for sure, but would you have guessed the capability is not there if you were making a decision that fac…