Live data from Hacker News

What a tweet tells us about spy satellites [video]

youtube.com

31–40 of 81 posts

Re: What a tweet tells us about spy satellites [video]

#31

Earlier quoted context omitted.

I'm of the understanding that this was not a single image, but a composite image, taking by different satellites, planes, and/or drones. The US could have build test facilities in their deserts, have a 3-D model available for proper reconstruction, and then learn to stitch and skew back all imagery into a single composite image. There may even be some "filling in" or "sharpening" of pixels or textures that could not…

Why do you believe it's a composite image? > the license plate was not observed in the moment the main photo was taken I believe there's a limit on resolution of a space satellite. If you're suggesting the traffic cam reads the plate, how are you going to connect the coloured blob that is the car with an image taken by a traffic cam at a different time in a country that doesn't give you access to its traffic cams?

> 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 later date. Inpainting, upscaling, de-oldifying, automatic coloring, 3D modeling, composition (see black hole photo process) etc. have become common usage in the ML community, and so I have reason to assume these techniques are also used to enhance and improve the resolution and unobserved guesstimates of satellite imagery.

> how are you going to connect the coloured blob that is the car with an image taken by a traffic cam at a different time in a country that doesn't give you access to its traffic cams?

Install road-side pointing camera's inside rented housing / contracted freedom fighter homes? Hack the traffic cams?

Didn't the NSA track mobiles in foreign countries by installing similar beacons / hacking sensors in bigger cities? That would theoretically allow them to view through the car roof and "see" who is in the backseat.

> The spy agency is said to be tracking the movements of “at least hundreds of millions of devices” in what amounts to a staggeringly powerful surveillance tool. It means the NSA can, through mobile phones, track individuals anywhere they travel – including into private homes – or retrace previously traveled journeys.

> The NSA provided some input into the report, with one senior collection manager, granted permission to speak to the newspaper, admitting the agency is “getting vast volumes” of location data from around the planet by tapping into cables that connect mobile networks globally.

> According to the Post, the NSA is applying sophisticated mathematical techniques to map cell phone owners’ relationships, overlapping their patterns of movement with thousands or millions of other users who cross their paths.

Re: What a tweet tells us about spy satellites [video]

#32

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…

You don’t need multiple to get improvement in one dimension: it’s moving.

For something that will hold very still, you can wait for the next pass and synthesize.

Re: What a tweet tells us about spy satellites [video]

#33

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…

> * 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 :)

Re: What a tweet tells us about spy satellites [video]

#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 factored it in?

My guess is you would assume that this capability exists.

If I wanted to be really good, I would assume 10x this capability exists.

Re: What a tweet tells us about spy satellites [video]

#35

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 :)

Annoyed? Sure. Surprised? Only the naive would be.

Re: What a tweet tells us about spy satellites [video]

#37

Earlier quoted context omitted.

Why do you believe it's a composite image? > the license plate was not observed in the moment the main photo was taken I believe there's a limit on resolution of a space satellite. If you're suggesting the traffic cam reads the plate, how are you going to connect the coloured blob that is the car with an image taken by a traffic cam at a different time in a country that doesn't give you access to its traffic cams?

> 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 :)

Re: What a tweet tells us about spy satellites [video]

#38

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 :)

But we followed the making of hubble long before it launched. Why would anyone believe such a silly rumor when the development of the telescope was in the open?

Re: What a tweet tells us about spy satellites [video]

#39
post #4

The good news is that there is a redacted area in the image, so Trump probably didn't just snap and post ... evidence of some limit to the impulsiveness of the commander in chief.

The top left would have been information about the picture. Time/Date and source.

That's also what I'd guess, tho kinda funny how censoring that out turned out to be kinda pointless.

Re: What a tweet tells us about spy satellites [video]

#40
post #38

Earlier quoted context omitted.

> * 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 :)

But we followed the making of hubble long before it launched. Why would anyone believe such a silly rumor when the development of the telescope was in the open?

What makes it a rumor? In the video Scott states that the “cost saving measure” of reducing the target mirror diameter down to 2.4m was to use the same manufacturing as these exact spy satellites.
Post reply on HN