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What a tweet tells us about spy satellites [video]

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

#21

Post by alkonaut »

vinaypai wrote: post #14
pcunite wrote: post #7

I hold the understanding that its possible to view a license plate from space. I suggest you keep to that view in mind as well.

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 probably not worth trying.

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

#23

Post by drivebycomment »

benburleson wrote: post #19
pcunite wrote: post #7

I hold the understanding that its possible to view a license plate from space. I suggest you keep to that view in mind as well.

This is anecdotal, and no idea how real it is, but my dad flew reconnaissance for the USAF in the 70s and claimed to have the capability to read license plates way back then from very high altitude (no idea what qualified as very high altitude, but assumed they were not easily detected from the ground).

Let's do some napkin math. A quick websearch suggests spy sats orbit around 200-800km, while U2 flies at 20km.

Let's say you can use the same camera system on both. Then 10cm resolution at 200km orbit means 1cm at 20km, which would be enough to read a license plate.

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

#25

Post by tempguy9999 »

throwawaywego wrote: post #16
pcunite wrote: post #7

I hold the understanding that its possible to view a license plate from space. I suggest you keep to that view in mind as well.

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?

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

#26

Post by nexuist »

makomk wrote: post #9
runlevel1 wrote: post #3

How it was tracked back to USA 224: https://github.com/cbassa/satellite_analysis/blob/master/nah...

The really astounding part of all this is that hobbyists have been monitoring the exact orbits of all the US spy satellites for years. They know exactly where they're overhead and when. That kind of capability used to be something that only a handful of states had, and now people just do it from their homes and post it to the internet.

"Who watches the watchers?"

Civilian space nerds!

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

#28

Post by inetsee »

Two things I got from the video:

1) The videos of the launches are scary, especially the launches with the "A" rockets, and the fireball surrounding the rocket at the beginning of the launch.

2) It's a shame the patch with the Klingon text never made it out into the wild.

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

#29

Post by withinboredom »

hirundo wrote: 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.

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

#30

Post by smudgymcscmudge »

nexuist wrote: post #26
makomk wrote: post #9

Earlier quoted context omitted.

The really astounding part of all this is that hobbyists have been monitoring the exact orbits of all the US spy satellites for years. They know exactly where they're overhead and when. That kind of capability used to be something that only a handful of states had, and now people just do it from their homes and post it to the internet.

"Who watches the watchers?" Civilian space nerds!

“but who watched them?”

CIA, and we’ve gone full circle.

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