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Finding the B-21's hangar location from the stars in its press image

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Re: Finding the B-21's hangar location from the stars in its press image

#201

Post by Sporktacular »

burntwater wrote: post #138
Sporktacular wrote: post #126

Earlier quoted context omitted.

So it's manipulative. Like a sensational headline that buries the mundanity at the end. Lead with "this is already publicly known" so people can make an informed choice about where to direct their attention.

If the point of the article/twitter thread was to reveal the location of the hanger, as if that was previously a secret, then yes perhaps the title is misleading. But that's not the point of the article. The point of the article was to reveal the location of the hanger using the stars and other metadata , and to explain how that was done. The journey was the story, not the destination.

"as if that was previously a secret"

And that's where the disagreement is. It implied a secret by the nature of the object, enough so that the fact it wasn't needed to be clarified - but at the end. You only publicly reveal something once, and this already had been.

But then, those aren't his words and it's implicit so this is a grey area and not a huge deal. But I still think leaving the clarification to the end was deliberate.

Re: Finding the B-21's hangar location from the stars in its press image

#202

Post by comboy »

gmiller123456 wrote: post #181
gmiller123456 wrote: post #151

Earlier quoted context omitted.

I extended many of the assumed parallel lines in the photo, and they all tend to converge just below and to the right of the nose of the plane. And using the known distance between two of the stars to estimate the degrees per pixel, I get a margin of error of about 4 degrees vertically estimating where the horizon is.

For what it's worth, I measured the pixels between Kochab and Pherkad and got .0161 degress per pixel. Then measured from Polaris to my visual guestimate of where the horizon should be and got 34.14 deg, about half a degree off of the real location. I'd be interested to see what others get. For those not familiar with the stars, Polaris is just a few pixels from the top edge, nearly dead center (it's close enough to…

Wide angle lens distortion?

Re: Finding the B-21's hangar location from the stars in its press image

#203

Post by 4gotunameagain »

protastus wrote: post #143
4gotunameagain wrote: post #136

Earlier quoted context omitted.

If the "DC value of the sky" could be removed with a simple high pass filter, then there would be no need of doing anything else. The positions of the stars in the sky would be known, and techniques like the one in the article would apply. I have been working fine so far in startrackers for spacecraft without your tutorial in signal processing, but thanks for the offer

> If the "DC value of the sky" could be removed with a simple high pass filter, then there would be no need of doing anything else. The positions of the stars in the sky would be known, and techniques like the one in the article would apply. This doesn't make any sense. Even if one could estimate ground truth DC, removing it would leave noise at every other frequency bin. But this is beside the point. Your questionin…

you were the one suggesting "removing the DC value of the sky with high pass filtering". anyway I'm done. have a nice day.

Re: Finding the B-21's hangar location from the stars in its press image

#204

Post by 082349872349872 »

throwaway1492 wrote: post #155
jbverschoor wrote: post #135

Earlier quoted context omitted.

Do they’re trying to scare Russian with an airplane that can only be taxied around? I wonder if it’s made out of proper material and not just some clay concept

Russia military is a pitiful shell of the former Soviet glory. Putin’s actions in Ukraine have effectively demilitarized them. They squandered their inheritance of Soviet equipment like an 18 year old in Vegas. Their nuclear force is a giant question mark. Their three legs of the nuclear triad are quite shaky. In the event of a MAD exchange; Their boomers won’t get a missile off due to the fast attacks that keep them…

Speaking of ICBM's, I'm sure they use more sophisticated targeting now, but in the early days they'd astrogate for any necessary mid-course corrections.

(Cannot remember if I saw this procedure on a film narrated by von Braun himself, but I doubt it; I think I saw him in a Disney)

Re: Finding the B-21's hangar location from the stars in its press image

#207

Post by nradov »

samstave wrote: post #198
mschuster91 wrote: post #191

Earlier quoted context omitted.

> 1. Extraneous details about satellites not being overhead at night -- as if government spy satellites operate on the same schedule with the same priorities as publicly known satellites. You can bet that the US, China and Russia know about at least the orbital data of all satellites that the other nations put up. > 2. Mentions things like them not scrubbing the EXIF data was a "mistake". How could it be a mistake if…

We will never learn of satellite war.... we will never hear about attack sat drones that take out other sats but it happens regularly... think of the plane that was in orbit as 3 years, which was the Jimmy Carter of space (I hope you know that ref) ((if you dont, then you dont know shit))

That's paranoid nonsense. Attack drones don't regularly take out other countries' satellites. There is no way to hide such activity in orbit and it would be obvious to everyone, including amateur civilian observed.

Here's the real situation. All of the superpowers have some level of kinetic anti-satellite weapons capability and have conducted a few isolated tests against their own satellites. The X-37B drone spaceplane may have some anti-satellite role but has never been used operationally in that capacity.

Re: Finding the B-21's hangar location from the stars in its press image

#208

Post by Kiboneu »

insane_dreamer wrote: post #47
lmm wrote: post #44

Earlier quoted context omitted.

Exactly, whereas stars shown in the image are just data, you don't need the exif data to see them.

But the time the photo was taken was extracted from the exif which is what OP was referring to stripping

The lesson here isn’t to strip exif data, though. It’s to identify information that can be connected to anything to infer metadata that you want to keep hidden.

If you always wipe exif data, and don’t investigate your pictures, then you will eventually neglect some combination of data points someone could use to infer richer context.

Re: Finding the B-21's hangar location from the stars in its press image

#209

Post by nradov »

082349872349872 wrote: post #204
throwaway1492 wrote: post #155

Earlier quoted context omitted.

Russia military is a pitiful shell of the former Soviet glory. Putin’s actions in Ukraine have effectively demilitarized them. They squandered their inheritance of Soviet equipment like an 18 year old in Vegas. Their nuclear force is a giant question mark. Their three legs of the nuclear triad are quite shaky. In the event of a MAD exchange; Their boomers won’t get a missile off due to the fast attacks that keep them…

Speaking of ICBM's, I'm sure they use more sophisticated targeting now, but in the early days they'd astrogate for any necessary mid-course corrections. (Cannot remember if I saw this procedure on a film narrated by von Braun himself, but I doubt it; I think I saw him in a Disney)

ICBMs still use a mix of stellar and inertial navigation. They can't rely on satellite navigation because in a major conflict those may be destroyed or jammed.

Some modern ICBMs might also have some limited terminal guidance capacity but there's not much public information on that subject.

Re: Finding the B-21's hangar location from the stars in its press image

#210

Post by sumtechguy »

partiallypro wrote: post #163

One of my favorite internet happenings is when 4Chan (I think it was 4Chan) used stars and airplane data to get Shia LaBeouf's flag location and steal it. Not because of the political message, but because it was just entertaining and impressive in general. I think it ended up being in Tennessee somewhere. In any case, this wasn't exactly a secret, journalists were invited (though they had their cellphones confiscated…

That went on for a few months. I think he ended up sticking it on a blank wall in an airbnb. They still figured it out. Because he decided to go out and have a few drinks. Also because info is wildly leaky. It is interesting how leaky info is and how little it takes to narrow it down. Advertisers use that non intuitive fact to do browser fingerprinting.
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