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There's a few highly suspect details in the way the author got the 34-35 degree estimate. Maybe he was just really lucky and the errors cancelled out, but don'

There's a few highly suspect details in the way the author got the 34-35 degree estimate. Maybe he was just really lucky and the errors cancelled out, but don't count on using his method to produce similar results. Polaris is about .8 degrees away from the celestial North pole, so using it alone can give a reading off by .8 degrees, and the orientation in the photo is actually nearing the worst case. The horizon doesn't appear in the photo. I have done celestial navigation strictly as a hobby for fun, and using a sextant without a visible horizon results in a few degrees of error at best. And that's with the benefit of the sensation of gravity helping you estimate. It is theoretically possible to estimate the horizon using the man made parallel horizontal lines in the image, but the author doesn't give any indication he did that. Additionally, the author used the angle measurement tool in Stellarium to measure the distance to another ambiguous horizon. This is incredibly odd, as just clicking on Polaris in Stellarium will tell you its elevation. But even more odd, is he would have had to explicitly set his latitude in the app in order to get that screenshot.

microsoftdoes 4y ago
Interesting. So do you think the author had inside information on the location?
- gmiller123456 4y ago
  I'm not going to speculate on what someone did or didn't know, let's give him the benefit of the doubt and just say he was really lucky. My main point was just don't expect similar results if you try it yourself.
  - samstave 4y ago
    Yeah, but when did he know it? (god i hope you get this joke)
    - timoteostewart 4y ago
      What’s more, there’s an 18-minute gap on the tape!
- mhh__ 4y ago
  It was publicly accessible, or so I've read at least
- gateorade 4y ago
  The fact that the b21 is being built at plant 42 in Palmdale has been public info for literal years.
  - texasbigdata 4y ago
    And they had the press release there lmao
- relaxing 4y ago
  The author notes in the writeup that an educated guess could be made with public details about who the manufacturer was.
  - tapland 4y ago
    Edward’s is a classic and would be a top hit to re-visit on maps with any kind of buildings visible for a quick confirmation.
gmiller123456 4y ago
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.
- gmiller123456 4y ago
  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 the top that you can just use the top edge of the photo as a reference). If you start with a photo the same size I did (4096x2731), you can just crop the photo from top down to where you think the horizon is, then look at the size of the resulting image, multiply the vertical pixels by .0161, and post the answer below.
  - comboy 4y ago
    Wide angle lens distortion?
    - gmiller123456 4y ago
      I thought lens distortion would be a problem too, but there's really not much distortion. The lines on the buildings and runway are all pretty straight, even near the corners of the photo where distortion would be at it's maximum. I'm willing to bet the photographer has a lot of experience photographic large planes and knew what steps to take to avoid it coming out all contorted.
jaxomlotus 4y ago
If I were a betting man I would assume he started this exercise with the final assumed location in mind, and worked backwards from there to show how it could have been done.
- deleted 4y ago
  [deleted]
- baxtr 4y ago
  That's actually what he was implying in his last tweet: > The press conference to reveal the aircraft was held here last week so we can confirm the location. A guess likely would have landed someone in the same location but fun anyway to star match. I'm sure this entire process could be done with just stars and no google maps as well
  - barelysapient 4y ago
    Aka, “parallel reconstruction”
whywhywouldyou 4y ago
I'm sure you're correct, as the whole thing reads like "look how smart I am". 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. 2. Mentions things like them not scrubbing the EXIF data was a "mistake". How could it be a mistake if this was public information? 3. Says at the end "(this data is all public now)". Making it sound like he made the data public through his top notch sleuthing. It should read "this data was all public a week prior to my analysis".
- sumofproducts 4y ago
  > as if government spy satellites operate on the same schedule with the same priorities as publicly known satellites. This bit, at least, is more or less the case. Even if you spend some fuel to alter your orbit and throw people off for a bit, you can't do anything major over the course of a few hours without sci-fi engines.
- mschuster91 4y ago
  > 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 this was public information? Because even what otherwise should be public domain under US copyright rules can still be censored for national security reasons - precisely to avoid OSINT research like this. What some random Twitter hobby astronomy researcher can do in their free time with basic tools, Russian and Chinese secret services can do as well. Another fine example just how important attention to detail is with maintaining operational security.
  - rob74 4y ago
    > 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. Of course, but I think they would refrain from publishing that information? Unless they want to make sure that "they know that we know"...

microsoftdoes 4y ago

Interesting. So do you think the author had inside information on the location?

gmiller123456 4y ago
I'm not going to speculate on what someone did or didn't know, let's give him the benefit of the doubt and just say he was really lucky. My main point was just don't expect similar results if you try it yourself.
- samstave 4y ago
  Yeah, but when did he know it? (god i hope you get this joke)
  - timoteostewart 4y ago
    What’s more, there’s an 18-minute gap on the tape!
mhh__ 4y ago
It was publicly accessible, or so I've read at least
gateorade 4y ago
The fact that the b21 is being built at plant 42 in Palmdale has been public info for literal years.
- texasbigdata 4y ago
  And they had the press release there lmao
relaxing 4y ago
The author notes in the writeup that an educated guess could be made with public details about who the manufacturer was.
- tapland 4y ago
  Edward’s is a classic and would be a top hit to re-visit on maps with any kind of buildings visible for a quick confirmation.

gmiller123456 4y ago

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.

gmiller123456 4y ago
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 the top that you can just use the top edge of the photo as a reference). If you start with a photo the same size I did (4096x2731), you can just crop the photo from top down to where you think the horizon is, then look at the size of the resulting image, multiply the vertical pixels by .0161, and post the answer below.
- comboy 4y ago
  Wide angle lens distortion?
  - gmiller123456 4y ago
    I thought lens distortion would be a problem too, but there's really not much distortion. The lines on the buildings and runway are all pretty straight, even near the corners of the photo where distortion would be at it's maximum. I'm willing to bet the photographer has a lot of experience photographic large planes and knew what steps to take to avoid it coming out all contorted.

jaxomlotus 4y ago

If I were a betting man I would assume he started this exercise with the final assumed location in mind, and worked backwards from there to show how it could have been done.

deleted 4y ago
[deleted]
baxtr 4y ago
That's actually what he was implying in his last tweet: > The press conference to reveal the aircraft was held here last week so we can confirm the location. A guess likely would have landed someone in the same location but fun anyway to star match. I'm sure this entire process could be done with just stars and no google maps as well
- barelysapient 4y ago
  Aka, “parallel reconstruction”

whywhywouldyou 4y ago

I'm sure you're correct, as the whole thing reads like "look how smart I am". 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. 2. Mentions things like them not scrubbing the EXIF data was a "mistake". How could it be a mistake if this was public information? 3. Says at the end "(this data is all public now)". Making it sound like he made the data public through his top notch sleuthing. It should read "this data was all public a week prior to my analysis".

sumofproducts 4y ago
> as if government spy satellites operate on the same schedule with the same priorities as publicly known satellites. This bit, at least, is more or less the case. Even if you spend some fuel to alter your orbit and throw people off for a bit, you can't do anything major over the course of a few hours without sci-fi engines.
mschuster91 4y ago
> 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 this was public information? Because even what otherwise should be public domain under US copyright rules can still be censored for national security reasons - precisely to avoid OSINT research like this. What some random Twitter hobby astronomy researcher can do in their free time with basic tools, Russian and Chinese secret services can do as well. Another fine example just how important attention to detail is with maintaining operational security.
- rob74 4y ago
  > 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. Of course, but I think they would refrain from publishing that information? Unless they want to make sure that "they know that we know"...