Comment by gmiller123456 | Hacker News Reader

Comment by gmiller123456 | Hacker News Reader

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.

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".

> 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.

> 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.

> 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"...

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.

1. What orbit sphere level do spy sats sit at?

(I worked with many sat engs from Loral and another quiet facility called Lokheed (Also you shouls look into BALL ((the actual Mason Jar company - and see how many spy sats they make)))

-

Anyway, I think that DEFCON needs to break this shit open....

Read all the lines, then read all the ones in-betweeen....

Serious.

> I'm sure you're correct, as the whole thing reads like "look how smart I am".

It's been that way for a long time. The whole "UFO movement" had it's flames fanned by agents of foreign power who literally salivate at how many useful idiots will do the work their analysts would have done.

Some officer in the Russian equivalent of the NRO is probably gonna take that post and run with it.

> as if government spy satellites operate on the same schedule with the same priorities as publicly known satellites.

It's basically impossible to hide things in orbit. Hobbyists have been able to track the Misty spy satellite that has an inflatable cone to mask its optical signature. The major powers all operate space tracking radars that can spot anything up there bigger than about a baseball.

Also nearly all optical imaging sats are in sun synchronous orbits because it maximizes power generation vs solar panel size as well allows comparison of multiple days images with the same shadow angles.

> How could it be a mistake if this was public information?

Well they scrubbed the data from the website so that's a pretty clear indication it was a mistake. You're oversimplifying this into a binary thing, whereas a lot of security is more of the form "this isn't foolproof but there's no need for us to make it this easy."

>How could it be a mistake if this was public information?

Not to pile on, but the government releases info by mistake all the time. Even simple things like doing a crappy job redacting court filings. It's just people doing this stuff, and people make mistakes all.the.time.

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.

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

Aka, “parallel reconstruction”

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 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.

Wide angle lens distortion?

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.

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

It was publicly accessible, or so I've read at least

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.

Yeah, but when did he know it?

(god i hope you get this joke)

What’s more, there’s an 18-minute gap on the tape!

The fact that the b21 is being built at plant 42 in Palmdale has been public info for literal years.

And they had the press release there lmao

The author notes in the writeup that an educated guess could be made with public details about who the manufacturer was.

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.

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