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Stealth bomber in flight on Google Maps

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Re: Stealth bomber in flight on Google Maps

#301

Post by coderenegade »

jcims wrote: post #296
iamtedd wrote: post #262

Earlier quoted context omitted.

What an awful picture of the NRO Director. Surely they have plenty of experience in photography in less than ideal conditions. So why have this photo as the first thing I can see on their website?

It’s so bad it seems unlikely it isn’t a joke. I mean look at their mission patches: https://en.wikipedia.org/wiki/List_of_NRO_launches

The gorilla holding the US flag is my favourite. And it might just be me, but the Nemesis badge has to be a sphincter, right? It reminds me of the Greendale flag in community.

Re: Stealth bomber in flight on Google Maps

#302

Post by PostOnce »

a2800276 wrote: post #211
PostOnce wrote: post #166

Earlier quoted context omitted.

In case anyone else is reading and thinking of that predicament, it needn't be a showstopper. You have a couple of options: You can do it the old way, and pay someone to convert it into the new way (I know a mechanical engineer who either sketches things or does 2D on a computer, and pays someone else to 3D it) which can then be sent to the client or manufacturer or whatever. Or, if you're doing the whole product to…

Not sure if the Air Force will buy bomber seats from the back of a truck of some guy who designs them with paper and pencil.

If not, the defense contractor will subcontract to you and mark it up 4000% :)

Also, the government generally has policies that some % of things have to come from small businesses, sometimes they'll hire you just in order to check a box, I'd guess.

Nevertheless, if you can design an airplane seat, there are other customers than the air force.

Lots of niche machines are made by 3 or 4 people and sold for hundreds of thousands of dollars per unit, to farms, to factories, to anyone in business. Consumers will argue with you for a week over a $10 purchase, but people buying things to make money with won't bat an eye at $10,000.

There's a great big world out there and every hurdle doesn't have to be jumped, you can just walk around it half the time.

Re: Stealth bomber in flight on Google Maps

#303

Post by cyberlurker »

xvector wrote: post #284
FearlessNebula wrote: post #275

Earlier quoted context omitted.

Could he not take a class or an apprenticeship for CAD?

Learning things becomes much harder when you are older. Our brains are physically less receptive to the process of learning.

I don’t think this is true. I think responsibilities pile up and/or the need to learn more is less. The physical ability to learn is probably hardly impacted.

Re: Stealth bomber in flight on Google Maps

#304

Post by lmc »

jerry1979 wrote: post #37
MontyCarloHall wrote: post #9

Interesting how the three separate R/G/B images are taken independently a few ~seconds~ milliseconds apart, with a different color filter placed over the image sensor. I assume this is to maximize resolution, since no Bayer interpolation [0] is needed to demosaic the output of a traditional image sensor that integrates the color filters onto the sensor pixels themselves. As these satellites are not intended to photog…

Interesting. A search for those gradients could help find all fast moving objects in the satellite images.

A guy did it with trucks for Sentinel-2 data. https://www.esa.int/Applications/Observing_the_Earth/Monitor...

Re: Stealth bomber in flight on Google Maps

#305

Post by Gustomaximus »

mynameismon wrote: post #66

Archived before it's taken down: https://archive.ph/E8xih (don't spam click it, it is already extremely slow to load, the last thing we want to do is DDOS archive.ph)

Taken down by the government?

Id be surprised if the military is bothered by this. I have nothing to do with military etc but assume China/Russia have high res satellites taking photos/scans across airbases on a regular basis and have much better quality to investigate the technology than a google sat image.

Re: Stealth bomber in flight on Google Maps

#306

Post by dalmo3 »

bpye wrote: post #300
oppositelock wrote: post #298

Earlier quoted context omitted.

The B2 bomber photo isn't from a push boom sensor, because it would be distorted since it's moving relative to the camera. This would manifest itself as a shear along the motion vector . There is no shear in this photo, only spectral bands. I've spent a number of years doing image orthorectification, and satellite imagery post-processing, then also worked on Google Earth and Google Maps, so I can tell you precisely w…

Shame we don't know what the delay between spectra is, would be fun to work out how fast the plane is traveling.

I've seen larger aberrations from satellite captures of planes. But I've no idea how to estimate height or speed by that.

Re: Stealth bomber in flight on Google Maps

#308

Post by oppositelock »

dalmo3 wrote: post #306
bpye wrote: post #300

Earlier quoted context omitted.

Shame we don't know what the delay between spectra is, would be fun to work out how fast the plane is traveling.

I've seen larger aberrations from satellite captures of planes. But I've no idea how to estimate height or speed by that.

You can get height if you can find the shadow, and find the time that the photo was taken, because at any given time and date, you can compute sun position, and you know the precise lat/lng of the shadow. The shadow would need to be in the same photo, though. (actually, it's a bit to the northwest, just found it).

If you can find a vertical structure, like an antenna mast, you can measure shadow length and direction and if you know the height of the antenna, you have enough information for some trigonometry.

Speed is harder. You'd need to know the difference between exposures.

Re: Stealth bomber in flight on Google Maps

#309

Post by oppositelock »

oppositelock wrote: post #308
dalmo3 wrote: post #306

Earlier quoted context omitted.

I've seen larger aberrations from satellite captures of planes. But I've no idea how to estimate height or speed by that.

You can get height if you can find the shadow, and find the time that the photo was taken, because at any given time and date, you can compute sun position, and you know the precise lat/lng of the shadow. The shadow would need to be in the same photo, though. (actually, it's a bit to the northwest, just found it). If you can find a vertical structure, like an antenna mast, you can measure shadow length and direction…

Aha! Here we go. Here's a telephone pole: https://earth.google.com/web/search/39.0303298,-93.58495/@39...

We know that telephone poles stick about 32 feet from the ground. Measuring the shadow in Google Earth above, it's about 20 feet. Now, it's a simple ratio.

Using Earth, I measured the distance from the plane to its shadow at about 2430 feet, that would put it at 3,900ft, which is surprisingly low, but I don't know the height of that pole for sure. It's the right ballpark, though.

Re: Stealth bomber in flight on Google Maps

#310

Post by ehsankia »

fullstop wrote: post #199
willis936 wrote: post #113

Earlier quoted context omitted.

The google maps scale shows the plane as being pretty close to that length as well. I think the satellite is high enough up that altitude scaling for aircraft is going to be minimal. I see about a 10 foot separation between colors. Velocity = distance / time 400 mph is 587 fps. 10 / 587 = 17 ms

Do they actually use satellites for their "satellite" view? I always assumed that it was done by aircraft.

It's definitely a mix, depending on the area and the resolution. For urban places where they have 3D views and higher resolution, it's definitely planes. For a random place like this at low resolution, it's satellites.
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