Potentially dumb question - how do people even find these things???
Stealth bomber in flight on Google Maps
151–160 of 390 posts
Re: Stealth bomber in flight on Google Maps
#152Earlier quoted context omitted.
I wonder how low it is, found the shadow of it close by 39.02468482732915, -93.6023120071418 https://www.google.com/maps/place/39%C2%B001'28.9%22N+93%C2%...
nice catch! I think the altitude could be calculated roughly if we knew the the day of the year the photo was taken.
okay so i'm not sure how accurate any of this is since it's overlaying sun angles over a photo that is very likely not taken from a 90deg overhead angle to the bomber... and the scale of the image may be distorted a little...
I discovered on google earth that the image was taken May 16th.
I used this site http://shadowcalculator.eu/#/lat/39.02397754136213/lng/-93.6... to draw a fence around the bomber and defined the "structure" to be an arbitrarily tall height until the sun angle lined up.
Then I lowered the height until the sun angle touched the location of the shadow and I came to an altitude of 1100ft / 335.28m (rough height of the "structure")
Re: Stealth bomber in flight on Google Maps
#153Earlier quoted context omitted.
It actually works out to be pretty close. A satellite flying ~17k mph at 250 miles altitude would largely have the same angular displacement from the ground as a plane moving 400 mph at 31,000 feet. Most satellites fly in an easterly direction, so the question would ultimately be what the inclination of the orbit is relative to the direction of flight.
That's super interesting! I love this discussion. Would the satellite be that low though? 250 miles (400km) is still going to experience significant atmospheric drag. Fine for a cheap mass deployment like Starlink, but I'd expect an imaging satellite to be set up for a longer mission duration. Then again maybe the cost of additional mass for station-keeping is worth it for the imaging quality.
You can find a list of satellites here: https://www.ucsusa.org/resources/satellite-database
According to the image on Google maps it was taken by Maxar. Maxar appears to have a few satellites, looks like 5 in geostationary orbit (~35,700km), 3 at about 400km and 1 at about 500km.
Re: Stealth bomber in flight on Google Maps
#154Earlier quoted context omitted.
These are pushbroom linear sensors stacked up in the focal plane. The spectral channels are physically separated by larger distance than neighboring pixels in a Bayer grid. There is a time delay between each channel sweeping over the same location that gets corrected when the final imagery is aligned. The moving plane at altitude violates assumption of a static scene and exposes the scanning behavior.
For anyone wondering about what a pushboom sensor is - http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.72.... Basically a 1D sensor that acquires a 2D image because the camera itself is moving. In this case, I'd imagine that there are 3 such sensors for RGB.
FWIW, depending on the satellite (this one is probably WorldView 3), there usually more like ~6-7 channels in the visible.
It makes for easier top-of-atmosphere correction, and can be useful for things other than pretty pictures.
Re: Stealth bomber in flight on Google Maps
#155Earlier quoted context omitted.
Interesting. A search for those gradients could help find all fast moving objects in the satellite images.
Now that’s an interesting idea. Anyone care to spin this up?
Is there a way to subscribe to comments? I'd love to see the result of this idea but am not savvy enough to spin it up myself very easily
Re: Stealth bomber in flight on Google Maps
#156Earlier quoted context omitted.
Seems like you're right - there's one parked on (indeed) Whiteman Air Force Base right here https://goo.gl/maps/x8738SicBvtSPqmR6
that's awesome.. I thought Army bases are masked on maps.
There's really no point. A few high sensitivity assets are lower resolution, but any state actor that wants very high resolution shots of military facilities already has it and on a quicker update cadence than google maps allows.
Re: Stealth bomber in flight on Google Maps
#157The measured wingspan (using the Google Maps distance measure tool) is around 200 feet whereas the measured wingspan of a B-2 on the ground at nearby Whiteman AFB is the nominal 172 feet, so its altitude AGL is roughly 14% of the altitude of the camera plane that took the photo.
A small roll of the place at the time the photo was taken could also explain this difference.
Re: Stealth bomber in flight on Google Maps
#158Interesting 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.
Is there a dataset with all the close-up satellite images somewhere?
Re: Stealth bomber in flight on Google Maps
#159Earlier quoted context omitted.
These are pushbroom linear sensors stacked up in the focal plane. The spectral channels are physically separated by larger distance than neighboring pixels in a Bayer grid. There is a time delay between each channel sweeping over the same location that gets corrected when the final imagery is aligned. The moving plane at altitude violates assumption of a static scene and exposes the scanning behavior.
I think modern satellites have matrix sensors
It depends on the satellite. Weather satellites in GEO do because they aren't moving relative to the surface and they have time constraints for scanning the full earth disc. Higher resolution imaging satellites use linear sensors. However, they use TDI imaging which at a low level makes them superficially like an area array with limited vertical resolution but the light collection is still fundamentally different.
Re: Stealth bomber in flight on Google Maps
#160Interesting in itself there is this, but we never manage to find similar gems for UFOs.