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Re:Stealth bomber in flight on Google Maps by ericbarrett on Monday December 20, 2021 @01:23PM (#29628042)
My napkin calculations are that the three channels are ~10ms apart, given the bomber is 69 feet nose-to-tail* and an assumption of 400 mph velocity.

* http://www.dept.aoe.vt.edu/~mason/Mason_f/B2Spr09.pdf

Re:Stealth bomber in flight on Google Maps by willis936 on Monday December 20, 2021 @02:21PM (#29628907)
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

Re:Stealth bomber in flight on Google Maps by fullstop on Monday December 20, 2021 @04:14PM (#29630359)
Do they actually use satellites for their "satellite" view? I always assumed that it was done by aircraft.
Re:Stealth bomber in flight on Google Maps by Cd00d on Monday December 20, 2021 @04:45PM (#29630713)
Depends on the needed resolution. You can cover a lot more earth, far more cheaply with a satellite with several meter wide pixels.

When I used to work in remote sensing I remember that Bing Maps had a very distinct resolution transition from spacecraft to aircraft. Aircraft coverage maps were a small subset of the total earth land area, but most US towns had some coverage at that time (~2012).

As you zoomed in, you could tell when Bing switched capture methods because the aircraft cameras were clearly off-nadir, and you'd see off-angle perception differences.

Re:Stealth bomber in flight on Google Maps by reportingsjr on Monday December 20, 2021 @05:57PM (#29631599)
They only use aircraft around larger urban areas. Satellite imagery is used for rural areas. You can see the resolution difference by seeing how far you can zoom in.

If you zoom in on a road near the pinned location for this post, and then go to, say, downtown kansas city, and zoom in you'll see a pretty significant difference.

Re:Stealth bomber in flight on Google Maps by willis936 on Monday December 20, 2021 @04:28PM (#29630534)
Flying a plane around the planet sounds a lot more expensive financially and thermodynamically than just beaming down images from an object constantly falling into the views you want to see.
Re:Stealth bomber in flight on Google Maps by dzhiurgis on Monday December 20, 2021 @04:38PM (#29630651)
You are only interested in urban areas which is less than 1% of total earth surface
Re:Stealth bomber in flight on Google Maps by omoikane on Monday December 20, 2021 @04:49PM (#29630763)
It's also the case that often there are more legal regulations around aerial imagery compared to satellite imagery.
Re:Stealth bomber in flight on Google Maps by fullstop on Monday December 20, 2021 @04:30PM (#29630556)
I looked it up. There are some satellite images, but a lot of it is done by aircraft.
Re:Stealth bomber in flight on Google Maps by op00to on Monday December 20, 2021 @04:57PM (#29630869)
Or you could just strap a camera to a few commercial airliners and have full coverage.
Re:Stealth bomber in flight on Google Maps by dylan604 on Monday December 20, 2021 @05:47PM (#29631480)
You'd only have full coverage of the jet routes. They don't just fly willy nilly across the globe.
Re:Stealth bomber in flight on Google Maps by ehsankia on Monday December 20, 2021 @09:22PM (#29633080)
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.
Re:Stealth bomber in flight on Google Maps by 0xQSL on Monday December 20, 2021 @03:52PM (#29630134)
One might be able to calibrate this by using cars in the area close to the shot [1]. Assuming most cars are driving at the speed limit

[1] https://www.google.com/maps/place/38%C2%B059'37.1%22N+93%C2%...

Re:Stealth bomber in flight on Google Maps by myself248 on Monday December 20, 2021 @04:18PM (#29630419)
The cars aren't flying at altitude though. They're farther from the satellite.
Re:Stealth bomber in flight on Google Maps by contravariant on Monday December 20, 2021 @04:28PM (#29630531)
How low are these satellites? I wouldn't expect the altitude of a plane to be any significant proportion of the altitude of a satellite.
Re:Stealth bomber in flight on Google Maps by natosaichek on Monday December 20, 2021 @05:31PM (#29631266)
The satellites are probably greater than 400 km altitude, or so, while the plane is probably 10 km. The plane is in the same rough order of magnitude as really tall mountains, which the satellite is presumably designed to compensate for, so I agree with your general assessment.
Re:Stealth bomber in flight on Google Maps by tech_timc on Monday December 20, 2021 @06:13PM (#29631734)
The Google Maps image copyright is for Maxar, which means the collector is likely Worldview-3, which is at nominally 614 km above the Earth.

https://earth.esa.int/eogateway/missions/worldview-3

Re:Stealth bomber in flight on Google Maps by willis936 on Monday December 20, 2021 @07:35PM (#29632355)
The shadow is 750 m away and the sun is about 15 degrees off noon, so the B2 altitude is roughly 3 km. Cousin comment says the satellite altitude is 614 km, so I wouldn't expect parallax effects to be dominant. This is also evidenced by the fact that both the plane and ground are in focus and the plane is measured to be 70 feet long in google maps, which is what it is specified to be in reality.
Re:Stealth bomber in flight on Google Maps by exabrial on Monday December 20, 2021 @05:33PM (#29631297)
That bomber is also likely quite low, since it's based out of an air force base in that area.
Re:Stealth bomber in flight on Google Maps by myself248 on Monday December 20, 2021 @05:44PM (#29631447)
Sure, but when the word "calibrate" comes up, you want to account for even the not-very-significant factors.
Re:Stealth bomber in flight on Google Maps by ATsch on Monday December 20, 2021 @01:29PM (#29628142)
I would assume that the plane or satellite moving affects this too, it's presumably being corrected but there might be some parallax.
Re:Stealth bomber in flight on Google Maps by ericbarrett on Monday December 20, 2021 @01:35PM (#29628223)
You're absolutely correct, but as the aircraft is much closer to the ground than the imaging satellite I disregarded it. Spherical cows and all that :) I'm sure a military analyst would do the calculations!
Re:Stealth bomber in flight on Google Maps by jcims on Monday December 20, 2021 @01:51PM (#29628457)
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.
Re:Stealth bomber in flight on Google Maps by chrissnell on Monday December 20, 2021 @02:28PM (#29629001)
I think this plane is flying much lower and slower. The B2s are based at Whiteman AFB, which is about 25 miles south of this photograph. The prevailing winds in this part of the country are from the south, so I suspect that it is about to turn onto the final leg of its approach for a landing to the south. I’d guess that it’s no more than 8-10K’ and traveling at a 2-300 knots max.
Re:Stealth bomber in flight on Google Maps by t0mas88 on Monday December 20, 2021 @04:15PM (#29630381)
Definitely. Rule of thumb in a jet is to slow down if you're closer than 3x the altitude. So at 8k feet you want to be at least 24 nautical miles (27 normal miles) away or if closer you want to be slowing down (or descending). If you don't slow down before you're going to have to do so in the descend and typical jets can't really slow down much in that.
Re:Stealth bomber in flight on Google Maps by dylan604 on Monday December 20, 2021 @05:53PM (#29631554)
I asked google maps to get directions from there to Whiteman AFB. Unfortunately, flight directions were not available.
Re:Stealth bomber in flight on Google Maps by bigiain on Monday December 20, 2021 @06:14PM (#29631747)
And you are now on a list...
Re:Stealth bomber in flight on Google Maps by dylan604 on Monday December 20, 2021 @06:49PM (#29632035)
I've been on a list for so so long now that this one is just another. No big deal.
Re:Stealth bomber in flight on Google Maps by Terry_Roll on Monday December 20, 2021 @07:15PM (#29632203)
Hey welcome to the list, I've been on it since Primary School believe it or not, but only found out a few years ago!
Re:Stealth bomber in flight on Google Maps by Sporktacular on Tuesday December 21, 2021 @07:03AM (#29636547)
How did you find out?
Re:Stealth bomber in flight on Google Maps by bragr on Monday December 20, 2021 @02:13PM (#29628797)
Most imaging satellites are in sun synchronous orbits so likely in this case moving north or south and slightly retrograde e.g. west.

I'd bet orbital motion is negligible here because the distortion seems to the eye to be entirely in the direction of the plane's apparent motion vector and I don't see any significant skew to that.

Re:Stealth bomber in flight on Google Maps by ericbarrett on Monday December 20, 2021 @02:07PM (#29628703)
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.
Re:Stealth bomber in flight on Google Maps by penagwin on Monday December 20, 2021 @03:16PM (#29629712)
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 by Koshkin on Monday December 20, 2021 @02:11PM (#29628758)
Re:Stealth bomber in flight on Google Maps by jcims on Monday December 20, 2021 @06:36PM (#29631919)
Looks like you nailed it! ctrl+f pushbroom in the thread if you haven’t seen it.
Re:Stealth bomber in flight on Google Maps by matbatt38 on Thursday December 23, 2021 @07:02PM (#29668137)
Well no the speed of the satellite is irrelevant there, the background is not getting distorded at all
Re:Stealth bomber in flight on Google Maps by the-dude on Monday December 20, 2021 @02:09PM (#29628739)
Isn't the speed of the sat irrelevant as it should correct for this anyways for all images it takes?
Re:Stealth bomber in flight on Google Maps by xmonkee on Monday December 20, 2021 @02:22PM (#29628929)
yeah, exactly
Re:Stealth bomber in flight on Google Maps by joan_kode on Monday December 20, 2021 @02:05PM (#29628671)
Interesting, I would have made the opposite assumption ("the satellite is moving so much faster than everything else, we can estimate the interval from the satellite's speed alone). It seems both speeds might have a similar impact, as per sibling comment.
Re:Stealth bomber in flight on Google Maps by okl on Monday December 20, 2021 @01:39PM (#29628273)
Can you calculate the time of day from the shadow's length as well?

https://www.google.com/maps/place/39%C2%B001'18.5%22N+93%C2%...