Satellite photo of 2 planes in close proximity- Real or artifact?

Take a look at this satellite photo:

Is this an actual photo of two Mexicana jets about 800 feet apart or an artifact of how Google stitches together photos? My first thought was that it couldn’t be real, but the fact that the two planes seem offset from a single plane’s flight path, made me think twice.

The jet(s) are pretty close to O’hare, so (to me) that make it seem even more unlikely that it would be 2 planes.

Definitely an artefact: it’s the same plane.

Those are almost certainly aerial photos, not satellite images. The fact that the planes flight paths appear to be offset can be explained by theparallax effect.

Also, why don’t the planes appear to have shadows?

OK, let me clarify. I have no irrefutable evidence that it’s the same plane.

But I have blown it up to the maximum resolution, and overlayed the two planes in Photoshop, and they’re exactly the same size, which means they were both at the same altitude when the picture/s was/were taken.

I don’t want to sound like a moon conspiracy theorist, but the shadows cast by the antennae on the roof of the plane are at exactly the same angle when overlayed, although the plane to the east is rotated anticlockwise by about 1 degree - but without rotating the shadow.

ETA:

Whistleblowers, man.

The umbral shadow of an airplane only appears when it is below ~2000-10,000’ AGL depending on the size of the airplane, and sun angle. The penumbra is seldom visible at all, as it’s edges are quite indistinct. At about half the above height, the umbra becomes indistinct enough that the shadow is not really airplane shaped.

Interestingly, from the aircraft, areas around the aircraft’s shadow appear brighter. This effect continues even after shadow vanishes at higher altitude, causing a “bright spot” where the shadow would otherwise be. This is due to the fact that nothing on the ground (weeds, buildings, etc) has a visible shadow at that location. The size of the “bright spot” increases with farther altitude, the edges becoming less distinct, until it too becomes unnoticeable.

This effect is only observable from the line defined by the sun and the aircraft…other observers will see a bright spot where thier own shadow would be.

I don’t know the answer but according to the scale they’re about 1000 ft apart, and separation requirements at the same altitude are measured in miles. It’s a crisis if separation measured in minutes is as low as 1. A separation of 1000 ft is around, what, 2 seconds of separation at 400 MPH? No doubt that would cause quite an incident. The trailing pilot would also have a visual on the lead plane way before this would happen. Not to mention the controllers jumping up and down about it when they were a less than a couple of miles apart.

So I don’t know the facts but there are controls in place to keep something like this from happening.

I’ve always assumed, as Santo Rugger says, that the high-resolution images on Google Maps are from aircraft rather than satellites. But it seems slightly odd that an aerial photo plane would be permitted to fly directly over a passenger jet. Is that normal practice?

If you zoom out a bit, you will notice a rather large airport around a mile away, in the opposite direction the airplane is flying. I suspect it just took off, and was at a very low altitude.

Yes, I know the plane is very low, but it still seems a bit… odd to permit flying directly over a take-off path. Any light-aircraft pilots care to chip in with the regulations on this?

Perhaps it has something to do with the photo and map-making process. Maybe it’s two photos of the same plane at two slightly different time intervals or perhaps even two photos of two different planes, coincidentally of the same make and airline, but the photos are “stitched” together to make the Google Map.

As suggested in the OP :smack:

I can’t see the picture at work, but I can comment on this in general.

Depending on the airport, the wind, and the active runways, sometimes the clearest path is right over the top. I got my license near Seattle. At the time, Sea-Tac airport had two runways, running north-south. Assuming the wind is from the south, you’ll have planes from every direction converging and queueing north of the airport to land in an orderly sequence. And departing planes will be taking off to the south, and dispersing to wherever they’re going. If you’re in a light plane to the west of the airport, and want to go east, the safest route is right over the top of the airport. All the traffic will be beneath you. You damn well better be in contact with the airport approach control, though.

Those conrollers know what they’re doing.

Retired aerial mapping pilot here.

Is not satellite photo but normal aerial mapping shot.

Yes, stitching gave you the double aircraft image.

Quite normal to map over , under, around normal airline traffic. Needs to be a lot of advance planning, coordination etc.

I have mapped DFW several times. Once, doing the Trinity River from Ft Worth to Dallas we even had our own dedicated controller. Took weeks to set up and several trips to to the tower and RADAR room and duplicate maps etc…

I had to have a safety observer who only looked for other aircraft in our co-pilot seat, etc.

I also mapped the McMurry building in OKC the next day. Had to meet with the feds at an OKC airport first. We did it at their request.

Have done all around O’Hare and many others.

Many strange effects found in aerial photos. If you have access to the original negatives, you can usually figure out how they happened.

In the OP’s link, you can see in part of the field below, the line that shows up running left - right between the aircraft where the two photos join.

The actual negatives for those pictures were taken at 10,000 feet or less and probably lower. Looks like a Wild camera instead of a ** Ziess** as that effect is more likely with their sideways negative advance instead of instead of the fore - aft advance that Ziess uses.

Due to sun angle and the images being near the edge of the negatives, the shadows very easily may not be visible.

That’s not a problem at all. Commercial aircraft are commonly routed directly over airports. Let’s say the imaged plane (I can’t see it because Google Maps’ satellite view is not working for me right now) is at 5000 ft, and the photographing plane is at 40,000 ft. What would be the issue with that?

Useless anecdote: I toyed with the idea of taking an airtraffic controllers aptitude test in the early 90’s.

Some of the “tips” mentioned in taking those (in test quides I checked out in the library) was that air traffic controllers are allowed to route aircraft to no closer than 1000 feet of each other.

I suppose that that distance can vary in the more congested areas (where a single controller may be responsible for more aircraft, and has less time to devote to each individual aircraft).

But the lit area (of the northern shadowed (by the vertical stabilzer) horizontal stabilizer) of the western image is larger than the lit area on the eastern image. The plane was probably banking left when the two images were made, although the angle of shadow of the antenna (that you noticed) would not have changed and maybe the length of shadow was too small to notice whereas the lit areas on the northern H.S. are large enough to notice at max resolution.

Dang, I hope I explained this correctly.

It seems to me that the likely scenario (which builds slightly on the suggestions made here so far) is that the mapping plane is traveling from north to south snapping pictures at a pretty quick rate. It takes the first picture and the plane is in the position on the left, then a moment later snaps another picture. The lower plane has obviously moved southeast in the moment, but the parallax caused by the movement of the mapping plane shifts the image of the plane to the north, making its path look funny.

As for the shadows, look at the shadows of the trees. The sun is low enough that the shadows of the planes, if they were even visible, would be pretty far away from the planes themselves, possibly into the next row of pictures. When the mapper comes by to take the next row of pictures, the shadow is obviously not there anymore.

BTW, unless we’re looking at different lines, I’m not sure I agree with this:

The line I’m looking at runs right into a tree on the east end and then there’s a diagonal line going northeast from there. I think it’s a path worn by people walking. It’s not very straight and it’s also not perfectly east-west, which I’d expect the stitch marks to be. And finally, there’s a group of people walking on it. :slight_smile:

I’m thinking it’s the same plane’s picture taken, as mentioned above, in two different pictures.

If you blow up the photo you can see the exhaust from the engines blurring the ground below from both planes. While copying the plane and pasting it where it shows in the picture is possible, it would be difficult to copy exhaust and the ground below it and make that look right.

As GusNSpot says, it is the same airplane in two photos taken at different moments. It can be explained very easily. Imagine the camera was traveling to NE. The first picture is taken. The camera has now moved to NE and the plane appears to have moved forward due to its own motion and also sideways with respect to the background due to the camera’s motion.

Knowing the speed of the airplane we could know the time difference between the photos and also calculate the altitude of the camera from the parallax.

1000 feet is normal vertical separation (actually, 500 feet is normal separation at low altitudes between VFR and IFR aircraft.) 1000 feet is very close for horizontal separation though. Horizontal separation is miles and minutes rather than 1000s of feet and seconds.