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## Friday, October 13, 2017

### Deconstructed - Auguste Piccard: “It seemed a flat disk with upturned edge”

Deconstructed - Auguste Piccard: “It seemed a flat disk with upturned edge”

Is it possible he means it looked like an upturned disk?  As in, you see a bit of horizon curvature?

 Stratobowl image from 1935

The human eye has a wide field of view so you see a bit more of the Horizon Circle than most images and thus more curvature, all else being equal. One reason for this is that this is NOT the "curvature of the Earth" -- this is the curvature of the Horizon Sagitta viewed nearly on edge.  This is a mistake I constantly see people making.  So it's not a circle of 3959 miles diameter that curved downward, but an OVAL that you are in the middle of with, in this case, a 300 mile radius and viewed on edge at a 4.8° angle -- and this oval curves 360° around YOU.

As to why it looks flat, it's because the terrain is far away and the curvature is fairly slight and you're looking down on it.  We just cannot see the geometry under these conditions.  You can't even see the giant hills and valley's of the Dakota's in Steven and Anderson's image.

 Google Earth view from 14mi

The elevation variation across just the Black Hills area is about 3700 feet and you can't see ANY of it.  It "looks flat" because it should.  But where the features are located and how far we can see are the unmistakable markings of a Globe.

How far back is this speaker tilted?

How much are these two images of this building tilted?

If you cannot measure these tilts how do you think you can see the shape in patterned ground from 100's of miles away to see a small change in the terrain that is Earth's curvature?