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Cliché - Yes - the stars are rendered on a 50-60-sided polygonal 'sphere'. If you look carefully, you can see the stars are at slightly different angles depending on which polygon they're being projected onto. Sometimes you can actually make out the boundaries of the polygons (each one is a trapezoid of two triangles), especially when a star happens to fall on the boundary and get 'bent'. They appear a little slanted/distorted.
That's probably not entirely true. The skybox used in ED is a 6 sided cube.
I happened to encounter a bug with my old R9-290X and CV1, with which after some game time, about 20 jumps, the texture would get blocky with psychedelic colors starting from the bottom of the screen inside the ship, and with more jumps, it get progressively worse extending up to the top of the screen, and eventually the skybox gets blocky. This happened to show me clearly that the skybox is a 6-sided cube. Well, I did "stick" my head out of the cockpit to take a peek (climb up my chair).
Unfortunately, the attachments on ED forum does not directly accept PNG or BMP-like files. And I am too lazy to post the screenshot online. Moreover, to fully "see" that it's a 6 sided cube, you really have to look around (too narrow the field of view), even though I have a screenshot of a corner of the skybox which "sort of" let you see it's a cube, but it's not entirely self-evident.
A 6-sided skybox has its advantages over a skydome. One of them being the parallel projection is simple -- for Z=0 plane projection, just set Z=0, done. Projection to a skydome is not difficult at all, but it does involve floating point calculation, which is an order of magnitude computationally more expensive than setting Z = 0 or Z = 50'.
But I do agree that the skybox is about 50' from the PoV; I mean, it didn't look farther than the Douglas Fir tree in my yard. However, I suck at distance estimation, so take that with a large grain of salt. Assuming the about 50' is true, then, everything within the skybox must have been scaled down accordingly (not necessarily linearly scaled down though), because by its spec. the nose of my Fed. Corvette would have been longer than 50' extruding outside of the skybox if it were rendered to scale.