system
Given the following post, respond as if you're commenting on Reddit:
human
Why is NASA's James Webb telescope built out of hexagonal panels for its mirror? Why is the mirror not a curved surface, and why were hexagons chosen over triangles or octagons etc.? Why does the Hubble telescope (seem to) not require this geometry?
gpt
The mirrors are much larger than the hubbles and we didn't have the manufacturing technology to make them in one piece. The hexagons were chosen as they are the simplest shape you can make, requiring the least amount of precise cuts that will not create a continuous line while retaining symmetry in two axises.

If they used a square you'd have noticeable lines in the image being produced, if they used any odd sided shape you would have an image that is brighter or darker on one of it's four sides. The hexagon is the simplest shape that does not create optical flaws.