Diffraction Spikes: A Segmented Telescope's Point Spread Function

Every image a space telescope takes carries the fingerprint of its own mirror. This simulator builds a real 19-segment hexagonal primary mirror in the style of the James Webb Space Telescope, lets you add secondary-mirror support struts, and computes a genuine 2D Fourier transform of that aperture to render the telescope's actual point spread function — the star image you would really see, spikes and all. Adjust the mirror diameter and observing wavelength to watch the Airy core and Rayleigh resolution scale, switch between a 3-strut tripod and a 4-strut "+" mount to see six spikes become eight, and change the strut width to trade spike length for spike brightness, all backed by the same Fraunhofer diffraction math astronomers use to plan real observations.