Point-Ahead Aiming for Deep-Space Laser Links

Optical (laser) communication packs vastly more bandwidth than radio, but its narrow beam turns a light-time-of-flight problem into a real aiming problem: across interplanetary distances the receiver moves a significant fraction of a beamwidth while the photons are still in transit. This simulator computes the point-ahead angle from range, wavelength, aperture and relative transverse speed, launches a photon pulse toward either the receiver's current apparent position or its correctly led future position, and reports whether the pulse actually lands inside the diffraction-limited footprint — the same targeting problem solved onboard NASA's Deep Space Optical Communications demonstration.