Aperture Orbit. A crisp six-point aster (Astra = star, the asterisk that annotates every image) sits dead-center inside two thin rings that read at once as a camera-lens aperture and a celestial orbit — optics meeting the cosmos, the emitted rays of radiology. The cyan core carries the accent while the ink rings hold structure, so the mark stays monochrome-safe. At favicon scale the inner ring drops to a single bold aperture ring plus a slightly enlarged star, keeping the eye clean at 16px where two hairlines would muddy.