Stephen P. Synnott, a Voyager project navigator at the Jet Propulsion Laboratory, who discovered a 15th moon of Jupiter last spring, has done it again. He discovered a 16th Jovian satellite while searching through photographs taken last year by Voyager spacecraft whose missions were to confirm the discovery of a 14th satellite. Synnott's newest discovery, tentatively numbered 1979 J3, is about 340 km in diameter. It circles the planet once in 7 hours, 4 minutes, 30 seconds, with an uncertainty of 3 to 5 seconds. This latest discovery came from the same process in which he found the 15th satellite in March 1980. Synnott believed at that time that he had confirmed the earlier sighting of the 14th satellite because they had similar orbits and sizes.