Discovery and exploration of the Solar System Domenico Cassini later discovered four more moons of Saturn and the Cassini division in Saturn's rings. Edmond Halley realised in 1705 that repeated sightings of a comet were recording the same object, returning regularly once every 75–76 years. This was the first evidence that anything other than the planets orbited the Sun. Around this time (1704), the term "Solar System" first appeared in English. In 1781, William Herschel was looking for binary stars in the constellation of Taurus when he observed what he thought was a new comet. Its orbit revealed that it was a new planet, Uranus, the first
Minor planet more are discovered each month. The Minor Planet Center has documented over 188 million observations and 757,626 minor planets, of which 516,386 have orbits known well enough to be assigned permanent official numbers. Of these, 21,264 have official names. , the lowest-numbered unnamed minor planet is , and the highest-numbered named minor planet is 495759 Jandesselberger. There are various broad minor-planet populations: All astronomical bodies in the Solar System need a distinct designation. The naming of minor planets runs through a three-step process. First, a provisional designation is given upon discovery—because the object still may turn out to be a