Rings of Neptune narrow, dusty ringlets and even fainter broad dusty rings. The rings of Neptune, like those of Uranus, are thought to be relatively young; their age is probably significantly less than that of the Solar System. Also, like those of Uranus, Neptune's rings probably resulted from the collisional fragmentation of onetime inner moons. Such events create moonlet belts, which act as the sources of dust for the rings. In this respect the rings of Neptune are similar to faint dusty bands observed by "Voyager 2" between the main rings of Uranus. The innermost ring of Neptune is called the "Galle ring"
Fictional planets of the Solar System while yet others are purely fictional and were never intended as serious hypotheses about the structure of the Solar System. Vulcan was a hypothetical planet supposed to revolve around the Sun inside the orbit of Mercury, invoked to explain certain irregularities in Mercury's orbit. The planet was proposed as a hypothesis in 1859, and abandoned not later than 1915. The name "Vulcan" has been used for various other fictional planets, in and out of the Solar System, that do not correspond to the hypothetical planet Vulcan. The planet Vulcan in the "Star Trek" franchise, for instance, is specified as orbiting