Rings of Neptune
In 1989 the unmanned spacecraft Voyager 2 flew by Neptune. Voyager 2 sent back pictures that gave most of the information that scientists now have about the rings of Neptune. The pictures also help scientists to know why the rings looked incomplete. Not only did the pictures give a closer view, but they also showed the rings in a way that cannot ever be seen from earth. From earth the rings are always seen with the light of the sun shining towards them. When the spacecraft went past the planet, it took pictures with the sun shining behind the rings, as well. Big particles in the rings looked dark against the sunlight, but all tiny dust particles (microscopic dust) shone brightly when the sun was behind it. This allowed the scientists to work out what the rings were made of, and how all the particles were arranged.