Ganymede (moon) moon Titan, which was previously thought to have been bigger. The grooved terrain was also seen. In 1995, the "Galileo" spacecraft entered orbit around Jupiter and between 1996 and 2000 made six close flybys to explore Ganymede. These flybys are denoted G1, G2, G7, G8, G28 and G29. During the closest flyby—G2—"Galileo" passed just 264 km from the surface of Ganymede. During a G1 flyby in 1996, the Ganymedian magnetic field was discovered, while the discovery of the ocean was announced in 2001. "Galileo" transmitted a large number of spectral images and discovered several non-ice compounds on the surface of
Fictional planets of the Solar System fragments of a single planet was gradually abandoned over the course of the middle decades of the 20th century in favor of the conclusion that no planet had ever accreted in the region of the asteroid belt in the first place. In fiction, various other names were given to the same or similar concepts. Fictional planets in our Solar System beyond the orbit of Neptune have been employed many times as settings or references in science fiction. Following the general reception of Pluto as the ninth planet of the Solar System in 1930, a hypothetical additional planet was sometimes called