Phobos 2 Phobos 2 Phobos 2 was the last space probe designed by the Soviet Union. It was designed to explore the moons of Mars, Phobos and Deimos. It was launched on 12 July 1988, and entered orbit on 29 January 1989. "Phobos 2" operated nominally throughout its cruise and Mars orbital insertion phases on 29 January 1989, gathering data on the Sun, interplanetary medium, Mars, and Phobos. "Phobos 2" investigated Mars surface and atmosphere and returned 37 images of Phobos with a resolution of up to 40 meters. Shortly before the final phase of the mission, during which the spacecraft was
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