Mons Huygens Moon further north, which was visited by Apollo 15. The tallest mountain known in the Solar System is in Rheasilvia crater on the asteroid Vesta, which contains a central mound that rises high; Olympus Mons on Mars is nearly the same height, at high. In comparison, Mount Everest rises to altitude above sea level (asl), but is only (base-to-peak) (btp). Africa's Mount Kilimanjaro is about altitude above sea level to the Uhuru peak; also 4.6 km base-to-peak. America's Denali, also known as "Mount McKinley", has a base-to-peak of . The Franco-Italian "Mont Blanc/Monte Bianco" is in altitude above sea level,
Fictional planets of the Solar System Fictional planets of the Solar System The fictional portrayal of our Solar System has often included planets, moons, and other celestial objects which do not actually exist in reality. Some of these objects were, at one time, seriously considered as hypothetical planets which were either thought to have been observed, or were hypothesized in order to explain certain celestial phenomena. Often such objects continued to be used in literature long after the hypotheses upon which they were based had been abandoned. Other non-existent Solar System objects used in fiction have been proposed or hypothesized by persons with no scientific standing,