Poles of astronomical bodies pole. This definition means that an object's direction of rotation may be negative (retrograde rotation) — in other words, it rotates clockwise when viewed from above its north pole, rather than the "normal" counterclockwise direction exhibited by Earth's north pole. Venus rotates in the opposite direction to the other planets, and Uranus has been knocked on its side and rotates almost perpendicular to the rest of the Solar System. The ecliptic remains within 3° of the invariable plane over five million years, but is now inclined about 23.44° to Earth's celestial equator used for the coordinates of poles. This large
Solar System in fiction and that Mars could hardly support any macroscopic life forms on its surface, much less an advanced civilization. In the 1980s it was shown that the surfaces of Jupiter's moons were just as hostile to life. More recent fiction focused on the Solar System has thus tended to address its exploration for purposes such as terraforming, the engineering of planets for human habitation, than the possibility of any existing life. The following works or series use multiple planets and other locations within the Solar System as their primary settings: Solar System in fiction The Solar System and its various bodies