Outer planets Outer planets The outer planets are those planets in the Solar System beyond the asteroid belt, and hence refers to the gas giants and ice giants, which are in order of their distance from the Sun: The outer planets all have ring systems, although all but Saturn's are faint when viewed from Earth. Another aspect common to the gas giants is their many natural satellites (moons), two of which are larger than the planet Mercury (Jupiter's Ganymede and Saturn's Titan). That pair and Io, Callisto, Europa, and Triton, are larger than Pluto and Eris. This region of space is also
Max Planck Institute for Solar System Research MPS is organised in three departments: In addition, since 2002 there is also an International Max Planck Research School. Subjects of research at the Institute are the various objects within the solar system. A major area of study concerns the Sun, its atmosphere, the interplanetary medium as influenced by the solar wind, as well as the impact of solar particles and radiation on the planets. The second area of research involves the interiors, surfaces, atmospheres, ionospheres, and magnetospheres of the planets and their moons, as well as of comets and asteroids. A further essential part of the activities at the