Planet Nine Planet Nine Planet Nine is a hypothetical planet in the outer region of the Solar System. Its gravity could explain the unlikely clustering of orbits for a group of extreme trans-Neptunian objects (eTNOs) that orbit beyond Neptune with average distances greater than 250 AU. These eTNOs tend to have their points of closest approach to the Sun clustered in one direction, and many of their orbits have a similar tilt. This evidence suggests that the gravity from a large undiscovered object is influencing the orbits of the most distant known Solar System objects. This undiscovered super-Earth-sized planet would have an
Max Planck Institute for Solar System Research Research offers the PhD programme "International Max-Planck Research School (IMPRS) for Solar System Science" together with the University of Göttingen. The Solar System School offers a three-year course of study emphasizing actual research. The curriculum covers the entire area of the solar system from small bodies to the planets and the Sun. The goal is a broad, interdisciplinary, and solid scientific education, extended with courses in numerical physics, space technology, project management, scientific writing, and presentation techniques. There are always about 50 graduate students studying at the Solar System School. Two thirds are from abroad from over 30 different countries.