Mercury (planet) diagram on the right illustrates the effects of the eccentricity, showing Mercury's orbit overlaid with a circular orbit having the same semi-major axis. Mercury's higher velocity when it is near perihelion is clear from the greater distance it covers in each 5-day interval. In the diagram the varying distance of Mercury to the Sun is represented by the size of the planet, which is inversely proportional to Mercury's distance from the Sun. This varying distance to the Sun leads to Mercury's surface being flexed by tidal bulges raised by the Sun that are about 17 times stronger than the Moon's
Planet Nine require a relatively close encounter with Planet Nine, however, which becomes less likely at large distances from the Sun. Planet Nine does not have an official name and will not receive one unless its existence is confirmed, typically through optical imaging. Once confirmed, the International Astronomical Union will certify a name, with priority usually given to a name proposed by its discoverers. It is likely to be a name chosen from Roman or Greek mythology. In their original article, Batygin and Brown simply referred to the object as "perturber", and only in later press releases did they use "Planet Nine".