Originally published here: Planet Nine scaled one in 250 million by tato_713 - Thingiverse
This is a representation of how it could be in size the hypothetical planet beyond Neptune, proposed by many astronomers, nicknamed "Planet Nine". It is just a sphere made with Microsoft 3D Builder and scaled in the same scale of other planets like the Earth and Neptune or Uranus; assuming a radius of 2.5 Earth radius. Remember that this planet has no direct evidence of its existence, and it remains as speculative.
Since the discovery of Neptune, it's being speculated that a giant object may be orbiting beyond it, because of anomalies on the planet's orbit. The hypothetical planet could do this deviations by the influence of its mass. Pluto seemed to fill this definition, but was soon noticed that its mass is too low. Since then, the disturbances in the orbit of Neptune were regarded as errors. The discovery of Trans-Neptunian objects with high eccentricity and a large perihelion like Sedna takes to the idea that these objects were scattered by a bigger body. These objects, named Sednoids, and the extreme TNOs (with similar extreme orbital parameters) share approximate the same direction of their eccentricities. Batygin and Brown proposed that an orbiting object of several times the mass of the Earth with the eccentricity pointing in the opposite direction of that of the sednoids could solve this problem. The WISE sky survey has ruled out the presence of anything bigger than Neptune beyond its orbit and within the Solar System boundaries, and an Earth mass object is not heavy enough to fit the requirement these perturbations, so it is estimated that the Planet Nine is between 5 and 10 Earth masses, and between 2 and 4 times its radius. Other causes could explain the "evidence" for the Planet Nine hypothesis, like a past close passing star, or observational bias.
Type: Planet.
Orbit: Sun.
Orbital period: 10000 to 20000 yr
Composition: Rocky, gaseous, or something between them.
Model scale: 1:2.5x108 (13cm) 1:5x108 (6cm)
![]() |
Earth in light blue, Planet Nine hypothetical size in white, and Neptune in dark blue |
The author marked this model as their own original creation. Imported from Thingiverse.