Planet Nine — the undiscovered planet at the edge of the solar system that was predicted by the work of Caltech’s Konstantin Batygin and Mike Brown in January 2016 — appears to be responsible for the unusual tilt of the Sun. The large and distant planet may be adding a wobble to the solar system, giving the appearance that the Sun is tilted slightly.
In the race towards the discovery of Planet Nine, scientists from around the world strive to calculate its orbit using the tracks left by the small bodies that move well beyond Neptune. Now, astronomers from Spain and Cambridge University have confirmed that the orbits of the six extreme trans-Neptunian objects that served as a reference to announce the existence of Planet Nine are not as stable as originally thought.
By combining data from two space observatories, astronomers have revealed something surprising: a 955-mile-wide dwarf planet named 2007 OR10 is significantly larger than previously thought. Although its 547-year-long elliptical orbit brings it nearly as close to the Sun as Neptune, 2007 OR10 is currently twice as far from the Sun as Pluto.