Astronomers have spent years searching for a possible hidden giant planet far beyond Neptune. Unusual orbits among distant Kuiper Belt objects have fueled the Planet Nine theory, but recent ...

Planet 9 sits at the edge of scientific imagination, promising either an epic expansion of the Solar System or a lesson in how easily patterns can mislead us. As new data arrive and old assumptions ...

For most of human history, our view of “close to the Sun” was defined by the orbit of Mercury, with its 88-day orbit and barren, baking surface. But from the moment we started discovering exoplanets, ...

The solar system is a dynamic place, and objects located 180° from a planet don’t stay that far from the planet for long. The reason is the differences in their orbits. Orbits come in all shapes and ...