A newly discovered object orbiting far beyond Neptune has its closest approach to the Sun pointed in the opposite direction from every other known body like it, weakening one of the central ...

The shape of a planet's orbit is one of its fundamental properties, along with its size and distance from its host star. Earth has a nearly circular orbit, but some planets outside our solar system, ...

Studying the orbits of thousands of exoplanets shows that large planets tend to have elliptical orbits, while smaller planets tend to have more circular orbits. This split coincides with several other ...