Far beyond Neptune, astronomers have finally confirmed a compact clump of icy worlds hiding inside the Kuiper Belt, a feature ...

Fresh mapping of the outer solar system has revealed a previously unseen pattern in the Kuiper Belt, the icy ring of debris beyond Neptune that has long been treated as a relatively simple torus of ...

A vast region of our solar system, called the Kuiper belt, stretches from the orbit of Neptune out to 50 or so astronomical units (AU), where an AU is the distance between Earth and the sun. This ...

There may be a warp in the Kuiper Belt, possibly caused by “Planet Y” — a Mercury-to-Earth-sized world that orbits the sun way beyond the orbit of Neptune. Is there a mysterious “Planet Y” orbiting ...