A Neptune-sized planet, TOI-3261 b, makes a scorchingly close orbit around its host star. Only the fourth object of its kind ever found, the planet could reveal clues as to how planets such as ...

The number of planets that orbit the sun depends on what you mean by “planet,” and that’s not so easy to define ...

Beyond Neptune lies the Kuiper Belt, a vast expanse of icy bodies that may hold clues to the solar system’s formation. These ...

An object eight times the mass of Jupiter may have swooped around the sun, coming superclose to Mars' present-day orbit ...

Kuiper Belt, well past the orbit of Neptune (artistic illustration). There may be an undiscovered planet in the outer solar system whose presence is revealed by the strange orbit of objects beyond ...

It probably spent nearly all of the past 4.5 billion years in a deep freeze beyond Neptune, inside the comet Wild 2 (pronounced VILT-two). Decades ago Wild 2 somehow got nudged into an orbit that ...

Pluto resembles the icy, comet-like objects orbiting the Sun outside of Neptune's orbit, rather than either the rocky terrestrial planets or the Jovian planets. Factors that distinguish Pluto from ...

Four planets will be in the parade in January, while seven will align in February. Here's how to see the events.

Its 29-Earth-year orbit results in seasonal shifts roughly ... with the Uranian ring system appearing face-on in 2028. Neptune's OPAL observations revealed two significant findings.