For the dwarf planet candidate, one trip around the sun takes over 24,000 years. Its orbit challenges a proposed path for a hypothetical Planet Nine.

the flybys that had previously altered the giant planets' orbits to their present states recreated the solar system's current ...

More than 150 moons orbit worlds in our solar system. Known as natural satellites, they orbit planets, dwarf planets, asteroids, and other debris. Among the planets, moons are more common in the ...

Today, it’s believed that Jupiter and Saturn, the largest planets, were the first to fully form, both within a few million ...

For years, scientists have puzzled over how these "wide-orbit" planets ... in realistic star cluster environments. They modeled a variety of conditions, from systems like our solar system with ...

Pluto was reclassified as a dwarf planet in 2006. Our solar system may have a ninth planet after all, researchers say. The possibility that an additional planet may be hidden far into the solar ...

With stunningly realistic animations ... the forces driving the dramatic weather on neighboring planets and moons. NOVA: Solar System: Storm Worlds Preview Episode 2: “Strange Worlds ...

Are planets in the solar system that are closer to the Sun older than the ones further away? – Gavriel, age 10, Paducah, Kentucky A cloud of collapsing gas created our Sun, the first thing to ...