Long ago, a planetary object eight times the mass of Jupiter may have once visited the solar system and altered the orbits of ...

An object eight times the mass of Jupiter may have swooped around the sun, coming superclose to Mars' present-day orbit before shoving four of the solar system's planets onto a different course. When ...

A planet circling at a sharp 90-degree angle to the orbits of its two host stars has now been confirmed. This discovery challenges long-standing ideas about how planets form and orbit in the cosmos.

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 ...