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

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

Scientists suggest an interstellar visitor may have altered planetary orbits in our Solar System, reshaping trajectories of ...

Outreach Coordinator Shea Harris said it is an accurate model of the solar system, at one ten-billionth of its actual size. “It kind of gives you a feeling of how big our solar system is as you ...

A planet-size object that possibly once visited the solar system may have permanently changed our cosmic neighborhood by warping the orbits of the four outer planets, a new study suggests.