Jupiter is already the biggest planet by far in our solar system, but new research suggests it was somehow once even larger than it is now. Twice as large, in fact. To put that into context, those ...

An international team of astronomers has discovered a distant planetary system that challenges long-standing theories of how ...

Updated measurements from NASA’s Juno spacecraft could help researchers better understand the planet's mysterious interior, ...

A newly studied solar system breaks the usual planet pattern, raising fresh questions about how rocky and gas planets form.

When you buy through links on our articles, Future and its syndication partners may earn a commission. A composite image comparing the relative sizes of our solar system's known dwarf planets, ...

Scientists say a nearby red dwarf star hosts a planetary lineup that looks like a mirror image of our own solar system, with ...

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 ...