The catalog of known worlds beyond our solar system has crossed another threshold. NASA’s official tally now exceeds 6,000 ...

Facts about Pluto, the dwarf planet in the Kuiper Belt ...

The hunt for Planet Nine continues as new discoveries make the Solar System’s biggest mystery even harder to solve. Is there ...

Our solar system may have hosted up to six giant planets in its first hundred million years, a new study suggests. The ...

When 'Oumuamua traversed our solar system in 2017 it was the first confirmed Interstellar Object (ISO) to do so. Then in 2019, Comet 2l/Borisov did the same thing. These are the only two confirmed ...

A rare meteorite has revealed evidence of a massive lost world that once orbited the young Sun before being destroyed in a catastrophic collision. The discovery suggests some early planets formed from ...

While life on Mars (and Venus) has long been an obsession for those wondering if we're alone, there are other places in our ...

A village in Kent is home to what is thought to be the world's largest scale model of the solar system and beyond, created to ...

What is Planet Nine, and where is it? The question has fascinated astronomers for years. Scientists believe a massive undiscovered planet may exist in the outer Solar System. Although no telescope has ...

So far, humanity has yet to find its first "exomoon"—a moon orbiting a planet outside of the solar system. But that hasn't been for lack of trying. According to a new paper by Thomas Winterhalder 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 ...