Short-lived radioisotopes such as aluminum-26 influenced early solar system heat, water retention and the formation of Earth-like rocky planets, according to meteorite analyses and models.

Across the Milky Way and beyond, planetary systems appear to fall into a few recurring blueprints, and recent exoplanet ...

For centuries our solar system was the only planetary system known to humans. We had no proof other worlds existed beyond those in our own cosmic backyard, and we imagined that if other planetary ...

With sapphire waterfalls, lava rain and orbits around dead stars, these distant worlds push the limits of what’s possible.

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 ...

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 form in ...

From Viking to Perseverance, scientists have spent decades chasing chemical hints that could point to life beyond Earth.

Most planets are part of a star system of their own – but some go their own way, and they have remained largely mysterious ...

Rocky planets like our Earth may be far more common than previously thought, according to new research published in the journal Science Advances. It suggests that when our solar system formed, a ...

When I was a kid, there were nine planets. Now we know of thousands! But that includes exoplanets, alien worlds that orbit alien suns. Only eight planets call our solar system home. Or there might ...

How common are Earth-like planets in the universe? When I started working on supernova explosions, I never imagined that my ...

When two giant planets collide, an even bigger world may be born. When you purchase through links on our site, we may earn an affiliate commission. Here’s how it works. Based on new simulations, ...