The giant planets weren't always where we find them today. Jupiter, Saturn, Uranus and Neptune formed in a more compact ...

Fantasizing about interplanetary exploration is a fun mental exercise, but the harsh realities of life (or lack thereof) in ...

When it comes to planets in our Solar System's habitable zone, one world is too close to the Sun, another is too far and ...

This artist’s concept depicts one of the solar system’s inner planets slamming into Earth after being nudged on a collision course by a passing star. Such a world-shattering cataclysm is extremely ...

New high-contrast images from SPHERE show a stunning variety of debris disks shaped by collisions of tiny planet-building ...

A vast ring of rocky leftovers between Mars and Jupiter, the asteroid belt preserves clues to how the planets — and Earth ...

Even the best telescopes can’t see exoplanets. It’s all about watching for jiggly stars, blue shifts, and transits.

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 ...

(CNN) — The search for an unknown planet in our solar system has inspired astronomers for more than a century. Now, a recent study suggests a potential new candidate, which the paper’s authors have ...

Astronomers are uncovering distant worlds beyond our solar system using ingenious indirect methods like observing stellar ...