Mercury has long baffled astronomers because it defies much of what we know about planet formation. A new space mission ...

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

There could be a ninth planet in our solar system that's lying in wait to be discovered - and no, it's not Pluto. Our solar ...

UNDATED (WKRC) - Astronomers recently made an important discovery when they found a rare "in-sync" solar system with six planets all moving in one big grand harmony, completely untouched by outside ...

Astronomers using planet-hunting satellites have discovered a rare solar system with six planets moving completely in sync with one another, as if they were untouched by any outside force since being ...

Jupiter is the largest planet in the solar system, known for its massive size, strong gravity, powerful storms and many moons ...

CAPE CANAVERAL, Fla. — Astronomers have discovered a rare solar system in the Milky Way that boasts six planets orbiting in perfect rhythm like a cosmic orchestra, untouched by outside forces since ...

"This is really like looking at ourselves in a funhouse mirror." When you purchase through links on our site, we may earn an affiliate commission. Here’s how it works. Skewed planetary pathways around ...

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

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

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 ...

The International Astronomical Union (IAU) defines a planet as a celestial body orbiting the Sun, possessing sufficient mass for a nearly spherical shape, and having cleared its orbital neighborhood ...