A planetary system 116 light-years from Earth has a peculiar pattern. It could flip the script on how planets form, scientists say.

Gas giants possibly developed slowly in the solar system. They developed cores layer by layer within a disk of ice and dust ...

Astronomers have found a distant world that challenges planetary formation theory, with a rocky planet where gas giants should be.

Add Yahoo as a preferred source to see more of our stories on Google. Are planets in the solar system that are closer to the Sun older than the ones further away? – Gavriel, age 10, Paducah, Kentucky ...

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

Add Yahoo as a preferred source to see more of our stories on Google. Digital art of distant planet - Dottedhippo/Getty Images On August 24, 2006, our solar system lost a planet. It wasn't by ...

HR 8799, located 129 light-years away, is home to a rare group of super-Jupiters, gas giants that are much larger than our own Jupiter. These planets, orbiting far from their star, present a unique ...

Since the 1990s, scientists have discovered approximately 6,100 planets outside our solar system, called exoplanets.

At the farthest edges of the solar system, strange objects follow paths that defy easy explanation. This story investigates ...

LONDON — 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 ...

With this new survey, astronomers have gained a peek inside a stage of exoplanet system formation they have yet to fully ...