There have been questions about a mysterious ninth planet in our solar system for nearly a decade. Pluto was unseated as number nine in 2006. Now, a group of international researchers say they may ...

There are 8 planets in our solar system. The planets orbit the Sun in elliptical trajectories, and they are all different in size, composition, temperature, and characteristics. The planets can be ...

This article was originally featured on The Conversation. 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 ...

Pluto was reclassified as a dwarf planet in 2006. Our solar system may have a ninth planet after all, researchers say. The possibility that an additional planet may be hidden far into the solar system ...

Lucas Brefka receives funding from a NASA Exoplanet Research Program grant. Christopher Palma does not work for, consult, own shares in or receive funding from any company or organization that would ...

Astronomers have discovered that the Jupiter, the largest planet in our Solar System, was once so big that it could have held 2,000 Earths. Jupiter is our system's oldest planet, forming from the dust ...

A tiny meteorite is rewriting what scientists thought they knew about the origins of our solar system. New evidence found in shavings from a meteorite known as Northwest Africa 12264 — a 50-gram (1.8 ...

Every year, Earth follows a familiar pattern of seasonal changes: As summer rolls around in the Northern Hemisphere, winter creeps in in the Southern Hemisphere, and vice versa. But do other planets ...

Our solar system is a smashing success. A new study suggests that from its earliest period — even before the last of its nebular gas had been consumed — Earth’s solar system and its planets looked ...