In short: A new study, yet to be peer reviewed, builds on years of evidence suggesting a ninth planet exists in the Solar System. Despite this, researchers have not yet seen it directly using ...

Australian volunteer citizen scientists have found four previously unknown planets orbiting a nearby star thanks to a crowd-sourcing project aired on the ABC's Stargazing Live. The four "Super Earth" ...

(Ianm35/iStock/Getty Images Plus) The Solar System is one of the comforting constants of human existence. No matter what else ...

The catastrophic collision that forged the moon, and marked one of the most consequential events in Earth's early history, may have been triggered not by a distant interloper, but by a sibling world ...

Astronomers are closing in on one of the most tantalizing possibilities in planetary science, evidence that a previously unknown world may be lurking in the outer reaches of the solar system. The ...

An exoplanetary system about 116 light-years from Earth could flip the script on how planets form, according to researchers who discovered it using telescopes from NASA and the European Space Agency, ...

We have all been taught in school that planets revolve in the same direction as the Earth, i.e., in the counterclockwise direction. However, the universe never ceases to amaze us with its unexpected ...

Even at a glance, the planets in our solar system are wildly diverse. Huge and small, airless and densely packed with atmosphere, they have a wide range of characteristics distinguishing them. But if ...

The Multi-object Apache Point Observatory Radial Velocity Exoplanet Large-area Survey (MARVELS) is set to survey about 11,000 stars. Beginning in 2008, astronomers hope to find at least 150 planets ...