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 ...

When you see art of our solar system as the planet orbit the sun, you may notice that Earth's orbit has a tilt. It is not a perfect circle. What's more, Earth is not the only planet that displays such ...

Add Yahoo as a preferred source to see more of our stories on Google. An illustration showing Planet Nine, a hypothetical, undiscovered planet in our solar system. New research now suggests the ...

Jupiter, the largest planet in the solar system, may have been responsible for a mysterious age gap in the early solar system's planet building blocks. Credit: NASA / JPL-Caltech / SwRI / MSSS / Tanya ...

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 ...

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 ...

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 dubbed ...

Astronomers have discovered fresh evidence suggesting the possible existence of an unseen planet in the far reaches of our solar system. The study, published in the Monthly Notices of the Royal ...

Researchers estimate that the planet has about a 50% chance of being in its star's Hoble zone.