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 ...

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 ...

Scientists say studying objects like Ammonite, despite their immense distance, offers valuable insight into the solar ...

The curious minds at What If explore a brand new planet forming inside our solar system, imagining its effects on orbits, gravity, and cosmic dynamics.

This discovery was made by two of NASA’s most celebrated telescopes. This illustration provided by Dan Durda shows the exoplanet Kepler-1625b with a hypothesized moon. On Thursday, Oct. 4, 2018, two ...

When my colleagues and I send them out to explore our solar system, it's important for us to understand the 3D map of our ...

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 ...

Planet Y is the latest in a series of hypothetical solar system planets that scientists have proposed in recent years, all with slightly different characteristics but collectively believed to be ...