There are eight official planets (sorry, Pluto) in our solar system: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and ...

“Because Pluto is rotating rapidly prior to the collision, and because Charon lies mostly outside of their corotation zone, ...

A few decades ago, the Solar System had nine planets, but in 2006 the International Astronomical Union reclassified Pluto as ...

If Brown’s hidden world is real, Rubin will almost certainly find it or strong indirect evidence that it exists. “In the ...

New models reveal Pluto and Charon may have spent some of their early history locked together in an embrace after a grazing ...

Astronomers are on the hunt for a mysterious ninth planet, known as Planet Nine, which could change our understanding of the solar system. Is this hidden world real, or just a myth?

An curved arrow pointing right. Astronomers say they've discovered a ninth planet 200 times farther from the Sun than Earth. Produced by Emmanuel Ocbazghi. Original Reporting by Jessica Orwig.

Opinions expressed by Forbes Contributors are their own. Jamie Carter is an award-winning reporter who covers the night sky. Computer simulations suggest that there is an undiscovered Earth-like ...

We’ll finally get to meet the former ninth planet face-to-face—to really see its surface and that of its largest moon, Charon. Scientists have some guesses about what they might find ...

An curved arrow pointing right. Astronomers have new evidence that seems to confirm Planet 9's existence. Produced by Emmanuel Ocbazghi. Original reporting by Jess Orwig. Follow BI Video ...

She, like her fellow soldiers, do not remember anything about the Ninth Planet - their real memory has been erased, and false memories have been implanted instead.