For a long time, children learning about space in school were taught that there were nine planets in our solar system. Then, ...

Scientists have been on the hunt for a possible ninth planet in our solar system for some time. The existence of this elusive ...

Our solar system used to have nine planets ... objects beyond Neptune’s orbit that also happens to be the former ninth planet’s neighborhood. The 2005 revelation set off a chain of events ...

Ever since Pluto was demoted from planet status, astronomers believe a real Planet Nine exists in the solar system ...

The tantalizing prospect of a ninth planet is suggested by a paper ... or a few such new TNOs could revolutionize our theories about how the solar system formed,” said Lykawka.

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.

The solar system may be hosting a ninth planet that is about 10 times bigger than Earth and orbiting far beyond Neptune, according to research published in the Astronomical journal. Astronomers ...

Pluto was previously classed as the ninth planet from 1930 to 2006 ... and moons – or even travel much further, away from our solar system. Space probes have been sent to observe the outer ...