If the object really is Planet Nine, it would be larger than Neptune and exist 700 times further from the sun than Earth.

A new study, however, identifies a possible candidate. A separate team of astronomers compared 1983 data from the Infrared ...

Astronomers searching for a ninth planet in our solar system say they've found a "good" candidate far beyond Neptune, according to a new preprint study. This could be humanity's first glimpse at the ...

Our solar system may have a ninth planet after all, following the declassification of Pluto nearly two decades ago, ...

Caroline Delbert is a writer, avid reader, and contributing editor at Pop Mech. She's also an enthusiast of just about ...

"The outer solar system is theoretically predicted to harbor an undiscovered planet, often referred to as Planet Nine," the ...

A ninth planet the size of Neptune may be hidden in the far reaches of the solar system, but the evidence has left some experts skeptical.

Scientists may have just spotted Planet Nine — a massive object orbiting 700 AU from the Sun. Data from two space telescopes ...

Astronomers have long speculated about an unseen planet lurking in the solar system's outer edge. This hypothetical world, dubbed Planet Nine, could explain the unusual clustering ...

Astronomers claim to have discovered a new ninth planet in our Solar System. Planet Nine, also known as Planet X, is a hypothetical celestial object that would distantly orbit our Sun – but ...