Astronomers have a potential Planet Nine candidate, detected via infrared radiation. This candidate's orbit is very different from what's predicted for Planet Nine. The candidate may be a false ...

It's an evocative idea that has long bedeviled scientists: a huge and mysterious planet is lurking in the darkness at the edge of our solar system, evading all our efforts to spot it. Some astronomers ...

A leading scientist has told Newsweek about new evidence supporting the existence of a secret ninth planet lurking at the edge of our solar system. This hypothetical extra planet, often referred to as ...

The mysterious Planet Nine may have up to 20 moons that could be superheated by the hypothetical planet's gravitational pull, making them easy to spot. When you purchase through links on our site, we ...

Scientists think there may be a ninth planet hiding in the distant reaches of the solar system — and a new telescope could finally prove its existence. | Credit: Nicholas Forder for Live Science Deep ...

A possible new dwarf planet has been discovered at the edge of our solar system, so far-flung that it takes around 25,000 years to complete one orbit around the sun. The object, known as 2017 OF201, ...

Earlier this year scientists presented evidence for Planet Nine, a Neptune-mass planet in an elliptical orbit 10 times farther from our Sun than Pluto. Since then theorists have puzzled over how this ...

There has been a lot of back and forth about the existence of a mysterious ninth planet, often referred to as "Planet Nine" or even "Planet X." Now, though, researchers say there is likely at least a ...

Astronomers know very little about the far outer Solar System — beyond Neptune, Pluto, and the far-flung Kuiper belt. For the past seven years, some scientists have observed certain gravitational ...

An artist's illustration of a possible ninth planet in our solar system, hovering at the edge of our solar system. Neptune's orbit is shown as a bright ring around the Sun. Scientists in Taiwan ...