A distant, icy body circling the Sun far beyond Neptune has handed astronomers a fresh puzzle. Designated 2023 KQ14 and nicknamed Ammonite, the trans-Neptunian object follows a Sedna-like orbit with a ...

Two faint objects hiding in archival infrared sky maps now sit at the center of a growing scientific argument about whether a massive, unseen planet orbits far beyond Neptune. Researchers mining data ...

Add Yahoo as a preferred source to see more of our stories on Google. Scientists think there may be a ninth planet hiding in the distant reaches of the solar system — and a new telescope could finally ...

Planet Nine, the undiscovered planet at the edge of the solar system that was predicted by the work of Caltech’s Konstantin Batygin and Mike Brown in January 2016, appears to be responsible for the ...

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 ...

It might be lingering bashfully on the icy outer edges of our solar system, hiding in the dark, but subtly pulling strings behind the scenes: stretching out the orbits of distant bodies, perhaps even ...

The solar system consists of our star, the sun, and everything bound to it by gravity: the planets Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune, along with dwarf planets like ...

In the cold, dark outskirts of planetary systems far beyond the reach of the known planets, mysterious gas giants and planetary masses silently orbit their stars—sometimes thousands of astronomical ...

Forbes contributors publish independent expert analyses and insights. An award-winning reporter writing about stargazing and the night sky. Is there an unseen planet — a "planet X" or "Planet Nine" — ...