In 2016, a pair of astronomers made an exciting announcement: There might be a hidden planet about ten times the size of Earth lurking somewhere in the most distant part of our solar system, waiting ...

January 5, 2005, is an astronomical anniversary that is not really marked but should be. It saw the discovery of dwarf planet Eris and how those very observations led to a new way to describe the ...

The New Horizons Pluto flyby revealed unexpectedly complex geological features on dwarf planets, prompting further investigation into the diversity within the Kuiper Belt. Several dwarf planets, ...

Scientists have been trying to find a hypothetical Planet 9 that may exist outside our known solar system based on the unusual orbits of certain dwarf planets. But those orbits might not require a ...

Object 90377 Sedna — a distant trans-Neptunian object known best for its highly elliptical, 11,390-year-long orbit — is currently on its way towards perihelion (its closest approach to the Sun) in ...

Bumper car-like interactions at the edges of our solar system—and not a mysterious ninth planet—may explain the dynamics of strange bodies called “detached objects,” according to a new study. CU ...

DENVER — Small but rowdy space rocks pushing and jostling one another may have created the unusual orbits some astronomers cite as the signature of the hypothesized "Planet Nine," a new study suggests ...

Forbes contributors publish independent expert analyses and insights. I am a writer specializing in physics, astronomy, and related topics. The outermost Solar System is a confusing and complicated ...

Bumper car-like interactions at the edges of our solar system -- and not a mysterious ninth planet -- may explain the dynamics of strange bodies called 'detached objects,' according to a new study.