Astronomers are closing in on one of the most tantalizing possibilities in planetary science, evidence that a previously unknown world may be lurking in the outer reaches of the solar system. The ...

Add Yahoo as a preferred source to see more of our stories on Google. An illustration showing Planet Nine, a hypothetical, undiscovered planet in our solar system. New research now suggests the ...

Glasgow Clyde College is preparing to make history by broadcasting a lecture into outer space as part of a new course ...

In the remote outer reaches of planetary systems, far beyond the orbit of known planets, enormous and mysterious worlds silently loop around their stars. Some drift as far as 10,000 times the distance ...

After studying thousands of computer simulations of the solar system, researchers at Rice University and the Planetary Science Institute think there’s a 40% chance an elusive “Planet Nine” or “Planet ...

Ammonite was discovered using the Subaru Telescope in Hawaii, with follow-up confirmation from the Canada-France-Hawaii Telescope. Its orbit and size officially qualify it as a distant dwarf planet.

The Solar System is a weird place filled with incredible physics and geological oddities that often break down in human terms ...

LONDON — The search for an unknown planet in our solar system has inspired astronomers for more than a century. Now, a recent study suggests a potential new candidate, which the paper's authors have ...