A planetary system 116 light-years from Earth has a peculiar pattern. It could flip the script on how planets form, ...

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 ...

Astronomers have found a distant world that challenges planetary formation theory, with a rocky planet where gas giants should be.

Astronomers have uncovered a distant planetary system that flips a long-standing rule of planet formation on its head. Around the small red dwarf star LHS 1903, scientists expected to find rocky ...

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 ...

Astronomers have spotted an unusual 'inside-out' planetary system where a rocky world seems to have formed far beyond the realm typically reserved for gas giants.

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 ...