The astronomers observed hot minerals just beginning to solidify – the first specks of planet-forming material, the ...

Evidence that rocky planets beyond Jupiter formed as rapidly, and at the same time, as the inner planets could transform our ...

Is there a massive undiscovered planet on the outer reaches of the solar system? The idea has been around since before the ...

Currently, our solar system recognizes 8 planets, with Pluto being demoted to a dwarf planet floating in the Kuiper Belt in 2006. Planet Nine's gravitational pull may explain what keeps the icy ...

CAPE CANAVERAL, Fla. (AP) — Astronomers have discovered the earliest seeds of rocky planets forming in the gas around a baby ...

Mike Brown is convinced that beyond Neptune, at the far reaches of our solar system, there's an unseen giant planet. "This is the 5th largest planet in our solar system, lurking out there, waiting ...