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

Scientists have been able to recreate the extreme conditions found on icy moons in deep space—and revealed the unstable ...

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

The celestial body's unusual orbit “implies that something extraordinary occurred" in the early days of the solar system—and ...

Analysis of an ancient meteorite suggests that rocky planets both near and distant from the sun may have formed at the same ...

The solar system consists of eight planets, several dwarf planets, hundreds of moons, and billions of asteroids, comets and ...

The newly discovered world — a "sednoid" — challenges what planetary scientists thought they knew about the edge of the solar ...

"It is possible that a planet once existed in the solar system but was later ejected, causing the unusual orbits we see today ...

Astronomers have discovered the earliest seeds of planets forming around HOPS-315, a baby star located 1,300 light-years away ...

International astronomers have for the first time witnessed the birth of a planetary system beyond Earth's sun that could one ...

The star is surrounded by a protoplanetary disk, and this disk is the first evidence of debris condensing into what will ...