Carl Sagan famously said that "We're all made of star stuff." But he didn't elaborate on how that actually happened. Yes, ...

One of the oldest unsolved riddles in planetary science concerns the origin of the moon. Over a century ago, George Darwin ...

The interstellar comet will pass safely by Earth, giving astronomers their best chance to study it up close. Interstellar ...

The Earth's magnetic field and oxygen evolved together over 540 million years, according to a major NASA study.

An ultra-hot rocky exoplanet may be wrapped in a dense atmosphere, defying expectations about what small planets can sustain.

A vast ring of rocky leftovers between Mars and Jupiter, the asteroid belt preserves clues to how the planets — and Earth ...