The recently spotted asteroid 2025 PN7 appears to be the source of the rumor mill about Earth's supposed second moon. Earth has several quasi-moons that get their name due to the fact that they ...

The moon is our constant companion and the only natural object that always orbits Earth. It's about four times smaller than Earth and its gravity is much weaker, which is why astronauts bounce around ...

So far, humanity has yet to find its first "exomoon"—a moon orbiting a planet outside of the solar system. But that hasn't been for lack of trying. According to a new paper by Thomas Winterhalder of ...

About 4.5 billion years ago, a colossal impact between the young Earth and a mysterious planetary body called Theia changed everything—reshaping Earth, forming the Moon, and scattering clues across ...

March’s “worm moon” sets behind Rocca Calascio castle and village in L’Aquila, Italy. Photograph by Lorenzo Di Cola, NurPhoto/Getty Images Earth’s moon phases cycle from month to month, waning and ...

The big astronomical event in February is a rare “planetary parade,” according to NASA. You’ll be able to see Mercury, Venus, ...