Planetary Science

At dusk and dawn, the sky dances with three phases of in-between light

A gigantic space rock that slammed into Earth more than three billion years ago grievously wounded the biosphere—and then helped it heal

We have been adding “leap seconds” to time kept by our atomic clocks, but soon we may have to subtract one. Are the tiny adjustments worth the bother?

For the first time, we are sending a spacecraft to explore an alien ocean world—a moon that might host life today

Hera will arrive in 2026 at Dimorphos, an asteroid deliberately struck by NASA’s DART spacecraft

Claims of worlds orbiting Barnard’s star have been made before. But an advanced instrument could provide the breakthrough that finally confirms the star hosts a planetary system

Sooner or later a doomsday asteroid will wipe out most life on Earth—unless, that is, we prevent threatening space rocks from hitting us in the first place

We are in a new and different kind of moon race, one the U.S. is losing. To win, says a former NASA official, we need new strategies

A small asteroid, 2024 PT5, will spend the next two months alongside our planet as a mini moon before swooping back to deep space

Scientists are putting a new spin on the creation of binary asteroids

We can’t yet tell how life got its start on Earth. That’s one great reason to keep looking for life elsewhere

The world’s richest man, Elon Musk, owes his superstar success to self-satisfied competitors who blew obvious opportunities