Although it won’t hit Earth, an asteroid once labeled a “city killer” is now back in the spotlight — this time, because it ...

When a six-mile-wide asteroid slammed into Earth 66 million years ago, it didn’t just wipe out the dinosaurs. New findings ...

Scientists warn the universe could reverse its expansion and collapse in a “Big Crunch” — with the first signs possibly emerging in just 10 billion years.

Gravity isn’t uniform everywhere on Earth. You weigh more at the poles, for instance, than at the equator. Why? This viewer ...

A comet that was born in another solar system and could be billions of years old is hurdling through Earth’s solar system — a ...