Researchers have taken a first step toward the "rotating detonation engine," which could make rockets more fuel-efficient and lightweight.

After several months evaluating data from four candidate sites on the asteroid Bennu, scientists have finally identified the best sample collection spot.

"Among Bennu's many surprises, the particle ejections sparked our curiosity, and we've spent the last several months investigating this mystery."

The mission to get a bit of the asteroid Bennu's surface back to Earth in 2023 is facing some unexpected challenges. Here are four new findings.