Asteroid Bennu rotating faster over time: Study

Asteroid Bennu -- a target of NASA's sample return mission -- is spinning faster over time, an observation that may help understand the evolution of asteroids and their potential threat to Earth, scientist say.

Bennu is located 110 million kilometers away from Earth. As it moves through space at about 101,000 kilometers per hour, it also spins, completing a full rotation every 4.3 hours.

Last year, the Origins, Spectral Interpretation, Resource Identification, Security-Regolith Explorer (OSIRIS-REx) spacecraft arrived at Bennu, the asteroid it will be studying and sampling over the next several years.

The research, published in the journal Geophysical Research Letters, found that the asteroid's rotation is speeding up by about one second per century.

In other words, Bennu's rotation period is getting shorter by about one second every 100 years.

While the increase in rotation might not seem like much, over a long period of time it can translate into dramatic changes in the space rock, .