CAPE CANAVERAL, Fla. – A NASA spacecraft descended Tuesday toward the surface of an asteroid 200 million miles away to collect a handful of rubble for return to Earth.The Osiris-Rex spacecraft dropped out of orbit around asteroid Bennu right on time, beginning a 4 1/2-hour plunge to the rough, boulder-covered face of the ancient space rock.
It was America's first attempt to gather samples from an asteroid, something already accomplished by Japan — twice.Bennu’s gravity was too low for the spacecraft to land — the asteroid is just 1,670 feet (510 meters) across.