Flying autonomously more than 200 million mi. from Earth, NASA's Osiris-Rex spacecraft made a delicate and brief descent to the rocky surface of the small asteroid Bennu, aiming to collect a few pounds of pebbles and soil for return to Earth, the first such sample-return mission for the U.S. The 4.5-hr. touch-and-go maneuver went as planned, though how much material was collected would not be known for several days. The goal was to have the spacecraft's 11-ft.-long sampling arm sweep up between 0.13 and 4.4 lb. (60 grams-2.2 kg) of nickel-sized pebbles and soil from a landing spot named Nightingale near the asteroid's north pole.
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