NASA asteroid-sampling spacecraft looks at 'the mess it made' on Bennu - CNET
"The Osiris-Rex team decided to add this last flyover after Bennu's surface was significantly disturbed by the sample collection event," NASA said."During touchdown, the spacecraft's sampling head sunk 1.6 feet (48.8 centimeters) into the asteroid's surface and simultaneously fired a pressurized charge of nitrogen gas." The thrusters fired to back Osiris-Rex away also disturbed the surface.
The spacecraft edged in to a distance of a mere 2.1 miles (3.5 kilometers) away from the asteroid's surface, marking its closest approach since the sample collection took place.