Engadget has more info over here:
We already know lots of other things about Bennu, including the fact that it’s spewing particles into space — behavior that’s common for a comet, but rare for an asteroid. Scientists also discovered that it’s surprisingly rugged, as is clear by the number of boulders strewn on its surface. They also found the presence of magnetite, indicating that it likely interacted with water on Bennu’s parent body.Full-size versions can be found over here but be aware that the 50,669 x 25,350 pixels full version is 859MB.