The diamond-shaped asteroid Bennu has a boulder "witch mole" and a whole lot of other lumps and bumps, a gorgeous new video reveals.
The photos that make up the video were captured last Friday (Nov. 2) by NASA's OSIRIS-REx spacecraft, which has nearly caught Bennu after a two-year chase that began with the probe's September 2016 launch.
"We've now been able to see asteroid Bennu from all sides! The @OSIRISREx PolyCam camera captured an image of every 10 degrees of Bennu's rotation over a four-hour-and-11-minute period on Nov. 2. These images were taken at about 122 miles from the spacecraft," officials at NASA's Goddard Space Flight Center in Greenbelt, Maryland, said via Twitter on Tuesday (Nov. 6). [OSIRIS-REx: NASA's Asteroid Sample-Return Mission in Pictures]
And in another recent set of images from OSIRIS-REx, the 1,640-foot-wide (500 meters) Bennu comes into increasingly sharp focus as the spacecraft makes a gradual approach.
While folks on Earth were fine-tuning their Halloween costumes, the OSIRIS-REx PolyCam was using its long-range capabilities to take almost daily shots of Bennu as it emerged from the murky darkness of space. The sequence, published on Nov. 2 by NASA, includes a total of 16 images.
PolyCam snapped the first image of Bennu in this sequence on Oct. 12 from a distance of 27,340 miles (44,000 kilometers), which is longer than a full lap around Earth's equator. OSIRIS-REx took the sequence's final image on Oct. 29 from about 200 miles (320 km), or roughly the distance between Washington, D.C., and New York City.
If all goes according to plan, OSIRIS-REx will arrive at Bennu on Dec. 3, then slip into orbit around the asteroid on Dec. 31. The probe will study the asteroid up close for about two years, and swoop down to snag a sizable sample from its surface. This material will come to Earth in a sample-return capsule in September of 2023.
Researchers around the world will then pore over the sample, looking for clues about the solar system's early days and the role that carbon-rich asteroids such as Bennu may have played in delivering life's building blocks to Earth.
The $800 million OSIRIS-REx mission also has several other subsidiary goals, as indicated by its full name — Origins, Spectral Interpretation, Resource Identification, Security-Regolith Explorer.