NASA'S OSIRIS-REx zooms in on Bennu

This set of 16 images shows the OSIRIS-REx spacecraft's steady approach toward the asteroid Bennu during the last half of October 2018. From Oct. 12 to Oct. 29, the long-range PolyCam camera took one optical navigation image per day, except on Oct. 16 and 17 when PolyCam was not scheduled to take images. The spacecraft was approximately 27,340 miles (44,000 km) from Bennu for the first image - a distance several thousand miles greater than the circumference of the Earth. The last image was taken from a distance of around 200 miles (320 km), or slightly less than the distance between Los Angeles and Las Vegas. NASA's OSIRIS-REx spacecraft executed its third Asteroid Approach Maneuver (AAM-3) today. The trajectory correction maneuver (TCM) thrusters fired in a series of two braking maneuvers designed to slow the spacecraft's speed relative to Bennu from approximately 11.7 mph (5.2 m/sec) to .24 mph (.11 m/sec). Due to constraints that science instruments not be pointed too closely to the Sun, this maneuver was designed as two separate burns of approximately 5.8 mph (2.6 m/sec) each, to accomplish a net change in velocity of around 11.5 mph (5.13 m/sec).

The mission team will continue to examine telemetry and tracking data over the next week to verify the new trajectory. The maneuver targeted the spacecraft to fly through a corridor designed for the collection of high-resolution images that will be used to build a shape model of Bennu.

The OSIRIS-REx spacecraft is in the midst of a six-week series of final approach maneuvers. AAM-1 and AAM-2, which executed on Oct. 1 and Oct. 15 respectively, slowed the spacecraft by a total of approximately 1,088 mph (486 m/sec). The last of the burns, AAM-4, is scheduled for Nov. 12 and will adjust the spacecraft's trajectory to arrive at a position 12 miles (20 km) from Bennu on Dec. 3.