GREENBELT, Md. (NASA PR) — Captured on Apr. 14 during the first rehearsal of the OSIRIS-REx mission’s sample collection event, this series of images shows the navigation camera’s (NavCam 2) field of view as the NASA spacecraft approaches and moves away from asteroid Bennu’s surface.
The rehearsal brought the spacecraft through the first two maneuvers of the sampling sequence to a point approximately 213 feet (65 meters) above the surface, after which the spacecraft performed a back-away burn.
These images were captured over a three-hour period – the imaging sequence begins approximately one hour after the orbit departure maneuver and ends approximately two minutes after the back-away burn. In the middle of the sequence, the spacecraft slews, or rotates, so that NavCam 2 looks away from Bennu, toward space.
Shortly after, it performs a final slew to point the camera (and the sampling arm) toward the surface again. Near the end of the sequence, site Nightingale comes into view at the bottom of the frame. The large, tall boulder situated on the southeastern edge of the crater’s rim is 43 feet (13 meters) on its longest axis. The sequence was created using over 100 images taken by the spacecraft’s NavCam 2 camera.
NavCam 2 captures images for the spacecraft’s Natural Feature Tracking (NFT) navigation system. The NFT system allows the spacecraft to autonomously guide itself to Bennu’s surface by comparing real-time images with an onboard image catalog.
As the spacecraft descends to the surface, the NFT system updates the spacecraft’s predicted point of contact depending on OSIRIS-REx’s position in relation to Bennu’s landmarks. During the sample collection event, scheduled for August, the NavCam 2 camera will continuously image Bennu’s surface so that the NFT system can update the spacecraft’s position and velocity relative to Bennu as it descends towards the targeted touchdown point.
NavCam 2, a panchromatic (black-and-white) imager, is one of three cameras comprising TAGCAMS (the Touch-and-Go Camera System), which is part of OSIRIS-REx’s guidance, navigation, and control system. TAGCAMS was designed, built and tested by Malin Space Science Systems; Lockheed Martin Space integrated TAGCAMS to the OSIRIS-REx spacecraft and operates TAGCAMS.