Dawn completes first 30-day health assessment in lunar orbit

The Dawn lunar landing system has completed its first 30-day on-orbit health assessment after arriving in lunar polar orbit on 2 June. Flight controllers reviewed propulsion, power, thermal control, guidance, navigation, communications and vehicle-management data collected during 428 lunar orbits.

All primary systems remain within certified flight limits. Propellant reconciliation is within 0.18 percent of the preflight prediction, and battery performance shows no measurable capacity loss. Thermal-control heaters operated for less time than the conservative preflight model, preserving additional electrical margin for the crewed phase.

Dawn completed two orbit-maintenance burns and a navigation-camera calibration over the ALEP 15 landing region. Hazard-relative navigation imagery has been cross-registered with Farpoint radar topography, reducing the predicted landing-ellipse uncertainty ahead of final target upload.

The vehicle will remain in its 104-by-117-kilometre staging orbit until Resolve arrives with the ALEP 15 crew. Controllers will continue weekly functional checks and will perform a full propulsion-system readiness sequence 21 days before the target crew launch.