LADEE Project Manager Update: LADEE at the Moon
During the recent government shutdown that lasted thru Oct. 16, NASA’s Lunar Atmosphere and Dust Environment Explorer (LADEE) mission continued to perform critical maneuvers and was captured into its commissioning orbit around the moon. The trajectory correction maneuver (TCM-1) on Oct. 1, set the spacecraft on course to rendezvous with the moon on Oct. 6.
The first Lunar Orbit Insertion maneuver (LOI-1) on Oct. 6, was a real nail-biter for the team, because missing that maneuver would have made it very difficult for LADEE to achieve a lunar orbit and perform the science mission. Fortunately, the LOI-1 engine burn was very accurate, and required no additional course adjustments. This maneuver successfully put the spacecraft in a 24-hour elliptical lunar orbit. The LOI-2 maneuver on Oct. 9, also was very accurate, and placed LADEE in a four-hour elliptic lunar orbit. The third and final burn (LOI-3) occurred on Oct. 12, and put the spacecraft into its current two-hour commissioning orbit at approximately 145-155 miles (235-250 km) above the lunar surface .
After arriving at the moon, the LADEE spacecraft first performed commissioning activites to make sure the spacecraft was operating correctly in that orbit. Those activities are now complete, and the instrument commissioning activities have begun.
All instruments onboard LADEE have covers to protect them during launch and cruise, and are ejected – or deployed – at various times as LADEE travels to the moon. The cover for the Lunar Laser Communications Demonstration (LLCD) was deployed on Sept. 27, in order to perform an early acquisition calibration test. The Neutral mass Spectrometer (NMS) cap was ejected on Oct 3, just prior to LADEE’s arrival at the moon, so that it would not become a hazard to the spacecraft. The Lunar Dust EXperiment (LDEX) and Ultra Violet Spectrometer (UVS) aliveness activities were successfully completed on Oct. 16, with the deployment of both instrument covers.
These instrument cover deployments were the last remaining planned critical events for the mission. This means there are no further show-stoppers before the science phase begins. All of the critical maneuvers and all instrument cover deployments are now completed. The science instrument commissioning and LLCD primary experiment will be conducted through mid-November, at which point the spacecraft will descend to the lower lunar orbit and perform science measurements.
Butler Hine
NASA’s Ames Research Center, Moffett Field, Calif.
