“For the ICESat-2 POD/PPD team's exceptional performance and innovative approaches to meeting the ICESat-2 mission's stringent geolocation requirements.”
Congratulations to Emergent’s Taylor Thomas, Timothy Rebold, Jennifer Beall and Joseph Nicholas! The Ice, Cloud, land, and Elevation Satellite-2 (ICESat-2) Precision Orbit Determination and Geolocation Parameter Calibration (POD&GPC) and Precision Pointing Determination (PPD) team has performed with the highest standards throughout the mission design, development and operations phases of the mission and thus has been awarded a Robert H. Goddard Honor Award for their exemplary work. POD is a complex multi-disciplinary problem that is at the core of geodetic satellite mission data analysis and product generation. The POD/PPD team provided the key analysis that indicated the cause of the pointing control issues that plagued the early mission. The team provided the only detailed analysis and characterization of the full error signal. Without the team's expertise, analysis and capabilities, the full error signal would not have been observed which would have significantly hampered diagnosis and correction of the Star Tracker reference frame error. Once corrected, the team conducted analysis and developed an approach to successfully correct the many months of data that had been collected enabling these data for science.
The team has also conducted analysis and calibration of pointing control, providing calibration quaternions that are uploaded to the spacecraft to correct the pointing control. Through analysis and calibrations, the team is credited in getting ICESat-2 to meet and exceed its pointing control requirements. This is a significant accomplishment considering the stellar side of the Laser Reference System (LRS) is not operating properly. Without the LRS stellar side, the team's unique frame calibrations were the key to getting the mission to meet and exceed the pointing control requirements. Additionally, during mission development, the team designed the mission orbit and the fundamental reference ground track and vegetation track sampling strategy. The team also developed a unique reference ground track specific coordinate system fundamental to the science data products. The team developed the detailed geolocation algorithms as well as the innovative geolocation parameter calibration strategy and pre-launch simulations and analysis. The ICESat-2 POD/PPD team has provided excellent technical leadership and innovation meeting many mission challenges while ensuring mission performance meets and exceeds requirements to preserve the mission's fundamental science. “POD is as much an art as it is science, and there are only a few organizations in the world that have the required skills and experience, and NASA Goddard is one of them”, said Dr. George Davis, Emergent CEO. “We are proud of our employee’s contributions to the ICESat-2 POD team, they are a key part of an elite enterprise”.
“For the CAMS team's outstanding performance and innovative problem-solving, exceeding requirements for ICESat-2 operational constraint-mitigation and science operations”
Congratulations to Timothy Rebold, Jennifer Beall, Aseel Syed of Emergent, Teresa Pennington of KBR, and Terrence Sabaka and Scott Luthcke of NASA GSFC for being awarded NASA’s Robert H. Goddard Honor Award for their exceptional work on the ICESat-2 Constraint Analysis and Monitoring System (CAMS). The team has performed at the highest level while meeting numerous technical challenges. CAMS was implemented as an ICESat-2 ground system element to provide precise monitoring and active compliance for observatory and instrument operational constraints, and space asset laser conjunction detection and avoidance. In addition, CAMS is the interface between the Project Science Office (PSO), the Instrument Support Facility (ISF) and the Mission Operation Control (MOC). CAMS builds the Science Activity Timeline by ingesting inputs received from the PSO and ATLAS Sustaining Engineering Team (ASET), and deconflicts them against mission planning inputs from the MOC and observatory, including science and instrument constraints. Furthermore, CAMS can implement alternative attitude maneuvers to prevent detected constraint violations or mitigate potential laser conjunctions.
The CAMS team worked together to ensure both the ICESat-2 ATLAS instrument and other space-asset safety, while supporting the implementation and execution of mission science operations. This experienced team provided detailed dynamic modeling, analysis, and prediction of instrument and mission constraint violations and laser conjunctions with other space assets. With quick response the team designed and developed the unique tools and system to meet the mission requirements.
The team's knowledge has been called on numerous times to resolve mission issues, ranging from maneuver re-planning to diagnosing and correcting spacecraft issues, to correcting spacecraft pointing control, to avoiding laser conjunctions with our most valuable space assets including manned vehicles to the ISS. The team's skills were unexpectedly invaluable in the wake of the Star Tracker initialization error and the Laser Reference System star-side failure. Those skills were critical for determining pointing bias corrections and for achieving mission pointing requirements. The team also used its unique skills and tools to diagnose and identify a significant spacecraft pointing control problem post-safehold. The CAMS team, along with the GSFC POD team, analyzed the data against modeled data and determined that the spacecraft ADS had a 19-second timing bias which was the result of erroneous system initialization post-safehold.
The innovative CAMS development team exemplifies the unique ability of NASA GSFC to leverage the deep space geodesy knowledge and experience of its combined civil servant/contractor team to design and develop a sophisticated system to ensure mission safety, space-asset safety, and science operations, and to provide innovative engineering solutions to numerous mission challenges. “The CAMS systems demonstrates Emergent’s ability to integrate mission critical software into the ground system of an operational NASA satellite mission that is critical to our nation’s understanding of climate change” said Dr. George Davis, Emergent CEO. “Laser conjunction avoidance is related to the long-standing problem of physical conjunction avoidance, but there are subtle differences that made the implementation and operation of CAMS highly challenging. We are proud of our team’s contributions to the safe operation of this exciting and important mission”.