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ADS helps reboot ISEE-3 with ODTK and STK Astrogator

By: Tim C
Applied Defense Solutions (ADS) and Space Exploration Engineering (SEE) are working in collaboration with SkyCorp and NASA on the reboot project of the International Solar-Environment Explorer (ISEE-3) spacecraft. The ADS/SEE team, comprised of Lisa Policastri, Craig Nickel, Mike Loucks, and myself are applying our astrodynamics expertise in trajectory design, orbit determination, and maneuver planning to help Skycorp in determining the location of ISEE-3. We are trying to determine the spacecraft’s current trajectory and the necessary maneuvers to achieve the desired trajectory. Determining the spacecraft’s trajectory and the best course of action to get to the desired trajectory has proven to be particularly challenging due to the lack of data we have. We only get a couple of measurements every other day. In addition, the satellite geometry does not change much with respect to the Earth. Because of that, we have limited observables making our uncertainties large. To assist us in the analysis, the team is using AGI’s suite of software, which we have relied on in the past for missions that are not Earth centered, such as the Interstellar Boundary Explorer (IBEX) and the Lunar Atmosphere and Dust Environment Explorer (LADEE). The products we rely on heavily are Orbit Determination Tool Kit (ODTK) and STK Astrogator. The team has configured ODTK to process tracking measurements currently provided by the Arecibo radio telescope. NASA has approved the use of the Deep Space Network (DSN) for tracking that the team expects to process with ODTK. By using ODTK, the team is able to understand the uncertainties in the data and to simulate what those uncertainties might look like with additional tracking and/or different types of tracking. ODTK also provides the insight that we need to request the appropriate ground stations for tracking purposes. When it came to designing the trajectory for ISEE-3, we used STK Astrogator. The trajectory analysis includes the design of specific maneuvers that enable the spacecraft to swing by Earth’s Moon in early August. The lunar swing-by enables the spacecraft to be re-captured by the Earth-Moon system, allowing it to be maneuvered into a scientific orbit. Below is an animation created by Mike Loucks at SEE of the ISEE-3 reboot trajectory:
Posted: 6/23/2014 7:48:35 PM