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Syed Hasan

Publications and source records attributed to Syed Hasan.

Conjunction Assessment(CA) Support Overview for the EOS Satellites

When a satellite is placed into its desired orbit, to achieve its designed mission objectives, it is imperative to maintain orbit requirements as well as the overall health and safety of the vehicle. One integral part of this process is ensuring that the satellite does not collide with any other vehicle or object in space, which can cause a detrimental consequence to the mission as well as to other satellites within the same orbit regime. To prevent such an occurrence, a thorough collision avoidance process must be followed. This process includes constantly monitoring potential conjunctions and performing collision avoidance maneuvers when necessary, while remaining within the limitations of the mission’s orbit maintenance requirements. This presentation will describe the Earth Observing System (EOS) Aqua, Aura and Terra satellite’s operational collision a! voidance process. It will highlight the routine conjunction assessment screening and data evaluation process performed by the NASA/GSFC EOS Collision Avoidance Engineers. The presentation will include background information, a summary of operational activities and duties, internal tools used for support, EOS High Interest Event statistics, and potential challenges expected in the future.

Syed Hasan

The 7 Year Evolution of EOS CA Support for Planning & Executing Risk Mitigation Maneuvers

This presentation will discuss the evolution of Collision Avoidance (CA) support for planning and executing Risk Mitigation Maneuvers (RMMs) for the Earth Observing System (EOS) Aqua, Aura, and Terra satellites within the seven-year period of January 2015 through December 2021. Several enhancements were implemented by the EOS team to expedite and improve the RMM planning and execution process, including updates to High Interest Event (HIE) analysis, maneuver preparation, maneuver ephemeris generation, conjunction event data screening, and maneuver commanding. As of 2022, these advancements allow the EOS team to plan and execute an RMM within 5 hours of identification with an accurate and low-risk solution. This represents a vast improvement from the 30 hours required to turn around an RMM back in 2015. In addition, the current process is substantially less error prone. Details of this progression and the specific aspects of each supporting component are explicated in the content of the presentation.

Syed Hasan