Kelso, T.S. and Kuciapinski, Kevin, "Understanding and Mitigating Data Limitations for Conjunction Assessments," presented at 76th International Astronautical Congress, Sydney, Australia, 2025 Sep 30.
Increasing orbital congestion, with satellites that maneuver more frequently, has uncovered serious weaknesses in current conjunction assessment (CA) processes that pose increased risk to safety of flight, if not fully understood.
Historically, space operators have accepted, used, and trusted orbital data and conjunction assessment products produced by the US government, without question, and many users are left with the false impression that they have it all under control.
Yet these products can be readily shown to have serious flaws by using more reliable orbital data products like satellite operator ephemerides or other high-precision orbital data products. It is imperative that operators understand how to easily use existing tools to detect when these flaws are present and apply available data to quickly remedy them.
There are also flaws in standard data products, like the Conjunction Data Message (CDM), that undermine the ability to screen with these more reliable orbital data products because they actually mask the effects of maneuvers due to improper force modeling. Obviously, this has serious implications for constellations, like Starlink, where satellites are maneuvering all the time.
The good news is that these existing solutions are already available on CelesTrak and can quickly help operators not only identify bad data but actually provide data to resolve problems like missed maneuvers and cross-tagging.
This paper will examine the conditions and faulty assumptions that lead to this situation and show how the tools to address them were developed and how they can be used by SSA providers to improve overall SSA. It will also show how a simple—and obvious—change to the CDM can remove a fundamental flaw. Finally, this paper will address common misperceptions about how other data products, such as SP (Special Perturbations) or the new XP data type can mislead operators into a false sense of security, when they also suffer the same fundamental issues as GP (General Perturbations) data when working with maneuvering satellites.
Ultimately, it is hoped that a more complete understanding of these issues and remedies will encourage satellite operators and SSA providers to work together more closely to apply these lessons-learned and motivate others to freely and transparently share their data to ensure we are best prepared to do what is necessary to protect safety of flight and protect the near-Earth orbital environment.
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