Daniel Oltrogge, COMSPOC; Jeff Cornelius, COMSPOC; Tim Glinski, LSAS Tec; David Vallado, COMSPOC Corporation; Alexander Ridgeway, AGI, An Ansys Company; Yosuke Yamamoto, LSAS Tec; Salvatore Alfano, COMSPOC; Joseph Chan, Intelsat S.A.; Charles Law, SES S.A.
Keywords: Maneuvers, collaborative SSA, data fusion, covariance realism, SSA, SDA, Space Data Association, Orbit Determination, Detection, Collision Analysis, Observation Association, COMSPOC, LSAS Tec, SSS, UMA, STK, ODTK, Maneuver Processing
Abstract:
This paper characterizes the significant SSA accuracy, timeliness, and safety degradations caused by maneuvers, maneuver uncertainties, and outdated orbit determination systems in both RPO and normal spacecraft operations. Then, practical approaches to address these degradations are explored, including (1) collaborative planned maneuver and observation sharing in a data lake model, (2) incorporation of commercial SSA observational data, (3) data fusion, and (4) orbit determination algorithms suited to rapid maneuver detection, characterization, calibration, and recovery.
Maneuvers are the lifeblood of orbit operations, constellation maintenance, orbit insertion, disposal, and achievement of mission. Just as the Wright brothers didn’t “achieve flight” until it was powered, being able to maneuver in space is essential for spaceflight operations and control. Yet for all the good that maneuvers do to orbit operations, maneuvers are the single most important driver and weakest link to achieving SSA accuracy, timeliness, covariance realism, and safety. Long-standing orbit and conjunction assessment products provided at no cost to spacecraft operators by the US government fail to adequately address both known and non-cooperative maneuvers. Spacecraft operators have been keenly aware of these SSA capability gaps for many years, even compelling several spacecraft operators to self-form and fund the Space Data Association as a stopgap measure to address these known maneuver deficiencies.
Relevant cases which demonstrate these SSA accuracy degradations are presented, including:
A summary of our forensic reconstruction of the Iridium Cosmos collision that identified an increase in collision probability by a whopping 41 orders of magnitude due to the presence of a single unknown station keeping maneuver.
Spacecraft of the Space Data Association that regularly have degraded orbits when operator or commercial SSA data is not incorporated.
Maneuvers in RPO-engaged spacecraft that may have errors in maneuver magnitude and/or direction, leading to unintended close approaches or collisions.
Delays in recovering from maneuvers of up to one week as legacy SSA systems struggle to fit two-body orbits through flight segments containing maneuvers.
Addressing these deficiencies will require a holistic, collaborative, and technically advanced approach, and fortunately there are high-TRL approaches available that we systematically explore in this paper to assess their benefits in addressing these challenges. In this paper, we explore the aggregate benefits of these approaches through the lens of the Space Data Association (SDA) contributions to the recent Department of Commerce (DOC) Pilot for Space Traffic Management (STM) conducted from 5 Dec 2022 to mid-February. The SDA’s effort consisted of generating fused orbital solutions for 100 selected Middle Earth Orbit (MEO) and Geostationary Earth Orbit (GEO) spacecraft, with over eighty five percent of those spacecraft enrolled or participating in the SDA’s Space Data Center. The SDA and its spacecraft operators employed a commercial SSA data and analytics provider to receive the operator’s planned maneuvers and observations in a data lake model and employ an sequential filter orbit determination to generate both smoothed (historical or reconstructed) and predictive (filter) ephemerides and covariances. To ensure that maneuvers were rapidly detected, characterized, and calibrated so that accurate solutions can be quickly recovered, this SDA-supplied product included a non-cooperative maneuver algorithm and associated optimization. Twenty seven of the selected hundred spacecraft had some form of independent high-accuracy positional source such as GNSS data, laser ranging, SBAS, or IGS positional measurements or “truth ephemerides.” While this level of data sharing from comprehensive data fusion presented some unique data exchange and fusion challenges, results for the ten commercial spacecraft operators involved in the study indicate the potential for huge SSA accuracy gains using a fused approach.
Date of Conference: September 19-22, 2023
Track: Space Domain Awareness