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Space Weather Impacts to Conjunction Assessment: A NASA Robotic Orbital Safety PerspectiveNational Aeronautics and Space Administration (NASA) recognizes the risk of on-orbit collisions from other satellites and debris objects and has instituted a process to identify and react to close approaches. The charter of the NASA Robotic Conjunction Assessment Risk Analysis (CARA) task is to protect NASA robotic (unmanned) assets from threats posed by other space objects. Monitoring for potential collisions requires formulating close-approach predictions a week or more in the future to determine analyze, and respond to orbital conjunction events of interest. These predictions require propagation of the latest state vector and covariance assuming a predicted atmospheric density and ballistic coefficient. Any differences between the predicted drag used for propagation and the actual drag experienced by the space objects can potentially affect the conjunction event. Therefore, the space environment itself, in particular how space weather impacts atmospheric drag, is an essential element to understand in order effectively to assess the risk of conjunction events. The focus of this research is to develop a better understanding of the impact of space weather on conjunction assessment activities: both accurately determining the current risk and assessing how that risk may change under dynamic space weather conditions. We are engaged in a data-- ]mining exercise to corroborate whether or not observed changes in a conjunction event's dynamics appear consistent with space weather changes and are interested in developing a framework to respond appropriately to uncertainty in predicted space weather. In particular, we use historical conjunction event data products to search for dynamical effects on satellite orbits from changing atmospheric drag. Increased drag is expected to lower the satellite specific energy and will result in the satellite's being 'later' than expected, which can affect satellite conjunctions in a number of ways depending on the two satellites' orbits and the geometry of the conjunction. These satellite time offsets can form the basis of a new technique under development to determine whether space weather perturbations, such as coronal mass ejections, are likely to increase, decrease, or have a neutral effect on the collision risk due to a particular close approach.
Document ID
20130009663
Acquisition Source
Goddard Space Flight Center
Document Type
Presentation
Authors
Ghrist, Richard
(AI Solutions, Inc. Lanham, MD, United States)
Ghrist, Richard
(AI Solutions, Inc. Lanham, MD, United States)
DeHart, Russel
(AI Solutions, Inc. Lanham, MD, United States)
Newman, Lauri
(NASA Goddard Space Flight Center Greenbelt, MD, United States)
Date Acquired
August 27, 2013
Publication Date
January 29, 2013
Subject Category
Space Transportation And Safety
Report/Patent Number
GSFC.OVPR.7520.2013
Meeting Information
Meeting: Integrated Modeling of Perturbations in Atmospheres for Conjunction Tracking (IMPACT)
Location: Santa Fe, NM
Country: United States
Start Date: January 29, 2013
End Date: January 31, 2013
Sponsors: Los Alamos National Lab.
Distribution Limits
Public
Copyright
Public Use Permitted.
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