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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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2-D Pc, 3D-Nc, and BFMC Pc Calculations for Single and Repeating Conjunctions
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NASA Spacecraft Conjunction Assessment and Collision Avoidance Best Practices Handbook
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What's Up in the Sky: Conjunctions and Calendars
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Conjunction Assessment Risk Analysis for Smallsats
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Satellite Conjunction Assessment Risk Analysis for “Dilution Region” Events: Issues and Operational Approaches
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NASA Spacecraft Conjunction Assessment and Collision Avoidance Best Practices: The History, Evolution and Opportunities.
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Conjunction Assessment: NASA Best Practices and Lessons Learned
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Conjunction Assessment at NASA
The number of objects in orbit is growing exponentially The space environment today is very different from a decade ago and continues to evolve very rapidly - Historically, space operations were domain of large governmental entities. - Commercial space operators are becoming commonplace and have different business models than government actors - CubeSats are cost effective and accessible for everyone, even down to elementary schools - Challenge in educating new space actors on best practices and availability of data and tools Technology enabling this access has rapidly evolved, while no regulatory framework has been established to ensure that space can be used safely by all.
Conjunction Assessment Risk Analysis
Materials for short course. This briefing from NASA is one segment of a larger 3-day course being presented by multiple entities.
Satellite Conjunction Assessment: NASA Best Practices and Lessons Learned
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Conjunction Assessment and Deconfliction Paradigm for Co-located Satellite Constellations with On-Spacecraft “Autonomous” Flight Dynamics Control
Constellations that employ highly-automated satellite flight dynamics can operate safely from a collision avoidance (CA) perspective using current CA screening technology and communication paradigms—except when in proximity to other highly-automated constellations: there is no existing arrangement and concept of operations to allow the low-latency CA screenings, exchange of information, and assignment/acceptance of mitigation responsibility that co-location of highly-automated constellations requires. However, the serendipitous co-location of the NASA Starling mission—an autonomously-controlled technology demonstration constellation—and the SpaceX Starlink constellation has presented an opportunity (indeed, a requirement) to develop and build out a solution for safe operations of two (or more) co-located, highly-automated satellite constellations. Such a solution has been designed and constructed, including the required ground node; and it will be exercised as a dedicated, in-flight safety experiment between the two constellations from January to September 2024. Lessons learned from this experiment are expected to feed the design of the US Department of Commerce’s Tracking Control System for Space (TraCSS) space traffic coordination solution.
Conjunction Assessment and Deconfliction Paradigm for Co-located Satellite Constellations with On-Spacecraft “Autonomous” Flight Dynamics Control
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Conjunction Assessment Special Topics
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Satellite Conjunction Assessment Best Practices
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Conjunction Sensitivity to Atmospheric Density Modeling
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Synchrotron-based X-ray Fluorescence Microscopy in Conjunction with Nanoindentation to Study Molecular-Scale Interactions of Phenol-Formaldehyde in Wood Cell Walls
Understanding and controlling molecular-scale interactions between adhesives and wood polymers are critical to accelerate the development of improved adhesives for advanced wood-based materials. The submicrometer resolution of synchrotron-based X-ray fluorescence microscopy (XFM) was found capable of mapping and quantifying infiltration of Br-labeled phenolformaldehyde (BrPF) into wood cell walls. Cell wall infiltration of five BrPF adhesives with different average molecular weights (MWs) was mapped. Nanoindentation on the same cell walls was performed to assess the effects of BrPF infiltration on cell wall hygromechanical properties. For the same amount of weight uptake, lower MW BrPF adhesives were found to be more effective at decreasing moisture-induced mechanical softening. This greater effectiveness of lower MW phenolic adhesives likely resulted from their ability to more intimately associate with water sorption sites in the wood polymers. Evidence also suggests that a BrPF interpenetrating polymer network (IPN) formed within the wood polymers, which might also decrease moisture sorption by mechanically restraining wood polymers during swelling.