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Edward Semones

Publications and source records attributed to Edward Semones.

11 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS2023

Information and Best Practices Related to NASA Nuclear Flight Safety for Space Flights Involving Space Nuclear Systems

The purpose of this handbook is to facilitate a repeatable and robust process that promotes clear and effective interfaces between activities and stakeholders focused on meeting nuclear flight safety requirements for missions utilizing space nuclear systems (SNS), within the context of NASA’s broader nuclear-related activities and interfaces. NPR 8715.26, Nuclear Flight Safety, requires that the NASA project manager “incorporate nuclear flight safety considerations starting with program or project formulation through the point at which the SNS or other radioactive material no longer has the potential to affect Earth’s biosphere.” NASA’s use of SNS inherently involves partnering with other stakeholders to conduct a range of related activities that interface with nuclear flight safety. From a categorical perspective these include: (i) meeting the authorities and licensing requirements for possession and use of nuclear material, as governed by other Federal authorities; (ii) conducting National Environmental Policy Act (NEPA) activities for nuclear-enabled missions; (iii) meeting Federal nuclear launch authorization requirements; (iv) conducting radiological contingency planning activities, including those associated with international commitments; (v) performing risk communication and public outreach activities; and (vi) ensuring decommissioning and disposal strategies reflect National policies and interests. It is the intent of this handbook to promote an effective interface between nuclear flight safety and these interrelated categorical activities. In addition to activities undertaken with partnering agencies, there are individual nuclear-related activities and programs that have a nexus to nuclear flight safety, and these include: (i) applicable NASA Standing Review Boards; (ii) the US Department of Energy nuclear safety activities conducted in partnership with NASA under Memoranda of Understanding; (iii) the Department of Defense’s Range Safety activities; (iv) NASA’s general involvement in interagency and international dialogues regarding nuclear safety; (v) the NASA-administered Interagency Nuclear Safety Review Board; (vi) NASA’s program and project governance activities and nuclear-specific Technical Discipline Team activities under the Office of the Chief Engineer; and others. It is the intent of this handbook to promote effective leveraging of these additional interrelated organizational activities, as appropriate.

Donald Helton↗
NASA NTRS2022

Review of Solar Energetic Particle Models

Solar Energetic Particle (SEP) events are interesting from a scientific perspective as they are the product of a broad set of physical processes from the corona out through the extent of the heliosphere, and provide insight into processes of particle acceleration and transport that are widely applicable in astrophysics. From the operations perspective, SEP events pose a radiation hazard for aviation, electronics in space, and human space exploration, in particular for missions outside of the Earth’s protective magnetosphere including to the Moon and Mars. Thus, it is critical to improve the scientific understanding of SEP events and use this understanding to develop and improve SEP forecasting capabilities to support operations. Many SEP models exist or are in development using a wide variety of approaches and with differing goals. These include computationally intensive physics-based models, fast and light empirical models, machine learning-based models, and mixed-model approaches. The aim of this paper is to summarize all of the SEP models currently developed in the scientific community, including a description of model approach, inputs and outputs, free parameters, and any published validations or comparisons with data.

Kathryn Whitman↗
NASA NTRS2022

Evaluation of Multiple Methods for Calculating Gray Equivalent

The assessment of different algorithms to determine the Gray-Equivalent as defined in NASA-STD-3001 from a source of space radiation has been evaluated in this paper. The Gray-Equivalent applies an RBE (Relative Biological Effectiveness) to the dose seen at the organ of interest in a human phantom. The current design basis solar particle event was used in the assessments along with the August 1972 event modeled by J.H. King and with idealized spheres and two vehicle designs. Three different algorithms were used and compared. One of the algorithms was the current OLTARIS algorithm. This algorithm is astronaut orientation averaged, which is not what happens in a storm shelter during a solar particle event. Two other algorithms were proposed to eliminate this issue. It is clear that either algorithm will be adequate to satisfy NASA-STD-3001 requirements. This work recommends the algorithm which applies the RBEs to the phantom points instead of at the surface of the phantom as with the current OLTARIS algorithm.

Gray Equivalent↗
NASA NTRS2021

Comparison of Health and Performance Risk for Accelerated Mars Mission Scenarios

This document details the results for a quantitative estimate of the difference in human health and performance risk that crews would face for two hypothetical variations on Mars mission scenarios: an Accelerated Mars Mission (AMM) and a Standard Mars Mission(SMM).NASA goals for Mars mission concepts, duration, and tasks have varied over the years. While neither of the cases considered here are likely to accurately represent the initial mission to Mars, the exercise of evaluating significant differences in mission duration from an astronaut health perspective can provide bounding insight to the level of risk that is likely to be encountered in an eventual Mars mission. Medical Probabilistic Risk Assessment using the Integrated Medical Model (IMM)(1–3)and the NASA Space Radiation Cancer Risk Model (NSCR)(4,5) are used here to help mission planners gain the best insight currently available into the expected magnitude of impacts to astronaut health when undertaking a Mars mission. These impacts occur both in-mission as well as in the long-term health of the astronauts post-mission. These evaluations are currently the best available modeling estimates to characterize and bound the health risks in a proposed mission domain where humans have no experience.

Erik Antonsen↗
NASA NTRS2020

Machine Learning in Heliophysics and space weather forecasting: a white paper of finding and recommendations

The authors of this white paper met on 16-17 January 2020 at the New Jersey Institute of Technology,Newark, NJ, for a 2-day workshop that brought together a group of heliophysicists, data providers,expert modelers, and computer/data scientists. Their objective was to discuss critical developments and prospects of the application of machine and/or deep learning techniques for data analysis, modeling and forecasting in Heliophysics, and to shape a strategy for further developments in the field. The workshop combined a set of plenary sessions featuring invited introductory talks interleaved with a set of open discussion sessions. The outcome of the discussion is encapsulated in this white paper that also features a top-level list of recommendations agreed by participants

HSR↗
NASA NTRSDate not supplied

SPHINX: A Generalized Tool for Solar Energetic Particle Model Validation

The Integrated Solar Energetic Proton Alert/Warning (ISEP) project was established to aid in the transition of SEP models from the research realm to operational use. This project is a collaboration between the NASA Community Coordinated Model Center (CCMC), the NASA Moon to Mars Space Weather Analysis Office (M2M) and the NASA Space Radiation Analysis Group (SRAG). Through ISEP, the SEP Scoreboards (Intensity, Probability, and All Clear) were developed to visualize real time forecasts from SEP models for use in SRAG operations. To accomplish this, SRAG, CCMC, and M2M work closely with modelers on model development, CCMC works on Scoreboard implementation, and M2M provides human-in-the-loop space weather analysis and ensures that models run in real time.

space weather↗
NASA NTRSDate not supplied

Impact of the May 2024 Gannon Storm on Low Earth Orbit Dosimetric Quantities: Comparisons of the NAIRAS Model -Real Time and Re-analysis- with ISS Data

The solar storm of May 2024, the Gannon storm, led to a display of aurora over the globe. One of the less known effects of that storm is on the radiation doses in low-Earth orbit: it first led to a Forbush decrease in dose rates and then to a Solar Energetic Particle (SEP) event that increased the total dose suffered near the international space station. The Nowcast of Aerospace Ionizing RAdiation System (NAIRAS) model predicts dosimetric and radiative flux quantities for assessing human radiation exposure levels and radiation effects on flight electronic systems from the surface of the Earth to deep space. It runs in near-real-time at the CCMC, but also has a run-on-request that allows for a more precise computation thanks to carefully processed data. NAIRAS was able to compute the effects of the Gannon storm at the ISS in real-time and provide ideas of the doses encountered by the astronauts and the experiments in and outside of the station. In this work, we show the simulations of the doses encountered during the storm and compare them with several measurements at the ISS. This work shows the capabilities of NAIRAS to address the problem of the SEP events at low Earth orbit and its real-time capabilities.

Guillaume Gronoff↗
NASA NTRSDate not supplied

Planning for a Large Space Weather Event: Preparation for and Lessons Learned from the 2024 Space Weather Interagency Tabletop Exercise

On May 8-9 2024, the Space Radiation Analysis Group (SRAG) at NASA/Johnson Space Center participated in a joint exercise with DoD, FEMA, OSTP, DOE and other agencies to assess their ability to respond to a large hypothetical space weather event. SRAG is a uniquely skilled group of scientists and engineers tasked with mitigating impacts of radiation exposure to the astronaut crew aboard the International Space Station and upcoming missions beyond Low Earth Orbit (LEO). In meeting this objective, the team has developed expertise in both modeling the impacts of an enhanced space environment and in the real-time operational support of the Flight Control Team when assessing a response to the environment. Several members of SRAG worked with the Tabletop Exercise (TTX) planners to define a realistic large event and to model the resulting radiation exposure on an Artemis crew. SRAG members participating in the TTX were blinded to the results of this analysis. As the event unfolded during the TTX, SRAG provided their assessment of the likely impact on the crew and recommendations for crew actions. During the exercise, the team tracked lessons learned for their own planning, currently in work, for Artemis-II and subsequent missions.

Janet Barzilla↗