Modeling and Testing of Wireless Diamond Radiation Detector Prototype for Dry Spent Fuel Canister Monitoring.
Abstract not provided.
McAdams, Daniel R.↗
SEARCH · Engineering Papers
Results for “Radiation Monitoring”
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.
Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.
Radiation transport modeling and assessment to better predict radiation exposure, dose, and toxicological effects to human organs on long duration space flights
NASA is very interested in improving its ability to monitor and forecast the radiation levels that pose a health risk to space-walking astronauts as they construct the International Space Station and astronauts that will participate in long-term and deep-space missions. Human exploratory missions to the moon and Mars within the next quarter century, will expose crews to transient radiation from solar particle events which include high-energy galactic cosmic rays and high-energy protons. Because the radiation levels in space are high and solar activity is presently unpredictable, adequate shielding is needed to minimize the deleterious health effects of exposure to radiation. Today, numerous models have been developed and used to predict radiation exposure. Such a model is the Space Environment Information Systems (SPENVIS) modeling program, developed by the Belgian Institute for Space Aeronautics. SPENVIS, which has been assessed to be an excellent tool in characterizing the radiation environment for microelectronics and investigating orbital debris, is being evaluated for its usefulness with determining the dose and dose-equivalent for human exposure. Thus far. the calculations for dose-depth relations under varying shielding conditions have been in agreement with calculations done using HZETRN and PDOSE, which are well-known and widely used models for characterizing the environments for human exploratory missions. There is disagreement when assessing the impact of secondary radiation particles since SPENVIS does a crude estimation of the secondary radiation particles when calculating LET versus Flux. SPENVIS was used to model dose-depth relations for the blood-forming organs. Radiation sickness and cancer are life-threatening consequences resulting from radiation exposure. In space. exposure to radiation generally includes all of the critical organs. Biological and toxicological impacts have been included for discussion along with alternative risk mitigation methods--shielding and anti-carcinogens. c 2001. Elsevier Science Ltd. All rights reserved.
STS-91 Shuttle Project↗
Gamma ray slush hydrogen monitor
Mass attenuation for 109Cd radiation have been measured in mixtures of phases and in single phases of five chemical compounds. As anticipated, the mass attenuation coefficients are independent of the phases of the test chemicals. It is recommended that a slush hydrogen monitoring system based on low energy gamma ray attenuation be developed for utilization aboard the NASP.
Singh, Jag J.↗
ISEP: A Joint SRAG/CCMC Collaboration to Improve Mitigation of Space Weather Effects on Crew Health in the Exo-LEO Era
The Space Radiation Analysis Group (SRAG) at Johnson Space Center (JSC) is tasked with monitoring changes to space weather and mitigating any resultant impacts to crew health and safety. As human spaceflight goals extend from Low-Earth Orbit (LEO) missions like the International Space Station (ISS) to the moon, Mars and beyond, SRAG will need to update their current approach for crew monitoring of and protection from radiation exposure due to energetic Solar Particle Events (ESPEs). Challenges faced in planning exo-LEO missions include the lack of protection from the Earth’s geomagnetic field employed by the ISS in addition to limited communication capability between the crew and the ground. In the event of an ESPE, the current ISS trajectory ensures that the vehicle is only traveling through fields of higher radiation exposure for a brief period of time; the Earth’s geomagnetic field prevents the penetration of the high-energy particles of concern throughout the majority of the orbit. Exo-LEO missions, on the other hand, require that the vehicle travel through free space, exposing vehicle and crew to the full impact of the ESPE. NASA has combined multiple approaches to resolve this radiation exposure issue. New vehicles are designed to take advantage of advances in particle transport modeling capabilities and shielding technology, allowing redistribution of mass throughout the vehicle to areas of thinner shielding when the energetic particle flux has increased to levels of concern. Although vehicle shielding is an important aspect of radiation exposure protection, there is a continued requirement to monitor and predict the space weather environment. To this end, SRAG maintains a console position in Mission Control with 24/7 mission support capability. In the event of increased solar activity, SRAG collaborates with the Flight Control Team (FCT) to determine if crew action (i.e., shelter) is required. During any increase in solar activity, the FCT needs three pieces of information to effectively decide the crew response in light of other required mission tasks: if an event (ESPE) will occur, how ‘intense’ an observed event will be, and how long will an observed event will last. An ideal alert system limits false alarms, therefore causing the crew to take action unnecessarily, without ignoring events that pose a hazard to the crew. SRAG’s current operational concept for ISS missions focuses on short-term forecasts, best described as ‘now-casting’. Console operators are in daily communication with the Space Weather Prediction Center (SWPC) for situational awareness purposes. When conditions exist that may lead to increased solar activity, operators receive notifications from SWPC. In the case of a well-connected ESPE, the console operator may only have on the order of minutes to several hours to notify the FCT of the event and provide a recommendation for crew action. As NASA shifts to exo-LEO missions, the increased time in free space as well as the reduced ability to communicate with the crew will force a transition in crew protection strategy that emphasizes improvments to both the accuracy and the lead time in forecasting capabilities.
Barzilla, Janet E.↗
Cell Radiation Experiment System
The cell radiation experiment system (CRES) is a perfused-cell culture apparatus, within which cells from humans or other animals can (1) be maintained in homeostasis while (2) being exposed to ionizing radiation during controlled intervals and (3) being monitored to determine the effects of radiation and the repair of radiation damage. The CRES can be used, for example, to determine effects of drug, radiation, and combined drug and radiation treatments on both normal and tumor cells. The CRES can also be used to analyze the effects of radiosensitive or radioprotectant drugs on cells subjected to radiation. The knowledge gained by use of the CRES is expected to contribute to the development of better cancer treatments and of better protection for astronauts, medical-equipment operators, and nuclear-power-plant workers, and others exposed frequently to ionizing radiation.
Morrison, Dennis R.↗
Correlations and linkages between the sun and the earth's atmosphere: Needed measurements and observations
A summary of needed measurements and observations is reported to identify the sequence of processes leading from change in solar input to change in tropospheric circulation and weather. Changes in the solar electromagnetic radiation have to be carefully monitored since variations over the solar cycle are small (less than one percent). It is suggested that changes in the ionization at the Pfotzer maximum could influence the formation of thunderstorms by changing the electric potential gradient. This could be checked by measuring the global atmospheric electric field. As an example of spacecraft observations, a worldwide distribution plot of nocturnal thunderstorms compiled from OSO-5 data shown; no obvious correlation with solar data had been found, but the time span of the data is rather limited and more sophisticated observation techniques could be used. Continuous and careful monitoring is recommended of the input of electromagnetic and particle radiation into the earth's atmosphere ozone distributions in the region above 30 km, and wind systems in the mesosphere and lower thermosphere. In addition, special phenomena suspected to be important in the causal chain, such as cirrus cloud formation at high latitudes and thunderstorm activity, should be monitored on a global basis.
Kellogg, W. W.↗
Space radiation studies
Two Active Radiation Dosimeters (ARD's) flown on Spacelab 1, performed without fault and were returned to Space Science Laboratory, MSFC for recalibration. During the flight, performance was monitored at the Huntsville Operations Center (HOSC). Despite some problems with the Shuttle data system handling the verification flight instrumentation (VFI), it was established that the ARD's were operating normally. Postflight calibrations of both units determined that sensitivities were essentially unchanged from preflight values. Flight tapes were received for approx. 60 percent of the flight and it appears that this is the total available. The data was analyzed in collaboration with Space Science Laboratory, MSFC. Also, the Nuclear Radiation Monitor (NRM) was assembled and tested at MSFC. Support was rendered in the areas of materials control and parts were supplied for the supplementary heaters, dome gas-venting device and photomultiplier tube housing. Performance characteristics of some flight-space photomultipliers were measured. The NRM was flown on a balloon-borne test flight and subsequently performed without fault on Spacelab-2. This data was analyzed and published.
Source record↗
Space radiation studies for the reporting period, June 1983 - July 1984
Two Active Radiation Dosimeters (ARD's) flown on Spacelab 1, performed without fault and were returned to Space Science Laboratory, MSFC for recalibration. During the flight in December 1983, performance was monitored at the Huntsville Operations Center (HOSC). Despite some problems with the Shuttle data system handling the VFI, it could be established that the ARD's were operating normally. Postflight calibrations of both units determined that sensitivities were essentially unchanged from preflight values. Flight tapes were received for approximately 60% of the flight and it appears that this is the total available. The next phase of effort will involve close collaboration with Space Science Laboratory, MSFC, in the analysis of this data. The Nuclear Radiation Monitor (NRM) was under assembly and testing at MSFC. Support was rendered in the areas of materials control and parts were supplied for the supplementary heaters, dome gas-venting device and photomultiplier tube housing. Performance characteristics of some flight-space photomultipliers were measured.
Source record↗
Introduction to Radiative Transfer Theory and Models (Optical Domain)
Atmospheric correction of earth observation data for environmental monitoring theory and best practices. radiative transfer,atmospheric transmission,albedo
albedo↗
P0004-1 quick look
The P0004-1 'Seeds in Space' experiment consisted of six sealed aluminum canisters which contained tomato seeds and a variety of other seeds for the study of space radiation effects on the seeds. The seeds were contained in cloth bags. Interspersed among the bags of seeds were ten dosimeter packets to monitor the accumulated ionizing radiation exposure of the seeds. In addition to the ten flight dosimeter packets, four ground control packets and one ground movement packet were also included as part of the experiment. The P0004-1 experiment was mounted on the F2 tray, near the trailing edge of the LDEF orbiter. The results indicate that the neutron fluences were higher in the P0004 canisters than in that of P0006. The difference was much greater for thermal neutrons than resonance neutrons. This is consistent with shielding.
Source record↗
Radiation-induced insulator discharge pulses in the CRRES Internal Discharge Monitor satellite experiment
The Internal Discharge Monitor (IDM) is designed to observe electrical pulses from common electrical insulators in space service. The IDM is flying on the Combined Release and Radiation Effects Satellite (CRRES). The sixteen insulator samples include G10 circuit boards, FR4 and PTFE fiberglass circuit boards, FEP Teflon, alumina, and wires with common insulations. The samples are fully enclosed, mutually isolated, and space radiation penetrates 0.02 cm of aluminum before striking the samples. The IDM results indicate the rate at which insulator pulses occur. Pulsing began on the seventh orbit. The maximum pulse rate occurred near orbit 600 when over 50 pulses occurred. The average pulse rate is approximately two per orbit, but nearly half of the first 600 orbits experienced no pulses. The pulse rate per unit flux of high energy electrons has not changed dramatically over the first ten months in space. These pulse rates are in agreement with laboratory experience on shorter time scales. Several of the samples have never pulsed. IDM pulses are the seeds of larger satellite electrical anomalies. The pulse rates are compared with space radiation intensities, L shell location, and spectral distributions from the radiation spectrometers on CRRES.
Frederickson, A. R.↗
Radiation plan for the Apollo lunar mission.
Radiation protection plan for Apollo lunar mission based on real time monitoring of solar activity and radiation in spacecraft
Lopez, M. D.↗
Long-term Solar Irradiance Variability: 1984-1989 Observations
Long-term variability in the total solar irradiance has been observed in the Earth Radiation Budget Experiment (ERBE) solar monitor measurements. The monitors have been used to measure the irradiance from the Earth Radiation Budget Satellite (ERBS) and the National Oceanic and Atmospheric Administration NOAA-9 and NOAA-10 spacecraft platforms since October 25, 1984, January 23, 1985, and October 22, 1986, respectively. Before September 1986, the ERBS irradiance values were found to be decreasing -0.03 percent per year. This period was marked by decreasing solar magnetic activity. Between September 1986 and mid-1989, the irradiance values increased approximately 0.1 percent. The latter period was marked by increasing solar activity which was associated with the initiations of the sunspot cycle number 22 and of a new 22-year Hale solar magnetic cycle. Therefore, long-term solar-irradiance variability appears to be correlated directly with solar activity. The maximum smoothed sunspot number occurred during September 1989, according to the Sunspot Index Data Center. Therefore, the recent irradiance increasing trend should disappear during early 1990 and change into a decreasing trend if the observed irradiance variability is correlated more so with the 11-year sunspot cycle than the 22-year Hale cycle. The ERBE irradiance values are presented and compared with sunspot activity for the 1984 to 1989 period. The ERBE values are compared with those available from the Nimbus-7 and Solar Maximum Mission spacecraft experiments.
Lee, Robert B., III↗
ISS Radiator Face Sheet Anomaly Investigation and Return to Function
Maintaining sufficient heat rejection on the International Space Station (ISS) is critical to the function of the Low-Earth Orbit station. The External Active Thermal Control System (EATCS) rejects the excess heat generated by the US On-Orbit Segment (USOS) modules. The system uses single-phase liquid ammonia to collect the heat and reject it to six radiators (three on the Starboard side, three on the Port side). Each radiator is made up of eight panels. In September 2008, imagery of the Starboard radiators was conducted and showed one of the panels’ face sheets had peeled up from the internal honeycomb core structure. Out of an abundance of caution, the radiator was isolated from the rest of the EATCS and the ammonia was vented to space. Since the radiator was vented, periodic imagery of all radiator panels was taken to monitor any changes in the face sheet and inspect for other radiator anomalies. In January 2025, after years of trending and inspections, the radiator was reintegrated into the system to increase heat rejection capabilities. This paper will document the multi-year investigation that took place to determine root cause and mitigations implemented to reduce risk to the system. A summary of the data since the investigation will show rationale for reintegrating the radiator even with the damaged panel. The goal of the paper is to document the investigation for historical purposes and provide future programs with findings discovered during the investigation.
Aaron Rodriguez↗
ISS Radiator Face Sheet Anomaly Investigation and Return to Function
Maintaining sufficient heat rejection on the International Space Station (ISS) is critical to the function of the Low-Earth Orbit station. The External Active Thermal Control System (EATCS) rejects the excess heat generated by the US On-Orbit Segment (USOS) modules. The system uses single-phase liquid ammonia to collect the heat and reject it to six radiators (three on the Starboard side, three on the Port side). Each radiator is made up of eight panels. In September 2008, imagery of the Starboard radiators was conducted and showed one of the panels’ face sheets had peeled up from the internal honeycomb core structure. Out of an abundance of caution, the radiator was isolated from the rest of the EATCS and the ammonia was vented to space. Since the radiator was vented, periodic imagery of all radiator panels was taken to monitor any changes in the face sheet and inspect for other radiator anomalies. In January 2025, after years of trending and inspections, the radiator was reintegrated into the system to increase heat rejection capabilities. This paper will document the multi-year investigation that took place to determine root cause and mitigations implemented to reduce risk to the system. A summary of the data since the investigation will show rationale for reintegrating the radiator even with the damaged panel. The goal of the paper is to document the investigation for historical purposes and provide future programs with findings discovered during the investigation.
Aaron Rodriguez↗
Total solar irradiance values determined using Earth Radiation Budget Experiment (ERBE) radiometers
During the October 1984 through January 1988 period, the ERBE solar monitors on the NASA Earth Radiation Satellite and on the National Oceanic and Atmospheric Administration NOAA 9 and NOAA 10 spacecraft were used to obtain mean total solar irradiance values of 1365, 1365, and 1363 W/sq m, respectively. Secular variations in the solar irradiance have been observed, and they appear to be correlated with solar activity.
Lee, Robert B., III↗
Beta Absorption Mass Monitoring of Particulates - A Review
The theory and application of beta-radiation absorption for the measurement and monitoring of airborne particulates are discussed. The use of this technique, both for source testing and for ambient air quality monitoring is reviewed. Various particle collection methods used in conjunction with beta absorption sensing configurations are considered. State of the art and current developments of instrumentation approaches for the automated measurement of mass concentration and size distribution of aerosols by beta absorption are discussed. Methods for electronic signal processing and recording are presented. The Beta absorption technique appears as a powerful tool for the unattended measurement of the mass of particulate pollution, compatible with telemetry and central data processing methods.
Lilienfeld, Pedro↗
Charged Particle Environments in Earth's Magnetosphere and their Effects on Space System
This slide presentation reviews information on space radiation environments important to magnetospheric missions including trapped radiation, solar particle events, cosmic rays, and solar winds. It also includes information about ion penetration of the magnetosphere, galactic cosmic rays, solar particle environments, CRRES internal discharge monitor, surface charging and radiation effects.
Minow, Joseph I.↗