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The goal of this presentation is to help the Teachers in Space candidates understand Space Weather and its implications for flight.
No abstract available
The Atmosphere-Space Transition Region Explorer (ASTRE) is a mission concept designed to carry out an unprecedented study of the interaction between the Earth’s atmosphere and the ionized gases of space within the atmosphere-space transition region. By gathering direct measurements of the coupling of ion and neutral gases in this region, ASTRE provides the critical missing link in our knowledge of the transfer, dissipation, and regulation of energy and momentum between the sun and the upper atmosphere. ASTRE provides the first detailed, systematic investigation of this important unexplored region, vastly improves and constrains models of the upper atmosphere, and fills a critical gap in our understanding of how the coupled lower ionosphere/upper atmosphere “works” as a system. To achieve its science objectives, ASTRE gathers accurate measurements of plasma and neutral gases, electric and magnetic fields, and energetic particles using well-proven, in situ instruments with excellent flight heritage. Furthermore, as described herein, all the instruments have been designed to perform well in the low perigee environment, including altitudes of 150 km and lower. ASTRE utilizes a three-axis stabilized satellite that uses on-board propulsion to carry out systematic, low perigee measurements at high latitudes. The satellite design incorporates a “form follows function” approach with a cylindrical shape and conductive body-mounted solar arrays to minimize drag and perturbations to the space environment. Atomic-oxygen resistant materials are utilized and a passive thermal design with heat pipes and radiator panels minimizes the impact of aero-heating. ASTRE launches into a 250 km × 1500 km elliptical insertion orbit with an inclination of 83°. Perigee precesses from its highest northern latitude to its highest southern latitude every ~60 days. Hydrazine propulsion provides over 2000 orbits with perigee below 200 km, with a significant fraction as low as 150 km, during high latitude, two-week campaigns when perigee precesses to either the northern or southern high latitude region. At mid and low latitudes, the perigee is near 225 km. Because very conservative assumptions were made with respect to the orbital analysis and drag, including continuous 3-sigma “worst-case” solar flux and atmospheric density, when additional propellant is included (accommodated in the current design) and some of the stringent assumptions are relaxed, the ASTRE mission described herein may be expected to include repeated excursions to altitudes of ~130 km or even lower. This paper presents an overview of the ASTRE mission, its science motivation, and objectives. It includes a discussion of the science-driven requirements and traceability, followed by a “proof-of concept” implementation that includes notional instruments and a straightforward spacecraft design. Three key points are demonstrated: 1) There is a critical knowledge gap in the high latitude, atmosphere-space transition region below 250 km; 2) The instrument and measurement techniques needed to obtain the ASTRE measurements are well-proven and function well in the low-altitude environment; and 3) A mature spacecraft design, flight dynamics analysis, and concept of operations have been developed that demonstrate that the ASTRE mission can be achieved in a straightforward manner using current technologies.
Space cabin atmospheres - physical and physiological variables
The progress on developing models of the radiation environment since the 1960s is reviewed with emphasis on models that can be applied to predicting the performance of microelectronics used in spacecraft and instruments. Space, atmospheric, and ground environments are included. It is shown that models must be adapted continually to account for increased understanding of the dynamics of the radiation environment and the changes in microelectronics technology. The IEEE Nuclear and Space Radiation Effects Conference is a vital forum to report model progress to the radiation effects research community.
This presentation is an update from the 2011 and 2012 talks given to Teachers in Space. These slides include some recent space weather issues that are hot topics, including the adding our USEWX and USEWX partners, and information relevant to GSFC researchers.
The January 2022 Hunga Tonga–Hunga Ha’apai eruption was one of the most explosive volcanic events of the modern era, producing a vertical plume that peaked more than 50 km above the Earth. The initial explosion and subsequent plume triggered atmospheric waves that propagated around the world multiple times. A global-scale wave response of this magnitude from a single source has not previously been observed. Here we show the details of this response, using a comprehensive set of satellite and ground-based observations to quantify it from surface to ionosphere. A broad spectrum of waves was triggered by the initial explosion, including Lamb waves propagating at phase speeds of 318.2 ± 6 m s^(−1) at surface level and between 308 ± 5 to 319 ± 4 m s^(−1) in the stratosphere, and gravity waves propagating at 238 ± 3 to 269 ± 3 m s^(−1) in the stratosphere. Gravity waves at sub-ionospheric heights have not previously been observed propagating at this speed or over the whole Earth from a single source. Latent heat release from the plume remained the most significant individual gravity wave source worldwide for more than 12 h, producing circular wavefronts visible across the Pacific basin in satellite observations. A single source dominating such a large region is also unique in the observational record. The Hunga Tonga eruption represents a key natural experiment in how the atmosphere responds to a sudden point-source-driven state change, which will be of use for improving weather and climate models.
Space-faring crews must have safe breathing air throughout their missions to ensure adequate performance and good health. Toxicological assessment of air quality depends on the standards that define acceptable air quality, measurements of pollutant levels during the flight, and reports from the crew on their in-flight perceptions of air quality. Air samples from ISS flight 2A showed that contaminants in the Zarya module were at higher concentrations than the Unity module. At the crew's first entry, the amount of non-methane volatile organic compounds (NMVOCs) in Zarya was 23 Mg/cubic meter, whereas in the amount of NMVOCs in Unity was 5.3 mg/cubic meter. Approximately 26 hours later at egress from the modules, the NMVOCs were comparable indicating good mixing of the atmospheres. The 2A crew reported no adverse health effects related to air pollution during their flight. Ingress air samples from 2A.1, which was flown more than 5 months after 2A, again showed that the Zarya had accumulated more unscrubbed pollutants than Unity. The NMVOCs in Unity were 3.5 mg/cubic meter, whereas the were 20 mg/cubic meter in Zarya. After almost 80 hours of ISS operations, the NMVOCs were 7.5 and 12 mg/cubic meter in Unity and Zarya, respectively. This suggests that the atmospheres in the modules were not mixing very well. The 2A.1 crew felt that the air quality in Zarya deteriorated when they were working in a group at close quarters, when the panels had been removed, and after they had worked in an area for some time. The weight of evidence suggests that human metabolic products (carbon dioxide, water vapor, heat) were not being effectively removed from the crew's work area, and these caused their symptoms. Additional local measurements of pollutants are planned for the 2A.2 mission to the ISS.
Selection of space cabin atmospheres including pressure, fire and blast hazard, humidity and temperature control, etc
The selection of spacecraft and space suit atmospheres for future human space exploration missions will play an important, if not critical, role in the ultimate safety, productivity, and cost of such missions. Internal atmosphere pressure and composition (particularly oxygen concentration) influence many aspects of spacecraft and space suit design, operation, and technology development. Optimal atmosphere solutions must be determined by iterative process involving research, design, development, testing, and systems analysis. A necessary first step in this process is the establishment of working bounds on the atmosphere design space.
Atmospheric and Space Electricity (ASE) has been a part of the American Geophysical Union (AGU) since its initial founding and organization in 1919. John Fleming, who invented the vacuum tube, was the first Secretary of the AGU Terrestrial Magnetism and Atmospheric Electricity Section, and today has an AGU medal named after him. ASE played an important role in the post-World War II era of AGU, as a locus for scientific discussions regarding major ASE-related events, such as the Thunderstorm Project (1946–1949) and the 1969 Apollo 12 lightning incident. By the 1970s and 1980s, the ASE community was represented by the Committee on ASE (CASE) within the Atmospheric Sciences Section. CASE was able to bridge the gap between the fields of aeronomy and atmospheric science by sponsoring its own sessions and nominating AGU Fellow awardees. ASE business meetings at the AGU Fall and Spring Meetings lasted for hours, with anyone from the community presenting scientific ideas, field campaigns, and more - practically turning the business meeting into an ad hoc AGU session!
Space cabin atmospheres - space cabin aerosol sampling device, field aerosol generator, and survey of particle counter designs
The findings of the Atmospheric and Space Physics working group of the space shuttle mission planning activity are presented. The principal objectives defined by the group are: (1) to investigate the detailed mechanisms which control the near-space environment of the earth, (2) to perform plasma physics investigations not feasible in ground-based laboratories, and (3) to conduct investigations which are important in understanding planetary and cometary phenomena. The core instrumentation and laboratory configurations for conducting the investigations are defined.
Natural space and atmospheric environments pose a difficult challenge for designers of technological systems in space. The deleterious effects of environment interactions with the systems include degradation of materials, thermal changes, contamination, excitation, spacecraft glow, charging, radiation damage, and induced background interference. Design accommodations must be realistic with minimum impact on performance while maintaining a balance between cost and risk. The goal of applied research in space environments and effects is to limit environmental impacts at low cost relative to spacecraft cost and to infuse enabling and commercial off-the-shelf technologies into space programs. The need to perform applied research to understand the space environment in a practical sense and to develop methods to mitigate these environment effects is frequently underestimated by space agencies and industry. Applied science research in this area is critical because the complexity of spacecraft systems is increasing, and they are exposed simultaneously to a multitude of space environments.
A high-resolution spectroscopic technique, analogous to that used in the thermosphere to measure the vector wind fields in the upper troposphere and stratosphere, is described which uses narrow features in the spectrum of light scattered from the earth's lower atmosphere to provide Doppler information on atmospheric scattering and absorption. It is demonstrated that vector winds can be measured from a satellite throughout the lower atmosphere, using a multiple-etalon Fabry-Perot interferometer of modest aperture. It is found that molecular oxygen and water vapor absorption lines in the spectrum of sunlight scattered by the atmosphere are Doppler-shifted by the line of sight wind, so that they may be used to monitor the global wind systems in the upper troposphere and stratosphere.
Atmospheric effects on infrared multispectral sensing of sea-surface temperature from space
Selection of space cabin atmospheres - oxygen toxicity
SAVS (a Space and Atmospheric Visualization Science system) is an integrated system with user-friendly functionality that employs a 'push-button' software environment that mimics the logical scientific processes in data acquisition, reduction, analysis, and visualization. All of this is accomplished without requiring a detailed understanding of the methods, networks, and modules that link the tools and effectively execute the functions. This report describes SAVS and its components, followed by several applications based on generic research interests in interplanetary and magnetospheric physics (IMP/ISTP), active experiments in space (CRRES), and mission planning focused on the earth's thermospheric, ionospheric, and mesospheric domains (TIMED). The final chapters provide a user-oriented description of interface functionalities, hands-on operations, and customized modules, with details of the primary modules presented in the appendices. The overall intent of the report is to reflect the accomplishments of the three-year development effort and to introduce potential users to the power and utility of the integrated data acquisition, analysis, and visualization system.