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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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At least 469 records · Page 26
All sourcesNASA NTRSDOE OSTI
NASA NTRSDate not supplied

Momentum Management Strategies for Solar Cruiser and Beyond (ISSS 2023)

Solar Cruiser is a small (ESPA-class) satellite Technology Demonstration Mission (TDM) to mature solar sail propulsion technology using a solar sail larger than 1600 square meters, demonstrating performance both as a propulsion system and a stable pointing platform for science observations in an artificial halo orbit sunward of the Sun-Earth Lagrange Point 1 (sub-L1). To ensure attitude control throughout the mission, momentum accumulated on the reaction wheels (RWs) used for attitude control must be managed such that the sailcraft does not lose control due to RW momentum saturation. Momentum builds up on the wheels from environmental disturbance torques caused by solar radiation pressure combined with a center of mass (CM)/center of pressure (CP) offset, deformed sail shape, and an off-sun pointing angle, plus other factors. Solar Cruiser mitigates this momentum build up by utilizing an Active Mass Translator (AMT) that maintains pitch and yaw momentum by trimming the CM/CP offsets, and thrusters to maintain roll momentum. A survey was conducted by the Solar Cruiser team to assess the feasibility and tradeoffs of novel momentum management concepts such as Reflectivity Control Devices (RCD’s), different thruster configurations, and control vanes and other articulated control surfaces. In addition, techniques to reduce disturbance torque buildup, such as reducing boom tip deflections and clock angle control, were assessed. Similar sailcraft momentum management strategies can be used for future missions such as space weather monitoring and Earth magnetotail science missions

Solar Sail↗
NASA NTRS2023

Space Weather Investigation Frontier (SWIFT)

The Space Weather Investigation Frontier (SWIFT) mission will aim at making major discoveries on the three-dimensional structure and dynamics of heliospheric structures that drive space weather. The focus will be on Interplanetary Coronal Mass Ejections (ICMEs) that originate from massive expulsions of plasma and magnetic flux from the solar corona. They cause the largest geomagnetic storms and solar energetic particle events, threatening to endanger life and disrupt technology on Earth and in space. A big current problem, both regarding fundamental solar-terrestrial physics and space weather, is that we do not yet understand spatial characteristics and temporal evolution of ICMEs and that the existing remote-sensing and in-situ observatories are not suited for resolving multi-layered and evolutionary structures in these massive storm drivers. Here, we propose a groundbreaking mission concept study using solar sail technology that, for the first time, will make continuous, in-situ multi-point observations along the Sun-Earth line beyond the Lagrange point L1 (sub-L1). This unique position, in combination with L1 assets, will allow distinguishing between local and global processes, spatial characteristics, temporal evolution, and particle energization mechanisms related to ICMEs. In addition, measurements of the magnetic field in earthbound ICMEs and their sub-structures from the SWIFT location will double the current forecasting lead-times from L1. This concept also paves the way for missions with increasingly longer forecasting lead-times, addressing NASA and NOAA’s space weather goals, as set forth by the Decadal Survey. The objective of this communication is to inform the community of the ongoing effort, including plans to further develop the mission concept, supported by the Heliophysics Flight Opportunities Studies (HFOS) program under NASA’s Research Opportunities in Space and Earth Sciences (ROSES).

M. Akhavan-Tafti↗
NASA NTRSDate not supplied

Evolution of Astrodynamics for Multibody Environments, Numerical Precision and Dynamical Understanding

The innovative nature of dynamical systems theory and its applications in trajectory design enabled many recent missions by opening up new transfer and capture opportunities to meet mission requirements, reduce fuel costs, and address various launch constraints and contingencies. With a combination of proven numerical methods and an advanced understanding of the dynamics, an ‘experienced’ user can rapidly design multibody and cislunar missions such as Lunar IceCube and Artemis/Themis and relatively quickly conceive trajectory concepts for Sun-Earth mission orbits, such as the Space Weather Follow On-L1 Lissajous orbit—one that can be achieved and maintained.

David C Folta↗
NASA NTRSDate not supplied

The Miniaturized Electron Proton Telescope, MERiT onboard Lunar Gateway

The Lunar Gateway or the Gateway, part of NASA’s Artemis program, is a space station orbiting around the moon The cis-lunar Gateway platform provides the opportunity for Heliophysics investigations to advance our knowledge of the coupled Sun-Earth system and the opportunity better understand the radiation environment in order to support and improve crew safety and operations at the Moon and beyond. The Heliophysics Environmental and Radiation Measurement Experiment Suite (HERMES) is a suite of instruments place on the outside of the Habitation and Logistics Outpost ( HALO) monitor the Sun’s radiation environment and space weather. HERMES, led byNASA’s Goddard Space Flight Center, will monitor lower energy solar particles critical to scientific investigations of the Sun including the solar winds. Additional suite of instruments provided by ESA, the European Radiation Sensors Array (ERSA) will complement space weather studies. We report here on the energetic particle instrument, the Minaturized Electron Proton Telescope (MERiT) on board HERMES designed to measure electrons and protons in the energy range ~0.3-9. MeV and ~1-190 MeV in 11 and 20 differential energy channels respectively. MERiT is a solid state detector telescope with the two sensor heads:one looking sunward and the other anti-sunward. MERiT will help advance our understanding of solar energetic particles, low energy cosmic rays and energetic electrons in the magnetospheric tail. We will describe the instrument in details and the science topics it is expected to address. Lunar Gateway is currently expected to launch in 2024

Shri Kanekal↗
NASA NTRS2023

An Updated Geomagnetic Index-Based Model for Determining the Latitudinal Extent of Energetic Electron Precipitation

Energetic Electron Precipitation (EEP) from the Earth's plasma sheet and the radiation belts is an important feature of atmospheric dynamics through their destruction of ozone in the lower thermosphere and mesosphere. Therefore, understanding the magnitude of the atmospheric impact of the Sun-Earth interaction requires a comprehensive understanding of the intensity and location of EEP. This study improves the accuracy of a previous pressure-corrected Dst model that predicts the equatorward extent of >43, >114, and >292 keV EEP using the measurements from the Medium Energy Proton Electron Detector detector of six National Oceanic and Atmospheric Administration/Polar Orbiting Environmental Satellites and EUMETSAT/METOP satellites. The improvement is achieved through multiple linear regression of pressure-corrected Dst and pressure-corrected Ring Current (RC) indices. The RC index mitigates the baseline variation of the Dst index that created an inherent solar cycle bias in the previous model. The new model is then extended to the Southern Hemisphere (SH) after removing the South Atlantic Anomaly longitudes from the data. More than 80% of the residuals lie within ±1.8° Corrected Geomagnetic Latitude (CGMLat) in the Northern Hemisphere and within ±1.98° CGMLat in the SH.

E. M. Babu↗
NASA NTRS2023

Geoeffectiveness of Interplanetary Shocks Controlled By Impact Angles: Past Research, Recent Advancements, and Future Work

Interplanetary shocks are disturbances commonly observed in the solar wind. IP shock impacts can cause a myriad of space weather effects in the Earth’s magnetopause, inner magnetosphere, ionosphere, thermosphere, and ground magnetic field. The shock impact angle, measured as the angle the shock normal vector performs with the Sun-Earth line, has been shown to be a very important parameter that controls shock geoeffectivess. An extensive review provided by Oliveira and Samsonov (2018) summarized all the work known at the time with respect to shock impact angles and geomagnetic activity; however, this topic has had some progress since Oliveira and Samsonov (2018) and the main goal of this mini review is to summarize all achievements to date in the topic to the knowledge of the author. Finally, this mini review also brings a few suggestions and ideas for future research in the area of IP shock impact angle geoeffectiveness.

interplanetary shocks↗
NASA NTRSDate not supplied

The Coronal Microscale Observatory

It has been a longstanding challenge to identify the mechanisms responsible for heating the solar corona, in part because heating, whether by waves or magnetic reconnection, is thought to be concentrated in thus far unresolved volumes with characteristic scales ≲100 km. The Coronal Microscale Observatory (CMO) is a mission concept designed to image these microscale heating events, identify the dominant physical mechanisms that control their initiation and evolution, and understand their effects on the formation of the solar wind. CMO positions three spacecraft and three instruments near the Sun-Earth L1 Lagrange point. One instrument is a cluster of 6 coaligned extreme ultraviolet (EUV) telescopes that image a common field of view with ultrahigh angular resolution (0.02−0.07 arcsec) in narrow wavelength bands, each sensitive to emission from plasma in a limited temperature range. The second instrument is a multi-band, full-disk, externally occulted coronagraph. Finally, a two-band fine scale EUV imager (resolution 0.3 arcsec) provides a larger field of view for context and additional science. The three CMO craft fly in precise formation to ensure that the EUV imagers point to a desired target on the Sun and the external occulter accurately blocks the solar disk. The novel mission architecture arises from the intrinsically long EUV focal length (≳100 m) of diffractive optics known as photon sieves, which achieve nearly diffraction-limited EUV imaging but require a distributed telescope, in which the optics and- the image sensors are on separate spacecraft. Two spacecraft are also needed to position an external occulter 200 m in front of the coronagraph, which enables visible-light imaging of the corona very close to the solar limb with undiminished angular resolution. Recent advances in fabricating ultraprecise and smooth reflective optics suggest that a conventional (single spacecraft)EUV “microscope” may now be feasible in an Explorer-class mission that could achieve a subset of the scientific objectives of CMO.

Douglas Rabin↗
NASA NTRSDate not supplied

The Impact of Impulsive Vs Finite Maneuver Modeling on Launch Transfer Trajectories for The Roman Space Telescope

The Nancy Grace Roman Space Telescope (RST) is a flagship astrophysics observatory developed by the NASA Goddard Space Flight Center for launch in the mid-2020’s. The nominal mission orbit for RST is a Sun-Earth L2 quasi-halo orbit subject to stringent geometric and dynamical constraints necessary for achieving mission science objectives. After award of the launch vehicle contract to SpaceX, comparing the launch solutions produced by the RST Flight Dynamics team and the SpaceX team revealed that despite targeting the same interface states, modeling the second-stage insertion burn with an impulsive delta-V vs. a higher fidelity finite burn model can result in substantial differences in achieved libration point orbit properties. In this paper, these differences are explored and leveraged to update the models and targeting strategies used by the RST Flight Dynamics tools. These updates allow the mission to achieve more flight-like ascent and insertion dynamics for the libration point transfer, as well as reveal interesting relationships between the dynamics of impulsive models and finite burn models for libration point transfer trajectories in general.

Lauren Schlenker↗
NASA NTRS2024

Azimuthal Size Scales of Solar Wind Periodic Density Structures

Periodic Density Structures (PDSs) are quasi-periodic variations of solar wind density ranging from a few minutes to a few hours. PDSs advect with the solar wind and have radial length scales (Lx) of tens to several thousand Mm, thus belonging to the class of “mesoscale structures”. Current interplanetary multi-spacecraft observations are not at spatial separations capable of directly measuring the 3D size scale of PDSs or other mesoscale structures. Instead, previous investigations estimated characteristic spatial scales in solar wind parameters using cross-correlation and/or coherence analysis applied to multi-spacecraft observations. For solar wind density and interplanetary magnetic field (IMF) intensity, the reported size scales perpendicular to the Sun-Earth line (Ly) ranged between ≈30 and ≈200 Earth Radii (RE). Here, we implemented a similar approach on the same parameters but focused on high density slow solar wind intervals with PDSs observed by the Wind and ARTEMIS-P1 spacecraft. Additionally, this is the first statistical study of the IMF intensity periodicities in relation to PDSs. We identified intervals in which the two spacecraft observed the same periodicity obtaining two PDS groups based on their radial length scale: Lx1 ≈86RE and Lx2 ≈35RE. Then, we classified the events based on the periodic variations’ coherence level. Reproducing the results with simulations of the PDSs’ transit, we inferred the Ly order of magnitudes for the two PDS groups: Ly1 ≈340RE and Ly2 ≈187RE. Knowing the PDSs’ size scales is fundamental to constrain models aimed at reproducing these structures and is critical to better understand the PDS-magnetosphere coupling.

Interplanetary physics↗
NASA NTRSDate not supplied

The Webb Space Telescope - An Engineering Marvel Story

This presentation will provide an overview of the James Webb Space Telescope (JWST) and its engineering development process. JWST has succeeded the Hubble Space Telescope in our quest for the first galaxies formed out of the darkness of the early universe. Since its launch in December 2021, JWST has helped us understand how these galaxies evolved over billions of years, how stars and planetary systems form, what exoplanets look like and if they can harbor life. JWST uses a ~6.5-m-diameter primary mirror to collect infrared light, which is sent to four scientific instruments. It operates at the second Sun-Earth Lagrange point and has a five-layer sunshield to be able to operate at cryogenic temperatures. JWST is an international effort of NASA and the European and Canadian Space Agencies.

James Webb Space Telescope↗
NASA NTRSDate not supplied

Open-Source Data Engineering at NASA: CCMC's Approach to Managing Petabyte-Scale Heliophysics Data

The Community Coordinated Modeling Center (CCMC) at NASA Goddard Space Flight Center (GSFC) leads heliophysics research by providing open access to numerous models and their outputs. Our resources are available on-demand and continuously updated with real-time data, covering sun-earth interactions across multiple domains. These domains include coronal, heliosphere, inner and global magnetosphere, ionosphere, thermosphere, and lower atmosphere interactions. Operating in a hybrid environment, CCMC utilizes both self-owned hardware and Amazon Web Services (AWS) cloud infrastructure. Managing petabytes of data across multiple locations necessitates robust data engineering solutions. To address this challenge, CCMC has adopted industry-standard and open-source tools. We use Apache Airflow as our primary data engineering platform, Python for scripting and data processing, and GitLab for version control and CI/CD. Additionally, we employ Kubernetes for containerized services, Grafana and Prometheus for metrics and monitoring, and Terraform and Puppet for reproducible infrastructure as code. This presentation will discuss lessons learned from our data engineering experiences, platforms evaluated but found unsuitable for our scientific data requirements, and specific techniques developed to enhance data transfer speed and reliability. By using these technologies effectively, CCMC continues to advance heliophysics research through efficient data management and open-access modeling.

space weather↗
NASA NTRSDate not supplied

The Return of the ICPS: A Statistical Perspective on Artemis Upper Stage Disposal

Prior to the launch of Artemis I, it was discovered that the Interim Cryogenic Propulsion Stage (ICPS) of the Space Launch System may not dispose heliocentrically as intended. This paper summarizes the results of an investigation which looked into why the ICPS may return in less than a year for certain Launch Days. Evidence is presented showing the ICPS mimics the behavior of known Three-Body Periodic Orbits for certain Sun-Earth geometries. This paper discusses the primary mechanisms causing ICPS to return, describes the statistics of these returns, and also discusses interactions between Artemis I mission design and the lunar month.

W B Stein↗
NASA NTRSDate not supplied

The Return of the ICPS: A Statistical Perspective on Artemis Upper Stage Disposal

Prior to the launch of Artemis I, it was discovered that the Interim Cryogenic Propulsion Stage (ICPS) of the Space Launch System may not dispose heliocentrically as intended. This paper summarizes the results of an investigation which looked into why the ICPS may return in less than a year for certain Launch Days. Evidence is presented showing the ICPS mimics the behavior of known Three-Body Periodic Orbits for certain Sun-Earth geometries. This paper discusses the primary mechanisms causing ICPS to return, describes the statistics of these returns, and also discusses interactions between Artemis I mission design and the lunar month.

W. B. Stein↗
DOE OSTI2024

Effects of Proton Irradiation on the Performance of Skipper CCDs

Skipper CCDs are a mature detector technology that has been suggested for future space telescope instruments requiring sub-electron readout noise in the near-ultraviolet to the near-infrared. While modern skipper CCDs inherit from the radiation-tolerant p-channel detectors developed by LBNL, the effects of high doses of ionizing radiation on skipper CCDs (such as those expected in space) remains largely unmeasured. We report preliminary results on the performance of p-channel skipper CCDs following irradiation with 217-MeV protons at the Northwestern Medicine Proton Center. The total nonionizing energy loss (NIEL) experienced by the detectors exceeds 6 years at the Sun-Earth Lagrange Point 2 (L2). We demonstrate that the skipper amplifier continues to function as expected following this irradiation. Owing to the low readout noise of these detectors, controlled irradiation tests can be used to sensitively characterize the charge transfer inefficiency, dark current, and the density and time constants of charge traps as a function of proton fluence. We conclude with a brief outlook toward future tests of these detectors at other proton and gamma-ray facilities.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
NASA NTRS2000

Multimission Space and Solar Physics Microspacecraft

The solar fields and particles environment and its interaction with planetary magnetospheres are not only of considerable scientific interest, they can impact human endeavors as well.

microspacecraft space weather space physics solar ↗
NASA NTRS2006

Near Sun Free-Space Optical Communications from Space

Free-space optical communications offers expanded data return capacity, from probes distributed throughout the solar system and beyond. Space-borne and Earth-based optical transceivers used for communicating optically, will periodically encounter near Sun pointing. This will result in an increase in the scattered background light flux, often contributing to degraded link performance. The varying duration of near Sun pointing link operations relative to the location of space-probes, is discussed in this paper. The impact of near Sun pointing on link performance for a direct detection photon-counting communications system is analyzed for both ground- and space-based Earth receivers. Finally, impact of near Sun pointing on spaceborne optical transceivers is discussed.

free-space↗
NASA NTRS2014

How the Sun Knocks Out My Cell Phone from 150 Million Kilometers Away

Large solar particle events (SPE) threaten many elements of critical infrastructure. A 2013 study by Lloyds of London and Atmospheric and Environmental Research recently found that if a worst-case solar event like the 1859 Carrington Event struck our planet now, it could result on $0.6-$2.36 trillion in damages to the economy. In March 2014, researchers Y. D. Liu et al. revealed that just such an event had narrowly missed Earth in July 2012. The event was observed by the STEREO A spacecraft. In this presentation, we examine how the sun can pack such a punch from 150 million km away, the threats such solar particle events pose, their mechanisms and the efforts NASA and other space agencies are carrying out to understand and mitigate such risks.

geomagnetic storms↗