Results for “Unfolding” — Page 11

NASA NTRSDate not supplied

Experimental Characterization of the Dimensional Stability of Deployable Composite Booms During Stowage

Thin-ply carbon fiber reinforced polymer materials offer the opportunity to create long thin-shell booms with high strength to weight ratios. These booms can be rolled up and stowed in small volumes to be later deployed. These features make them ideal for use in gossamer solar sails as well as other deployable space structures. It has been observed that stowing the booms in rolled-up configurations can cause time-dependent deformations. A comprehensive understanding of the detrimental effects of stowing the coiled booms is necessary to implement these structures in spaceflight missions. During stowage inside the spacecraft, the boom is subjected to a constant deformation/strain that causes it to relax over time, measurable by a decrease in stress. Using large deformation bending tests, the complete fold-stow-unfold-recover cycle of thin-laminate candidates for the rollable booms is characterized. Further bending and stowage testing is done at the boom level. The results from this test campaign will be used to evaluate the dimensional stability of deployable booms made from thin-ply composites that exhibit visco-elasto-plastic behavior and calibrate and validate numerical finite element models that include visco-elasto-plastic material models.

Experimental Characterization↗

NASA NTRS2018

Observing Fast Mesoscale Atmospheric Processes with a Geostationary Microwave Sounder

A geostationary microwave sounder, GeoSTAR, capable of providing continuous monitoring every 15 minutes of atmospheric temperature, water vapor, clouds, precipitation, and wind in the presence of clouds and precipitation, which will add tremendously to our ability to observe rapidly evolving dynamic atmospheric phenomena, such as hurricanes and severe storms, monsoonal moisture flow, and atmospheric rivers, has been developed at the Jet Propulsion Laboratory. GeoSTAR uses aperture synthesis to overcome the difficulty of attaining adequate spatial resolution from geostationary orbit. It is made possible with new technology that has now been developed and fully tested. Low-risk mission development can start as soon as funding becomes available. The sensor can be hosted on a commercial communications satellite, which could reduce the cost substantially. Plans have been developed at JPL for such a mission, called “GeoStorm”, focused on observing severe convective storms – tropical cyclones, mesoscale convective systems, and extratropical cyclones – with a goal of improving our understanding, modeling and prediction of these destructive phenomena. It can equally well be configured as an operational mission, where the goal is to collect data for immediate assimilation into regional forecast systems, provide “now-casting” as the storms unfold, and support post-disaster relief and recovery efforts. With key observables including vertical profiles of temperature, water vapor, wind and precipitation over a wide area, many focused applications are possible, particularly pertaining to aviation, transportation and marine operations, in both the civilian and defense domains.

Lambrigsten, Bjorn↗

NASA NTRS2021

The NASA/GSFC 94 GHz Airborne Solid State Cloud Radar System (CRS)

The NASA/Goddard Space Flight Center’s (GSFC’s) W-band (94 GHz) Cloud Radar System (CRS) has been comprehensively updated to modern solid-state and digital technology. This W-band (94 GHz) radar flies in nadir-pointing mode on the NASA ER-2 high-altitude aircraft, providing polarimetric reflectivity and Doppler measurements of clouds and precipitation. This paper describes the design and signal processing of the upgraded CRS. It includes details on the hardware upgrades (SSPA transmitter, antenna, and digital receiver) including a new reflect array antenna and solid-state transmitter. It also includes algorithms, including internal loop-back calibration, external calibration using a direct relationship between volume reflectivity and the range-integrated backscatter of the ocean, and a modified staggered-PRF Doppler algorithm that is highly resistant to unfolding errors. Data samples obtained by upgraded CRS through recent NASA airborne science missions are provided.

Radar↗

NASA NTRSDate not supplied

Preliminary Results from the Marshall Grazing Incidence X-ray Spectrometer (MaGIXS)

The Marshall Grazing Incidence X-ray Spectrometer (MaGIXS) is a sounding rocket mission that aims to observe the soft x-ray solar spectrum (0.6 – 2.5 nm) with both spatial and spectral resolution over a substantial field of view. This wavelength range has several high temperature and abundance diagnostics that can be used to assist in diagnosing the coronal heating mechanism. MaGIXS launched from White Sands Missile Range on July 30, 2021 and successfully observed the Sun through a 4’ x 33’ effective slot, producing ``overlappograms’’, where the spatial and spectral information are overlapped and must be unfolded. In this presentation, I will report on the MaGIXS launch and data collection and provide preliminary analysis of MaGIXS data.

Amy Winebarger↗

NASA NTRSDate not supplied

Preliminary Results from the Marshall Grazing Incidence X-ray Spectrometer (MaGIXS)

The Marshall Grazing Incidence X-ray Spectrometer (MaGIXS) is a sounding rocket mission that aims to observe the soft x-ray solar spectrum (0.6 – 2.5 nm) with both spatial and spectral resolution over a substantial field of view. This wavelength range has several high temperature and abundance diagnostics that can be used to assist in diagnosing the coronal heating mechanism. MaGIXS launched from White Sands Missile Range on July 30, 2021 and successfully observed the Sun through a 4’ x 33’ effective slot, producing ``overlappograms’’, where the spatial and spectral information are overlapped and must be unfolded. In this presentation, I will report on the MaGIXS launch and data collection and provide preliminary analysis of MaGIXS data.

Amy Winebarger↗

NASA NTRSDate not supplied

New Phase Change Materials for Active Photonics

Phase change materials or PCMs are truly remarkable compounds whose unique switchable properties have fueled an explosion of emerging applications in electronics and photonics. Nonetheless, if we discount their use in optical discs, PCMs’ immense application potential in photonics beyond data recording has only begun to unfold in the past decade. While the material requirements for optical or electronic data storage have been succinctly summarized as five key elements “writability, archival storage, erasability, readability, and cyclability” decades ago, these requirements are not universally relevant to the diverse set of photonic applications now being explored. It also comes as no surprise that existing PCMs, which have been heavily vetted for data storage, are not necessarily the optimal compositions for different use cases in optics and photonics. PCMs with their attributes custom-tailored for specific applications are therefore in demand as phase-change photonics continue to expand. Here we discuss the PCM selection and design strategies specifically for photonic applications as well as our recent work developing active integrated photonic devices and metasurface optics based on new PCMs tailored for photonics.

phase change materials↗

NASA NTRS2022

Molecular information theory meets protein folding

We propose an application of molecular information theory to analyze the folding of single domain proteins. We analyze results from various areas of protein science, such as sequence-based potentials, reduced amino acid alphabets, backbone configurational entropy, secondary structure content, residue burial layers, and mutational studies of protein stability changes. We found that the average information contained in the sequences of evolved proteins is very close to the average information needed to specify a fold ~2.2 ± 0.3 bits/(site operation). The effective alphabet size in evolved proteins equals the effective number of conformations of a residue in the compact unfolded state at around 5. We calculated an energy-to-information conversion efficiency upon folding of around 50%, lower than the theoretical limit of 70%, but much higher than human built macroscopic machines. We propose a simple mapping between molecular information theory and energy landscape theory and explore the connections between sequence evolution, configurational entropy and the energetics of protein folding.

Ignacio E. Sánchez↗

NASA NTRS2023

Artemis I Is the First NASA Mission to Use Wi-Fi® in Lunar Orbit

During the countdown procedure for the Artemis I launch, the flight control team at NASA’s Johnson Space Center in Houston activated a set of cameras looking back at the vehicle from the wing-tips of the solar arrays. Throughout the flight, the team used photos from these cameras to survey and assess the condition of the vehicle, monitor for micrometeorite damage, and maintain situational awareness. The ground control team was even able to watch live video as the solar array wings unfolded. The cameras continued to store imagery to internal memory as well as send photos over Wi-Fi® even as the vehicle lost communication with Earth as it flew behind the moon. Artemis I is the first NASA mission to use WiFi in lunar orbit.

Wi-Fi↗

NASA NTRS2021

Lila: Optimal Dispatching in Probabilistic Temporal Networks using Monte Carlo Tree Search

Executing a Probabilistic Simple Temporal Network (PSTN) amounts at scheduling, i.e. \textit{dispatch}, a set of events under time uncertainty. This constitutes a NP-hard online optimization problem. The right execution time must be dynamically assigned to each event of the PSTN such that the temporal constraints are met, whereas activity durations are progressively observed as the execution unfolds. We propose a dispatching algorithm based on Monte Carlo Tree Search, called Lila, with the following characteristics: (i) it is an anytime algorithm, both offline and online, proven asymptotically optimal; (ii) it returns the current probability of success, either before or at any moment during operations; (iii) it handles any possible continuous or discrete, even non-parametric, probability distributions, as well as inter-dependencies between random variables, exogenous and endogenous uncertainty; and (iv) can be easily extended to handle probabilistic external events, PSTNs with resources, PSTNs with cutoff times and precondition chains, etc. Lila is universal in the sense that it can handle any dispatching protocol, simply by specifying it to the algorithm. It has the unlimited flexibility offered by the simulation paradigm, whilst it asymptotically converges to optimal decisions and/or robustness approximations.

Chien, Steve A.↗

NASA NTRSDate not supplied

The Third Flight of the Marshall Grazing Incidence X-Ray Spectrometer (MaGIXS-3)

The Marshall Grazing Incidence X-ray Spectrometer (MaGIXS) is the first X-ray slitless imaging spectrograph sounding rocket instrument designed to observe spectrally dispersed soft X-ray images of the solar corona over a wide field-of-view. During the first flight of MaGIXS (MaGIXS-1), occurred on 30 July 2021, several emission lines from coronal structures including X-ray bright points were observed. Further, MaGIXS-1 analysis also demonstrated the successful inversion of overlappograms using robust unfolding algorithms. Given the demonstrated success of MaGIXS-1, the second flight of the instrument with a simplified optical design, MaGIXS-2, is scheduled for 2024 to observe high temperature diagnostic emission lines. Results from MaGIXS-1 discovered dominant missing emission lines near 15A, arising from relatively cool plasma that peaks around 2 MK. This wavelength region hosts several closely spaced satellite lines of Fe XVII, Fe XVI and Fe XV ions, which are expected to be enhanced at lower temperatures and are currently unmodeled in the CHIANTI atomic database. This wavelength region offers one of the most unique diagnostics to measure electron temperature, as well as signatures of equilibrium state of the plasma in active regions, which has not been studied so far. The goal of MaGIXS-3 mission is the to determine coronal heating parameters, such as the spatial and temporal properties of coronal heating events, by measuring discriminating observations, such as electron temperature, effective temperature, density, abundance, and departures from thermal equilibrium of the plasma, by observing the Sun in the SXR wavelength range. To meet this goal, the MaGIXS instrument will be upgraded with a new X-ray telescope mirror that will provide higher spatial and spectral resolution and throughput, allowing for spectral lines to be observed at the relevant spatial and temporal scales. In addition, MaGIXS-3 will also carry The Resolving Inversion Context X-ray Spectrometer (TRICXS), a high dispersion Bragg crystal spectrometer to spectrally resolve the lines near 14.9 to 15.9A, critical to unlock the full diagnostic potential of this wavelength range. Here we will present the preliminary concept design of MaGIXS-3 and discuss the potential observations.

X-ray Imaging↗

NASA NTRSDate not supplied

Functional Task Tests in Partial Gravity During Parabolic Flight

BACKGROUND Understanding how critical mission tasks are performed in partial gravity such as on the moon or Mars is necessary to define effective and comprehensive countermeasure strategies for preserving crew performance during exploration missions. We studied the performance of tasks such as standing, walking, and jumping during the partial gravity phases of parabolic flight. We hypothesized that the acute effects of partial gravity on vestibular, proprioceptive, and sensorimotor functions would negatively impact performance. METHODS Twelve subjects were tested over three flights of 30 parabolas each, including 10 parabolas at 0.25g, 10 parabolas at 0.5g, and 10 parabolas at 0.75g. Subjects also performed tests in 1g between parabolas. During the sit-to-stand with obstacle walk task, subjects rose from a seated position and walked as quickly as possible straight ahead towards a cone (4 m distance), walked around the cone making a 180° left turn, returned, and sat in the chair. On the way to and from the cone, subjects stepped over a 30 cm high obstacle. For the recovery from fall task, subjects lay prone for the pull-up phase and initial 10 sec of the parabola. Then they were asked to rise as quickly as possible and maintain a quiet stance for 10 sec. The tandem rail balance task involved standing with both feet on a 4.5 cm wide rail. The time ended when subjects either stepped off the rail or grabbed on to support straps. The jump down task started with the subjects standing on a 30 cm high platform, then the subjects were instructed to step off the platform, land with both feet simultaneously, and settle in a quiet stance. The cone of stability task involved subjects leaning about the ankles as far as they could in the anterior, posterior, and lateral directions without unfolding their arms or taking a step. The center of pressure distance between endpoints was calculated. Data were collected using inertial measurement units (Opal V2, APDM, Portland, OR) worn on the head and trunk, heart rate monitors (RS800CX, Polar, Kempele, Finland), and a force plate (Bertec, Columbus, OH). RESULTS Gravity level had a significant effect on performance, with the greatest changes from 1g tending to be at the 0.25g level (Table 1). Lower gravity levels were associated with increased times to complete the sit-to-stand obstacle walk task and the recovery from fall task, decreased change in heart rate during the recovery from fall task, decreased rail balance times, and increased cone of stability distance in the anterior-posterior direction. Table 1. Functional task performance at different gravity levels during parabolic flight. Measure0.25g0.5g0.75g1gp-valueSit-to-stand with obstacle walk time (sec)9.8 ±1.4*7.2 ±0.76.9 ±0.8*7.4 ±0.9<0.001Recovery from fall time to settle (sec)5.3 ± 0.9*4.6 ± 0.84.2 ± 0.64.3 ± 0.70.002Recovery from fall change in heart rate (bpm)6.0 ± 7.3*11.2 ± 6.5*14.9 ± 4.915.9 ± 6.5<0.001Rail balance with eyes open time (sec)2.7 ±0.8*4.8 ±2.16.6 ±4.78.4 ±6.70.031Rail balance with eyes closed time (sec)1.6 ±0.4*2.1 ±0.42.4 ±0.62.6 ±0.8<0.001Jump down time to settle (sec)2.1 ± 0.41.9 ± 0.42.0 ± 0.31.8 ± 0.30.328Cone of stability –anterior-posterior (cm)20.8 ±2.7*18.8 ±2.218.6 ±1.717.9 ±2.00.039Cone of stability –lateral (cm)26.8 ±6.624.4 ±2.123.0 ±2.123.8 ±2.30.215p-value: one-way repeated measures analysis of variance; *Significant pairwise difference from 1g (p<0.05). DISCUSSION These data suggest that there is a dose-response relationship between gravity level and functional task performance. The largest changes in performance were expected at the lowest gravity level (0.25g) because subjects would no longer be able to use the gravitational reference for the perception of upright. Understanding the extent of performance deficits informs the risks and design of countermeasures for exploration spaceflight missions. ACKNOWLEDGEMENT This work is supported by NASA’s Human Research Program Human Health Countermeasures Element.

T R Macaulay↗

NASA NTRS2024

Expanding Impact with the James Webb Space Telescope: Combining Art, Science, and Technology for Public Outreach

This archived content may contain outdated information or references that may not reflect current policy or programs. NASA’s James Webb Space Telescope revealed its first images on July 12, 2022 and has been used for groundbreaking science since. Scientific exploration transcends international borders, making a mission like Webb feasible with collaborators including the European Space Agency (ESA), and Canadian Space Agency (CSA). Communication about NASA’s discoveries about the universe, so essential for involving the public, likewise needs to be inclusive to all. Art is a tool for cutting across the boundaries of language, culture, and ability, and serves as a bridge between the technical and non-technical communities. Art makes the beauty and nuance of science and engineering accessible in ways that may not be readily perceived to those outside of those communities of practice. Equitable and inclusive outreach endeavors are challenging to implement while considering language translations, culture context, sensory methods, and technology capabilities. Formats including “Unfolding the Universe'' virtual reality platform has allowed for a wider audience to interact with the Webb images including sounds, visual aids, and talks by the scientists and engineers who worked on Webb. This VR platform has been expanded to highlight the ESA contributors to the mission and will be showcased internationally. The Webb first images were also translated into sounds as a method of inclusion for anyone with sight disabilities. We will explore some successful outreach methods and suggestions for inclusivity in future.

Outreach↗

NASA NTRSDate not supplied

Study of Coronal Heating in Solar Active Regions Using Wide-Field Imaging Spectroscopy: Hinode EIS Slot Observations

Understanding the frequency of heating events that keep the coronal plasma at several million Kelvin above the photospheric temperature of~ 6000K, is one of the most important problems in solar astrophysics. Spectroscopic observations of the Sun in the extreme ultraviolet (EUV) indicate that the coronal plasma reaches temperatures from 1 to 5 MK in active regions. It is also established that temperature in active regions can vary strongly with time and, moreover, contain sub-regions that evolve and develop separately. Tracking the spatio-temporal evolution of temperature requires continuous observation of the entire active region via imaging and spectroscopy. Traditional slit imaging spectroscopy probes plasma heating in solar active regions through observations of diagnostic emission lines and the resulting data are spectrally pure. Here, imaging is performed through rastering process, which severely limits co-temporal observations and often can be slow to miss events that evolve at other portions of the active region. In contrast, wide-field imaging spectroscopy offer simultaneous coverage of a large field of view as well as obtain spectral information in the same direction. This data suffers from spatial-spectral confusion, and are called spectroheliograms. Using the state-of-the-art inversion techniques that are developed recently, now spectroheliogram data can be unfolded to yield spectrally pure maps of large fields over long duration of observations. We use wide slit data, usually referred as ‘slot’, from the EUV Imaging Spectrometer (EIS) onboard Hinode satellite, focusing on active region observations. Here, we present our study of coronal heating in an active region using a long duration Hinode EIS slot observation.

Active region heating↗

NASA NTRSDate not supplied

Equitable and Inclusive Public Outreach with the James Webb Space Telescope: Combining Art, Science, and Technology

This archived content may contain outdated information or references that may not reflect current policy or programs. NASA’s James Webb Space Telescope revealed its first images on July 12, 2022 and has been used for groundbreaking science since. Scientific exploration transcends international borders, making a mission like Webb feasible with collaborators including the European Space Agency (ESA), and Canadian Space Agency (CSA). Communication about NASA’s discoveries about the universe, so essential for involving the public, likewise needs to be inclusive to all. Art is a tool for cutting across the boundaries of language, culture, and ability, and serves as a bridge between the technical and non-technical communities. Art makes the beauty and nuance of science and engineering accessible in ways that may not be readily perceived to those outside of those communities of practice. Equitable and inclusive outreach endeavors are challenging to implement while considering language translations, culture context, sensory methods, and technology capabilities. Formats including “Unfolding the Universe'' virtual reality platform has allowed for a wider audience to interact with the Webb images including sounds, visual aids, and talks by the scientists and engineers who worked on Webb. This VR platform has been expanded to highlight the ESA contributors to the mission and will be showcased internationally. The Webb first images were also translated into sounds as a method of inclusion for anyone with sight disabilities. We will explore some successful outreach methods and suggestions for inclusivity in future.

Outreach↗

NASA NTRSDate not supplied

Equitable and Inclusive Public Outreach with the James Webb Space Telescope: Combining Art, Science, and Technology

This archived content may contain outdated information or references that may not reflect current policy or programs. NASA’s James Webb Space Telescope revealed its first images on July 12, 2022 and has been used for groundbreaking science since. Scientific exploration transcends international borders, making a mission like Webb feasible with collaborators including the European Space Agency (ESA), and Canadian Space Agency (CSA). Communication about NASA’s discoveries about the universe, so essential for involving the public, likewise needs to be inclusive to all. Art is a tool for cutting across the boundaries of language, culture, and ability, and serves as a bridge between the technical and non-technical communities. Art makes the beauty and nuance of science and engineering accessible in ways that may not be readily perceived to those outside of those communities of practice. Equitable and inclusive outreach endeavors are challenging to implement while considering language translations, culture context, sensory methods, and technology capabilities. Formats including “Unfolding the Universe'' virtual reality platform has allowed for a wider audience to interact with the Webb images including sounds, visual aids, and talks by the scientists and engineers who worked on Webb. This VR platform has been expanded to highlight the ESA contributors to the mission and will be showcased internationally. The Webb first images were also translated into sounds as a method of inclusion for anyone with sight disabilities. We will explore some successful outreach methods and suggestions for inclusivity in future.

Outreach↗

NASA NTRS2024

Biofabrication in Space - A Perspective

Human exploration of Mars is one of the primary goals of NASA. A three-year human exploration mission to Mars is a viable design reference mission (Design Reference Mission). If we are sending a four member crew, comprehensive understanding of the health conditions of the crew is important. Based on the biomedical results of long-duration crew members at ISS, and during gravitational transitions, a few maladaptation have been observed. Discovering the root-cause of these aberrations and finding suitable mitigations at the molecular and cellular levels are of importance for a successful mission. Developing and executing the technologies to carry out tissue generation in space as well as the development of an analog hardware for tissue generation under terrestrial conditions will be discussed. These tissues were typically used to develop disease models and drug toxicology studies for several weeks and many other applications. The significant progress made during the last two decades have unfolded developments in organ generation, stem cell generation in space. When you remove the gravitational force during these cellular building processes while in space, other forces like surface tension, intermolecular forces, Coriolis force, loss of convection, reduced shear force, dominate the environment leading to behavior that we may not observe under terrestrial conditions. Based on these discoveries, the fundamental mechanisms could be better understood and new insights into bioprocesses could be developed for an exciting future.

Antony Jeevarajan↗

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↗

NASA NTRSDate not supplied

Generalized Augmented-State Covariance Analysis for Spaceflight

The use of linear covariance analysis techniques, also known as LinCov, has been used extensively for more than a half century for spaceflight applications. Originally, its primary purpose was to facilitate navigation analysis. For many past and current applications, the specific implementations only support navigation studies still. When the concept of an augmented-state linear covariance analysis approach was initially introduced that allowed for both navigation and trajectory dispersion analysis, the enhancement was motivated and primarily utilized to support navigation filter tuning and error budget analysis. Relatively few utilize this alternate augmented-state formulation of LinCov due to its additional complexity. The untapped potential of the augmented-state linear covariance analysis technique slowly unfolded in the past two-decades as its capability to rapidly and reliably capture the integrated closed-loop guidance, navigation, and control (GN&C) system performance became more apparent. Even with this dual purpose of generating insights to both navigation errors along with trajectory and delta-v dispersions, the core theoretical development had a heavy emphasis on the impacts of the navigation system and largely neglected the details of the actual guidance, targeting, and control systems. This paper extends the navigation-centric theoretical development by formulating a generalized augmented-state covariance analysis (GAUSCOV) technique that allows for the intricacies of a variety of targeting and control strategies along with ground planning and mission operations to be more formally included in assessing the impacts to spaceflight GN&C system performance.

Linear Covariance Analysis↗