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To answer NASA's call for a sensitive X-ray observatory in the 2030s, we present the High Energy X-ray Probe (HEX-P) mission concept. HEX-P is designed to provide the required capabilities to explore current scientific questions and make new discoveries with a broadband X-ray observatory that simultaneously measures sources from 0.2 to 80 keV. HEX-P's main scientific goals include: 1) understand the growth of supermassive black holes and how they drive galaxy evolution; 2) explore the lower mass populations of white dwarfs, neutron stars, and stellar-mass black holes in the nearby universe; 3) explain the physics of the mysterious corona, the luminous plasma close to the central engine of accreting compact objects that dominates cosmic X-ray emission; and 4) find the sources of the highest energy particles in the Galaxy. These goals motivate a sensitive, broadband X-ray observatory with imaging, spectroscopic, and timing capabilities, ensuring a versatile platform to serve a broad General Observer (GO) and Guest Investigator (GI) community. In this paper, we present an overview of these mission goals, which have been extensively discussed in a collection of more than a dozen papers that are part of this Research Topic volume. The proposed investigations will address key questions in all three science themes highlighted by Astro2020, including their associated priority areas. HEX-P will extend the capabilities of the most sensitive low- and high-energy X-ray satellites currently in orbit and will complement existing and planned high-energy, time-domain, and multi-messenger facilities in the next decade. [ABSTRACT FROM AUTHOR]

The article "Books in Space!" from Science Scope discusses the NASA mission CINDI (Ion-Neutral Dynamics Investigation) and its study of Earth's ionosphere. Two middle school students, Jake and Lily, engage in a discussion about the mission's impact on Earth's atmosphere and technology. The article emphasizes the importance of reading in science education to foster curiosity, critical thinking, and scientific literacy among students. It encourages students to explore space-based missions and planetary movements to enhance their understanding of the universe. [Extracted from the article]

The Artemis program and lunar gateway present an opportunity to advance NASA’s presence away from Earth’s orbit and back to the Moon. Astronauts will be faced with many dermatological challenges unique to the lunar environment, such as the surface material on the Moon. We used PubMed and Google Scholar to perform a literature review with articles related to the effects of lunar dust on skin collated and analyzed to assess the dermatological implications of these missions. The effects of lunar dust on wound generation and healing were reviewed, while also analyzing passive and active measures used to minimize astronaut exposure to lunar dust. A myriad of methods involving advances in medicine and engineering (e.g. bioinspired texturing of materials, staged decontamination, emollients) will need to be employed to best protect astronauts from the effects of lunar surface materials and other insults to best protect the Artemis astronauts. These advances will help with future NASA missions to Mars and beyond as other terrestrial space bodies will likely present astronauts with similar dermatological insults from surface materials and regolith. Dermatologists can serve a role in helping researchers develop techniques to protect skin health and understand the pathophysiology involved with lunar dust exposure. [ABSTRACT FROM AUTHOR]

NASA conducted a launch vehicle ground-wind-loads investigation at the NASA Langley Transonic Dynamics Tunnel to investigate wind-induced oscillations (WIOs) of a launch vehicle when exposed to ground winds before launch. Previous publications from this effort have documented the effects of an atmospheric-boundary-layer profile on WIO response and the correlation process between model-scale and full-scale wind characteristics and resulting structural loads. This paper will focus on the importance of aeroelastic scaling and the impact of Reynolds number on WIO response. As described in the literature and confirmed in the present investigation, aeroelastic effects can significantly increase the magnitude of measured loads. Additionally, vortex shedding is sensitive to nuances of the flow in the shear layer, which is governed by Reynolds number. Many wind-tunnel facilities are not capable of producing flight Reynolds numbers for the ground-wind-loads problem. At very low Reynolds numbers, laminar shear layers exhibit different behavior, resulting in different vortex frequencies, oscillating lift magnitudes, and motion sensitivities. This investigation demonstrated that low Reynolds number testing can yield substantially lower dynamic loads with less aeroelastic coupling than those acquired at flight-representative Reynolds numbers for a resonant WIO event. Additionally, a resonant response phenomenon present at flight Reynolds number was absent at low Reynolds number. Conversely, for nonresonant WIO response conditions, similar dynamic load coefficients were obtained for similar test velocities at either Reynolds number condition. These findings impact many large launch vehicles, including the NASA Space Launch System series of vehicles. [ABSTRACT FROM AUTHOR]

Dryland ecosystems cover 40% of our planet's land surface, support billions of people, and are responding rapidly to climate and land use change. These expansive systems also dominate core aspects of Earth's climate, storing and exchanging vast amounts of water, carbon, and energy with the atmosphere. Despite their indispensable ecosystem services and high vulnerability to change, drylands are one of the least understood ecosystem types, partly due to challenges studying their heterogeneous landscapes and misconceptions that drylands are unproductive "wastelands." Consequently, inadequate understanding of dryland processes has resulted in poor model representation and forecasting capacity, hindering decision making for these at‐risk ecosystems. NASA satellite resources are increasingly available at the higher resolutions needed to enhance understanding of drylands' heterogeneous spatiotemporal dynamics. NASA's Terrestrial Ecology Program solicited proposals for scoping a multi‐year field campaign, of which Adaptation and Response in Drylands (ARID) was one of two scoping studies selected. A primary goal of the scoping study is to gather input from the scientific and data end‐user communities on dryland research gaps and data user needs. Here, we provide an overview of the ARID team's community engagement and how it has guided development of our framework. This includes an ARID kickoff meeting with over 300 participants held in October 2023 at the University of Arizona to gather input from data end‐users and scientists. We also summarize insights gained from hundreds of follow‐up activities, including from a tribal‐engagement focused workshop in New Mexico, conference town halls, intensive roundtables, and international engagements. Plain Language Summary: Drylands are landscapes with limited water availability, which cover 40% of Earth's land surfaces, support billions of humans, and play a substantial role in Earth's weather and climate systems. However, these ecosystems are under threat from droughts and heatwaves. They are also poorly understood because of challenges measuring their highly diverse vegetation types and interspersed vegetation cover and because of incorrect perceptions that they are unimportant "wastelands." These limitations make it challenging to manage their landscapes and quantify how drylands are driving Earth's weather and climate. NASA solicited proposals for a multi‐year field campaign, of which Adaptation and Response in Drylands (ARID) was one of two scoping studies selected. The ARID scoping study aims to design a plan for how NASA satellite, aircraft, and field instruments can be used to better understand dryland ecosystems and their response to change. A primary scoping goal is to engage with scientists and data‐users, especially those who manage land, to understand research and management priorities in drylands. Here, we discuss details of our meeting with over 300 scientists and data‐users in Tucson, AZ in October 2023. We also highlight feedback from our tribal‐focused workshop in New Mexico, conference town halls, and international meetings. Key Points: Adaptation and Response in Drylands (ARID) is a 1‐year scoping study for a multi‐year NASA Terrestrial Ecology dryland field campaignAn ARID workshop was held in Tucson, Arizona in October 2023 with more than 30 data end‐users and 300 scientists in attendanceFurther input from hundreds of researchers and end‐users was obtained through workshops, conference townhalls, and tribal engagement [ABSTRACT FROM AUTHOR]

This article discusses the history and significance of comets in our solar system. Comets have been observed and recorded throughout history, often being viewed as signs of good or bad times depending on the culture. The article also mentions notable comets that have gained public interest in recent years, such as Comet NEOWISE and Comet C/2022 E3 (ZTF). It introduces Comet C/2023 A3 Tsuchinshan-ATLAS, which was discovered in early 2023 and is expected to reach perihelion on September 27, 2024. The article provides tips for viewing comets and highlights the educational value of studying them. [Extracted from the article]

The National Aeronautics and Space Administration (NASA) has an ongoing Digital Transformation effort and to leverage and showcase the power of Digital Transformation, an effort is underway to develop an integrated, datacentric, model representing NASA's key process requirements. The task was divided into three phases: As Is modeling, Analysis, and To Be Planning. As part of this effort, a team has completed the first Phase I of the modeling task and is nearing completion of the second phase. This effort will capture the key elements as requirements, responsibilities, allocations, roles, products, and associated lifecycle elements. The scope of modeling included NASA's NPR 7120.5 (Project and Program Management), NPR 7123.1 (Systems Engineering) and NPRs 8705.2 (Risk classification for Robotic Missions) and 8705.4 (Human‐Rating Requirements for Space Missions). This paper will summarize the approach, scope, parsing patterns applied, metamodel, and associated workflows for the As‐Is modeling. It will also summarize the results and insights gleaned during that phase, including the review process. These insights have informed the analysis and will be discussed. The analysis modeling phase will also be summarized including how the stakeholders were engaged, how the common elements were handled and dispositioned, and will also describe some of the plans for the future of NASA NPDs and NPRs. [ABSTRACT FROM AUTHOR]

One of the key roles of National Aeronautics and Space Administration (NASA) is to help mitigate the risk and lower expenses associated with space exploration, science, and discovery to the point where industry and international partners are willing and able to profitably take on larger, more complex missions. To do this, the Agency must undertake a transformation to a more modern integrated Digital Engineering approach to mission definition and planning. This paper highlights NASA's journey in understanding what this Digital Engineering Transformation means for the Agency, the benefits of this transformation to human exploration definition and planning, and the benefits to the current Artemis campaign engineering capability portfolio. [ABSTRACT FROM AUTHOR]

To answer NASA’s call for a sensitive X-ray observatory in the 2030s, we present the High Energy X-ray Probe (HEX-P) mission concept. HEX-P is designed to provide the required capabilities to explore current scientific questions and make new discoveries with a broadband X-ray observatory that simultaneously measures sources from 0.2 to 80 keV. HEX-P’s main scientific goals include: 1) understand the growth of supermassive black holes and how they drive galaxy evolution; 2) explore the lower mass populations of white dwarfs, neutron stars, and stellar-mass black holes in the nearby universe; 3) explain the physics of the mysterious corona, the luminous plasma close to the central engine of accreting compact objects that dominates cosmic X-ray emission; and 4) find the sources of the highest energy particles in the Galaxy. These goals motivate a sensitive, broadband X-ray observatory with imaging, spectroscopic, and timing capabilities, ensuring a versatile platform to serve a broad General Observer (GO) and Guest Investigator (GI) community. In this paper, we present an overview of these mission goals, which have been extensively discussed in a collection of more than a dozen papers that are part of this Research Topic volume. The proposed investigations will address key questions in all three science themes highlighted by Astro2020, including their associated priority areas. HEX-P will extend the capabilities of the most sensitive low- and high-energy X-ray satellites currently in orbit and will complement existing and planned high-energy, time-domain, and multi-messenger facilities in the next decade.

Accurate structural information about forests, including canopy heights and diameters, is crucial for quantifying tree volume, biomass, and carbon stocks, enabling effective forest ecosystem management, particularly in response to changing environmental conditions. Since late 2018, NASA's Global Ecosystem Dynamics Investigation (GEDI) mission has monitored global canopy structure using a satellite Light Detection and Ranging (LiDAR) instrument. While GEDI has collected billions of LiDAR shots across a near-global range (between 51.6°N and >51.6°S), their spatial distribution remains dispersed, posing challenges for achieving complete forest coverage. This study proposes and evaluates an approach that generates high-resolution canopy height maps by integrating GEDI data with Sentinel-1, Sentinel-2, and topographical ancillary data through three machine learning (ML) algorithms: random forests (RF), gradient tree boost (GB), and classification and regression trees (CART). To achieve this, the secondary aims included the following: (1) to assess the performance of three ML algorithms, RF, GB, and CART, in predicting canopy heights, (2) to evaluate the performance of our canopy height maps using reference canopy height from canopy height models (CHMs), and (3) to compare our canopy height maps with other two existing canopy height maps. RF and GB were the top-performing algorithms, achieving the best 13.32% and 16% root mean squared error for broadleaf and coniferous forests, respectively. Validation of the proposed approach revealed that the 100th and 98th percentile, followed by the average of the 75th, 90th, 95th, and 100th percentiles (AVG), were the most accurate GEDI metrics for predicting real canopy heights. Comparisons between predicted and reference CHMs demonstrated accurate predictions for coniferous stands (R-squared = 0.45, RMSE = 29.16%). [ABSTRACT FROM AUTHOR]

The lunar south pole is a region of focused scientific and exploration interest, with several crewed and robotic missions to this region planned within the next decade. Understanding the mineralogy of the region is essential to inform landing site characterization and selection and provides the key context for interpreting samples and in situ observations. At high latitudes, extreme illumination conditions (high phase angles) can negatively impact the data quality of orbital instruments. This is especially true for passive near‐infrared spectrometers such as the Moon Mineralogy Mapper (M3) and the Kaguya Spectral Profiler, which measure the spectral properties of the surface using reflected sunlight. Using Moon Mineralogy Mapper data, we observed that the south polar region is associated with a detectable mafic signature consistent with the presence of pyroxenes. The strongest mafic signatures are associated with the South Pole—Aitken Basin, suggesting that impact melt and basin ejecta from the lower crust and upper mantle are present within this region. This observation is validated in several ways: (a) comparisons between M3 data acquired during different mission phases, (b) comparisons between multiple spectral parameters sensitive to the presence of mafic minerals, (c) comparisons between the north and south lunar polar regions, and (d) comparisons with publicly available Kaguya polar mineralogy maps and Lunar Prospector elemental abundances. We also investigate the nature of an anomalous high‐albedo region within 2–3° of the south pole observed in Lunar Orbiter Laser Altimeter reflectance data exhibiting a spatially conflicting apparent FeO abundance pattern between several data sets. Plain Language Summary: The lunar south pole region is a region of focused scientific and exploration interest, with several crewed and robotic missions to this region currently planned within the next decade and beyond. The rocks and minerals at the lunar south pole are very different from those encountered during the Apollo missions and will provide insight into a wide range of important science questions. It is important to understand the abundance and distribution of these different materials to effectively choose landing sites and plan surface science experiments and sampling targets. We combine several data sets from orbital satellites to determine the types and distribution of rocks across the south polar region. We see evidence for the presence of lower crust and upper mantle materials excavated by a nearby giant impact basin. Key Points: Moon Mineralogy Mapper data shows that the south polar region exhibits a mafic signature consistent with the presence of pyroxenesMafic signatures are spatially correlated with ejecta from the South Pole—Aitken Basin, which may be sampled by Artemis astronautsAn anomalous high‐albedo region within ∼3° of the south pole exhibits spatially conflicting apparent FeO abundance patterns between several data products [ABSTRACT FROM AUTHOR]

Abstract Dryland ecosystems cover 40% of our planet's land surface, support billions of people, and are responding rapidly to climate and land use change. These expansive systems also dominate core aspects of Earth's climate, storing and exchanging vast amounts of water, carbon, and energy with the atmosphere. Despite their indispensable ecosystem services and high vulnerability to change, drylands are one of the least understood ecosystem types, partly due to challenges studying their heterogeneous landscapes and misconceptions that drylands are unproductive “wastelands.” Consequently, inadequate understanding of dryland processes has resulted in poor model representation and forecasting capacity, hindering decision making for these at‐risk ecosystems. NASA satellite resources are increasingly available at the higher resolutions needed to enhance understanding of drylands' heterogeneous spatiotemporal dynamics. NASA's Terrestrial Ecology Program solicited proposals for scoping a multi‐year field campaign, of which Adaptation and Response in Drylands (ARID) was one of two scoping studies selected. A primary goal of the scoping study is to gather input from the scientific and data end‐user communities on dryland research gaps and data user needs. Here, we provide an overview of the ARID team's community engagement and how it has guided development of our framework. This includes an ARID kickoff meeting with over 300 participants held in October 2023 at the University of Arizona to gather input from data end‐users and scientists. We also summarize insights gained from hundreds of follow‐up activities, including from a tribal‐engagement focused workshop in New Mexico, conference town halls, intensive roundtables, and international engagements.

Ensuring the dependability of software before its public release is of utmost importance. Many software issues arise due to human errors made throughout the development process, highlighting the importance of addressing these errors early. It is crucial to incorporate testing resources at the beginning of development to minimize potential issues. Utilizing an approach that identifies modules susceptible to errors helps potential problems. With an understanding of the significance of precisely anticipating module failures, multiple automated solutions are already emerging. This work presents a refined software defect prediction model that utilizes a meta-heuristic optimization technique. The methodology integrates NASA’s data collection procedure, which involves data cleansing, reducing the dimensionality of features, and predicting defects. Principal Component Analysis (PCA) and Linear Discriminant Analysis (LDA) are used to decrease the feature dimensionality, while an Extreme Learning Machine (ELM) is utilized for forecasting defects. The ELM parameters, such as weight and biases, are ideally chosen using the suggested improved JAYA optimization (IMJAYA) method. The model’s validation involves assessing its accuracy, sensitivity, specificity, F1 score, and MCC metrics using a $10\times 5$ cross-validation. The model is verified using NASA datasets that consist of several classes, such as CM1, KC2, KC3, MC1, PC1, and JM1. The PCA-LDA+ IMJAYA-ELM model yields defect prediction accuracies of 95.73%, 98.08%, 94.87%, 96.23%, 97.10%, and 97.46% for the CM1, KC2, KC3, MC1, PC1, and JM1 datasets, respectively. The research outcomes show encouraging outcomes when using a meta-heuristic optimization technique with smaller feature sets for studies on predicting software defects.

The inspirational paper by Ash, Dowler, and Varsi in 1978, proposing to utilize in situ resources on Mars (ISRU) rather than bringing them from Earth, originated the field of Mars ISRU that has been the subject of research ever since. In this paper, we reviewed significant research reported on Mars ISRU since 1978 and reported briefly on accomplishments. We found that prior to 2014, progress on small tasks was sporadic and intermittent, always at low Technology Readiness Level (TRL). In 2014, the National Aeronautics and Space Administration (NASA) took a bold, imaginative, unprecedented step to fund a major project in Mars ISRU: the so-called "MOXIE" (Mars Oxygen In Situ Experiment), in which an oxygen production plant based on solid oxide electrolysis (SOEC) was developed, and finally demonstrated on Mars in 2022 and 2023. While MOXIE leaves behind it a wealth of accomplishments, there remains the need to close remaining gaps with additional laboratory and field work. Solid-oxide electrochemical cell (SOEC) technology has become a major area of worldwide investment for terrestrial energy and CO2 control. There is a very strong overlap between this terrestrial technology and Mars ISRU. NASA has already leveraged the terrestrial development work via MOXIE. NASA can leverage further advances with a comparatively small investment beyond 2023. Because NASA is engaged in a major program to return humans to the Moon, NASA's focus is on lunar ISRU. Unfortunately, the mission impact and return on investment for lunar ISRU does not compare to that for Mars ISRU. NASA's concept for Mars ISRU is futuristic, involving autonomous mining, transporting, and processing large amounts of Mars regolith. This might well occur long after initial human landings which could better profit in the near-term from MOXIE technology. By continuing further development of SOEC technology beyond MOXIE, while leveraging large investments in terrestrial applications, NASA can develop the Mars ISRU appropriate to nearer term human missions at modest investment. The goal of this paper is to place the relatively mature MOXIE technology advance and solid oxide electrolysis in general in perspective to the historical evolution of low TRL Mars ISRU technology. [ABSTRACT FROM AUTHOR]

The televisual image has played a key role in the first fifty years of human spaceflight and lunar exploration by the National Aeronautics and Space Administration (NASA). As multiple national space agencies and private entities prepare to return humans once again to the surface of the moon as a precursor to eventual planned missions to Mars, television will continue to deeply shape the perception and politics of human spaceflight. This paper presents a history of the televisual image in human spaceflight through analysis of contemporaneous documentary evidence such as spaceflight transcripts and space agency press kits, with a focus also on the technical developments underpinning the broadcasts. The analysis commences with NASA's Apollo missions of the 1960s through to the International Space Station (ISS) era. These televisual images have deep cultural currency but are also fragile and present moments of risk for the agencies involved. [ABSTRACT FROM AUTHOR]

Human beings are adapted to dry land and standard atmosphere, and to investigate other areas of the globe such as the sea and the air, let alone Space, we need the multivalent support of numerous machine interventions. Space architect Brent Sherwood explains the huge problems that must be overcome to satisfy our longing to explore extraterrestrial worlds and become truly posthuman as we travel and live beyond the confines of our planet. [ABSTRACT FROM AUTHOR]

Guest‐Editor Mark Garcia takes us on a spatial journey through some of the notions and precedents of spaceships and spacecraft, their fictive and architectural precursors and current conceptual preoccupations. The contexts these new posthuman architectures and posthumans will have to occupy, endure and travel through are mind‐boggling in their varied complexity. [ABSTRACT FROM AUTHOR]

Architect and advocate of speculative posthuman ecological design Steven Hutt offers new thoughts on the integration of wildlife into our architectures and cities. Awareness of the 'feral' as a design tool, the push and pull between indigenous and non‐indigenous species, and even old ideas of colonialism are all agents in this new posthuman landscape. There are many aspects of this often anti‐ anthropocentric worldview across a variety of scales. Might zoo animals one day be able to decide how we look at them and observe their habits? [ABSTRACT FROM AUTHOR]

The article discusses various astronomical discoveries and events that occurred in 2023 and provides a preview of what to expect in 2024. Some of the highlights from 2023 include the verification of gravitational waves, the return of the OSIRIS-Rex spacecraft from its mission to Asteroid Bennu, the discovery of a planet in the habitable zone of Proxima Centauri, and the launch of lunar missions by Russia, India, and China. Looking ahead to 2024, there will be several celestial events to look forward to, as well as planned space missions by NASA and other space agencies, including the Artemis missions and the Europa Clipper mission. [Extracted from the article]

Whilst Indigenous autonomy is generally regarded as something positive, the existence of human rights abuses inside Indigenous communities has received relatively little attention in legal scholarship. Human rights abuses include severe violations of religious freedom, particularly of converts away from the traditional religion. Based on original empirical field research conducted in the Nasa Indigenous territories in the southwestern highlands of Colombia (2010–2017), I discuss the challenge of balancing the right to self-determination of Indigenous Peoples and the individual human rights of people living in Indigenous territories, particularly religious minorities. I show this has implications for the analysis of “minority in the minority” situations beyond the context of Latin America.

Serwis internetowy YouTube oferuje swoim użytkownikom opcję bezpłatnego udostępniania treści w postaci filmów wideo. Jedną z grup twórców, którzy korzystają z takiej możliwości są popularyzatorzy nauki. W artykule dokonano charakterystyki oraz analizy porównawczej pod względem ilościowym i jakościowym trzech wybranych kanałów popularyzujących naukę z dziedziny astronomii: Astrofaza, PBS Space Time oraz NASA. Badania wykonano metodą analizy zawartości mediów oraz statystyczną. Przedmiotem badania były filmy oraz zapisy zakończonych transmisji na żywo opublikowanych na uwzględnionych kanałach w okresie od 1 do 31 marca 2023 roku. W ramach dokonanej analizy ustalono podobieństwa i różnice dotyczące wybranych kanałów.

BACKGROUND: In the early days of the National Aeronautics and Space Administration (NASA), medicine in support of the astronauts was led by military experts from the U.S. Air Force as well as experts from the U.S. Navy and U.S. Army. In the early years, a physician with expertise in aerospace medicine was assigned to the Space Task Group and then to NASA. One of these individuals was Dr. Stanley White, a U.S. Air Force physician. To capture more of the early space medicine pioneers, a contract was established between the National Library of Medicine and the principal investigator at the University of Cincinnati to conduct a series of interviews with these early pioneers. An interview with Dr. White took place in his home while he was in hospice care. This audiotaped interview and other written and oral histories within NASA archives and the literature were reviewed to support this work. A series of questions were prepared for the interaction with Dr. White. These questions provided further clarification on his background and contribution. Responses to questions elicited open-ended discussion. The conversation provided a historical summary of Dr. White’s contribution to NASA as one of its first flight surgeons. [ABSTRACT FROM AUTHOR]

During the last decades, freely available GDEMs, such as ASTER, SRTM, and AW3D30, have been widely used in many applications such as for environmental, spatial analysis, research in geomorphology, hydrology, etc. However, these available GDEMs suffer from various limitations. In order to enhance the quality and accuracy of GDEMs, several GDEMs have been merged or reprocessed using a more rigorous method to develop new GDEMs. The advent of these new improvised GDEMs has advanced their applications. Unfortunately, there are very limited studies that focus on the comprehensive and systematic evaluation of the quality of improvised GDEM. Therefore, this study examines the vertical accuracy of three freely available improvised GDEMs (MERIT, NASA, and EarthEnv GDEMs) over the northern region of Peninsular Malaysia using 7757 GNSS points and two reference model, i.e., TanDEM-X DEM 12m resolution and local airborne IFSAR DEM 5m resolution. The accuracy assessments have been performed over three different land covers (urban, non-forest, and forest areas) to evaluate the impact of different land covers on the GDEM's accuracy. Since SRTM DEM is the primary data input in the improvised GDEM, this GDEM is also considered to identify the performance of the new improvised GDEMs. Comparison with GNSS points shows that the accuracy of MERIT DEMs outperforms SRTM DEM and other GDEMs with RMSE of ±2.668m, followed by NASA (±3.656m), SRTM (±5.666m), and EarthEnv (±5.948m). The vertical accuracy of DEM varies with different land cover conditions. Comparison with TanDEM-X and IFSAR DEM shows that all tested GDEMs' accuracy is high over a nonforest area, followed by urban area, and worse over forest area. Overall, the tested GDEM shows only a slight improvement compared to the SRTM. However, these results will help users in selecting the optimum DEM for any application. [ABSTRACT FROM AUTHOR]

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Copyright of Revista Foco (Interdisciplinary Studies Journal) is the property of Revista Foco and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

NASA's ITS_LIVE project delivers information on global glacier dynamics and provides historical context for climate change with a record of how every glacier in the world has evolved over decades of satellite observation. To handle petabytes of data in the satellite archives and a constant influx of new observations, the project has adopted a cloud-native approach that is scalable, performant, user friendly, and embraces transparent and collaborative code development. As every discipline of Earth science is being transformed by a new era of remote sensing and cloud computing, ITS_LIVE offers a progressive approach to maximizing scientific advancements through open science. [ABSTRACT FROM AUTHOR]

Over the past few years, stringent environmental requirements and the need for increased overall efficiency have forced designers to bring turbomachine components closer to their operating limits. To address lifespan issues, costly redesign operations are thus unavoidable. These operations face many roadblocks, especially when they are triggered by nonlinear phenomena for which there exists no design guidelines. For aircraft engine blades, the handling of nonlinear structural interactions is a major challenge. This works proposes a proof of concept for the redesign of compressor blades undergoing structural contact interactions at the blade-tip/casing interface. The redesign process involves the modeling of an existing input blade, followed by a shape update based on an iterative optimization algorithm. A two-way modeling method is proposed to parameterize the input blade and generate a computer-aided design model from blade parameters describing several conical blade sections. The fidelity of the parameterized blade with respect to the input blade is assessed for the NASA blades rotor 37 and rotor 67. A high fidelity is observed with respect to geometric and dynamic characteristics. The modeling method is fully compatible with an iterative redesign process: it is applied to the redesign of rotor 37 to increase its robustness to contact interactions. [ABSTRACT FROM AUTHOR]

The Transiting Exoplanet Survey Satellite (TESS) is a Massachusetts Institute of Technology‐led NASA Explorer‐class mission planned to spend 2 years discovering transiting exoplanets by an all‐sky survey. The observatory contains four wide field‐of‐view camera systems for a total of 16.8 Megapixel, low‐noise, low‐power CCD detectors. Now over 5 years beyond its launch date and 10 years after the CCD design tape out, we report on our approach for managing camera system development, with particular emphasis on the design, fabrication, and testing of the silicon detectors, developed on 200‐mm high‐resistivity wafer substrates. Finally, we present implications of the CCD manufacture observed in the on‐orbit performance. [ABSTRACT FROM AUTHOR]