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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 559 records · Page 31
All sourcesNASA NTRSDOE OSTI
NASA NTRS2018

Improving Global Precipitation Product Access at the GES DISC

The NASA Goddard Earth Sciences Data and Information Services Center (GES DISC) has been actively and continually engaged in improving the access to and use of Global Precipitation Measurement (GPM), Tropical Precipitation Measuring Mission (TRMM), and other precipitation data, including the following new services and ongoing development activities: Updates on GPM products and data services; New features in Giovanni; Ongoing development activities; Precipitation product and service outreach activities.

Ostrenga, D.↗
NASA NTRS2018

Data Tips: Learn How to Discover, Access and Analyze NASA GES DISC Data

At the NASA Goddard Earth Sciences Data and Information Services (GES DISC), we strive to simplify data discovery and data access to our wide range of global climate data, concentrated primarily in the areas of atmospheric composition, atmospheric dynamics, global precipitation, solar irradiance, and several modeling data sets related to land surface hydrology. To help meet user needs, we will demonstrate how you can use the GES DISC knowledge-base resources (HowTo's) and we also encourage community contributions.

data tips↗
NASA NTRS2018

The Multiple Access Testbed for Research in Innovative Communications Systems (MATRICS)

NASA is presently in the planning stages for the next generation earth relay architecture which will transition to Ka-band services in a new, potentially commercially-driven architecture, by 2040. To assess the performance of various technologies and architectures, the Multiple Access Testbed for Research in Innovative Communications Systems (The MATRICS), is being developed to offer a flexible emulation platform for system-level architecture and technology assessments of candidate next generation Ka-band relay and user terminal solutions. In this paper, we describe the architecture and setup of the MATRICS, which is presently housed in GRC’s 25-ft anechoic chamber.

next generation relay↗
NASA NTRS2019

Using UMM-Var and E2E to Improve the User Experience for Accessing NASA EOSDIS Data Sets

The UMM-Variables (Var) Metadata Model has been evolved to support an End-to-End Services (E2E) capability, which enables variable level subsetting, data transformation, and data reformatting. This talk will discuss what is new with the model, how users can get their metadata ready for the E2E capability, and include a demo of how the model is being used to drive and improve the user experience in Earthdata Search Client when accessing EOSDIS data sets.

Metadata Modeling↗
NASA NTRS2019

NASA's Space Launch System: Deep Space Access for CubeSats

NASA is embarking on a new generation of missions to the Moon, known as the Artemis program. The Agency’s new super heavy-lift launch vehicle, the Space Launch System (SLS), is a critical enabling capability for these efforts, which will serve as a proving ground for future crewed expeditions to Mars. SLS is designed to return astronauts to the Moon in the Orion spacecraft and to launch more mass and provide more volume for critical payloads than commercially available vehicles, giving NASA a unique asset for deep space exploration. When performance margin and volume is available, as it is on the first flight, Artemis I (previously Exploration Mission-1), SLS can offer CubeSats access to deep space, beyond Earth’s orbit. The Artemis I flight has 13 6U (14 kg) CubeSats manifested, and the Program is currently accepting proposals for 6U and 12U payloads for the Artemis II flight through the agency’s CubeSat Launch Initiative (CSLI) program. Proposals from U.S.-based payload developers to fly on Artemis II will be accepted through CSLI until November 4, 2019. When ridesharing on SLS deep space missions, CubeSats must demonstrate they will not interfere with primary mission objectives. The 13 Artemis I CubeSats that hail from industry, academia, NASA and its international partners represent an array of exciting deep space science investigations and technology demonstrations that may help inform future Artemis missions. The initial SLS Block 1 vehicle for the Artemis I flight is fully manufactured; several elements are complete and have been delivered to the Exploration Ground Systems (EGS) Program at Kennedy Space Center (KSC), which has responsibility for integrating and launching the SLS and Orion stack. Completed elements of the Artemis I vehicle include the Orion Stage Adapter (OSA), which houses the 13 Artemis I CubeSats. With the Artemis I flight hardware and software nearing completion, work is in progress for the second Block 1 launcher, designated for the crewed Artemis II flight. Hardware is being manufactured for every element of the Artemis II vehicle. In this paper, the author will review the status of the Artemis I vehicle and the payloads manifested for the initial flight. Information on the Secondary Payload Deployment System (SPDS) that the SLS Program provides to payload developers will also be included.

Creech, Stephen D.↗
NASA NTRS2019

Streamlining Access to Satellite Level 2 Data

Users wishing to work with Satellite Level 2 data often have to overcome many hurdles: various file format standards, large files containing hundreds of variables, inconsistent presentation of geospatial and temporal variables, inhomogeneous data structures, and nonlinear spatial geometry. The Level 2 Subsetting service at NASA Goddard Earth Sciences Data and Information Services Center (GES DISC) has many options to streamline and simplify user access to this data. In this presentation, we will detail the capabilities of this service and demonstrate how users can incorporate it into their Level 2 data workflow.

Huwe, Paul↗
NASA NTRS2020

Accessibility Design and Operational Considerations in the Development of Urban Aerial Mobility Vehicles and Networks

Urban aerial mobility vehicles and networks have recently gained considerable interest in the aviation community. These small, short-range vehicles with all-electric or hybrid-electric propulsion systems, tailored to metropolitan aerial transportation needs, promise to radically change passenger mobility and cargo distribution in cities. Accessibility issues have not been a major consideration in UAM vehicle and network discussions to date. This paper seeks to help change that.

Young, Larry A.↗
NASA NTRS2020

The Roughness Properties of Small Ice-Bearing Craters at the South Pole of the Moon: Implications for Accessing Fresh Water Ice in Future Surface Operations

The lunar poles provide a fascinating thermal environment capable of cold-trapping water ice on geologic timescales [1]. While there have been many observations indicating the presence of water ice at the lunar surface [e.g., 2–4], it is still not clear when this ice was delivered to the Moon. The timing of volatile dep-osition provides important constraints on the origin of lunar ice because different delivery mechanisms have been active at different times throughout lunar history. We previously found that some small (<10 km) cra-ters at the south pole of the Moon have morphologies suggestive of relatively young ages, on the basis of crisp crater rims [5]. These craters are too small to date with robust cratering statistics [5], but the possibility of ice in young craters is intriguing because it suggests that there is some recent and perhaps ongoing mechanism that is delivering or redistributing water to polar cold traps. Therefore, understanding if these small, ice-bear-ing craters are indeed young is essential in understand-ing the age and source of volatiles on the Moon. Here we take a new approach to understand the ages of these small polar cold traps: analyzing the roughness properties of small ice-bearing craters. It is well under-stood that impact crater properties (e.g., morphology, rock abundance, and roughness) evolve with time due to a variety of geologic and space-weathering processes [6–11]. Topographic roughness is a measurement of the local deviation from the mean topography, providing a measurement of surface texture, and is a powerful tool for evaluating surface evolution over geologic time [e.g., 11–14]. In this study we analyze the roughness of southern lunar craters (40°S–90°S) from all geologic eras, and determine how the roughness of small (<10 km) ice-bearing craters compare. We discuss the implications of the ages of ice-bearing south polar craters, and potential strategies for accessing fresh ice on the Moon.

Deutsch, Ariel N.↗
NASA NTRS2019

Hybrid Transportation System Integrated Trajectory Design and Optimization for Mars Landing Site Accessibility

NASA’s Mars Study Capability Team continues the agency’s efforts to study and refine the nation’s plan to field a sustainable human Mars campaign. One of the primary open issues left unanswered during previous analysis cycles was the uncertainty of the impact to the vehicle performance requirement to deliver crew and cargo to the same landing site across multiple mission opportunities. The Mars Study Capability Team has recently developed an integrated trajectory optimization and system closure model to solve the complex interplanetary trajectory optimization using both low-thrust and high-thrust maneuvers. This paper demonstrates the capability of this new integrated trajectory design and optimization method as it applies to the landing site accessibility problem for the Hybrid transportation architecture. The results showed that the current vehicle is capable of reaching up to +20 degree latitude and down to -20 degree latitude in every mission opportunity from 2033 to 2052. However, reaching latitudes beyond +/- 20 required more propellant than the spacecraft is currently designed to carry for many of the mission opportunities.

Chai, Patrick R.↗
NASA NTRS2019

Workforce for the Future Development of Space Access Vehicles

The development of advanced vehicles that will travel between planetary surfaces with atmospheres and space requires the availability of experimental and computational capabilities that accomplish the research leading to new technologies and the development, test, and evaluation (RDT&E) of new flight systems. The United States is at risk of not having the required RDT&E workforce – qualified and in sufficient numbers – in place and ready to meet the future market’s commercial and defense needs. Systemic challenges include uncertain Federal budgets that limit and interrupt government research and development, the projectized nature of new space access systems that drive boom/bust cycles, an aging aerospace workforce (compounded by a mid-age demographic gap), limited to declining investment in sustaining and advancing experimental and computational tools infrastructure, lack of standards for sharing (and leveraging) data, dramatically changing technologies, changing social norms, and potentially large increases in commercial market needs. Flight systems have mission-based trajectories to and from space and designers must ensure risk is properly assessed across the entire trajectory. Thus, physics questions must be answered at each stage of flight, which requires a suite of experimental and computational tools. The RDT&E workforce utilizing these tools include subject matter experts from the producers, interested in acquiring data and information on the product, and from the capabilities being utilized, interested in addressing the product customer’s needs (providing robust data collection techniques, data quality, timeliness – available when needed, efficient with cost management, and teaming on data analysis). This requires a range of skills – in addition to aerospace, other engineers, and software developers, a highly trained and certified craft and technician workforce is critical to future success. This paper will present a human resources construct that addresses the system of needs for people – including, but more than just technical skills and an application of that construct in the hypersonic Test and Evaluation (T&E) community. This is part of a larger AIAA effort to document challenges and associated best practices for the aerospace RDT&E workforce.

Steven C Dunn↗
NASA NTRS2020

NASA Access 2 Space Workshop: Summary Report: Increased Science Return through Rideshare

This report summarizes the Access to Space (A2S) Workshop held on February 25-27, 2020 at the Johns Hopkins University Applied Physics Laboratory (APL) and hosted by NASA’s Science Mission Directorate (SMD). This workshop solicited community input on the creation and management of an ESPA-class1payload pipeline for NASA SMD launches. The workshop brought together roughly 180 participants including scientists, engineers, instrument developers, launch providers, and policy makers across NASA centers, government agencies, commercial industry, research institutes, and academia.

ESPA-Class Spacecraft↗
NASA NTRSDate not supplied

Langley Automated Sensor Inter-calibration System (LASICS): Open Access Tools for Satellite Imager Inter-Calibration

Satellite imager calibration teams are tasked with maintaining stable measurement records to facilitate reliable monitoring of geophysical parameters and ensure dependable input for weather forecast models. Satellite imagers are neither uniformly calibrated nor radiometrically scaled to a common reference. Consistent inter-calibration between various earth-orbiting satellite imager pairs is a critical step in the creation of seamless earth-scene reflectance data records over time for input to higher level algorithms that retrieve earth system climate-sensitive properties. Each imager inherently by virtue of its optics (and associated properties like Spectral Response etc.) will have a unique measurement of the same earth-scene reflected signal. A key part of this is the identification and prediction of events where the imager pairs from their respective earth-orbits view the same stable terrestrial targets with nearly identical viewing and solar geometry. Langley Automated Sensor Inter-calibration System (LASICS) will provide the Earth remote sensing community with a foundation for the harmonization of these remote sensing records by the development of an intuitive, user-friendly, interactive web-based open access service that will leverage, an existing extensive and ever-growing database of earth-imager channel spectral response functions, on-demand capabilities for computation and visualization of spectral band adjustment factors using a variety of external hyper-spectral earth observation sources (e.g. SCIAMACHY, GOME-2 for VIS and IASI, AIRS for IR) and a variety of Solar Irradiance Spectra.

Arun Gopalan↗
NASA NTRS2003

Design of an event-driven random-access-windowing CCD-based camera

Commercially available cameras are not designed for the combination of single frame and high-speed streaming digital video with real-time control of size and location of multiple regions-of-interest (ROI). A new control paradigm is defined to eliminate the tight coupling between the camera logic and the host controller. This functionality is achieved by defining the indivisible pixel read out operation on a per ROI basis with in-camera time keeping capability. This methodology provides a Random Access, Real-time, Event-driven (RARE) camera for adaptive camera control and is well suited for target tracking applications requiring autonomous control of multiple ROIs. This methodology additionally provides for reduced ROI read out time and higher frame rates compared to the original architecture by avoiding external control intervention during the ROI read out process.

Ortiz, Gerardo G.↗
NASA NTRS2019

A technology architecture for accessing the oceans of icy worlds

The icy moon oceans beckon with ingredients that potentially may harbour extant life. Beginning with the Galileo and Cassini missions, measurements have revealed the presence of global oceans under the icy crust of several moons of Jupiter and Saturn. Among those moons, Europa and Enceladus have their ocean in contact with the rocky core, providing an environment similar to the conditions existing on the terrestrial seafloor where life has developed at hydrothermal vents. A detailed trade space study was conducted to develop a technology architecture defining a system that would access an icy moon’s ocean. This paper outlines the architecture with specific consideration to the power source necessary to drive the system.

Smith, Miles↗
NASA NTRSDate not supplied

Australian Bushfire in 2020: Accessing MERRA-2 Data in GES DISC Remotely through OPeNDAP & Calculating Statistics with Python3

The evolution and transport of thick haze from the 2020 Australian bushfire is tracked using the NASA Modern-Era Retrospective analysis for Research and Applications version 2 (MERRA-2) data archived at the NASA GES DISC data center. The MERRA-2 provides global data at 0.5 x 0.625 spatial resolution since the year 1980. In this use case, with xarray, a python3 library, we remotely accessed the hourly aerosol optical depth (AOD) and PM2.5 data through the OpeNDAP service provided by GES DISC. We also derived weekly data from hourly ones.

Xiaohua Pan↗