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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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NASA NTRS2016

Post Launch Calibration and Testing of the Advanced Baseline Imager on the GOES-R Satellite

The Geostationary Operational Environmental Satellite R (GOES-R) series is the planned next generation of operational weather satellites for the United State's National Oceanic and Atmospheric Administration. The first launch of the GOES-R series is planned for October 2016. The GOES-R series satellites and instruments are being developed by the National Aeronautics and Space Administration (NASA). One of the key instruments on the GOES-R series is the Advance Baseline Imager (ABI). The ABI is a multi-channel, visible through infrared, passive imaging radiometer. The ABI will provide moderate spatial and spectral resolution at high temporal and radiometric resolution to accurately monitor rapidly changing weather. Initial on-orbit calibration and performance characterization is crucial to establishing baseline used to maintain performance throughout mission life. A series of tests has been planned to establish the post launch performance and establish the parameters needed to process the data in the Ground Processing Algorithm. The large number of detectors for each channel required to provide the needed temporal coverage presents unique challenges for accurately calibrating ABI and minimizing striping. This paper discusses the planned tests to be performed on ABI over the six-month Post Launch Test period and the expected performance as it relates to ground tests.

Instrument↗

NASA NTRS2016

Post Launch Calibration and Testing of the Advanced Baseline Imager on the GOES-R Satellite

The Geostationary Operational Environmental Satellite R (GOES-R) series is the planned next generation of operational weather satellites for the United States National Oceanic and Atmospheric Administration. The first launch of the GOES-R series is planned for October 2016. The GOES-R series satellites and instruments are being developed by the National Aeronautics and Space Administration (NASA). One of the key instruments on the GOES-R series is the Advance Baseline Imager (ABI). The ABI is a multi-channel, visible through infrared, passive imaging radiometer. The ABI will provide moderate spatial and spectral resolution at high temporal and radiometric resolution to accurately monitor rapidly changing weather. Initial on-orbit calibration and performance characterization is crucial to establishing baseline used to maintain performance throughout mission life. A series of tests has been planned to establish the post launch performance and establish the parameters needed to process the data in the Ground Processing Algorithm. The large number of detectors for each channel required to provide the needed temporal coverage presents unique challenges for accurately calibrating ABI and minimizing striping. This paper discusses the planned tests to be performed on ABI over the six-month Post Launch Test period and the expected performance as it relates to ground tests.

Instrument↗

NASA NTRS2016

Satellite-Surface Perspectives of Air Quality and Aerosol-Cloud Effects on the Environment: An Overview of 7-SEAS BASELInE

The objectives of 7-SEASBASELInE (Seven SouthEast Asian Studies Biomass-burning Aerosols and Stratocumulus Environment: Lifecycles and Interactions Experiment) campaigns in spring 2013-2015 were to synergize measurements from uniquely distributed ground-based networks (e.g., AERONET (AErosol RObotic NETwork)), MPLNET ( NASA Micro-Pulse Lidar Network)) and sophisticated platforms (e.g.,SMARTLabs (Surface-based Mobile Atmospheric Research and Testbed Laboratories), regional contributing instruments), along with satellite observations retrievals and regional atmospheric transport chemical models to establish a critically needed database, and to advance our understanding of biomass-burning aerosols and trace gases in Southeast Asia (SEA). We present a satellite-surface perspective of 7-SEASBASELInE and highlight scientific findings concerning: (1) regional meteorology of moisture fields conducive to the production and maintenance of low-level stratiform clouds over land; (2) atmospheric composition in a biomass-burning environment, particularly tracers-markers to serve as important indicators for assessing the state and evolution of atmospheric constituents; (3) applications of remote sensing to air quality and impact on radiative energetics, examining the effect of diurnal variability of boundary-layer height on aerosol loading; (4) aerosol hygroscopicity and ground-based cloud radar measurements in aerosol-cloud processes by advanced cloud ensemble models; and (5) implications of air quality, in terms of toxicity of nanoparticles and trace gases, to human health. This volume is the third 7-SEAS special issue (after Atmospheric Research, vol. 122, 2013; and Atmospheric Environment, vol. 78, 2013) and includes 27 papers published, with emphasis on air quality and aerosol-cloud effects on the environment. BASELInE observations of stratiform clouds over SEA are unique, such clouds are embedded in a heavy aerosol-laden environment and feature characteristically greater stability over land than over ocean, with minimal radar surface clutter at a high vertical spatial resolution. To facilitate an improved understanding of regional aerosol-cloud effects, we envision that future BASELInE-like measurement modeling needs fall into two categories: (1) efficient yet critical in-situ profiling of the boundary layer for validating remote-sensing retrievals and for initializing regional transport chemical and cloud ensemble models; and (2) fully utilizing the high observing frequencies of geostationary satellites for resolving the diurnal cycle of the boundary layerheight as it affects the loading of biomass-burning aerosols, air quality and radiative energetics.

AERONET↗

NASA NTRS2018

Core/Combustor-Noise Baseline Measurements for the DGEN Aeropropulsion Research Turbofan

Contributions from the combustor to the overall propulsion noise of civilian transport aircraft are starting to become important due to turbofan design trends and advances in mitigation of other noise sources. Future propulsion systems for ultra-efficient commercial air vehicles are projected to be of increasingly higher bypass ratio from larger fans combined with much smaller cores, with ultra-clean burning fuel-flexible combustors. Unless effective noise-reduction strategies are developed, combustor noise is likely to become a prominent contributor to overall airport community noise in the future. The new NASA DGEN Aeropropulsion Research Turbofan (DART) is a cost-efficient testbed for the study of core-noise physics and mitigation. This paper describes the recently completed DART core/combustor-noise baseline test in the NASA GRC Aero-Acoustic Propulsion Laboratory (AAPL). Acoustic data were simultaneously acquired using the AAPL overhead microphone array in the engine aft quadrant farfield, a single midfield microphone, and two semi-infinite-tube unsteady pressure sensors at the core-nozzle exit. Combustor-noise components of measured total-noise signatures were educed using a two-signal source-separation method and are found to occur in the expected frequency range. The acoustic data compare well with results from a limited 2014 feasibility test and will serve as a high-quality baseline for future research using the DART. The research described herein is aligned with the NASA Ultra-Efficient Commercial Transport strategic thrust and is supported by the NASA Advanced Air Vehicle Program, Advanced Air Transport Technology Project, under the Aircraft Noise Reduction Subproject.

Turbomachinery Noise↗

NASA NTRS2018

Core/Combustor-Noise Baseline Measurements for the DGEN Aeropropulsion Research Turbofan

Contributions from the combustor to the overall propulsion noise of civilian transport aircraft are starting to become important due to turbofan design trends and advances in mitigation of other noise sources. Future propulsion systems for ultra-efficient commercial air vehicles are projected to be of increasingly higher bypass ratio from larger fans combined with much smaller cores, with ultra-clean burning fuel-flexible combustors. Unless effective noise-eduction strategies are developed, combustor noise is likely to become a prominent contributor to overall airport community noise in the future. The new NASA DGEN Aeropropulsion Research Turbofan (DART) is a cost-efficient testbed for the study of core-noise physics and mitigation. This paper describes the recently completed DART core/combustor-noise baseline test in the NASA GRC Aero-Acoustic Propulsion Laboratory (AAPL). Acoustic data was simultaneously acquired using the AAPL overhead microphone array in the engine aft quadrant far field, a single midfield microphone, and two semi-infinite-tube unsteady pressure sensors at the core-nozzle exit. Combustor-noise components of measured total-noise signatures were educed using a two-signal source-separation method and are found to occur in the expected frequency range. The acoustic data compares well with results from a limited 2014 feasibility test and will serve as a high-quality baseline for future research using the DART. The research described herein is aligned with the NASA Ultra-Efficient Commercial Transport strategic thrust and is supported by the NASA Advanced Air Vehicle Program, Advanced Air Transport Technology Project, under the Aircraft Noise Reduction Subproject.

Aeroacoustics↗

NASA NTRS2019

HabEx Baseline Optical Telescope Assembly

The Habitable Exoplanet Observatory Mission (HabEx) will image and spectroscopically characterize planetary systems in the habitable zone around nearby sun-like stars. Additionally, HabEx will perform a broad range of general astrophysics science enabled by 100 to 2500 nm spectral range and 3 x 3 arc-minute FOV. Critical to achieving the HabEx science goals is a large, ultra-stable telescope. The baseline HabEx telescope is a 4-m off-axis unobscured three-mirror-anastigmatic design with diffraction limited performance at 400 nm and wavefront stability of picometers per mK. These specifications are driven by science requirements. STOP (structural thermal optical performance) analysis predicts that the baseline telescope’s opto-mechanical design meets its specified performance tolerances.

Stahl, H Philip↗

NASA NTRS2019

Technology Development Roadmap for Habitable-Zone Exoplanet Observatory (HabEx) Baseline 4-M Primary Mirror

The Habitable Exoplanet Observatory (HabEx) is one of four mission concepts under study for the 2020 Astrophysics Decadal Survey. Its goal is to directly image and spectroscopically characterize planetary systems in the habitable zone around nearby sun-like stars. Additionally, HabEx will perform a broad range of general astrophysics science enabled by 115 to 2500 nm spectral range and 3 x 3 arc-minute FOV. Critical to achieving the HabEx science goals is a large, ultra-stable UV/Optical/Near-IR (UVOIR) telescope. The baseline HabEx telescope is 4-meter off-axis unobscured, diffraction limited at 400 nm with wavefront stability on the order of a few 10s of picometers. The technology readiness level (TRL) to manufacture and test the HabEx baseline primary mirror is assessed to be at TRL-6 for all but two TRL-4 technologies: 1) non-destructive process to quantify CTE homogeneity of a 4-m mirror substrate with a spatial sampling of at least 100 x 100 to better than +/- 1 ppb/K; and, 2) process to quantify self-weight gravity deflection to better than 4-nm rms over a 100 x 100 spatial sampling. This paper reviews the technology needs to manufacture the HabEx primary mirror, assesses their TRL and proposes a roadmap to mature the two remaining technologies to TRL-6.

Space Telescope Technology↗

NASA NTRS2019

Summary DSG-RQMT-004, Gateway Electromagnetic Environmental Effects (E3) Requirements Document, Initial Baseline

The Baseline Readiness Review presentation for DSG-RQMT-004 at a high level summarizes the differences between the originating standards (publicly available) and the Gateway-tailored standards (publicly available per DAA 72653). All data in the presentations are either derived from either MIL-STD-461G, SSP 30237, or SL-E-002 (Shuttle EMI spec). The Baseline Readiness Review presentation identifies why a tailored standard was necessary for Gateway (summarizes the changes made from the originating standard). Communicating this information should lead to IP and vendor Level 3 responders proposing substitute standards more in line with the Gateway requirements.

MIL-STD-464↗

NASA NTRS2020

HabEx Baseline Telescope: Design & Predicted Performance

Habitable Exoplanet Observatory Mission (HabEx) will image & spectroscopically characterize planetary systems in the habitable zone around nearby sun-like stars. Additionally, HabEx will perform a broad range of general astrophysics science enabled by a 150 to 1700 nm spectral range and 3 x 3 arc-minute FOV. Critical to achieving the HabEx science goals is a large, ultra-stable telescope. The baseline HabEx telescope is a 4-m off-axis unobscured three-mirror-anastigmatic design with diffraction limited performance at 400 nm and wavefront stability of picometers per mK. These specifications are driven by science requirements. STOP (structural thermal optical performance) analysis predicts that the baseline telescope’s opto-mechanical design meets its specified performance tolerances.

Stahl, H. Philip↗

NASA NTRS2019

Summary DSG-RQMT-007, Initial Baseline

The Baseline Readiness Review presentations for DSG-RQMT-007 at a high level summarizes the differences between the originating standards (publicly available) and the Gateway-tailored standards (publicly available per DAA 72653). All data in the presentations are either derived from either MIL-STD-461G, SSP 30237, or SL-E-002 (Shuttle EMI spec). The Baseline Readiness Review presentation identifies why a tailored standard was necessary for Gateway (summarizes the changes made from the originating standard). Communicating this information should lead to IP and vendor Level 3 responders proposing substitute standards more in line with the Gateway requirements.

MIL-STD-461↗

NASA NTRS2020

Stowage Assessment of the Common Habitat Baseline Variants

This paper performs a stowage assessment of the four baseline variants of the Common Habitat, a SLS-derived long duration, multi-mission habitat. The Common Habitat can be utilized as a lunar surface outpost, a Mars surface outpost, or an in-space habitat for Mars transit flights. The paper will discuss the stowage philosophy applied to all baseline variants of the Common Habitat and will discuss the approaches taken to domain-specific stowage, bulk stowage, and fluid and gas stowage. Water and air stowage for the closed loop ECLS subsystem is described across the four variants. Stowage of other supplies, consumables, and equipment is also described across the four variants and based on logistics sizing studies, a self-contained mission endurance is predicted for each variant – e.g. how long a mission each can support without a docked logistics module. Finally, follow-on assessments, including a habitability evaluation, are discussed along with specific stowage issues relevant to these assessments.

Deep space habitat↗

NASA NTRS2021

The Origins Space Telescope: Trades and Decisions Leading to the Baseline Mission Concept

Infrared↗

NASA NTRS2021

The Origins Space Telescope: Baseline Mission Concept

The Origins Space Telescope will trace the history of our origins from the time dust and heavy elements permanently altered the cosmic landscape to present-day life. How did galaxies evolve from the earliest galactic systems to those found in the Universe today? How do habitable planets form? How common are life-bearing worlds? To answer these alluring questions, Origins will operate atmid- and far-infrared (IR) wavelengths and offer powerful spectroscopic instruments and sensitivity three orders of magnitude better than that of the Herschel Space Observatory, the largest telescope flown in space to date. We describe the baseline concept for Origins recommended to the 2020 US Decadal Survey in Astronomy and Astrophysics. The baseline design includes a 5.9-m diameter telescope cryocooled to 4.5 K and equipped with three scientific instruments. A mid-infrared instrument (Mid-Infrared Spectrometer and Camera Transit spectrometer) will measure the spectra of transiting exoplanets in the 2.8 to 20 μm wavelength range and offer unprecedented spectrophotometric precision, enabling definitive exoplanet biosignature detections. The far-IR imager polarimeter will be able to survey thousands of square degrees with broadband imaging at 50 and 250 μm. The Origins Survey Spectrometer will cover wavelengths from 25 to 588 μm, making wide-area and deep spectroscopic surveys with spectral resolving power R ∼ 300, and pointed observations at R ∼ 40;000 and 300,000 with selectable instrument modes. Origins was designed to minimize complexity. The architecture is similar to that of the Spitzer Space Telescope and requires very few deployments after launch, while the cryothermal system design leverages James Webb Space Telescope technology and experience. A combination of current-state-of-the-art cryocoolers and next-generation detector technology will enable Origins’ natural background-limited sensitivity.

David Leisawitz↗

NASA NTRSDate not supplied

Design and Predicted Performance of 4-m Baseline Habitable-Zone Exoplanet Observatory Telescope

The Habitable Exoplanet Observatory Mission (HabEx) is one of four missions which NASA is studying. Its goal is to directly image and spectroscopically characterize planets in the habitable zone around nearby sun-like stars. Additionally, HabEx would perform a broad range of general astrophysics science enabled by 115 to 1700 nm spectral range and 3x3 arc-minute FOV instruments. Critical to achieving its science goals is a large, ultra-stable UV/Optical/Near-IR (UVOIR) telescope. The baseline HabEx telescope is a 4-meter off-axis unobscured three-mirror-anastigmatic, diffraction limited at 400 nm with wavefront stability on the order of a few 10s of picometers. This paper summarizes how science driven systems engineering (using science requirements to derive engineering specifications) resulting in the opto-mechanical design of the HabEx baseline optical telescope assembly. And, how Structural Thermal Optical Performance (STOP) modeling predicts tolerance compliance.

H Philip Stahl↗

NASA NTRSDate not supplied

Normative Baseline Oculomotor Performance

Future missions to the moon or Mars will require the crew to monitor and assess their health and performance more autonomously, necessitating approaches that are easily useable and interpretable by non-clinicians. The eye-movement-based performance metrics (oculometrics) obtained from NASA-patented technology developed at the Visuomotor Control Laboratory can reliably detect and discriminate the source of mild neural impairment relative to an individual’s baseline visual and sensorimotor performance and can predict performance in manual control tasks. This study aims to develop a database of normative performance that can be used to enable the detection of impairment without a within-subject baseline and to facilitate power analyses for the design of future studies.

eye movements↗

NASA NTRSDate not supplied

Analysis and Optimization of Baseline Single Aisle Aircraft for Future Electrified Powertrain Flight Demonstrator Comparisons

The purpose of this study is to provide baseline single-aisle vehicles for future comparisons NASA’s Electrified Powertrain Flight Demonstrator (EPFD) turbofan powered Vision Systems. Both a large single-aisle (≈150 passenger) and a small single-aisle (≈100 passenger) vehicle will be analyzed using NASA’s General Aviation Synthesis Program and a modernized Python-based version of this program that enables efficient gradient-based optimization of both the airframe and propulsion that currently is being referred to as GASPy. A technology build-up will be conducted to bring the current State-of-the-art vehicles to a projected 2035 technology level by incorporating estimations for improvements in aerodynamics, structures, and propulsions. These vehicles can be used in NASA’s future EPFD project as baselines to measure the benefits of future hybrid and fully electric aircraft against. The advanced, large single-aisle will then be used to demonstrate the benefits of a coupled engine-airframe optimization for fuel burn reduction.

Carl J Recine↗

NASA NTRS2006

Use of Very Long Baseline Array Interferometric Data for Spacecraft Navigation

The main VLBI technique that is used at JPL is known as the Delta Differential One-way Ranging ((Delta)DOR). Two DSN antennas simultaneously track a source, and alternate between sources. The signals recorded at the antennas from each source are correlated to obtain the delay in arrival to the two antennas, and the delays are differenced to remove common-source errors. An alternative technique is to use carrier phase differences between antennas. This is routinely done by the Very Large Baseline Array (VLBA) as part of source imaging. The VLBA capabilities are used for scientific research, but also have the potential to be used for navigation. Two main experiments were performed with the VLBA and JPL spacecraft. This paper describes and analyzes these experiments and discusses the possible uses of VLBA tracking for spacecraft navigation.

Very Large Baseline Array (VLBA)↗

NASA NTRS1996

Theoretical Modeling in Very Long Baseline Interferometry

Interferometry at radio frequencies between Earth-based receivers separated by intercontinental distances had made significant contributins to astrometry and geophysics during the past three decades, Analyses of such very long baseline interferometric (VLBI) experiments now permit measurements of relative positions of points on the Earth's surface, and angles between celestial objects, at the levels of 1cm and 1 nanoradian, respectively. The relative angular positions of extragalactic radio sources inferred from this technique presently form the best ralization of an inertial reference frame. This review summarizes the current theoretical models that are needed to extract results from the VLBI observables at such levels of accuracy.

interferometric VLBI extragalactic radio sources↗