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At least 541 records · Page 30

User's guide to the UTIL-ODRC tape processing program

The UTIL-ODRC computer compatible tape processing program, its input/output requirements, and its interface with the EXEC 8 operating system are described. It is a multipurpose orbital data reduction center (ODRC) tape processing program enabling the user to create either exact duplicate tapes and/or tapes in SINDA/HISTRY format. Input data elements for PRAMPT/FLOPLT and/or BATCH PLOT programs, a temperature summary, and a printed summary can also be produced.

Juba, S. M.↗

Technology Readiness Assessment Best Practices Guide

This guide establishes standard definitions and best practices for conducting technology readiness assessments (TRAs) for in flight projects and NASA’s research and technology missions. These best practices originated from a NASA TRA Committee that met weekly in 2014. The team was co-led by the Headquarters (HQ) Office of the Chief Engineer (OCE) and the HQ Office of the Chief Technologist (OCT), and included one to two representatives from each Center.

Technology readiness level↗

Design and Use of a Guided Weight Impactor to Impart Barely Visible Impact Damage

Aircraft structure is required to demonstrate satisfaction of the FAR requirements for Category 1, such as barely visible impact damage (BVID). Typical aircraft structure is impacted using a dropped weight impactor, which can impart BVID to the top surface of the structure. A recent test of a multi-bay box (MBB) composite test article, that represents an 80% scale center section of a hybrid wing body aircraft, required impact to be in a direction other than vertical from above, but still in an direction that is normal to the surface. This requirement eliminated the use of the conventional dropped weight impactor. Therefore, a design study was undertaken to determine the most effective way to efficiently and reliably impact the MBB. The chosen design was a guided weight impactor that is gravity driven. This paper describes the design of the guided weight impactor, and presents the results of its use for imparting BVID to the MBB. The guided weight impactor was seen to be a very reliable method to impart BVID, while at the same time having the capability to be highly configurable for use on other aircraft structure that is impacted at a variety of impact energies and from a variety of directions.

Lovejoy, Andrew E.↗

Modulating metal-centered dimerization of a lanthanide chaperone protein for separation of light lanthanides

Elucidating details of biology’s selective uptake and trafficking of rare earth elements, particularly the lanthanides, has the potential to inspire sustainable biomolecular separations of these essential metals for myriad modern technologies. Here, we biochemically and structurally characterize Methylobacterium (Methylorubrum) extorquens LanD, a periplasmic protein from a bacterial gene cluster for lanthanide uptake. This protein provides only four ligands at its surface-exposed lanthanide-binding site, allowing for metal-centered protein dimerization that favors the largest lanthanide, La III . However, the monomer prefers Nd III and Sm III , which are disfavored lanthanides for cellular utilization. Structure-guided mutagenesis of a metal-ligand and an outer-sphere residue weakens metal binding to the LanD monomer and enhances dimerization for Pr III and Nd III by 100-fold. Selective dimerization enriches high-value Pr III and Nd III relative to low-value La III and Ce III in an all-aqueous process, achieving higher separation factors than lanmodulins and comparable or better separation factors than common industrial extractants. Finally, we show that LanD interacts with lanmodulin (LanM), a previously characterized periplasmic protein that shares LanD’s preference for Nd III and Sm III . Our results suggest that LanD’s unusual metal-binding site transfers less-desirable lanthanides to LanM to siphon them away from the pathway for cytosolic import. The properties of LanD show how relatively weak chelators can achieve high selectivity, and they form the basis for the design of protein dimers for separation of adjacent lanthanide pairs and other metal ions.

lanthanide biochemistry↗

Information-Guided Dynamic Nuclear Polarization

A spin ensemble in thermal equilibrium continuously undergoes random fluctuations analogous to those observed in Brownian motion, a process known as spin noise. Here, we investigate the dynamics of a system comprising a spin-1 paramagnetic center and a hyperfine-coupled spin-1/2 nucleus in the vicinity of a level crossing. We theoretically show that nuclear spins polarize efficiently under the combined action of thermal fluctuations and a closed-loop feedback protocol. The latter articulates periodic observations of the electronic magnetization and radio-frequency pulses connecting hybrid states with opposite nuclear spin alignment. Since nuclear polarization emerges from electronic spin fluctuations, not spin order, this microwave-free technique generically benefits from warmer, not colder, operation temperatures. Furthermore, because the spin dynamics at play near a level crossing is rather insensitive to the absolute value of the magnetic field, our work promises opportunities for high-field dynamic nuclear polarization, which is difficult to attain through present methods.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗

A method for calculating a real-gas two-dimensional nozzle contour including the effects of gamma

A method for calculating two-dimensional inviscid nozzle contours for a real gas or an ideal gas by the method of characteristics is described. The method consists of a modification of an existing nozzle computer program. The ideal-gas nozzle contour can be calculated for any constant value of gamma. Two methods of calculating the center-line boundary values of the Mach number in the throat region are also presented. The use of these three methods of calculating the center-line Mach number distribution in the throat region can change the distance from the throat to the inflection point by a factor of 2.5. A user's guide is presented for input to the computer program for both the two-dimensional and axisymmetric nozzle contours.

Johnson, C. B.↗

Toys in Space, 2

In this educational video from the 'Liftoff to Learning' series, astronauts from the STS-54 Mission (Mario Runco, John Casper, Don McMonagle, Susan Helms, and Greg Harbaugh) explain how microgravity and weightlessness in space affects motion by using both mechanical and nonmechanical toys (gravitrons, slinkys, dart boards, magnetic marbles, and others). The gravitational effects on rotation, force, acceleration, magnetism, magnetic fields, center of axis, and velocity are actively demonstrated using these toys through experiments onboard the STS-54 Mission flight as a part of their spaceborne experiment payload. [Resource Guide referenced in the video is not available.]

Herbert, Dexter↗

Seeding for laser velocimetry in confined supersonic flows with shocks

There is a lack of firm conclusions or recommendations in the open literature to guide laser velocimeter (LV) users in minimizing the uncertainty of LV data acquired in confined supersonic flows with steep velocity gradients. This fact led the NASA Lewis Research Center (LeRC) in Cleveland (Ohio, USA), and the Institute of Propulsion Technology of DLR in Cologne (Germany) to a joint research effort to improve reliability of LV measurements in supersonic flows. Over the years, NASA and DLR have developed different expertise in laser velocimetry, using different LV systems: Doppler and two-spot (L2F). The goal of the joint program is to improve the reliability of LV measurements by comparing results from experiments in confined supersonic flows performed under identical test conditions but using two different LV systems and several seed particle generators. Initial experiments conducted at the NASA LERC are reported in this paper. The experiments were performed in a narrow channel with Mach number 2.5 flow containing an oblique shock wave generated by an immersed 25-dg wedge.

Lepicovsky, J.↗

Next Generation User Support Tools

One of the manually intensive efforts of Hubble Space Telescope (HST) observing is the specification and validation of the detailed proposals for scientists observing with the telescope. In order to meet the operational cost objectives for the Next Generation Space Telescope (NGST), this process needs to be dramatically less time consuming and less costly. We have prototyped a new proposal development system, the Scientist's Expert Assistant (SEA), using a combination of artificial intelligence and user interface techniques to reduce the time and effort involved for both scientists and the telescope operations staff. The Advanced Architectures and Automation Branch of NASA's Goddard Space Flight Center is working with the Space Telescope Science Institute (ST ScI) to explore SEA alternatives. We are testing the usefulness of rule-based expert systems to painlessly guide a scientist to his or her desired observation specification. We are also examining several potential user interface paradigms and exploring data visualization schemes to see which techniques are more intuitive. Our prototypes will be validated using HST's Advanced Camera for Surveys (ACS) instrument (scheduled for installation in 1999) as a live test instrument. Having an operational test-bed will ensure the most realistic feedback possible for the prototyping cycle. In addition, once the NGST instruments are better defined, the SEA will already be a proven platform that simply needs adapting to NGST-specific instruments.

Jones, Jeremy E.↗

Space Science Reference Guide, 2nd Edition

This Edition contains the following reports: GRACE: Gravity Recovery and Climate Experiment; Impact Craters in the Solar System; 1997 Apparition of Comet Hale-Bopp Historical Comet Observations; Baby Stars in Orion Solve Solar System Mystery; The Center of the Galaxy; The First Rock in the Solar System; Fun Times with Cosmic Rays; The Gamma-Ray Burst Next Door; The Genesis Mission: An Overview; The Genesis Solar Wind Sample Return Mission; How to Build a Supermassive Black Hole; Journey to the Center of a Neutron Star; Kepler's Laws of Planetary Motion; The Kuiper Belt and Oort Cloud ; Mapping the Baby Universe; More Hidden Black Hole Dangers; A Polarized Universe; Presolar Grains of Star Dust: Astronomy Studied with Microscopes; Ring Around the Black Hole; Searching Antarctic Ice for Meteorites; The Sun; Astrobiology: The Search for Life in the Universe; Europa and Titan: Oceans in the Outer Solar System?; Rules for Identifying Ancient Life; Inspire ; Remote Sensing; What is the Electromagnetic Spectrum? What is Infrared? How was the Infrared Discovered?; Brief History of Gyroscopes ; Genesis Discovery Mission: Science Canister Processing at JSC; Genesis Solar-Wind Sample Return Mission: The Materials ; ICESat: Ice, Cloud, and Land Elevation Satellite ICESat: Ice, Cloud, and Land; Elevation Satellite ICESat: Ice, Cloud, and Land Elevation Satellite ICESat: Ice, Cloud, and Land Elevation Satellite ICESat: Ice, Cloud, and Land Elevation Satellite Measuring Temperature Reading; The Optical Telescope ; Space Instruments General Considerations; Damage by Impact: The Case at Meteor Crater, Arizona; Mercury Unveiled; New Data, New Ideas, and Lively Debate about Mercury; Origin of the Earth and Moon; Space Weather: The Invisible Foe; Uranus, Neptune, and the Mountains of the Moon; Dirty Ice on Mars; For a Cup of Water on Mars; Life on Mars?; The Martian Interior; Meteorites from Mars, Rocks from Canada; Organic Compounds in Martian Meteorites May be Terrestrial Contaminants; Bands on Europa;Big Mountain, Big Landslide on Jupiter's Moon, Io; Cratering of the Moon; Europa's Salty Surface; The Europa Scene in the Voyager-Galileo Era; Explosive Volcanic Eruptions on the Moon; Ice on the Bone Dry Moon; Jupiter's Hot, Mushy Moon; The Moon Beyond 2002 ; Phases of the Moon; The Ph-D Project: Manned Expedition to the Moons of Mars; and Possible Life in a Europan Ocean.

Dotson, Renee↗

Dynamic Stability Testing of the Mars Science Laboratory Entry Capsule

Results from a 26 shot ballistic range test of the Mars Science Laboratory (MSL) entry capsule are presented. The supersonic pitch damping properties of the MSL capsule were characterized between Mach 1.35 and Mach 3.5 and total angles-of-attack from 0 to 30 degrees. In flight, the MSL entry capsule will utilize a radial center-of-gravity offset to produce a non-zero trim angle-of-attack. This offset trim angle will produce lift, enabling the capsule to fly a guided entry and reducing the landing footprint dimensions to within 10 km of the desired landing site. A lifting configuration could not be tested at the ballistic range used for this test as the models would swerve into the range walls, possibly damaging cameras, the coordinate reference system or other facility assets. Ballistic (non-lifting) data was extracted and will be implemented in a conservative fashion to ensure that the dynamic stability characteristics of the flight vehicle are bounded. A comparison between the MSL pitch damping results and the dynamic model of the Mars Exploration Rover capsule shows generally close agreement with no significant differences in damping characteristics due to the change in backshell geometry. Dynamic moments are also compared to the MSL reaction control system (RCS) control authority to show the controller has sufficient margin to easily damp any dynamic stability effects.

Schroenenberger, Mark↗

EP/TOMS Science Data Processing Programmer's Guide. Version 1.9

This EP/TOMS Programmer's Guide provides detailed information concerning the data, software, operations, and maintenance of the EP/TOMS Science Data Processing System. This system was developed for the NASA Goddard Space Flight Center (GSFC), Laboratory for Atmospheres, Atmospheric Chemistry Branch (Code 916) by SSAI. The description of the EP/TOMS Science Data Processing System starts with an overall system perspective (Section 3). A description of all data files ingested, stored, and/or produced follows in Section 4. Detailed descriptions of each major software subsystem are in Section 5. Section 6 presents processing procedures. Section 7 presents maintenance procedures. Procedures for updating this document are included in Section 7.

Source record↗

Lightweight Thrust Chamber Composite Overwrap Lessons Learned

The manufacturing, design, and analysis of filament wound carbon fiber/polymer composite overwraps for additively manufactured, copper combustion chambers are a critical part of NASA’s Rapid Analysis and Manufacturing Propulsion Technology (RAMPT) project. Ideally, the composite overwrap acts as a light-weight structural jacket and allows significant weight reduction of the high pressure thrust chamber assembly, reduction of overall cost, and reduced fabrication schedules. Chamber assemblies for 2000 lb. (2k) and 7000 lb. (7k) of thrust have been successfully tested at NASA’s Marshall Space Flight Center. Multiple lessons were learned throughout the overwrap process development and manufacturing trials. The lessons learned on small scale hardware, such as the 2k and 7k chambers, will guide further composite manufacturing technologies and enable a progression to larger scale assemblies with greater structural loads. Material performance requirements, manufacturing process development, and surface preparation were evaluated during the small chamber trials, with the broad thermal requirements of the resin being the primary driver for material selection and processing. Both epoxy and bismaleimide (BMI) materials were evaluated with respect to both performance in the hot-fire test and ease of fabrication. Separately, surface preparation procedures were studied with the goal of providing a smooth chamber surface to promote a non-bonded overwrap. Recent testing of the 7k trust chamber has provided data in Non-Destructive Evaluation (NDE) and processing in order to continue to evaluate the performance requirements stated.

Allison Clark↗

Phase Transitions of Eutectic High Entropy Alloy AlCoCrFeNi 2.1 Under Shock Compression

High entropy alloys (HEAs) are a new class of metals that exhibit unique mechanical performance. Among HEAs, additively manufactured eutectic high entropy alloys (AM EHEAs) have recently emerged as candidate materials for use in extreme conditions due to their simultaneous high strength and ductility. However, the deformation and structural evolution of AM EHEAs under conditions of high pressure have not been well characterized, limiting their use in extreme applications. Dynamic compression experiments and molecular dynamics simulations are presented to study the structural evolution of AM EHEA AlCoCrFeNi 2.1 when compressed to pressures up to 400 GPa. In situ X-ray diffraction measurements capture the appearance of face-centered cubic and body-centered cubic phases at different pressure conditions, with pure- and mixed-phase regions. Furthermore, understanding the phase stability and structural evolution of the AM EHEA offers new insights to guide the development of high-performance complex materials for extreme conditions.

36 MATERIALS SCIENCE↗

Status of Regenerative Life Support Research and Technology Program at NASA Ames Research Center

1. Provide Advanced Life Support technologies that significantly reduce life cycle costs, improve operational performance, promote self-sufficiency, and minimize expenditure of resources for missions of long duration. 2. Develop and apply methods of systems analysis and engineering to guide investments in technology, resolve and integrate competing needs, and guide evolution of advanced life support systems. 3. Resolve issues of hypogravity performance through space flight research and evaluation. 4. Ensure timely transfer of new life support technologies to missions. 5. Transfer technologies to private sectors for national benefit.

Kliss, Mark↗

Developing Scenario‐Based Strategies for Health, Climate, and Environmental Preparedness: The One Health, One Earth Approach

Climate change amplifies many threats to human health. Despite advances in understanding climate change dynamics and impacts, there remains a critical gap in translating scientific knowledge into equitable, and community-driven health interventions. The inaugural One Earth, One Health workshop sought to explore this gap through human-centered design exercises involving interdisciplinary researchers from climate and Earth sciences, engineering, epidemiology, microbiology, and environmental health. Although participants did not co-develop solutions with affected communities, they used stakeholder role-playing to guide ideation and lay groundwork for actionable plans. Through these methods, participants identified community needs and proposed prototype solutions to alleviate health threats exacerbated by global environmental change. Prototypes were organized around infectious diseases, extreme weather, and air quality, as illustrative themes rather than an exhaustive set of risks. Key solutions included strategies for anticipatory systems and early warning (e.g., integrating environmental signals with health data), inclusive communication and infrastructure needs for responding to extreme weather events, and integrated platforms visualizing air quality trends to support tailored, context-aware guidance beyond one-size-fits-all alerts. The workshop highlighted opportunities such as leveraging machine learning, Earth observation, and real-time surveillance to protect communities, but also noted barriers including data quality, technological redundancy, privacy, and governance challenges. Additionally, participants emphasized the need for interdisciplinary teams capable of collaborating across sectors, breaking down silos and addressing gaps in training and education. Overall, the workshop illustrates how process-driven, human-centered approaches can help surface user needs and generate testable prototype concepts, while underscoring the importance of direct community partnership for implementation.

Abadi, Azar M. [University of Alabama, Birmingham,↗

Guaranteeing Pointing Performance of the SDO Sun-Pointing Controllers in Light of Nonlinear Effects

The Solar Dynamics Observatory (SDO) mission is the first Space Weather Research Network mission, part of NASA s Living With a Star program.1 This program seeks to understand the changing Sun and its effects on the Solar System, life, and society. To this end, the SDO spacecraft will carry three Sun-observing instruments to geosynchronous orbit: Helioseismic and Magnetic Imager (HMI), led by Stanford University; Atmospheric Imaging Assembly (AIA), led by Lockheed Martin Space and Astrophysics Laboratory; and Extreme Ultraviolet Variability Experiment (EVE), led by the University of Colorado. Links describing the instruments in detail may be found through the SDO web site.2 The basic mission goals are to observe the Sun for a very high percentage of the 5-year mission (10-year goal) with long stretches of uninterrupted observations and with constant, high-data-rate transmission to a dedicated ground station. These goals guided the design of the spacecraft bus that will carry and service the three-instrument payload. At the time of this publication, the SDO spacecraft bus is well into the integration and testing phase at the NASA Goddard Space Flight Center (GSFC). A three-axis stabilized attitude control system (ACS) is needed both to point at the Sun accurately and to keep the roll about the Sun vector correctly positioned. The ACS has four reaction wheel modes and 2 thruster actuated modes. More details about the ACS in general and the control modes in particular can be found in Refs. [3-6]. All four of SDO s wheel-actuated control modes involve Sun-pointing controllers, as might be expected from such a mission. Science mode, during which most science data is collected, uses specialized guide telescopes to point accurately at the Sun. Inertial mode has two sub-modes, one tracks a Sun-referenced target orientation, and another maintains an absolute (star-referenced) target orientation, that both employ a Kalman filter to process data from a digital Sun sensor and two star trackers. However, this paper is concerned only with the other two modes: Safe Hold (SH) and Sun Acquisition (SA).

Starin, Scott R.↗

G3P3 Phase 3 Project Execution Plan. Issue 1

The National Solar Thermal Test Facility (NSTTF) at Sandia National Laboratories New Mexico (SNL/NM) developed this Project Execution Plan (PEP) to document its process for executing, monitoring, controlling and closing-out Phase 3 of the Gen 3 Particle Pilot Plant G3P3. This plan serves as a resource for stakeholders who wish to be knowledgeable of project objectives and how they will be accomplished. The plan is intended to be used by the development partners, principal investigator, and the federal project director. Project objectives are derived from the mission needs statement, and an integrated project team assists in development of the PEP. This plan is a living document and will be updated throughout the project to describe current and future processes and procedures. The scope of the PEP covers: Cost, schedule, and scope Project reporting Staffing plan Quality assurance plan Environment, safety, security, and health This document is a tailored approach for the Facilities Management and Operations Center (FMOC) to meet the project management principles of DOE Order 413.3B, Program and Project Management for the Acquisition of Capital Assets , and DOE G 413.3-15, DOE Guide for Project Execution Plans. This document will elaborate on content as knowledge of the project is gained or refined.

14 SOLAR ENERGY↗