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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 19 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS2005

Synthesis and Near IR Photoluminescence of Os(II) Bis(2,2'-bipyridine) (3,8-Diarylethynyl-1,10-phemanthroline) Complexes: Anomalous Behavior of the 3,8-Dinitrophenylethynyl-substituted Homologue

A large bathochromic shift (50 nm) and emission in the near infrared is observed by attaching arylethynyl groups at the 3,8-positions of the 1,10-phenanthroline ligand (phen) of [Os(bipy)2(phen)]2+ (where bipy = 2,2'-bipyridine). Thus [Os(bipy)2(3,8-di-4-methoxyphenylethynyl-1,10-phenathroline)]2+ emits at 795 nm, while [Os(bipy)2(3,8-diphenylethynyl-1,10-phenanthroline)]2+ emits at 815 nm. According to this trend it would have been expected that [Os(bipy)2(3,8-di-4-nitrophenylethynyl-1,10-phenathroline)]2+ emits farther in the near infrared. Nevertheless, this complex is not photoluminescent because of intramolecular electron transfer quenching of the MLCT excited state by the nitroaromatic group. These results set structural and redox potential standards in the design of near infrared emitters based on [Os(bipy)2(phen)]2+ type complexes.

Yang, Jinhua↗
NASA NTRS1973

NASIS data base management system - IBM 360/370 OS MVT implementation. 2: Overviews

The systems overviews of the NASA Aerospace Safety Information System (NASIS) are presented. The overviews are directed toward informing management of a system's capabilities and requirements. The intent of the overviews is to introduce the system features to interested individuals. Each overview contains a description of the component's activities and roles in the overall system. The description includes charts and diagrams and a discussion of the performance requirements and growth potential of the module.

Source record↗
NASA NTRS1990

Ultraviolet light curves of galactic and extra-galactic classical CNO novae: PW Vul, OS, and LMC 1988 no. 1 and no. 2

In order to determine the comparative energy budgets of novae in outburst, the ultraviolet light curves for a number of novae are determined. The low dispersion IUE (International Ultraviolet Explorer) spectra of PW Vul 1984, OS And 1986, LMC 1988 number 1 and number 2 and obtained values for the integrated energy emitted in the wavelength interval from 1200 to 3400 A, not including the geocoronal Lyman-alpha emission line are re-examined. The light curves show that the brightness of the nova declines much more slowly in the ultraviolet than the optical, that the maximum brightness of the nova occurs much later in the ultraviolet than in the optical, and the peak luminosity is super Eddington for LMC 1988 number 2.

Austin, S.↗
NASA NTRS2007

Os-186 and Os-187 Enrichments and High-He-3/He-4 sources in the Earth's Mantle: Evidence from Icelandic Picrites

Picrites from the neovolcanic zones in Iceland display a range in Os-187/Os-188O from 0.1297 to 0.1381 ((gamma)Os = 0.0 to 6.5) and uniform Os-186/Os-188 of 0.1198375+/-32 (2 (sigma)). The value for Os-186/Os-188 is within uncertainty of the present-day value for the primitive upper mantle of 0.1198398+/-16. These Os isotope systematics are best explained by ancient recycled crust or melt enrichment in the mantle source region. If so, then the coupled enrichments displayed in Os-186/Os-188 and Os-187/Os-188 from lavas of other plume systems must result from an independent process, the most viable candidate at present remains core-mantle interaction. While some plumes with high He-3/He-4, such as Hawaii, appear to have been subjected to detectable addition of Os (and possibly He) from the outer core, others such as Iceland do not. A positive correlation between Os-187/Os-188 and He-3/He-4 from 9.6 to 19 RA in Iceland picrites is best modeled as mixtures of 500 Ma or older ancient recycled crust mixed with primitive mantle, creating a hybrid source region that subsequently mixes with the convecting MORB mantle during ascent and melting. This multistage mechanism to explain these isotope systematics is consistent with ancient recycled crust juxtaposed with more primitive, relatively He-rich mantle, in convective isolation from the upper mantle, most likely in the lowermost mantle. This is inconsistent with models that propose random mixing between heterogeneities in the convecting upper mantle as a mechanism to explain the observed isotopic variation in oceanic lavas or models that produce a high He-3/He-4 signature in melt depleted and strongly outgassed, He-poor mantle. Instead these systematics require a deep mantle source to explain the 3He/4He signature in Iceland lavas. The He-3/He-4 of lavas derived from the Iceland plume changed over time, from a maximum of 50 RA at 60 Ma, to approximately 25-27 RA at present. The changes are coupled with distinct compositional gaps between the different aged lavas when H-3/He-4 is plotted versus various geochemical parameters such as Nd-143/Nd-144 and La/Sm. These relationships can be interpreted as an increase in the proportion of ancient recycled crust in the upwelling plume over this time period.

Brandon, Alan D.↗
NASA NTRS2018

An Orbiting Sample Capture and Orientation System Architecture for Potential Mars Sample Return

An orbiting sample capture and orientation system architecture for a Rendezvous and Orbiting Sample Capture System (ROCS) concept was developed to enable spacecraft based, in-orbit capture, orientation, and transfer of a Mars sample container into a containment vessel as part of a potential Mars Sample Return (MSR) campaign. An analysis of the system functions, requirements, interactions, and constraints was performed. A trade study was carried out on relevant technologies, and a set of evaluation criteria was developed to help determine the most feasible concepts for implementation. The Mars Capture and Re-orientation for the potential Next Mars Orbiter (MACARONE) concept is proposed as a promising system architecture for the ROCS Capture and Orient Module (COM). The concept uses a sliding trap door for Orbiting Sample (OS) capture, a Motorized Cups Mechanism for OS orientation, and a 2 DOF Turret Arm with a paddle for transferring the OS into a containment vessel. This approach facilitates modularity, development flexibility, test-ability in a 1G environment, analyze-ability without the need to simulate or test for 0G contact dynamics, ability to encapsulate potential dust surrounding the OS, and ability to be ejected to reduce the probability of Earth exposure to non-sterilized Mars material.

Lalla, Karan↗
NASA NTRS2010

GN and C Design Overview and Flight Test Results from NASA's Max Launch Abort System (MLAS)

The National Aeronautics and Space Administration (NASA) Engineering and Safety Center (NESC) designed, developed and flew the alternative Max Launch Abort System (MLAS) as risk mitigation for the baseline Orion spacecraft launch abort system (LAS) already in development. The NESC was tasked with both formulating a conceptual objective system (OS) design of this alternative MLAS as well as demonstrating this concept with a simulated pad abort flight test. The goal was to obtain sufficient flight test data to assess performance, validate models/tools, and to reduce the design and development risks for a MLAS OS. Less than 2 years after Project start the MLAS simulated pad abort flight test was successfully conducted from Wallops Island on July 8, 2009. The entire flight test duration was 88 seconds during which time multiple staging events were performed and nine separate critically timed parachute deployments occurred as scheduled. Overall, the as-flown flight performance was as predicted prior to launch. This paper provides an overview of the guidance navigation and control (GN&C) technical approaches employed on this rapid prototyping activity. This paper describes the methodology used to design the MLAS flight test vehicle (FTV). Lessons that were learned during this rapid prototyping project are also summarized.

Dennehy, Cornelius J.↗
NASA NTRS1992

Ultraviolet studies of Novae in the Large Magellanic Cloud

We report on the ultraviolet observations of five novae in the Large Magellanic Cloud (LMC). They are LMC 1988 #1, which was a CO nove similar to OS And; LMC 1988 #2, which was an ONeMg nova similar to Nova Her 1991; LNC 1990 #1, which was a very fast ONeMG nova similar to V693 CrA 1981; LMC 1990 #2, which was a recurrent nova similar to U Sco; and LMC 1991 which reached V approximately 9.

Starrfield, Sumner↗
NASA NTRS1973

SUMC/MPOS/HAL interface study

The implementation of the HAL/S language on the IBM-360, and in particular the mechanization of its real time, I/O, and error control statements within the OS-360 environment is described. The objectives are twofold: (1) An analysis and general description of HAL/S real time, I/O, and error control statements and the structure required to mechanize these statements. The emphasis is on describing the logical functions performed upon execution of each HAL statement rather than defining whether it is accomplished by the compiler or operating system. (2) An identification of the OS-360 facilities required during execution of HAL/S code as implemented for the current HAL/S-360 compiler; and an evaluation of the aspects involved with interfacing HAL/S with the SUMC operating system utilizing either the HAL/S-360 compiler or by designing a new HAL/S-SUMC compiler.

Saponaro, J. A.↗
NASA NTRS2022

The Scientific Importance of Returning Airfall Dust as a Part of Mars Sample Return (MSR)

Dust transported in the martian atmosphere is of intrinsic scientific interest and has relevance for the planning of human missions in the future. The MSR Campaign, as currently designed, presents an important opportunity to return serendipitous, airfall dust. The tubes containing samples collected by the Perseverance rover would be placed in cache depots on the martian surface perhaps as early as 2023–24 for recovery by a subsequent mission no earlier than 2028–29, and possibly as late as 2030–31. Thus, the sample tube surfaces could passively collect dust for multiple years. This dust is deemed to be exceptionally valuable as it would inform our knowledge and understanding of Mars' global mineralogy, surface processes, surface-atmosphere interactions, and atmospheric circulation. Preliminary calculations suggest that the total mass of such dust on a full set of tubes could be as much as 100 mg and, therefore, sufficient for many types of laboratory analyses. Two planning steps would optimize our ability to take advantage of this opportunity: (1) the dust-covered sample tubes should be loaded into the Orbiting Sample container (OS) with minimal cleaning and (2) the capability to recover this dust early in the workflow within an MSR Sample Receiving Facility (SRF) would need to be established. A further opportunity to advance dust/atmospheric science using MSR, depending upon the design of the MSR Campaign elements, may lie with direct sampling and the return of airborne dust.

Monica M. Grady↗
NASA NTRS2007

High-Precision Nd Isotopes in Picrites from Hawaii and Iceland - No Evidence for an Early-Formed Enriched Reservoir

New high-precision Nd isotope measurements have shown that the present-day Nd-142/Nd-144 for average chondrites is approximately 20 ppm lower than that for the terrestrial standard and all recent mantle-derived samples measured to date. One explanation for these differences is that an enriched missing reservoir with lower Nd-142/Nd-144 resides in the mantle to balance the bulk Earth to chondritic. Data from Archean Greenland rocks show anomalies in Nd-142/Nd-144 of up to 40 ppm higher than the proposed average for chondrites. This difference between the Archean Greenland rocks and present-day mantle-derived samples has been interpreted to result from remixing of an early-formed enriched reservoir into the convecting mantle during the Archean. If so, the implication from this is that remixing of the enriched reservoir largely shut down some time in the past such that it must at present reside in a region in the mantle that infrequently participates dynamically and leading to volcanism at the surface. Several studies have suggested that the missing reservoir may be present just above the coremantle boundary (CMB). Depending on the size of this reservoir it could potentially make up all of D or exist as distinct domains within it. If such a reservoir does exist, then mantle-derived samples from plume systems that are thought to come from the CMB may be the best opportunity to identify this component using high-precision Nd isotope measurements. To test this, picrites from Hawaii with coupled enrichments in Os-186-Os-187 that has been proposed to be a signature of core-mantle interaction were measured on the JSC Triton for high-precision Nd-142/Nd-144. For comparison, picrites from Hawaii and Iceland that do not show coupled enrichments in Os-186-Os-187 were measured. We have established an external precision for Nd-142/Nd-144 of 3.6 ppm (2 sigma) during the analytical campaign. The Iceland (n=5) and Hawaiian data (n=9) have Nd-142 ranging from -0.01 plus or minus 0.03 to +0.03 plus or minus 0.03 (2 sigma) and there is no resolvable difference between samples with Os isotope enrichments versus those without. The average epsilon Nd-142 of +0.011 plus or minus 0.034 (2 sigma ) for all of the samples (n=14) is not resolvable from the Ames and La Jolla standards with epsilon Nd-142 of +0.000 plus or minus 0.036 (n=16, 2 sigma). These data confirm recent measurements on lavas for the absence of an ancient enriched Nd-142 isotopic signature in plume systems likely derived from D and indicates that such a reservoir, if existing, must now reside in areas of the deep mantle that plumes do not sample.

Brandon, A. D.↗
NASA NTRS2003

Oscillatory shear stress stimulates endothelial production of O2- from p47phox-dependent NAD(P)H oxidases, leading to monocyte adhesion

Arterial regions exposed to oscillatory shear (OS) in branched arteries are lesion-prone sites of atherosclerosis, whereas those of laminar shear (LS) are relatively well protected. Here, we examined the hypothesis that OS and LS differentially regulate production of O2- from the endothelial NAD(P)H oxidase, which, in turn, is responsible for their opposite effects on a critical atherogenic event, monocyte adhesion. We used aortic endothelial cells obtained from C57BL/6 (MAE-C57) and p47phox-/- (MAE-p47-/-) mice, which lack a component of NAD(P)H oxidase. O2- production was determined by dihydroethidium staining and an electron spin resonance using an electron spin trap methoxycarbonyl-2,2,5,5-tetramethyl-pyrrolidine. Chronic exposure (18 h) to an arterial level of OS (+/- 5 dynes/cm2) increased O2- (2-fold) and monocyte adhesion (3-fold) in MAE-C57 cells, whereas chronic LS (15 dynes/cm2, 18 h) significantly decreased both monocyte adhesion and O2- compared with static conditions. In contrast, neither LS nor OS were able to induce O2- production and monocyte adhesion to MAE-p47-/-. Treating MAE-C57 with a cell-permeable superoxide dismutase compound, polyethylene glycol-superoxide dismutase, also inhibited OS-induced monocyte adhesion. In addition, over-expressing p47phox in MAE-p47-/- restored OS-induced O2- production and monocyte adhesion. These results suggest that chronic exposure of endothelial cells to OS stimulates O2- and/or its derivatives produced from p47phox-dependent NAD(P)H oxidase, which, in turn, leads to monocyte adhesion, an early and critical atherogenic event.

NASA Program Fundamental Space Biology↗
NASA NTRS2002

CIP Training Manual: Collaborative Information Portal Advance Training Information for Field Test Participants

The Collaborative Information Portal (CIP) is a web-based information management and retrieval system. Its purpose is to provide users at MER (Mars Exploration Rover) mission operations with easy access to a broad range of mission data and products and contextual information such as the current operations schedule. The CIP web-server provides this content in a user customizable web-portal environment. Since CIP is still under development, only a subset of the full feature set will be available for the EDO field test. The CIP web-portal will be accessed through a standard web browser. CIP is intended to be intuitive and simple to use, however, at the training session, users will receive a one to two page reference guide, which should aid them in using CIP. Users must provide their own computers for accessing CIP during the field test. These computers should be configured with Java 1.3 and a Java 2 enabled browser. Macintosh computers should be running OS 10.1.3 or later. Classic Mac OS (OS 9) is not supported. For more information please read section 7.3 in the FIASCO Rover Science Operations Test Mission Plan. Several screen shots of the Beta Release of CIP are shown on the following pages.

Schreiner, John↗
NASA NTRS1991

Frequency stability of GPS NAVSTAR block 1 and block 2 on-orbit clocks

Analysis of the frequency stability of the on-orbit NAVSTAR clocks os performed by the Naval Research Laboratory. The frequency stability is presented for sample times of one day to 30 days. Composite frequency stability profiles are presented for Block 1 and Block 2 NAVSTAR clocks. Several NAVSTAR cesium clocks show frequency stabilities of a few parts in 10^(14) for long sample times. Time-domain noise-process analysis shows the dominant noise type to be white frequency noise for sample times of one to ten days. The non-stationary stochastic behavior of one of the cesium clocks, illustrated by its frequency stability history, shows that the frequency stability is not always time-invariant.

Thomas B. Mccaskill↗
NASA NTRS1995

Geologic Map of the MTM-85000 Quadrangle, Mars

the geologic map presented here covers the portion of Mars between latitudes 82.5oS to 87.5oS, longitudes -20oW to 20oW. The Viking Orbiter 2 images used to construct the photomosaic base used for mapping were taken during the southern summer of 1977, with resolutions no better than 140 meters/pixel. A digital mosaic of Mariner 9 images was also constructed to aid in mapping. The Mariner 9 images were taken during the southern summer of 1971-72, and have resolutions as high as 85 meters/pixel. However, usefulness of the Mariner 9 mosaic is limited by incomplete coverage and atmospheric dust opacity.

MTM-85000 Mars↗
NASA NTRS2018

A Study of Various Beacon Antennas for an Orbiting Sample Container of a Future Mars Sample Return Mission

This paper presents some results of a study of various options for a near-omnidirectional low-gain antenna at UHF frequencies, for a Mars Orbiting Sample Return Container (OS). The OS is part of a concept study for a future mission to return samples from Mars. It would be a critical component of such a mission, which would contain the Mars samples. The notional OS would be returned by a separate spacecraft to Earth. The OS would be identified and located by the spacecraft for pick-up from orbit by a beacon signal broadcast via a surface antenna. Several antenna designs were considered, but two promising ones are presented here which have good patterns with a better than 2:1 VSWR (Voltage Standing Wave Ratio), but meet different criteria for OS design options. One is a patch-type antenna and the other a slot-type antenna. Some data and test results of a fabricated breadboard antenna as well as discussions are provided.

Jamnejad, Vahraz↗
NASA NTRS1971

Optimization techniques for FORTRAN 4 (G and H) programs written for the IBM 360 under OS

A fairly complete list is reported of programming techniques which are available to the programmer for optimizing the execution time of production programs written in FORTRAN IV (G and H) for the IBM 360 under OS. After the program has been complied under FORTRAN H, OPT=2, then the process of actually changing code begins. The bulk of execution time of FORTRAN programs can almost always be attributed to a few loops, and primary consideration is given to these.

Dean, J. L.↗
NASA NTRS1991

The shock wave equation of state of brucite Mg(OH)2

New shock equation of state (EOS) data on magnesium hydroxide between 12 and 60 GPa is presented. It is found that the brucite EOS data between 12 and 97 GPa can be fit with a single linear U(s) - u(p) relationship: U(s) = 4.76(0.11) + 1.35(0.05)u(p). The third order Birch-Murnaghan equation parameters are K(os) = 51 + or - 4 GPa and K(os)prime = 5.0 + or - 0.4. The first partial release states measured for brucite Mg(OH)2 are reported. Calculated phase boundaries using the EOS data are found to be consistent with the experimental data and indicate that brucite is unlikely to be stable under lower mantle conditions. At high pressure, bulk sound velocities calculated for MgO and Mg(OH)2 are very similar, indicating that the presence of hydrous assemblages in the lower mantle may not produce anomalous bulk seismic velocities. A comparison of densities in brucite and other high-pressure phases under mantle conditions shows that the water content of the lower mantle is between 0 and 3 wt pct.

Duffy, Thomas S.↗