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NASA NTRS2018

The Diversity of Refractory Organic Material in Comets

Organic matter exists in comets (most notably in 81P/Wild 2 [Stardust], 67P/Churyomov- Gerasimenko (67P/C-G) [Rosetta], chondritic porous IDPS, and UCAMMs) and in primitive carbonaceous chondrites that likely retain some chemistry that reflects an origin in the prenatal cold molecular cloud (Alexander+2017). Heavy isotopic enrichments, 15N/14N and possibly D/H, signify preserved molecular cloud organics. In the cold outer disk, if grains are lofted above the disk mid-plane then organics likely experience significant UV processing (Ciesla+2012). In remote sensing of comet comae, organics in the dust are considered refractory or semirefractory. Semi-refractory organics have limited comae lifetimes and produce distributed sources of molecules (H2CO and CO). Rosetta's close passes of 67P/C-G's nucleus (10-15 km) reveals a distributed source of glycine, methyl amine and ethylamine (Altwegg+2016). Cometary samples and primitive meteorites have two types of organic matter: (1) acid-insoluble organic matter (IOM), which is a macromolecular polymer with a mixture of aromatic and aliphatic moieties, and (2) labile, soluble organics, which includes the amino acids, such as glycine (Stardust, Elsila+2009). Meteoritic IOM is robust, withstanding experimental temperatures of 1200 K (Dobrica+2011, Cody+2008). Nanoglobules are a type of IOM; they have a distinct physical structure, but often share the same chemistry as the other IOM from the same meteorite. Moderate-sized PAHs (20 C-atoms) are detected in Stardust samples (Clemett+2010). Refractory organic IOM is ubiquitous yet has a great diversity of abundances between cometary samples. IOM is in primitive chondrites, 67P/C-G (Rosetta), 81P/Wild 2 (Stardust), 1P/Halley, 26P/Grigg-Skjellerup, UCAMMs, anhydrous IDPs, and in chondritic porous IDPs (CP IDPs) and larger cluster IDPs (e.g., Fray+2016, Fomenkova+94, Busemann+ 09, Dobrica+2011, Dobrica+2012). 81P's refractory organic matter is of two types (De Gregorio+2011): nanoglobules of highly aromatic refractory organic matter and polyaromatic carbonyl-containing organic matter, which is similar to IOM in primitive meteorites and IDPs. Fray+2017 estimate that 50% of carbon in 67P/C-G is in IOM. 67P/C-G's organics appear to lack the soluble organic matter, aliphatic carbon, amino acids, and PAHs (Fray+2016). Other notable aspects of the diversity in IOM in cometary samples are the ranges of atomic ratios of N/C, O/C, and H/C, and the range of isotopic enrichments of 15N/14N and D/H. Aqueous and thermal processing on asteroids changes the balance of soluble to insoluble organics, and may be important for diversifying the range of OM delivered to Earth.

Wooden, Diane↗

NASA NTRS2011

Avionics Systems Laboratory/Building 16. Historical Documentation

As part of this nation-wide study, in September 2006, historical survey and evaluation of NASA-owned and managed facilities that was conducted by NASA s Lyndon B. Johnson Space Center (JSC) in Houston, Texas. The results of this study are presented in a report entitled, "Survey and Evaluation of NASA-owned Historic Facilities and Properties in the Context of the U.S. Space Shuttle Program, Lyndon B. Johnson Space Center, Houston, Texas," prepared in November 2007 by NASA JSC s contractor, Archaeological Consultants, Inc. As a result of this survey, the Avionics Systems Laboratory (Building 16) was determined eligible for listing in the NRHP, with concurrence by the Texas State Historic Preservation Officer (SHPO). The survey concluded that Building 5 is eligible for the NRHP under Criteria A and C in the context of the U.S. Space Shuttle program (1969-2010). Because it has achieved significance within the past 50 years, Criteria Consideration G applies. At the time of this documentation, Building 16 was still used to support the SSP as an engineering research facility, which is also sometimes used for astronaut training. This documentation package precedes any undertaking as defined by Section 106 of the NHPA, as amended, and implemented in 36 CFR Part 800, as NASA JSC has decided to proactively pursue efforts to mitigate the potential adverse affects of any future modifications to the facility. It includes a historical summary of the Space Shuttle program; the history of JSC in relation to the SSP; a narrative of the history of Building 16 and how it supported the SSP; and a physical description of the structure. In addition, photographs documenting the construction and historical use of Building 16 in support of the SSP, as well as photographs of the facility documenting the existing conditions, special technological features, and engineering details, are included. A contact sheet printed on archival paper, and an electronic copy of the work product on CD, are also provided

Slovinac, Patricia↗

NASA NTRS2013

Thermal Protection and Control

During all phases of a spacecraft's mission, a Thermal Protection System (TPS) is needed to protect the vehicle and structure from extreme temperatures and heating. When designing TPS, low weight and cost while ensuring the protection of the vehicle is highly desired. There are two main types of TPS, ablative and reusable. The Apollo missions needed ablators due to the high heat loads from lunar reentry. However, when the desire for a reusable space vehicle emerged, the resultant_ Space Shuttle program propelled a push for the development of reusable TPS. With the growth of reqsable TPS, the need for ablators declined, triggering a drop off of the ablator industry. As a result, the expertise was not heavily maintained within NASA or the industry. When the Orion Program initiated a few years back, a need. for an ablator reemerged. Yet, due to of the lack of industry capability, redeveloping the ablator material took several years and came at a high cost. As NASA looks towards the future with both the Orion and Commercial Crew Programs, a need to preserve reusable, ablative, and other TPS technologies is essential. Research of the different TPS materials alongside their properties, capabilities, and manufacturing process was performed, and the benefits of the materials were analyzed alongside the future of TPS. Knowledge of the different technologies has the ability to help us know what expertise to maintain and ensure a lack in the industry does not occur again.

Greene, Effie E.↗

NASA NTRSDate not supplied

A Gene Expression and Histologic Approach to Study Production and Outflow of Cerebrospinal Fluid in Hindlimb Suspended Rats

INTRODUCTION: The Spaceflight Associated Neuro-ocular Syndrome (SANS) is thought to be associated with weightlessness-induced cephalad fluid shift, possibly associated with a chronic elevation of intracranial pressure (ICP) during long-duration ISS missions. Changes in cerebrospinal fluid (CSF) dynamics and cranial compliance might be involved in the ICP increase. It is not known whether CSF production and/or outflow are altered in microgravity, but changes at the molecular and cellular level in the structures that produce and regulate the transcellular and paracellular secretion and reabsorption of CSF may be relevant. In this study, we used the rat hindlimb suspension (HS) model to examine the relationship between intracranial pressure (ICP) and the cellular responses to the prolonged change in body posture elicited specifically in the choroid plexus (CP). This was evaluated by transcriptomics, histopathology and ultrastructure of the CP and arachnoid villi (AV). METHODS: ICP was measured by telemetry. The morphology, ultrastructure, and gene expression profile of the CP was examined using male 9-month-old Long Evans rats subjected to HS for 14 and 90 days. A subset of animals completing 90-day HS returned to normal posture for 14 and 90 additional days of recovery. All HS rats had age-matched cage controls maintained in normal posture. A group of animals was maintained in conditions of 1% CO2 throughout the entire protocol. The rat brains were carefully removed and preserved for various analyses, including transmission electron microscopy (TEM), immunohistochemical analysis of specific targets involved in CSF regulation, and RNA sequencing analysis of laser capture micro-dissected CP tissue from the lateral ventricles. SUMMARY OF RESULTS: The ICP record was limited, which impacted any conclusions derived from the results. However, the ICP of rats in the CO2-enriched atmosphere appeared increased compared to those in a normal air composition. HS of rats resulted in an altered transcriptomics profile in the choroid plexus compared to animals maintained at normal posture. This was observed during both the HS period and during normal posture recovery period following 90 days of suspension. The greatest number of differentially expressed genes was observed at 90 days HS. Elevated CO2 also led to a different transcriptomics profile in the CP. The histology and ultrastructure results should be considered preliminary due to the limited number of samples. Examination of the CP by TEM showed blood vessel congestion and microvilli swelling in the CP, as well as some subpial and periventricular gliosis, but no associations were observed with treatment. There was no evidence of a reduced clearance of b-amyloid in the periventricular, perivascular and subpial regions of the brain in HS animals versus those in normal posture. Immunohistochemical staining of aquaporin 4, showed the localization to the subpial region and ependyma with increased immunoreactivity in the brains of CO2 exposed rats. This work was supported by awards NNX15AW48G to S.Z. Animal tissue and live data was provided under a tissue/data sharing agreement with Dr. Charles Fuller, UC Davis.

S B Zanello↗

NASA NTRSDate not supplied

A Gene Expression and Histologic Approach to Study Production and Outflow of Cerebrospinal Fluid in Hindlimb Suspended RATS

S B Zanello↗

NASA NTRS2009

Origins of Magnetite Nanocrystals in Martian Meteorite ALH84001

The Martian meteorite ALH84001 preserves evidence of interaction with aqueous fluids while on Mars in the form of microscopic carbonate disks. These carbonate disks are believed to have precipitated 3.9 Ga ago at beginning of the Noachian epoch on Mars during which both the oldest extant Martian surfaces were formed, and perhaps the earliest global oceans. Intimately associated within and throughout these carbonate disks are nanocrystal magnetites (Fe3O4) with unusual chemical and physical properties, whose origins have become the source of considerable debate. One group of hypotheses argues that these magnetites are the product of partial thermal decomposition of the host carbonate. Alternatively, the origins of mag- netite and carbonate may be unrelated; that is, from the perspective of the carbonate the magnetite is allochthonous. For example, the magnetites might have already been present in the aqueous fluids from which the carbonates were believed to have been deposited. We have sought to resolve between these hypotheses through the detailed characterized of the compo- sitional and structural relationships of the carbonate disks and associated magnetites with the orthopyroxene matrix in which they are embedded. Extensive use of focused ion beam milling techniques has been utilized for sample preparation. We then compared our observations with those from experimental thermal decomposition studies of sideritic carbonates under a range of plausible geological heating scenarios. We conclude that the vast majority of the nanocrystal magnetites present in the car- bonate disks could not have formed by any of the currently proposed thermal decomposition scenarios. Instead, we find there is considerable evidence in support of an alternative allochthonous origin for the magnetite unrelated to any shock or thermal processing of the carbonates.

Thomas-Keprta, Kathie L.↗

NASA NTRS2016

Overview of the NASA Glenn Flux Reconstruction Based High-Order Unstructured Grid Code

A computational fluid dynamics code based on the flux reconstruction (FR) method is currently being developed at NASA Glenn Research Center to ultimately provide a large- eddy simulation capability that is both accurate and efficient for complex aeropropulsion flows. The FR approach offers a simple and efficient method that is easy to implement and accurate to an arbitrary order on common grid cell geometries. The governing compressible Navier-Stokes equations are discretized in time using various explicit Runge-Kutta schemes, with the default being the 3-stage/3rd-order strong stability preserving scheme. The code is written in modern Fortran (i.e., Fortran 2008) and parallelization is attained through MPI for execution on distributed-memory high-performance computing systems. An h- refinement study of the isentropic Euler vortex problem is able to empirically demonstrate the capability of the FR method to achieve super-accuracy for inviscid flows. Additionally, the code is applied to the Taylor-Green vortex problem, performing numerous implicit large-eddy simulations across a range of grid resolutions and solution orders. The solution found by a pseudo-spectral code is commonly used as a reference solution to this problem, and the FR code is able to reproduce this solution using approximately the same grid resolution. Finally, an examination of the code's performance demonstrates good parallel scaling, as well as an implementation of the FR method with a computational cost/degree- of-freedom/time-step that is essentially independent of the solution order of accuracy for structured geometries.

High-Order Methods↗

NASA NTRS2004

In Situ Location and Characterization of Carbon-bearing Phases in Carbonaceous Chondrites: Insights from Yamato 791198, a Weakly-altered CM2 Chondrite

Intense studies of carbonaceous chondrites have provided remarkable insights into the behavior of carbon during the earliest stages of our solar system. This research has demonstrated that carbonaceous meteorites contain a diverse array of organic compounds, whose origins are probably the result of multiple processes that occurred in different locations including interstellar space, the solar nebula and asteroidal parent bodies [1-3]. The most abundant organic carbon component in CI1 and CM2 carbonaceous chondrites is so-called macromolecular carbon, a high molecular weight material that has some affinities to terrestrial kerogen and constitutes approximately 60-70% of the organic material in these meteorites. Although recent studies e.g. [3] have radically improved our understanding of the structural and compositional characteristics of this material, a number of key questions remain to be addressed. In particular, our knowledge of where this macromolecular material is distributed at the fine-scale within carbonaceous chondrites is scant. [4] have shown that organic material is associated with phyllosilicate-rich matrix in CM chondrites, but the detailed mineralogical associations are not well-known. Over the past 2 years, we have begun to address this question by using energy filtered transmission electron microscopy (EFTEM) to locate carbon-bearing materials in situ, focusing specifically on the CM2s. To date we have reported data on the Murchison CM2 chondrite [5], a meteorite that has experienced a modest degree of aqueous alteration. To extend our observations to other CM2 chondrites, we have examined the occurrence of carbon-bearing phases in Yamato 791198. Our recent studies [5] have shown that Y-791198 is among the most weakly-altered CM chondrite currently known and hence is likely to preserve a quite primitive distribution of carbonaceous material. In this study, we present initial observations on the distribution of these materials in one fine-grained rim and compare them with our results from Murchison. Such information may provide important insights into the origins of the carbonaceous material and how it was distributed in nebular and perhaps presolar dust.

Brearley, Adrian J.↗

NASA NTRS2022

Ultraviolet Photooxidation of Smectite-Bound Fe(II) and Implications for the Origin of Martian Nontronites

Clay minerals detected with orbital and in situ instruments in ancient Martian terrains constrain Mars' climate and aqueous alteration history. Early in its history, Mars experienced an atmospheric redox change and iron-bearing clay minerals may preserve the effects of that transition. Ferrous smectites, the thermodynamically predicted product of chemical weathering of basalts under anoxic conditions, may have undergone oxidation by exposure to chemical oxidants in the atmosphere or regolith, or by direct photooxidation at the surface. To assess these potential oxidation pathways, ferrous trioctahedral smectites of varying initial iron content were synthesized and subjected to oxidation by ultraviolet (UV) irradiation. Experimental UV irradiation under an anoxic atmosphere equivalent to approximately 7 years of flux on the Martian surface caused partial oxidation of smectite-bound Fe (Fe3+/ΣFe = 16–18%) and octahedral sheet contraction. Metal-OH vibrational bands in visible/near infrared (VNIR) reflectance spectra of oxidized smectites changed in band depth and asymmetry with higher iron content. X-ray diffraction patterns of UV irradiated samples indicate the formation of a mixed di- and trioctahedral smectite or a secondary nontronite phase, possibly on the surfaces of higher iron content smectites. These experiments suggest that UV irradiation is able to oxidize structurally bound iron in smectites without the presence of other chemical oxidants. Photooxidation may have influenced the mineralogy, both syndepositionally and postdepositionally, of Martian alteration assemblages formed near the surface and this process needs not be limited to one part of their formation history. Plain Language Summary: Martian mineral assemblages observed with orbiters and rover instruments allow us to understand the planet's past climate and aqueous activity. Hydrated minerals that contain Fe(II) are of particular interest as they would have been affected by the early atmosphere becoming more oxidizing overtime, changing the structural iron into Fe(III). In this study, we synthesized Fe(II) smectites with varying iron content and irradiated them with an ultraviolet (UV) light source to test whether they could be photooxidized. Iron in the smectite minerals was incompletely oxidized by UV radiation after being exposed for the equivalent of approximately 7 years of exposure on the early Mars surface. The smectites with higher iron content showed more changes with photooxidation in their visible/near infrared spectra as well as in their X-ray diffraction patterns, two datasets collected by instruments on currently active Martian missions. These results suggest that UV photooxidation is a plausible contributor to the mineralogy and redox state of clay mineral assemblages observed at the Martian surface.

V. B. Rivera Banuchi↗

NASA NTRS2002

Sulfur Saturation Limits in Silicate Melts and their Implications for Core Formation Scenarios for Terrestrial Planets

This study explores the controls of temperature, pressure, and silicate melt composition on S solubility in silicate liquids. The solubility of S in FeO-containing silicate melts in equilibrium with metal sulfide increases significantly with increasing temperature but decreases with increasing pressure. The silicate melt structure also exercises a control on S solubility. Increasing the degree of polymerization of the silicate melt structure lowers the S solubility in the silicate liquid. The new set of experimental data is used to expand the model of Mavrogenes and O'Neill(1999) for S solubility in silicate liquids by incorporating the influence of the silicate melt structure. The expected S solubility in the ascending magma is calculated using the expanded model. Because the negative pressure dependence of S solubility is more influential than the positive temperature dependence, decompression and adiabatic ascent of a formerly S-saturated silicate magma will lead to S undersaturation. A primitive magma that is S-saturated in its source region will, therefore, become S-undersaturated as it ascends to shallower depth. In order to precipitate magmatic sulfides, the magma must first cool and undergo fractional crystallization to reach S saturation. The S content in a metallic liquid that is in equilibrium with a magma ocean that contains approx. 200 ppm S (i.e., Earth's bulk mantle S content) ranges from 5.5 to 12 wt% S. This range of S values encompasses the amount of S (9 to 12 wt%) that would be present in the outer core if S is the light element. Thus, the Earth's proto-mantle could be in equilibrium (in terms of the preserved S abundance) with a core-forming metallic phase.

Holzheid, Astrid↗

NASA NTRS1994

Baroreflex failure in a patient with central nervous system lesions involving the nucleus tractus solitarii

Animal studies have shown the importance of the nucleus tractus solitarii, a collection of neurons in the brain stem, in the acute regulation of blood pressure. Impulses arising from the carotid and aortic baroreceptors converge in this center, where the first synapse of the baroreflex is located. Stimulation of the nucleus tractus solitarii provides an inhibitory signal to other brain stem structures, particularly the rostral ventrolateral medulla, resulting in a reduction in sympathetic outflow and a decrease in blood pressure. Conversely, experimental lesions of the nucleus tractus solitarii lead to loss of baroreflex control of blood pressure, sympathetic activation, and severe hypertension in animals. In humans, baroreflex failure due to deafferentation of baroreceptors has been previously reported and is characterized by episodes of severe hypertension and tachycardia. We present a patient with an undetermined process of the central nervous system characterized pathologically by ubiquitous infarctions that were particularly prominent in the nucleus tractus solitarii bilaterally but spared the rostral ventrolateral medulla. Absence of a functioning baroreflex was evidenced by the lack of reflex tachycardia to the hypotensive effects of sodium nitroprusside, exaggerated pressor responses to handgrip and cold pressor test, and exaggerated depressor responses to meals and centrally acting alpha 2-agonists. This clinicopathological correlate suggests that the patient's baroreflex failure can be explained by the unique combination of the destruction of sympathetic inhibitory centers (ie, the nucleus tractus solitarii) and preservation of centers that exert a positive modulation on sympathetic tone (ie, the rostral ventrolateral medulla).

Non-NASA Center↗

NASA NTRS1998

Low Dissipative High Order Shock-Capturing Methods using Characteristic-Based Filters

An approach which closely maintains the non-dissipative nature of classical fourth or higher- order spatial differencing away from shock waves and steep gradient regions while being capable of accurately capturing discontinuities, steep gradient and fine scale turbulent structures in a stable and efficient manner is described. The approach is a generalization of the method of Gustafsson and Olsson and the artificial compression method (ACM) of Harten. Spatially non-dissipative fourth or higher-order compact and non-compact spatial differencings are used as the base schemes. Instead of applying a scalar filter as in Gustafsson and Olsson, an ACM like term is used to signal the appropriate amount of second or third-order TVD or ENO types of characteristic based numerical dissipation. This term acts as a characteristic filter to minimize numerical dissipation for the overall scheme. For time-accurate computations, time discretizations with low dissipation are used. Numerical experiments on 2-D vortical flows, vortex-shock interactions and compressible spatially and temporally evolving mixing layers showed that the proposed schemes have the desired property with only a 10% increase in operations count over standard second-order TVD schemes. Aside from the ability to accurately capture shock-turbulence interaction flows, this approach is also capable of accurately preserving vortex convection. Higher accuracy is achieved with fewer grid points when compared to that of standard second-order TVD or ENO schemes. To demonstrate the applicability of these schemes in sustaining turbulence where shock waves are absent, a simulation of 3-D compressible turbulent channel flow in a small domain is conducted.

Yee, H. C.↗

NASA NTRS1998

Low Dissipative High Order Shock-Capturing Methods Using Characteristic-Based Filters

An approach which closely maintains the non-dissipative nature of classical fourth or higher- order spatial differencing away from shock waves and steep gradient regions while being capable of accurately capturing discontinuities, steep gradient and fine scale turbulent structures in a stable and efficient manner is described. The approach is a generalization of the method of Gustafsson and Oisson and the artificial compression method (ACM) of Harten. Spatially non-dissipative fourth or higher-order compact and non-compact spatial differencings are used as the base schemes. Instead of applying a scalar filter as in Gustafsson and Olsson, an ACM like term is used to signal the appropriate amount of second or third-order TVD or ENO types of characteristic based numerical dissipation. This term acts as a characteristic filter to minimize numerical dissipation for the overall scheme. For time-accurate computations, time discretizations with low dissipation are used. Numerical experiments on 2-D vortical flows, vortex-shock interactions and compressible spatially and temporally evolving mixing layers showed that the proposed schemes have the desired property with only a 10% increase in operations count over standard second-order TVD schemes. Aside from the ability to accurately capture shock-turbulence interaction flows, this approach is also capable of accurately preserving vortex convection. Higher accuracy is achieved with fewer grid points when compared to that of standard second-order TVD or ENO schemes. To demonstrate the applicability of these schemes in sustaining turbulence where shock waves are absent, a simulation of 3-D compressible turbulent channel flow in a small domain is conducted.

Yee, H. C.↗

NASA NTRSDate not supplied

Multiscale Modeling of Reconstructed Tricalcium Silicate using NASA Multiscale Analysis Tool

To study microstructure characteristics of cementitious materials hydrated in space; previously, cement binder formations were processed under microgravity conditions and was further compared against ground-based experiments. For accurate estimation of process-structure-property linkage, particularly on samples hydrated in the microgravity environment, it is desired to have a high-fidelity volumetric representation of the microstructure. However, owing to small sample size and high porosity of the space-returned samples, conventional experimental characterization techniques are not viable. Hence, a deep learning-based reconstruction algorithm was employed to obtain high fidelity 3D volumes from sparse high resolution 2D Scanning Electron Microscopy (SEM) images, as inputs to micromechanics-based modeling. This machine learning-based reconstruction methodology validated against low-order statistical descriptors, captured the microstructural topology of both sample types (ground, 1g and microgravity, μg). Due to the lack of gravity, hydration products of the samples processed in space differed from those processed-on ground. Such AI-generated virtual samples were analyzed in a multiscale recursive micromechanics approach using the NASA Multiscale Analysis Tool (NASMAT). Here, we present a methodology to rapidly integrate and evaluate these AI-generated volumes in NASMAT. The synthesized microstructural volumes are directly employed as Representative Volume Elements (RVEs) to preserve the fidelity (1 pixel = 0.54 m). Invariably, analysis of such largescale problems (5123 voxels) requires huge amount of computational resources. By taking advantage of the NASMAT architecture, we also focused on systematic multiscale integration of these AI-reconstructed virtual volumes to reduce the computational demands. In this work, this methodology is demonstrated on the ground-based, 1g samples. The estimated stiffness value of 15.90 GPa is comparable to experimentally obtained modulus of hydrated tricalcium silicate sample. The workflow presented here paves the way for utilizing the NASMAT tool to perform multiscale analyses of other multi-phase material systems using either 3D virtual datasets synthesized using AI or obtained via micro-CT.

Machine Learning↗

NASA NTRS2010

Mission Control Center/Building 30. Historical Documentation

As part of this nation-wide study, in September 2006, historical survey and evaluation of NASA-owned and managed facilities was conducted by NASA's Lyndon B. Johnson Space Center (JSC) in Houston, Texas. The results of this study are presented in a report entitled, Survey and Evaluation of NASA-owned Historic Facilities and Properties in the Context of the U.S. Space Shuttle Program, Lyndon B. Johnson Space Center, Houston, Texas, prepared in November 2007 by NASA JSC s contractor, Archaeological Consultants, Inc. As a result of this survey, the Mission Control Center (Building 30) was determined eligible for listing in the NRHP, with concurrence by the Texas State Historic Preservation Officer (SHPO). The survey concluded that Building 30 is eligible for the NRHP under Criteria A and C in the context of the U.S. Space Shuttle Program (1969-2010). Because it has achieved significance within the past 50 years, Criteria Consideration G applies. It should be noted that the Mission Control Center was designated a National Historic Landmark in 1985 for its role in the Apollo 11 Lunar Landing. At the time of this documentation, Building 30 was still used to support the SSP as an engineering research facility, which is also sometimes used for astronaut training. This documentation package precedes any undertaking as defined by Section 106 of the NHPA, as amended, and implemented in 36 CFR Part 800, as NASA JSC has decided to proactively pursue efforts to mitigate the potential adverse affects of any future modifications to the facility. It includes a historical summary of the Space Shuttle program; the history of JSC in relation to the SSP; a narrative of the history of Building 30 and how it supported the SSP; and a physical description of the structure. In addition, photographs documenting the construction and historical use of Building 30 in support of the SSP, as well as photographs of the facility documenting the existing conditions, special technological features, and engineering details, are included. A contact sheet printed on archival paper, and an electronic copy of the work product on CD, are also provided.

Source record↗

NASA NTRS2008

Modifying the Heliophysics Data Policy to Better Enable Heliophysics Research

The Heliophysics (HP) Science Data Management Policy, adopted by HP in June 2007, has helped to provide a structure for the HP data lifecycle. It provides guidelines for Project Data Management Plans and related documents, initiates Resident Archives to maintain data services after a mission ends, and outlines a route to the unification of data finding, access, and distribution through Virtual observatories. Recently we have filled in missing pieces that assure more coherence and a home for the VxOs (through the 'Heliophsyics Data and Model Consortium'), and provide greater clarity with respect to long term archiving. In particular, the new policy which has been vetted with many community members, details the 'Final Archives' that are to provide long-term data access. These are distinguished from RAs in that they provide little additional service beyond servicing data, but critical to their success is that the final archival materials include calibrated data in useful formats such as one finds in CDAWeb and various ASCII or FITS archives. Having a clear goal for legacy products, to be detailed as part of the Mission Archives Plans presented at Senior Reviews, will help to avoid the situation so common in the past of having archival products that preserve bits well but not readily usable information. We hope to avoid the need for the large numbers of 'data upgrade' projects that have been necessary in recent years.

Hayes, Jeffrey↗

NASA NTRS2011

Evolution of the Space Shuttle Primary Avionics Software and Avionics for Shuttle Derived Launch Vehicles

As a result of recommendation from the Augustine Panel, the direction for Human Space Flight has been altered from the original plan referred to as Constellation. NASA s Human Exploration Framework Team (HEFT) proposes the use of a Shuttle Derived Heavy Lift Launch Vehicle (SDLV) and an Orion derived spacecraft (salvaged from Constellation) to support a new flexible direction for space exploration. The SDLV must be developed within an environment of a constrained budget and a preferred fast development schedule. Thus, it has been proposed to utilize existing assets from the Shuttle Program to speed development at a lower cost. These existing assets should not only include structures such as external tanks or solid rockets, but also the Flight Software which has traditionally been a "long pole" in new development efforts. The avionics and software for the Space Shuttle was primarily developed in the 70 s and considered state of the art for that time. As one may argue that the existing avionics and flight software may be too outdated to support the new SDLV effort, this is a fallacy if they can be evolved over time into a "modern avionics" platform. The technology may be outdated, but the avionics concepts and flight software algorithms are not. The reuse of existing avionics and software also allows for the reuse of development, verification, and operations facilities. The keyword is evolve in that these assets can support the fast development of such a vehicle, but then be gradually evolved over time towards more modern platforms as budget and schedule permits. The "gold" of the flight software is the "control loop" algorithms of the vehicle. This is the Guidance, Navigation, and Control (GNC) software algorithms. This software is typically the most expensive to develop, test, and verify. Thus, the approach is to preserve the GNC flight software, while first evolving the supporting software (such as Command and Data Handling, Caution and Warning, Telemetry, etc.). This can be accomplished by gradually removing the "support software" from the legacy flight software leaving only the GNC algorithms. The "support software" could be re-developed for modern platforms, while leaving the GNC algorithms to execute on technology compatible with the legacy system. It is also possible to package the GNC algorithms into an emulated version of the original computer (via Field Programmable Gate Arrays or FPGAs), thus becoming a "GNC on a Chip" solution where it could live forever to be embedded in modern avionics platforms.

Ferguson, Roscoe C.↗

NASA NTRS2016

Preserving, Enhancing, and Continuing the Scientific Legacy of the Apollo Sample Suite

From 1969 to 1972, Apollo astronauts collected 382 kg of rocks, soils, and core samples from six geologically diverse locations on the Moon. In the nearly 50 years since the samples were collected, over 3000 different studies have been conducted using the nearly 2200 different Apollo samples. Despite the maturity of the sample collection, many new studies of lunar samples are undertaken each year, with an average of more than 55 requests and more than 600 distinct subsamples allocated annually over the past five years. The Apollo samples are a finite resource, however. Although new studies are encouraged, it is important that new studies do not duplicate previous studies, and where possible, leverage previous results to inform and enhance the current studies. This helps to preserve the samples and scientific funding, both of which are precious resources. We have initiated several new efforts to rescue some of the early analyses from these samples, including unpublished analytical data. We are actively scanning NASA documentation in paper form that is related to the Apollo missions and sample processing, and we are collaborating with IEDA to establish a geochemical data base called MoonDB. To populate this database, we are actively working with about a dozen prominent lunar PIs to organize and transcribe years of both published and unpublished data, making it available to all researchers. This effort will also take advantage of new online analytical tools like PetDB. There have already been tangible results from the MoonDB data rescue effort. A pilot project involving the rescue of geochemical data of John Delano on Apollo pyroclastic glasses has already been referenced in multiple Apollo sample requests, and in fact, the compiled data was used as part of one of the new studies. Similarly, scanned sample handling reports have been utilized to find previously analyzed samples that were appropriate to fulfill new sample requests. We have also begun to image the Apollo samples using (1) micro‐CT scanning to document the interior structure of samples, and (2) comprehensive high resolution photography of samples, enabling high resolution 3D reconstructions of the samples. Both efforts will provide comprehensive access to these samples and allow for more targeted requests, and thus better curation of the samples for decades to come.

Zeigler, Ryan↗