Engineering Papers⌕ Search

SEARCH · Engineering Papers

Results for “dehydration”

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.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

464 records · Page 26
All sourcesNASA NTRSDOE OSTI
NASA NTRSDate not supplied

Understanding the Heating Kinetics of Asteroid Ryugu By Comparison to Naturally and Experimentally Heated Meteorites

The Hayabusa2 mission visited the near-Earth Cb-type asteroid (162173) Ryugu and has returned to Earth surface material of Ryugu. Ryugu is an airless rubble pile asteroid exposed to space weathering [1]. Visible and near infrared remote observations recorded an absorption feature at 2.72 μm indicating the presence of OH– bearing hydrous components. The weak 2.72 μm feature suggested that Ryugu was once organic- and water-rich and subsequently dehydrated by a brief period of surficial heating with resemblance to “thermally metamorphosed carbonaceous chondrites”, “CI-/CM-like”, or “CY” chondrites [2, 3]. However, initial examination of the returned samples did not identify any significant heating of >150 °C [4, 5], and contrastingly, amino acid analysis of Ryugu samples suggested similarities to thermally-altered meteorites on the grounds of the predominant straight-chain n-ω-amino acid abundances [6]. In this study, we aim at addressing the nonconformal interpretations to the thermal history of Ryugu by comparing the organic composition of fresh Ryugu samples to that of chondritic meteorites that have been naturally (long-term radiogenic thermal metamorphism and short-term heating) and experimentally heated.

Q. H. S. Chan↗
NASA NTRSDate not supplied

Formation of Tropopause Cirrus clouds by Typhoon-induced gravity waves during the Asian Summer Monsoon: A Case Study from the BATAL 2017 Campaign

Cirrus clouds in the Tropical Tropopause Layer (TTL) have a net warming impact on Earth’s climate and they regulate the amount of water vapor entering the lower stratosphere through dehydration process near the cold-point tropopause. During the Boreal summer, Asian Summer Monsoon (ASM) is an important source of cirrus clouds and humidity in the TTL owing to frequent deep convection. However, better representation of convection and TTL cirrus clouds in global climate models is needed for accurate assessment of their response to changing climate. In this study, we investigate the mechanisms involved in the formation of a tropopause cirrus cloud layer observed during the Balloon measurement campaigns of the Asian Tropopause Aerosol Layer (BATAL) over Hyderabad (17.47 °N, 78.58 °E), India on 23 August 2017. A subvisible cirrus cloud layer (optical thickness ~0.025) was detected by a backscatter sonde (COBALD) onboard a balloon near the cold-point tropopause (CPT, temperature~ -86.4 ° C, altitude~17.9 km) which was later confirmed by the CATS lidar on the ISS. Simultaneous measurements from an optical particle counter (Boulder Counter) revealed the presence of ice crystals smaller than 50 microns in this layer. The formation mechanism responsible for this tropopause cirrus is investigated using a technique combining three-dimensional back-trajectories, satellite observations, and ERA5 reanalysis data. Satellite observations revealed that the overshooting convection associated with a category-3 typhoon Hato, which hit Macau and Hong Kong on 23 August 2017 injected ice into the lower stratosphere. This caused a hydration patch that followed the ASM anticyclone subsequently moving towards Hyderabad. The presence of tropopause cirrus cloud layers in the cold temperature anomalies and updrafts along the back-trajectories indicated towards the role of typhoon-induced gravity waves in their formation. This case study highlights the role of typhoons in influencing the formation of tropopause cirrus clouds through stratospheric hydration and gravity waves in the ASM anticyclone.

Amit Kumar Pandit↗
NASA NTRSDate not supplied

Asteroid (142) Polana at 3 µM and Its Linkage to the Primitive Asteroid (101955) Bennu

The Polana family is a low-albedo family located at a low inclination and a semimajor axis of ~2.42 au in the inner main asteroid belt. This family is likely the source of primitive near-Earth asteroids, including the OSIRIS-REx mission target (101955) Bennu. The B-type asteroid 142 Polana is the largest remnant of the "New Polana" family, and it has been spectrally (~0.5-2.5 µm) and dynamically linked to Bennu. Here, we investigate the compositional linkage of asteroids Polana and Bennu using spectra measured at longer wavelengths (~1.6-4.0 µm), which cover the 3- µm band. Polana’s spectra were measured at NASA IRTF using the LXD mode of SpeX. Bennu’s spectra were measured by OSIRIS-REx’s OVIRS spectrometer and revealed that this primitive asteroid is hydrated consistent with CM, CI, or CR carbonaceous chondrites. Polana’s LXD spectra, on the hand, show that the parent body of the Polana family is not hydrated (i.e., no absorption band at ~ 3.0 µm). Additionally, Polana’s LXD spectra do not indicate the presence of organics and/or carbonates. Polana's lack of significant water, organic, and carbonate spectral features on its surface could be related to the degree of heating in the Polana family-forming event and the reaccretion of ejecta that contributed to additional heating. The Polana family-forming event could also expose the parent body's dehydrated, organic/carbonate-poor interior. These results will be placed in the context of other low-albedo families and background objects in the inner main belt. An approved JWST program to observe Polana (with both NIRSpec and MIRI) will be able to assess if there is a Ryugu-like band and should allow a comparison of the MIR spectrum to Bennu.

Driss Takir↗
NASA NTRSDate not supplied

Validation of A Sensorimotor Disorientation Ground Analog

INTRODUCTION Simulating the sensorimotor disorientation effects of gravity transitions after prolonged stays in microgravity is exceedingly challenging on Earth. In a previous study [1], a Sensorimotor Disorientation Analog (SDA) was developed based on subjective feedback from previously flown astronauts. The purpose of this study was to validate this SDA by comparing performance in movement tasks that have a wealth of spaceflight data against task performance while using the SDA. METHODS Thirty healthy non-astronaut subjects (17 males, 13 females; Mean ± SD, Age: 33.5 ± 7.2 years, Height: 68.0 ± 3.4 in, Weight: 164 ± 26 lbs.) volunteered to participate in this study. Subjects performed three movement tasks: computerized dynamic posturography (CDP), obstacle walk, and tandem walk. For CDP, subjects maintained an upright stance for 20s with eyes closed on an unstable pitch sway-referenced platform with head erect (sensory organization test (SOT)-5) and with head pitch ±20° to an auditory cue(SOT-5M). The obstacle walk involved a sit-to-stand with 10s of quiet stance followed by walking to and around a cone placed 4m away while navigating a 30cm obstacle to the cone and back. The tandem walk involved walking heel-to-toe for approximately 10-12 steps with eyes open and eyes closed. Subjects performed the three movement tasks under three levels of the SDA replicating different time points of recovery: none (preflight), low (Return (R)+24- 48hours), and high (R+0- 24hours). The SDA included galvanic vestibular stimulation (GVS) to disorient the vestibular system and a weighted suit (trunk, wrists, and ankles) to alter proprioceptive feedback and replicate subjective heaviness. RESULTS As the SDA magnitude increased, overall performance outcomes decreased. However, the ability of the SDA to replicate the range of astronaut postflight performance was task dependent. CDP SOT-5 performance across SDA levels closely replicated astronaut performance at all time points. SOT-5M, however, had minimal performance changes across SDA levels and was unable to replicate astronaut performance. The obstacle walk showed performance changes across SDA levels and matched astronaut performance preflight and at R+24-48hrs (low). Obstacle walk performance at the high SDA level was reduced in comparison to the low level; however, it was not replicative of astronaut performance immediately after landing. Last, tandem walk had distinct groupings of performance across SDA levels and was able to elicit a high level of disorientation consistent with R+0-24 hours (high) postflight performance for eyes open and eyes closed. The low SDA level for both eyes open and eyes closed was more disruptive than previous crewmember performance at the R+24-48 hours timepoint. CONCLUSION The SDA was developed to replicate postflight sensorimotor disruptions. However, it is well-known that immediately post-landing, astronauts can experience motion sickness, dehydration, fatigue, orthostatic intolerance, illusory sensations, lumbar pain, etc. This multi-system response to return to 1G varies widely across astronauts and, as such, it was not unexpected that the extreme ends of responses in the R+0-24hrs time period were the most difficult to replicate. These results suggest that the SDA levels are able to elicit distinct performance groupings and, although not able to perfectly replicate R+0-24hrs, the SDA did replicate a large range of performance after return to Earth.

S C Moudy↗
NASA NTRS2023

Phyllosilicate Decomposition on Bennu Due to Prolonged Surface Exposure

The Origins, Spectral Interpretation, Resource Identification, and Security–Regolith Explorer (OSIRIS-REx) mission to carbonaceous asteroid (101955) Bennu performed detailed mapping with a suite of instruments to characterize the composition and geology of its surface. Here we use data from the OSIRIS-REx Thermal Emission Spectrometer (OTES) instrument to investigate the relationship of OTES-derived spectral indices to other derived data products from OTES, the OSIRIS-REx Camera Suite (OCAMS), and the OSIRIS-REx Visible and InfraRed Spectrometer (OVIRS) at global and local scales. We quantitatively confirm that high values of the OTES silicate stretching slope (from ∼10 to ∼12 μm) in midday spectra that are indicative of thin and/or patchy dust cover are strongly associated with low thermal inertia (high porosity), low albedo boulders on Bennu. These high porosity boulders have brecciated textures with embedded clasts that likely originated on Bennu's parent body or during its disruption. The high porosity of these boulders is a key factor in the local production of the dust or its entrapment, as some large, brecciated boulders with a lower porosity have little evidence of dust. A second OTES spectral parameter, the silicate bending band depth near 22.7 μm applied to early evening spectra, is not correlated to thermal inertia, but is weakly to strongly correlated to albedo, OVIRS-derived 1.05 μm and 2.74 μm band depths, OVIRS-derived hydrogen abundance, and modeled nanophase troilite abundance. In several regions on Bennu there is a strong spatial relationship between these parameters, whereby areas with shallower silicate bending bands also have shallower 1.05 μm and 2.74 μm bands and lower albedo with higher nanophase troilite abundances. These correlations, combined with analysis of the silicate bending band in laboratory experiments of space weathered and mildly heated carbonaceous chondrites, suggests that decreased silicate bending band depths signify decomposition of phyllosilicates, likely Fe-bearing, due to space weathering or mild heating (<600 °C) via solar radiation during Bennu's time in near-Earth space. There is a strong association of larger silicate bending band depths in areas dominated by small rocks and unresolved material and in areas with small (≤ 25 m) craters identified as the spectrally reddest on Bennu, suggesting that this material has been more recently exposed due to impact and/or mass wasting processes. The shallowest silicate bending depths are associated with larger rocks and boulders that appear to have the longest surface exposure history, although there is band depth variation among them suggesting either initial composition variation that resulted in different responses to space weathering or heating, or varied exposure history of individual boulders themselves. We predict that any grains returned from Bennu with a significant surface exposure history will be characterized by shallower 22.7 μm, 1.05 μm and 2.7 μm band depths and increased sulfide (troilite) abundance, as well as textural and chemical evidence for phyllosilicate dehydration.

Asteroids, surfaces↗
NASA NTRSDate not supplied

Insights Into the CM Parent Body's Interior: A Comparative Study With Bennu's Bright Boulders

CM (Mighei-like) chondrites, primitive and water-rich asteroid samples from the early solar system, are significant for their potential role in delivering water and organic compounds to Earth [1-2]. Their resemblance to near-Earth asteroids Bennu and Ryugu, the targets of recent sample return missions, highlights their importance. What we learn from CM chondrites can be applied to these intriguing celestial bodies. Initial studies indicated that phyllosilicate-rich C chondrites underwent low-temperature aqueous alteration (<150°C) [3-5]. Subsequent research revealed that some experienced post-hydration thermal metamorphism at temperatures between ∼200°C and >750°C, resulting in dehydrated minerals and reduced volatile elements [6-9].This finding challenged the previous assumption that these chondrites had not undergone significant thermal metamorphism.

I Kerraouch↗
NASA NTRS2024

Evidence Report: Risk of Renal Stone Formation

Kidney stone formation and passage has the potential to greatly impact mission success and crewmember health, especially for long-duration missions. Alterations in hydration state (relative dehydration), spaceflight-induced changes in urine biochemistry (urine super-saturation), and bone metabolism (increased calcium excretion) during exposure to microgravity may increase the risk of kidney stone formation. There are possible countermeasures and treatments available that are used terrestrially that may then be applied to spaceflight. Directed Acyclic Graphs (DAGs) are used throughout this document to communicate spaceflight conditions that may lead to renal stone formation, the countermeasures that may be used to prevent their formation, and possible treatment modalities. The DAGs are sorted by strength of evidence, according to Table 6. Additionally, for the full Renal Stone Evidence Report Content: Directed Acyclic Graphs and Evidence Report, please see Appendix A, Expanded Directed Acyclic Graphs (DAGs) and Evidence. Additionally, a proposed Concept of Operations for the Prevention, Diagnosis, and Treatment of Renal Stones for a Mars Mission was created in conjunction with and to complement this Evidence Report update. Please see Appendix B, Proposed Expanded Concept of Operations for the Prevention, Diagnosis and Treatment of Renal Stones for Mars Missions, for the full report. Areas in the following Evidence Report will be cross-linked to scenarios from the Concept of Operations.

Emily Stratton↗
NASA NTRSDate not supplied

BioNutrients-3: Precision Fermentation, Pasteurization, and Pathogen Detection - Towards Safe Fermentation and Production of Nutrients in Space

The BioNutrients (BN) project is developing a microbial manufacturing approach to supplement the NASA food system to address known nutrient degradation associated with long-term storage. BN uses synthetic biology to deliver high-value nutrients and therapeutics through genetic engineering of microbes and production of fermented food products like yogurt and kefir, in a fully dehydrated system. On-demand production of nutrients for human consumption requires rigorous safety protocols to ensure contaminants are not introduced during the fermentation process. The third iteration of the BN flight project, BN-3, further develops the BN project by investigating strategies for pathogen detection and pasteurization in microgravity. BN-3 will test the limits of pathogen detection using whole genome sequencing, standard microbial assays and the NASA Ames E-Nose, a volatile carbon nano tube-based sensor array, to detect unwanted microbes. BN-3 also expands on the number of nutrients produced in a single bioreactor to enhance efficiency of the system by combining production of B vitamins in conjunction with the carotenoids, beta-carotene and zeaxanthin. Serial production of food products through yogurt passaging, new updates to the fluorinated ethylene propylene bags to allow crew access via a straw, as well as use of a food safe pH indicator dye to indicate readiness of the food product, will further enhance the useability of this system. This presentation will provide status of the BN-3 flight project with the aim of advancing in-space biomanufacturing for on-demand microbially based food production for future space exploration.

Biomanufacturing↗
NASA NTRS1999

Insects at low pressure: applications to artificial ecosystems and implications for global windborne distribution

Insects have a number of potential roles in closed-loop life support systems. In this study we examined the tolerance of a range of insect orders and life stages to drops in atmospheric pressure using a terrestrial atmosphere. We found that all insects studied could tolerate pressures down to 100 mb. No effects on insect respiration were noted down to 500 mb. Pressure toleration was not dependent on body volume. Our studies demonstrate that insects are compatible with plants in low-pressure artificial and closed-loop ecosystems. The results also have implications for arthropod colonization and global distribution on Earth.

Atmospheric Pressure↗