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All sourcesNASA NTRSDOE OSTI
NASA NTRS2025

Habitability and Human Factors Assessment (iSHORT, SHAQ, and SHU)

BACKGROUND As long-duration off-planet habitats become a reality, a consideration of habitability and human factors (HF) is crucial. The habitat is more than just a place to live and work. It is also the crew’s perception of the space, and the psychological impacts of size, layout, and usage over time; all of which can support or strain behavioral health and performance (BHP). A previous International Space Station (ISS) habitability study used the iSHORT (Space Habitability Observation Reporting Tool) to collect detailed data about habitability and human factors and inform NASA Standards. Of the previous iSHORT study, only one of the six ISS subjects had a duration of one year; all other ISS and ground analog subjects had shorter mission durations from one week to six months. It is necessary to collect new data with a focus on long-duration exploration missions of > 6 months and on planetary surface habitat design. New data is also needed to compare the iSHORT to other habitability measures. One measure, the SHAQ (Subjective Habitability and Acceptability Questionnaire), assesses the intersection of psychology and habitability. Another complementary measure, the Scale for Habitat Usability (SHU), is a brief subjective scale that captures how habitat design impacts perceived usability of the built environment in relation to task performance. OBJECTIVE Our study aims to (1) understand how individual well-being and team dynamics may relate to HF concerns over time, (2) capture how habitability and HF change over time, (3) compare the three habitability measures (iSHORT, SHAQ, SHU), (4) assess habitats to capture HF design concerns and related BHP impacts of a planetary habitat, and (5) inform future standards for HF design. METHOD Data are being collected on crews living and working in long-duration spaceflight analogs. Individual-level data collections are repeated at regular intervals throughout the missions on several habitat areas, activities, and key equipment (i.e., points of interest). These points of interest (POIs) include the kitchen/galley, crew quarters, and other work and living areas. Assessments include evaluations of privacy, comfort, convenience, control, efficiency, and social density through the lens of subsequent outcomes like sleep, individual performance, group activities performance, stress, mood, and social interactions. Pre- and post-mission evaluations will also allow comparison with homes, pre- and post-mission hotels, and a retrospective reflection of living and working in a long-duration analog. INITIAL DATA COLLECTIONS In this poster, we will describe the measures and data yield. Since the research protocol was designed, the study team has collected iSHORT Standalone four times, nine collections of SHAQ, and three collections of iSHORT with SHAQ. Data collection is ongoing. SUMMARY A novel assessment suite has been developed to further aid the comparison and complementary understanding of the habitability and human factors measures, which will allow for efficient deployment of these measures in analogs and/or spaceflight in near-term research as well as support well-being and performance through design.

J C W Miller↗
NASA NTRS2011

Validation of MODIS Aerosol Optical Depth Retrievals over a Tropical Urban Site, Pune, India

In the present paper, MODIS (Terra and Aqua; level 2, collection 5) derived aerosoloptical depths (AODs) are compared with the ground-based measurements obtained from AERONET (level 2.0) and Microtops - II sun-photometer over a tropical urban station, Pune (18 deg 32'N; 73 deg 49'E, 559 m amsl). This is the first ever systematic validation of the MODIS aerosol products over Pune. Analysis of the data indicates that the Terra and Aqua MODIS AOD retrievals at 550 nm have good correlations with the AERONET and Microtops - II sun-photometer AOD measurements. During winter the linear regression correlation coefficients for MODIS products against AERONET measurements are 0.79 for Terra and 0.62 for Aqua; however for premonsoon, the corresponding coefficients are 0.78 and 0.74. Similarly, the linear regression correlation coefficients for Microtops measurements against MODIS products are 0.72 and 0.93 for Terra and Aqua data respectively during winter and are 0.78 and 0.75 during pre-monsoon. On yearly basis in 2008-2009, correlation coefficients for MODIS products against AERONET measurements are 0.80 and 0.78 for Terra and Aqua respectively while the corresponding coefficients are 0.70 and 0.73 during 2009-2010. The regressed intercepts with MODIS vs. AERONET are 0.09 for Terra and 0.05 for Aqua during winter whereas their values are 0.04 and 0.07 during pre-monsoon. However, MODIS AODs are found to underestimate during winter and overestimate during pre-monsoon with respect to AERONET and Microtops measurements having slopes 0.63 (Terra) and 0.74 (Aqua) during winter and 0.97 (Terra) and 0.94 (Aqua) during pre-monsoon. Wavelength dependency of Single Scattering Albedo (SSA) shows presence of absorbing and scattering aerosol particles. For winter, SSA decreases with wavelength with the values 0.86 +/- 0.03 at 440 nm and 0.82 +/- 0.04 at 1020nm. In pre-monsoon, it increases with wavelength (SSA is 0.87 +/- 0.02 at 440nm; and 0.88 +/-0.04 at 1020 nm).

More, Sanjay↗
NASA NTRS2006

Spatial and Temporal Distribution of Cloud Properties Observed by MODIS: Preliminary Level-3 Results from the Collection 5 Reprocessing

The Moderate Resolution Imaging Spectroradiometer (MODIS) was developed by NASA and launched onboard the Terra spacecraft on December 18, 1999 and Aqua spacecraft on May 4, 2002. It achieved its final orbit and began Earth observations on February 24, 2000 for Terra and June 24, 2002 for Aqua. A comprehensive set of operational algorithms for the retrieval of cloud physical and optical properties (optical thickness, effective particle radius, water path, thermodynamic phase) have recently been updated and are being used in the new "Collection 5" processing stream being produced by the MODIS Adaptive Processing System (MODAPS) at NASA GSFC. All Terra and Aqua data are undergoing Collection 5 reprocessing with an expected completion date by the end of 2006. The archived products from these algorithms include 1 km pixel-level (Level-2) and global gridded Level-3 products. The cloud products have applications in climate change studies, climate modeling, numerical weather prediction, as well as fundamental atmospheric research. In this talk, we will summarize the available Level-3 cloud properties and their associated statistical data sets, and show preliminary Terra and Aqua results from the available Collection 5 reprocessing effort. Anticipated results include the latitudinal distribution of cloud optical and radiative properties for both liquid water and ice clouds, as well as joint histograms of cloud optical thickness and effective radius for selected geographical locations around the world.

King, Michael D.↗
NASA NTRSDate not supplied

Medical System Foundation Overview for Long-Duration Lunar Orbit and Surface Operations Missions

The Human Research Program (HRP) Exploration Medical Capability (ExMC) Element has developed a Medical System Foundation for Level of Care IV, as defined by NASA’s space flight human-system standards, for long-duration lunar orbit and surface operation missions by employing a systems engineering approach using model-based systems engineering tools. This Foundation model includes a concept of operations; functional decomposition; clinical content (medical conditions, capabilities, and resources); associated functional, interface and non-functional technical requirements; and traces to the current versions of NASA standards documents and parent-level (Program- and Vehicle habitat system level) requirements. Collectively, these components constitute a foundation that serves as a starting point for a medical system that meets the Level of Care IV requirement. The Foundation was developed by a multidisciplinary team consisting of systems engineers, scientists, and clinicians across NASA, and information is presented in an easily accessible format that is understandable across disciplines. Stakeholders can use the Foundation to analyze the traces between medical capabilities, medical conditions, medical resources, and requirements and to identify medical system interfaces with other vehicle systems/subsystems. It can also be used as a basis for performing trades on risks vs. medical system mass and volume allocation. This discussion will focus on the processes through which the Medical System Foundation was developed, how the Foundation builds a bridge between the medical and engineering domains and facilitates communication between these communities, and how these processes can be applied more broadly to a crew health and performance system and other system domains. The presentation also discusses Foundation modifications based on the recently updated versions of the NASA 3001 Standards.

S. Lumpkins↗
NASA NTRS1988

Space plasma contactor research, 1987

A simple model describing the process of electron collection from a low pressure ambient plasma in the absence of magnetic field and contactor velocity effects is presented. Experimental measurments of the plasma surrounding the contactor are used to demonstrate that a double-sheath generally develops and separates the ambient plasma from a higher density, anode plasma located adjacent to the contactor. Agreement between the predictions of the model and experimental measurements obtained at the electron collection current levels ranging to 1 A suggests the surface area at the ambient plasma boundary of the double-sheath is equal to the electron current being collected divided by the ambient plasma random electron current density; the surface area of the higher density anode plasma boundary of the double-sheath is equal to the ion current being emitted across this boundary divided by the ion current density required to sustain a stable sheath; and the voltage drop across the sheath is determined by the requirement that the ion and electron currents counterflowing across the boundaries be at space-charge limited levels. The efficiency of contactor operation is shown to improve when significant ionization and excitation is induced by electrons that stream from the ambient plasma through the double-sheath and collide with neutral atoms being supplied through the hollow cathode.

Wilbur, Paul J.↗
NASA NTRS1994

The Meteoritical Bulletin, no. 76, 1994 January: The U.S. Antarctic Meteoritie Collection

The Meteoritical Bulletin number 76 contains a list of all classified meteorites collected by the United States' Antarctic meteroite program as of the summer of 1993. The compilation includes available information on classification, mass, weathering, olivine and pyroxene composition, Al-26 activities, natural thermoluminescence levels, pairing, collection location and references to published descriptions for 5537 meteorite specimens. A list of the properties of metallic meteorites and a list of the most significant meteorites by class are also included.

Grossman, Jeffrey N.↗
NASA NTRS2002

Structure of the Highly Sheared Tropical Storm Chantal During CAMEX -4

On 20 August 2001 during the Convection and Moisture Experiment 4 (CAMEX-4) and NOAA Hurricane Field Program (HFP2001), the NASA high-altitude ER-2 and medium-altitude DC-8, and lower-altitude NOAA P3 aircraft conducted a coordinated Quantitative Precipitation Estimation (QPE) mission focused on convection in Tropical Storm Chantal. This storm first became a depression on 14 August, a tropical storm on 17 August, and it maintained maximum winds of about 65-70 mph during 19-20 August with minimum pressures ranging from 1008 mb on 19 August to 1001 mb late on 20 August. The storm was westward moving and was forecasted to intensify and landfall near the Yucatan-Belize border late on 20 August. Chanter failed to intensify and instead exhibited a highly sheared structure with an open low-level circulation and intense convection well to the northeast of this circulation center. The NASA ER-2 and DC-8 aircraft were closely coordinated with the NOAA P3 (NOAA-42). The NASA aircraft collected remote sensing and in situ data sets, while the P3 collected lower level in situ and radar data; both the DC-8 and P3 released 7 and 24 dropsondes, respectively. These aircraft measurements provided a unique opportunity to examine the structure of a sheared system and why it did not develop as forecasted a few days earlier. This paper will describe a preliminary study of the precipitation and wind structure provided by the NASA aircraft within the context of the NOAA P3 measurements.

Heymsfield, Gerald M.↗
NASA NTRS2014

Unmanned Aircraft System (UAS) Delegation of Separation in NextGen Airspace

The purpose of this study was to determine the feasibility of unmanned aircraft systems (UAS) performing delegated separation in the national airspace system (NAS). Delegated separation is the transfer of responsibility for maintaining separation between aircraft or vehicles from air navigation service providers to the relevant pilot or flight operator. The effects of delegated separation and traffic display information level were collected through performance, workload, and situation awareness measures. The results of this study show benefits related to the use of conflict detection alerts being shown on the UAS operator's cockpit situation display (CSD), and to the use of full delegation. Overall, changing the level of separation responsibility and adding conflict detection alerts on the CSD was not found to have an adverse effect on performance as shown by the low amounts of losses of separation. The use of conflict detection alerts on the CSD and full delegation responsibilities given to the UAS operator were found to create significantly reduced workload, significantly increased situation awareness and significantly easier communications between the UAS operator and air traffic controller without significantly increasing the amount of losses of separation.

NextGen↗
NASA NTRS1994

Collection requirements for trace-element analyses of extraterrestrial samples

Trace-element abundances have proven important in understanding the evolution of and interrelationships between different meteorites. Preliminary investigations of the trace-element contents of interplanetary dust particles indicate that trace-element abundances will prove equally important in distinguishing between micrometeorites of different types, comparing the interplanetary dust to the meteorites, and assessing the degree of thermal alteration experienced either on the parent body or during the collection process. Sample collection, delivery, and curation must be accomplished in a manner to avoid contamination with even trace amounts of the elements to be analyzed. The present SXRF sensitivity for micrometeorite analysis is of order 1 femtogram, but anticipated improvements in sensitivity will require sample contamination substantially below this level. Sample collection and handling equipment should be constructed from materials selected for ultrahigh purity, and serious consideration should be given in selecting the particular set of elements from which the collection apparatus is composed so as not to compromise useful information.

Flynn, George J.↗
NASA NTRS2023

Impact of Satellite Orbit Drift on Modis Earth Scene Observations Used in Calibration of the Reflective Solar Bands

After more than 20 years in orbit, NASA’s Terra and Aqua satellites have both started drifting away from their historically maintained orbits. The MODIS instruments on Terra and Aqua continue to collect valuable Earth observation data, but the changing orbits present a challenge for maintaining accurate calibration. The MODIS reflective solar bands (RSB), spanning the wavelength range from 412 nm to 2130 nm, are calibrated on orbit using a combination of regular data collections from an on-board solar diffuser, the Moon, and pseudo-invariant Earth scenes. Starting in the Collection 6 Level 1B (L1B) data products, the RSB calibration began using data from desert targets for a few of the visible bands to better track changes in the response versus scan angle that could not be captured by the on-board calibration. The use of Earth scene data has been extended recently for Terra MODIS calibration in Collection 6.1 (C6.1) and the upcoming Collection 7 (C7) L1B to also include data from ocean scenes and deep convective clouds (DCC). Drifts in both the orbit inclination and ground track of Terra and Aqua lead to changes in the solar illumination angles and satellite view angles of the Earth scenes. We discuss how these orbital changes impact the desert and DCC targets used for MODIS RSB calibration and present the accompanying changes made to our C6.1 and C7 calibration algorithms. We also discuss remaining future challenges, such as better characterization of bi-directional reflectance distribution functions, and possible alternative calibration strategies.

MODIS↗
NASA NTRS1994

Variation of Great Lakes Water Levels Derived from Geosat Altimetry

A technique for using satellite radar altimetry data to estimate the temporal variation of the water level in moderate to large lakes and enclosed seas is described. Great Lakes data from the first 2 years of the U.S. Navy's Geosat Exact Repeat Mission (November 1986 to November 1988), for which there is an improved orbit, are used to demonstrate the technique. The Geosat results are compared to the lake level data collected by the Great Lakes Section, National Ocean Service, National Oceanic and Atmospheric Administration, and are found to reproduce the temporal variations of the five major lakes with Root-Mean-Square error (RMS) ranging from 9.4 to 13.8 cm and a combined average of 11.1 cm. Geosat data are also analyzed for Lake St. Clair, representing a moderate-sized lake, with a resulting rms of 17.0 cm. During this study period, the water level in the Great Lakes varied in a typical annual cycle of about 0.2 m (0.5 in for Lake Ontario) superimposed on a general decline of approximately 0.5 m. The altimeter data reproduced the general decline reasonably well for all the lakes, but the annual cycle was obscured in some lakes due to systematic errors in the altimeter data. Current and future altimetry missions will have markedly improved accuracy which will permit many moderate (25 km diameter) or larger lakes or enclosed seas to be routinely monitored.

Morris, Charles S.↗
NASA NTRS1975

California coastal processes study: Skylab

The author has identified the following significant results. In San Pablo Bay, the patterns of dredged sediment discharges were plotted over a three month period. It was found that lithogenous particles, kept in suspension by the fresh water from the Sacramento-San Joaquin, were transported downstream to the estuarine area at varying rates depending on the river discharge level. Skylab collected California coastal imagery at limited times and not at constant intervals. Resolution, however, helped compensate for lack of coverage. Increased spatial and spectral resolution provided details not possible utilizing Landsat imagery. The S-192 data was reformatted; band by band image density stretching was utilized to enhance sediment discharge patterns entrainment, boundaries, and eddys. The 26 January 1974 Skylab 4 imagery of San Francisco Bay was taken during an exceptionally high fresh water and suspended sediment discharge period. A three pronged surface sediment pattern was visible where the Sacramento-San Joaquin Rivers entered San Pablo Bay through Carquinez Strait.

Pirie, D. M.↗
NASA NTRS1992

Performance assessment in complex individual and team tasks

Described here is an eclectic, performance based approach to assessing cognitive performance from multiple perspectives. The experience gained from assessing the effects of antihistamines and scenario difficulty on C (exp 2) decision making performance in Airborne Warning and Control Systems (AWACS) weapons director (WD) teams can serve as a model for realistic simulations in space operations. Emphasis is placed on the flexibility of measurement, hierarchical organization of measurement levels, data collection from multiple perspectives, and the difficulty of managing large amounts of data.

Eddy, Douglas R.↗
NASA NTRS1997

Immune alterations in male and female mice after 2-deoxy-D-glucose administration

Administration of 2-deoxy-D-glucose (2-DG) induces acute cellular glucoprivation. In the current study, we examined differences in immune parameters after 2-DG administration in both sexes. Male and female BDF1 mice were injected three times, 48 h apart, either with a saline solution (control group) or with 2-DG in saline (500 mg/kg). Two hours after the last injection, blood and spleens were collected. Plasma levels of interleukin-1beta, and interferon-gamma levels were measured. Additionally, the levels of the specific leukocyte antigens CD3, CD4, CD8, T cell receptor (TCR) alpha/beta, I-Ad, and H-2Ld/H-2Db were evaluated by flow cytometry on both blood and spleen cells. The blastogenic response of leukocytes from both tissues to mitogens was assessed. Levels of glucose, corticosterone, testosterone, progesterone, 17beta-estradiol, follicle-stimulating hormone, and luteinizing hormone were also determined. Increases in the percentage of cells bearing TCR alpha/beta and I-Ad in the blood and H-2Ld/H-2Db in the spleen were observed in the 2-DG-treated group for both sexes. In contrast, higher corticosterone and IL-1beta plasma concentrations, as well as higher percentages of splenocytes bearing TCR alpha/beta and I-Ad, and lower mitogen-induced proliferation of mature T splenocytes (79%) were observed in female but not in male mice injected with 2-DG compared with those injected with saline (p < 0.05). Taken together, these results suggest that female mice are more sensitive than male mice to immune alterations induced by 2-DG administration.

Non-NASA Center↗
NASA NTRS2004

Regional Comparison and Assimilation of GOCART and MODIS Aerosol Optical Depth across the Eastern U.S.

This study compares aerosol optical depths (AOD) products from the Moderate Resolution Imaging Spectroradiometer (MODIS) and the Goddard Chemistry Aerosol Radiation and Transport (GOCART) model and their integrated products with ground measurements across the eastern U.S. from March 1, 2000 to December 31, 2001. The Terra MODIS Level-3 (collection 4) AOD at 0.55 pm has better correlation, but consistently overestimates the values of the Aerosol Robotic Network (AERONET) measurements. GOCART has small biases for a 22-month integration, and slight positive biases are appeared for the cold season. These results are also supported by the comparison with the IMPROVE (Interagency Monitoring of Protected Visual Environments) light extinction index. The optimal interpolation improves the daily-scale RMSE from either MODIS or GOCART alone. However, the regional biases in the aerosol products constitute a major constraint to the optimal estimate of AOD.

Matsui, Toshihisa↗
NASA NTRS2010

Lidar Ratios for Dust Aerosols Derived From Retrievals of CALIPSO Visible Extinction Profiles Constrained by Optical Depths from MODIS-Aqua and CALIPSO/CloudSat Ocean Surface Reflectance Measurements

CALIPSO's (Cloud Aerosol Lidar Infrared Pathfinder Satellite Observations) analysis algorithms generally require the use of tabulated values of the lidar ratio in order to retrieve aerosol extinction and optical depth from measured profiles of attenuated backscatter. However, for any given time or location, the lidar ratio for a given aerosol type can differ from the tabulated value. To gain some insight as to the extent of the variability, we here calculate the lidar ratio for dust aerosols using aerosol optical depth constraints from two sources. Daytime measurements are constrained using Level 2, Collection 5, 550-nm aerosol optical depth measurements made over the ocean by the MODIS (Moderate Resolution Imaging Spectroradiometer) on board the Aqua satellite, which flies in formation with CALIPSO. We also retrieve lidar ratios from night-time profiles constrained by aerosol column optical depths obtained by analysis of CALIPSO and CloudSat backscatter signals from the ocean surface.

Young, Stuart A.↗
NASA NTRS2016

Cloud Regimes as a Tool for Systematic Study of Various Aerosol-Cloud-Precipitation Interactions

Systematic changes of clouds and precipitation are notoriously difficult to ascribe to aerosols. This presentation will showcase yet one more attempt to at least credibly detect the signal of aerosol-cloud-precipitation interactions. We surmise that the concept of cloud regimes (CRs) is appropriate to conduct such an investigation. Previous studies focused on what we call here dynamical CRs, and while we continue to adopt those too for our analysis, we have found that a different way of organizing cloud systems, namely via microphysical regimes is also promising. Our analysis relies on MODIS Collection 6 Level-3 data for clouds and aerosols, and TRMM-TMPA data for precipitation. The regimes are derived by applying clustering analysis on MODIS joint histograms, and once each grid cell is assigned a regime, aerosol and precipitation data can be spatiotemporally matched and composited by regime. The composites of various cloud and precipitation variables for high (upper quartile of distribution) and low (lower quartile) aerosol loadings can then be contrasted. We seek evidence of aerosol effects both in regimes with large fractions of deep ice-rich clouds, as well as regimes where low liquid phase clouds dominate. Signals can be seen, especially when the analysis is broken by land-ocean and when additional filters are applied, but there are of course caveats which will be discussed.

cloud regimes↗
NASA NTRS2016

Inter-Comparison of S-NPP VIIRS and Aqua MODIS Thermal Emissive Bands Using Hyperspectral Infrared Sounder Measurements as a Transfer Reference

This paper compares the calibration consistency of the spectrally-matched thermal emissive bands (TEB) between the Suomi National Polar-orbiting Partnership (S-NPP) Visible Infrared Imaging Radiometer Suite (VIIRS) and the Aqua Moderate Resolution Imaging Spectroradiometer (MODIS), using observations from their simultaneous nadir overpasses (SNO). Nearly-simultaneous hyperspectral measurements from the Aqua Atmospheric Infrared Sounder(AIRS) and the S-NPP Cross-track Infrared Sounder (CrIS) are used to account for existing spectral response differences between MODIS and VIIRS TEB. The comparison uses VIIRS Sensor Data Records (SDR) in MODIS five-minute granule format provided by the NASA Land Product and Evaluation and Test Element (PEATE) and Aqua MODIS Collection 6 Level 1 B (L1B) products. Each AIRS footprint of 13.5 km (or CrIS field of view of 14 km) is co-located with multiple MODIS (or VIIRS) pixels. The corresponding AIRS- and CrIS-simulated MODIS and VIIRS radiances are derived by convolutions based on sensor-dependent relative spectral response (RSR) functions. The VIIRS and MODIS TEB calibration consistency is evaluated and the two sensors agreed within 0.2 K in brightness temperature.Additional factors affecting the comparison such as geolocation and atmospheric water vapor content are also discussed in this paper.

Li, Yonghong↗