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NASA NTRS2025

Measuring Unique Contextual Factors: Group Living Skills

BACKGROUND The Human Factors and Behavioral Performance Exploration Measures (HFBP-EM) suite is a set of standardized measures used to assess behavioral health and performance risks related to future exploration-class space missions. During the HFBP-EM suite development, the importance of assessing unique contextual factors to understand the drivers of team dynamics was identified. Group living skills are a unique workplace skill which applies to those coworkers who live and work together. As mission lengths become longer, the line between work and non-work life may blur. Extreme living conditions such as spaceflight can result in increased stress over time, negatively impact mood and well-being, decrease team cohesion and increase conflict, deteriorate task performance, and potentially reduce mission success [1]. With no breaks in their isolated and confined environment possible, living with a messy, inconsiderate crewmember can add to the stress. Alternatively, crews with good group living skills may support one another, mitigating the negative effects of the extreme environment. There was no direct measure of group living skills. This work sought to fill this measurement gap and collect data related to group living in isolated, confined, extreme (ICE) environments. METHODS Group living skills as an astronaut competency area were developed with the input of experts familiar with ICE environments. Distinct aspects of this competency were reviewed and discussed by a NASA-invited group of spaceflight experts in 2015 to identify individual and team behavioral health and performance measures for operational environments. This work resulted in a 5-item measure focused on group living experiences with each crewmember (or the crew as a whole). A 6th item asks whether an individual would go on another mission with a particular crewmember or crew as a measure of future-oriented group living, or team viability. The measure was deployed in 24 teams living and working together in isolated and confined environments (e.g., International Space Station, space mission simulation analogs). RESULTS & DISCUSSION In this presentation, we will summarize results which indicate the Group Living Skills (GLS) Survey is a reliable, valid, and operationally feasible measure. Reliability was evaluated in several ways. Two-way multilevel mixed models revealed strong repeated measures reliability (ICC2 = .902, Omega between = .954). Reliability of change within teams was strong (Rc = .81). Factor analysis showed a consistent two-factor structure when individuals rated either the whole crew, all individuals, just peers, or a focal roommate. The latter used a sociometric approach to rating the GLS of the roommates. The two factors were tidiness and being considerate of others. We assessed the criterion-related validity of GLS, by examining GLS operationalized as the team-level aggregated GLS Survey scores as a predictor of team viability, team cohesion, and team performance. We used generalized mixed models to account for the repeated measures and longitudinal data. The marginal R2 change was used to determine the extent to which GLS were related to the team outcomes while controlling for mission day and campaign. Results suggested GLS was strongly related to team viability (marginal R2 change = .40), team cohesion (marginal R2 change = 0.28), social cohesion (marginal R2 change = 0.25), and moderately related to task cohesion (marginal R2 change = 0.18). GLS scores had a small relationship with team performance (marginal R2 change = .08). Results support GLS as a measure that can be used to capture group living skills of crews who live and work together in ICE. Because the items were written to be broadly applicable, less extreme environments with teams living and working together for some length of time also benefit from this measure (e.g., college roommates, camps). See Landon et al. (2024) for full results [2]. SUMMARY We report reliability and validity evidence for a new measure that assesses the Group Living Skills for teams that live and work in operational environments such as spaceflight.

J C W Miller↗
NASA NTRS1998

Human and team performance in extreme environments: Antarctica

Analogous experience is often instructive when attempting to understand human behavior in extreme environments. The current paper refers to the experiences of polar explorers and remote duty personnel to help identify the factors that influence individual and team performance when small groups are isolated and confined for long durations. The principal factors discussed include organizational structure, intracrew communications, interpersonal relations, leadership style, personnel selection, and training. Behavioral implications also are addressed for the design of procedures and equipment to facilitate sustained individual and group performance under conditions of isolation and confinement. To be consistent with the theme of the symposium, this paper emphasizes the crew requirements for an international expedition to Mars.

Non-NASA Center↗
NASA NTRS1963

Fusion Propulson System Requirements for an Interstellar Probe

An examination of the engine constraints for a fusion-propelled vehicle indicates that minimum flight times for a probe to a 5 light-year star will be approximately 50 years. The principal restraint on the vehicle is the radiator weight and size necessary to dissipate the heat which enters the chamber walls from the fusion plasma. However, it is interesting, at least theoretically, that the confining magnetic field strength is of reasonable magnitude, 2 to 3 x 10(exp5) gauss, and the confinement time is approximately 0.1 sec.

FUSION↗
NASA NTRS1971

Estimating carbon monoxide exposure

Method predicts effects of carbon monoxide on astronauts confined in spacecraft cabin atmospheres. Information on need for low toxicity level also applies to confined spaces. Benefits are applicable to industry and public health.

Edgerley, R. H.↗
NASA NTRS1971

Short term response of insulin, glucose, growth hormone and corticosterone to acute vibration in rats.

Study carried out to obtain some notion of the initial phasing and interactive effects among some hormones known to be responsive to vibration stress. Sprague-Dawley derived rats were exposed to the acute effects of confinement and confinement with lateral (plus or minus G sub y) vibration. The coincident monitoring of glucose, insulin, growth hormone, and corticosterone plasma levels, during and immediately subsequent to exposure to brief low level vibration, exhibits the effects of inhibition of insulin release by epinephrine. The ability of insulin (IRI) to return rapidly to basal levels, from appreciably depressed levels during vibration, in the face of elevated levels of glucose is also shown. Corticosterone responds with almost equal rapidity, but in opposite phase to the IRI. The immuno-assayable growth hormone (IGH) dropped from a basal level of 32 ng/ml to 7.3 ng/ml immediately subsequent to vibration and remained at essentially that level throughout the experiment (60 min). Whether these levels represent a real fall in the rat or whether they merely follow the immuno-logically deficient form is still in question.

Dolkas, C. B.↗
NASA NTRS1972

Rb-Sr age of a Luna 16 basalt and the model age of lunar soils.

An internal isochron was determined on a small basalt fragment (sample B-1) returned from the Luna 16 mission, which yields an age of 3.42 plus or minus 0.8 b.y. and a low initial Sr87/Sr86 value. A comparison is made of the data from four lunar missions to mare sites which shows that the last period of major flooding of the mare basins is confined to a narrow time interval of only 0.55 b.y. The direct evidence of major lunar magmatic activity appears to be confined to the interval from 3.1 to 4.0 b.y. The Sr87/Sr86 values for all mare basalts are extremely primitive and lie in a rather narrow range. A diagram is given for initial Sr87/Sr86 as a function of time for all lunar rocks.

Papanastassiou, D. A.↗
NASA NTRS1973

Study to validate the Non-Interference Performance Assessment (NIPA) technique

The NIPA (Non-Interference Performance Assessment) technique involves direct observation of group verbal activities by trained observers who rate the emotional content (affect) of each verbal interaction as either positive, negative, or neutral. During the test, in which four men were confined for 90 consecutive days, feasibility of the NIPA technique was demonstrated and observer reliability was verified. However, the validity of the test was not proved because an independent criterion measure of morale for the confined crew was lacking. There were indications, however, that NIPA measures were tracking changes in crew morale. At approximately the two-thirds point (Days 60 to 70), morale apparently fell dramatically for a period of about ten days, and simultaneously NIPA measure of positive verbalization decreased in number. A need was indicated for a separate study to apply the NIPA technique under experimental conditions and using a clearly defined criterion measure against which the ability of NIPA observations to truly measure morale changes could be determined.

Seeman, J. S.↗
NASA NTRS1973

Structural and lithologic study of northern coast ranges and Sacramento Valley, California

The author has identified the following significant results. Analysis of ERTS-1 imagery of the Northern California Coast Ranges has disclosed a potential relation between a heretofore unrecognized fracture system and known deposits of mercury and geothermally active areas in the Coast Range and between oil and gas fields in the Sacramento Valley. Three potentially important systems of linear elements within the Coast Ranges, detected on ERTS-1 imagery, may represent fault systems or zones of shearing because topographic offset and stratigraph disruption can be seen along one or two of the lineations. One of the systems in subparallel to the San Andreas fault and is confined to the Pacific Coastal Belt. Another set is confined to the central core of the Coast Ranges. The third set of linear features (Valley System) has not heretofore been recognized. Some of the known mercury deposits and geothermally active areas near Clear Lake, in the Coast Ranges, are along the Valley System or at the intersection of the Central and Valley Systems. The plotted locations of some of the oil and gas fields in the Sacramento Valley are associated with the Valley and/or Central Systems. If these relations prove reliable, the ERTS-1 imagery may prove to be an extremely useful exploration tool.

Rich, E. I.↗
NASA NTRS1973

Visual-motor response of crewmen during a simulated 90-day space mission as measured by the critical task battery

In order to test various components of a regenerative life support system and to obtain data on the physiological and psychological effects of long duration exposure to confinement in a space station atmosphere, four carefully screened young men were sealed in a space station simulator for 90 days and administered a tracking test battery. The battery included a clinical test (Critical Instability Task) designed to measure a subject's dynamic time delay, and a more conventional steady tracking task, during which dynamic response (describing functions) and performance measures were obtained. Good correlation was noted between the clinical critical instability scores and more detailed tracking parameters such as dynamic time delay and gain-crossover frequency. The levels of each parameter span the range observed with professional pilots and astronaut candidates tested previously. The chamber environment caused no significant decrement on the average crewman's dynamic response behavior, and the subjects continued to improve slightly in their tracking skills during the 90-day confinement period.

Allen, R. W.↗
NASA NTRS1973

Apollo 17 heat flow and convection experiments: Final data analyses results

A group of experiments called the Apollo 17 heat flow and convection (HFC) experiments was conducted, aboard the Apollo 17 spacecraft while in translunar coast on the way to the moon. These experiments together with the HFC experiments flown on Apollo 14 demonstrated and provided data on two types of low-g natural convection: cellular, surface tension-driven convection and convection in confined fluids caused by spacecraft and astronaut movements. Observed convection onset times show that surface tension-driven convection occurs at lower temperature gradients in low-g than in one-g environments. Data on heat flow in confined fluids show that spacecraft and astronaut movements can cause significant degrees of convection.

Bannister, T. C.↗
NASA NTRS1973

A satellite measurement of cosmic-ray abundances and spectra in the charge range 2 less than or equal to 7 less than or equal to 10

The composition of the nuclear component of the cosmic radiation was studied to yield information concerning the source, propagation, and confinement of cosmic rays within the galaxy. The first comprehensive satellite measurement is presented of cosmic-ray composition and spectra in the charge range 2 equal to or less than Z equal to or less than 10 using the geomagnetic field as a rigidity analyzer through the entire range of vertical cutoffs. The results indicate that the spectra of all the elements in the observed range are similar, and thus that various ratios of elemental abundances are nearly independent of rigidity over the range 2 equal to or less than P equal to or less than 15 GV. Calculations of the propagation of cosmic rays through the interstellar and interplanetary media predict that there should be a variation with rigidity of ratios of various elements, because of the charge-dependent effects of ionization of the interstellar gas by the cosmic rays. The absence of this variation can be explained by assuming a rigidity-dependent confinement of the cosmic rays in the galaxy.

Brown, J. W.↗
NASA NTRS1972

Elastic properties of Apollo 14 and 15 rocks.

Ultrasonic P- and S-wave velocities of lunar samples 14310,72 and 15418,43 and P-wave velocities of sample 15015,18 were measured at room temperature to 5 kb confining pressure. The velocities of both igneous and breccia samples increased sharply over this pressure range. At low confining pressures, the shape of velocity-pressure curves of rocks is determined by the distribution function of crack aspect ratios. We suggest that analogue studies on terrestrial rocks having a wide assortment of crack parameters may be used to infer the nature of cracks in lunar rocks.

Todd, T.↗
NASA NTRS1975

Straight-line IC removal tool

Tool operates by applying force perpendicularly to socket plane. Tool can be operated in cramped or confined quarters and can effect integrated circuit removal without damage. It may also be useful to hold nut or bolt in confined space while tightening, when it is not possible to use conventional tool.

Marzek, R. A.↗
NASA NTRS1973

Crew microbiology (DTO 71-19)

States of microbial imbalance as a result of human altitude chamber confinement occurred, for the most part, only in those genera and species of bacteria, yeast, and fungi which are classified as transients and are not part of the true indigenous flora of the crewmembers. Inasmuch as no crew illness events occurred and only subtle changes in the indigenous flora were noted, it appears that confinement of 56-days in a Skylab simulated environment does not mediate toward shifts in bacterial populations which have obvious clinical significance.

Wooley, B. C.↗
NASA NTRS1971

Optimization of life support systems and their systems reliability

The identification, analysis, and optimization of life support systems and subsystems have been investigated. For each system or subsystem that has been considered, the procedure involves the establishment of a set of system equations (or mathematical model) based on theory and experimental evidences; the analysis and simulation of the model; the optimization of the operation, control, and reliability; analysis of sensitivity of the system based on the model; and, if possible, experimental verification of the theoretical and computational results. Research activities include: (1) modeling of air flow in a confined space; (2) review of several different gas-liquid contactors utilizing centrifugal force: (3) review of carbon dioxide reduction contactors in space vehicles and other enclosed structures: (4) application of modern optimal control theory to environmental control of confined spaces; (5) optimal control of class of nonlinear diffusional distributed parameter systems: (6) optimization of system reliability of life support systems and sub-systems: (7) modeling, simulation and optimal control of the human thermal system: and (8) analysis and optimization of the water-vapor eletrolysis cell.

Fan, L. T.↗
NASA NTRS1974

Spectroscopic results in helium from the NASA Lewis Bumpy Torus plasma

Spectroscopic measurements were carried out on the NASA Lewis Bumpy Torus experiment in which a steady state ion heating method based on the modified Penning discharge is applied in a bumpy torus confinement geometry. Electron temperatures in pure helium are measured from the ratio of spectral line intensities. Measured electron temperatures range from 10 to 100 eV. Relative electron densities are also measured over the range of operating conditions. Radial profiles of temperature and relative density are measured in the two basic modes of operation of the device called the low and high pressure modes. The electron temperatures are used to estimate particle confinement times based on a steady state particle balance.

Richardson, R. W.↗
NASA NTRS1974

Post-shock spikes: A new feature of proton and alpha enhancements associated with an interplanetary shock wave

Abrupt and prolonged enhancements in the intensities of 100 to approximately 2000 keV nucleon protons and alpha particles observed in interplanetary space are interpreted as particle populations confined between an interplanetary shock front and a magnetic field discontinuity. Prominent intensity spikes observed only below approximately 400 keV per charge for both protons and alpha particles several hours behind the shock front suggest that some fraction of the confined particles is accelerated by an energy per charge dependent process.

Gloeckler, G.↗
NASA NTRS1973

Compressional and shear wave velocities in granular materials to 2.5 kilobars

The velocities of seismic compressional waves and, for the first time, shear wave velocities in silica sand, volcanic ash, and basalt powder were determined under hydrostatic confining pressures to 2.5 kb. Simultaneously, the porosity of these materials was obtained as a function of confining pressure. The presented results have important implications for the self-compaction hypothesis that has been postulated to explain the lunar near-surface seismic velocity variation.

Talwani, P.↗