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NASA NTRS2016

A Year in Space: Early Results and Lessons Learned from the First Year-Long Expedition Aboard the International Space Station

Two ISS crewmembers recently completed the first year-long orbital stay in two decades. International cooperation was central to the success of Mikhail Kornienko from Russia and Scott Kelly from the United States. Their expedition leveraged current mission experience and capitalized on recent advances in health monitoring technology. This unique effort began in 2012 when the program managers of the ISS partner nations adopted two separate goals: greater multilateral cooperation to increase efficiency of inflight research and a year-long expedition to gain familiarity with in-flight durations approaching that required for a Mars mission. These goals were unified when a set of bilateral Russian and American human research investigations was assigned to the year-long mission, augmented by additional investigations from Europe and Japan. For example, Kelly was assigned 18 investigations (twice the complement on standard six-month missions) including two joint U.S.-Russian studies, and two Russian and two Japanese studies. The core set of American investigations was a repetition of six studies Kelly had done on his previous six-month ISS mission, to allow a direct comparison of physiological and behavioral responses of the longer and shorter durations in this single individual. The remainder of his assignments plus those of Kornienko were drawn from currently active national investigations documenting human adaptation to long-duration spaceflight factors or effectiveness of countermeasures against known deleterious adaptations. The two joint U.S.-Russian investigations were the flagship biomedical studies of the year-long expedition. The "Fluid Shifts" study collocated American research equipment alongside a Russian operational stressor device to document the pattern and impacts of the headward fluid shift long known to occur in weightlessness, including its role in ocular changes recently observed in some astronauts. The "Field Test" study investigated the ability of the astronaut and cosmonaut to perform rudimentary tasks requiring sensorimotor coordination immediately after landing to define human capabilities soon after landing on Mars after an extended transit. Both investigations were highly successful in large part to the thorough integration of the implementation processes of the two partners. Kelly's assignment as the one-year crewmember also provided a serendipitous opportunity for the "Twins Study" comparing changes in his body at the genetic level with those occurring on Earth in his identical twin brother Mark Kelly. Data analysis from this expedition will commence in earnest after frozen in-flight samples are delivered to Earth in May aboard a commercial cargo spacecraft. Detailed results are expected in early 2017. Preliminary results and implementation improvements will be reviewed in this presentation.

Charles, J. B.↗

NASA NTRS2017

The Effects of Long-Duration Spaceflight on Training Retention and Transfer

Training our crew members for long duration, exploration-class missions will have to maximize long-term retention and transfer of the trained skills. The expected duration of the missions, our inability to predict all the possible tasks the crew will be called upon to perform, and the low training-to-mission time ratio require that the training be maximally effective such that the skills acquired during training will be retained and will be transferrable across a wide range of specific tasks that are different from the particular tasks used during training. However, to be able to design training that can achieve these ambitious goals, we must first understand the ways in which long-duration spaceflight affects training retention and transfer. Current theories of training retention and transfer are largely based on experimental studies conducted at university laboratories using undergraduate students as participants. Furthermore, all such studies have been conducted on Earth. We do not know how well the results of these studies predict the performance of crew members. More specifically, we do not know how well the results of these studies predict the performance of crew members in space and especially during long-duration missions. To address this gap in our knowledge, the current on-going study seeks to test the null hypothesis that performance of university undergraduate students on Earth on training retention and transfer tests do in fact predict accurately the performance of crew members during long-duration spaceflights. To test this hypothesis, the study employs a single 16-month long experimental protocol with 3 different participant groups: undergraduate university students, crew members on the ground, and crew members in space. Results from this study will be presented upon its completion. This poster presents results of study trials of the two tasks used in this study: a data entry task and a mapping task. By researching established training principles, by examining future needs, and by using current practices in spaceflight training as test beds, this research project is mitigating program risks and generating templates and requirements to meet future training needs.

ISS↗

NASA NTRS2018

The Effects of Long-Duration Spaceflight on Training Retention and Transfer

training↗

NASA NTRSDate not supplied

Bionutrients-1: Utilizing Genomics and Transcriptomics to Assess the Reliability of Microorganisms for In Situ Nutrient Production on Long Duration Missions

The resupply of current long-duration crewed missions to the ISS relies on ground-launched supplies. As NASA looks toward Mars, ground-based resupply will no longer be an option. Critical nutrients, including vitamin C, vitamin K, folate, and thiamin, degrade during long-term storage, and regular consumption of these nutrients is essential for astronaut health. Another challenge of current food systems is the difficulty of consuming sufficient calories when subsisting on the limited flavors of freeze-dried food, which can lead to weight loss. The inclusion of microorganism-based food systems could alleviate both concerns. For example, the fermentation of rehydrated milk into yogurt with microorganisms genetically incorporating genes to produce critical vitamins would allow for both in situ production of nutrients and a fresh food product with additional flavor profiles. In comparison to plant food production, microorganisms require less flight infrastructure. The BioNutrients-1 mission is demonstrating viability of microbial fermentation food production in microgravity and testing the reliability of this approach for long-duration missions lacking resupply. While the BioNutrients-1 mission includes the collection of multiple phenotypic measurements, this status update will focus on the processing of samples for genomics and transcriptomics analyses as well as the planned analysis pipelines. First, the BioNutrients-1 mission seeks to identify microorganisms capable of surviving long-duration storage at ambient temperatures while maintaining genetic fidelity. To achieve this, nine commonly employed microbial species were stored at ambient temperatures in Stasis Packs on the ISS for five years. The viability and mutation rates will be measured at multiple time points for both flown and ground control samples. From an omics perspective, the changes in the bulk rates of point mutations and genetic rearrangements across the Stasis Pack species during the five years of storage will be determined, providing valuable insights into the potential of these microorganisms for long-duration space missions. Second, the BioNutrients-1 mission is characterizing the impact of microgravity on fermentation. Two strains of the yeast Saccharomyces cerevisiae, each encoding antioxidants (β-carotene or zeaxanthin) were flown to ISS for storage and fermentation within simplified bioreactors (Production Packs). The impact of microgravity on the expression of the antioxidant production genes and general metabolic genes will be determined using RNA sequencing. Ultimately, the transcriptome data will be compared to phenotypic measurements, such as the antioxidant yield, end-state biomass, and the production of EtOH, to determine the impacts of microgravity and long-term storage on microbial fermentation. The findings from this research will be instrumental in understanding the challenges and opportunities of microorganism-based food systems in space missions.

BioNutrients↗

NASA NTRS1995

A high-resolution OGCM simulation of the Tropical Pacific Ocean during the 1985-1994 TOGA period. Part I: Long equatorial waves

A high resolution oceanic general circulation model of the three topical oceans is used to investigate long equatorial wave activity in the Pacific Ocean during the 1985-1994 TOGA period. Zonal wind stress forcing and simulated dynamic height are interpreted using techniques previously applied to data. Kelvin and first Rossby waves are observed propagating during all the period. A seasonal cycle and interannual anomalies are computed for each long equatorial wave. The east Pacific basin is mainly dominated by seasonal cycle variations while strong interannual anomalies are observed west of the dateline. Long wave interannual anomalies are then compared to wave coefficients simulated by a simple wind-forced model. Our results outline the major role played by wind forcing on interannual time scales in generating long equatorial waves. However, near both eastern and western boundaries, some differences can be attributed to long wave reflections. A comparison to wave coefficients calculated from GEOSAT sea-level data gives some insight of the model behavior.

Long Equatorial Waves↗

NASA NTRS2019

Demonstrating Next Generation High-Altitude, Long Endurance Aircraft for Earth Science

This paper will address NASA activities to monitor and study Earth processes from long-duration unmanned aircraft systems (UAS). NASA is currently supporting both large and small UAS development and demonstration. In a follow-on to previous work, NASA Armstrong Flight Research Center is hosting test flights of a large AeroVironment solar-powered aircraft, while NASA Ames Research Center is supporting the demonstration of a light-weight solar powered aircraft by Swift Engineering. Both are designed for long duration, multi-day flight. NASA Earth Science and Aeronautics researchers have been involved in the development and use of High Altitude Long Endurance (HALE) UAS since the 1990's. The NASA Environmental Research Aircraft Sensor and Technology Program (ERAST) demonstrated the promise of HALE aircraft for providing observations while also proving the importance of triple-redundant avionics to improve system reliability for large unmanned aircraft. Early efforts to develop an operational HALE capability for earth observations languished for nearly two decades owing to insufficient solar panel efficiency, battery power density, and light-weight, yet strong, materials. During this time NASA researchers focused on using the Global Hawk to demonstrate the utility of providing diurnal measurements over severe storms (i.e. HS3) and to track stratospheric water vapor transport (ATTREX). Recent significant commercial investments are now leading to the realization of a long-held goal of week- to month-long sustained observations and measurements from the stratosphere. In addition to a historical review of NASA use and interest in HALE aircraft, this paper will present current concepts for exploiting current and planned HALE aircraft capabilities including in situ characterization of atmospheric composition and dynamics as well as imagery collection and internet connectivity. NASA researchers anticipate HALE will also provide a useful means to test smallsat instruments and components. Observations from HALE-based instruments might also provide useful gap-filler observations to flagship satellite missions where the repeat time doesn't allow for measurements of quickly changing phenomenon. HALE will likely also provide measurements and communications relay to facilitate other aircraft in multi-aircraft campaigns. We will also report on progress towards a NASA-supported flight tests solar electric vehicles planned for 2019. One is the Swift Engineering UAS designed to carry 7kg (15lbs) for 30 days at 20km altitude. The other is the AeroVironment Hawk 30, also designed for multi-day flight.

high-altitude↗

NASA NTRSDate not supplied

Sleep during layovers of different lengths after long-haul flying across multiple time zones in different geographic directions

Introduction: Long-haul pilots experience high levels of fatigue and circadian disruption due to long work hours and trans-meridian travel. The aim of this study was to characterize sleep timing and duration during layovers of different lengths after crossing multiple time zones. Methods: All pilots flying long-haul operations from a single airline were eligible to participate. While following their normal work schedule within airline operations, pilots collected data for ~2 weeks including at least two long-haul rotations, with rest days and layovers. Participants wore an Actiwach (Phillips Respironics) throughout the entire study period and completed a sleep diary (at bedtime and upon waking up). Based on the data, we categorized layovers as follows: layover type 1: 34 h after crossing five time zones in westward direction; layover type 2: of 34 h, no time zone change; layover type 3: 55 h after crossing six time zones in eastward direction. Each flight left the home base at the same time of day (23:00) and the flight duration was between 10.5 and 12 hrs. We calculated descriptive statistics for each category. Results. Forty-four long-haul pilots participated in the study (5 female; mean age 44.25 ± 10.06 yrs; mean flight hours 9834.3 ± 5334.1 hrs). We found that for layover type 1, the mean sleep duration (h) per 24 h was 6.90 (±1.04), mean sleep efficiency (%) was 81.08 (±10.89) and mean Wake After Sleep Onset (WASO, min) was 33.23 (±20.42); for layover type 2, the mean sleep duration (h) per 24 h was 6.91 (±1.06), mean sleep efficiency (%) was 81.71 (±6.80), and mean WASO (min) was 30.10 (±11.00); for layover type 3, the mean sleep duration (h) was 7.07 (±1.32), mean sleep efficiency (%) was 83.93 (±6.04), and mean WAS (min) was 36.94 (±17.95). Conclusion: Our preliminary analyses showed that sleep duration and sleep efficiency were similar for the layovers of same length regardless time zone change. Additional analyses will be conducted to investigate sleep on additional layovers of different lengths and the effects of sleep obtained during layover on the performance and alertness on the return flights.

long-haul↗

NASA NTRS1974

Management and design of long-life systems; Proceedings of the Symposium, Denver, Colo., April 24-26, 1973

The long life of Pioneer interplanetary spacecraft is considered along with a general accelerated methodology for long-life mechanical components, dependable long-lived household appliances, and the design and development philosophy to achieve reliability and long life in large turbine generators. Other topics discussed include an integrated management approach to long life in space, artificial heart reliability factors, and architectural concepts and redundancy techniques in fault-tolerant computers. Individual items are announced in this issue.

Schurmeier, H. M.↗

NASA NTRS1975

Attempt at correlating Italian long lineaments from LANDSAT-1 satellite images with some geological phenomena. Possible use in geothermal energy research

By utilizing the images from the LANDSAT-1, in the spectral band 0.8-1.1 microns (near infrared), a photomosaic was obtained of Italian territory. From this mosaic the field of long lineaments was drawn, corresponding to fractures of the earth crust more than 100 km long. The relationship between lineaments, hot springs, volcanic areas, and earthquake epicenters is verified. There is a clear connection between long lineaments and hot springs: 78% of the springs are located on one or more lineaments, and the existence of hot lineaments was observed. A slightly weaker, but still significant, connection exists between the Pliocene-Quaternary volcanic areas and long lineaments. The relationship between earthquakes and long lineaments can only be verified in some cases. The lineaments which can be related to earthquakes have little or no connection with the other phenomena.

Barbier, E.↗

NASA NTRS1978

Modulation of short waves by long waves

Wave-tank experiments were performed to investigate the cyclic short-wave energy changes, related in phase to an underlying long wave, which occur during active generation of the short-wave field by wind. Measurements of time series of the short-wave slope were made by a laser-optical system, where the basic long-wave parameters were controlled and wind speeds were accurately reproducible. The short-wave slope variances were found to exhibit cyclic variations that are related to the phase of the long wave. The variations result from two combined effects: (1) the short wave frequency is varied by the long-wave orbital velocity; (2) the energy of the short waves is modulated by the actions of aerodynamic and hydrodynamic couplings that operate on the short waves in a manner related to the long-wave phase.

Reece, A. M., Jr.↗

NASA NTRS1982

Investigation of the interference effects of mixed flow long duct nacelles on a DC-10 wing

Wind tunnel test results utilizing a 4.7 percent scale semispan model in the 11 foot transonic wind tunnel are presented. A low drag long duct nacelle installation for the DC-10 jet transport was developed. A long duct nacelle representative of a CF6-50 mixed flow configuration was investigated on the DC-10-30. The results showed that the long duct nacelle installation located in the same position as the current short duct nacelle and with the current production symmetrical pylon is a relatively low risk installation for the DC-10 aircraft. Tuft observations and analytical boundary layer analysis confirmed that the flow on the nacelle afterbody was attached. A small pylon fairing was evaluated and found to reduce channel peak suction pressures, which resulted in a small drag improvement. The test also confirmed that the optimum nacelle incidence angle is the same as for the short duct nacelle, thus the same engine mount as for the production short duct nacelle can be used for the long duct nacelle installation. Comparison of the inboard wing pylon nacelle channel pressure distributions, with flow through and powered long duct nacelles showed that the power effects did not change the flow mechanism; hence, power effects can be considered negligible.

Patel, S. P.↗

NASA NTRS1991

Stirling engine: Available tools for long-life assessment

A review is presented for the durability approaches applicable to long-time life assessment of Stirling engine hot-section components. The crucial elements are experimental techniques for generating long-time materials property data (both monotonic and cyclic flow and failure properties); analytic representations of slow strain rate material stress-strain response characteristics (monotonic and cyclic constitutive relations) at high temperatures and low stresses and strains; analytic creep-fatigue-environmental interaction life prediction methods applicable to long lifetimes at high temperatures and small stresses and strains; and experimental verification of life predictions. Long-lifetime design criteria for materials of interest are woefully lacking. Designing against failures due to creep, creep-rupture, fatigue, environmental attack, and creep-fatigue-environmental interaction will require considerable extrapolation. Viscoplastic constitutive models and time-temperature parameters will have to be calibrated for the hot-section materials of interest. Analysis combined with limited verification testing in a short-time regime will be required to build confidence in long-lifetime durability models.

Halford, Gary R.↗

NASA NTRS1991

Stirling engine - Available tools for long-life assessment

A review is presented for the durability approaches applicable to long-time life assessment of Stirling engine hot-section components. The crucial elements are experimental techniques for generating long-time materials property data (both monotonic and cyclic flow and failure properties); analytic representations of slow strain rate material stress-strain response characteristics (monotonic and cyclic constitutive relations) at high temperatures and low stresses and strains; analytic creep-fatigue-environmental interaction life prediction methods applicable to long lifetimes at high temperatures and small stresses and strains; and experimental verification of life predictions. Long-lifetime design criteria for materials of interest are woefully lacking. Designing against failures due to creep, creep-rupture, fatigue, environmental attack, and creep-failure-environmental interaction will require considerable extrapolation. Viscoplastic constitutive models and time-temperature parameters will have to be calibrated for the hot-section materials of interest. Analysis combined with limited verification testing in a short-time regime will be required to build confidence in long-lifetime durability models.

Halford, Gary R.↗

NASA NTRS1992

Potential of long-baseline infrared interferometry for narrow-angle astrometry

Narrow-angle astrometry has many astrophysical applications, from the measurement of parallaxes to the search for planets around nearby stars. Ground-based long-focus telescopes with photoelectric detectors have achieved accuracies of about 2-3 milliarcsec in 1 h. This accuracy is limited primarily by the atmosphere, and is consistent with models of atmospheric turbulence. However, applying these turbulence models to observations with long-baseline interferometers yields astrometric errors that are far smaller than can be achieved with long-focus telescopes. The predictions for the ultimate accuracy of ground-based narrow-angle astrometry using long-baseline IR (2.2 micron) stellar interferometers are very promising. With the excellent seeing at a high altitude site like Mauna Kea, the atmospheric limit for a 1 h astrometric measurement is expected to be of the order of 10 microarcsec for 1 h of integration. This two-order-of-magnitude improvement over conventional measurements is due to two effects. One is that a long-baseline IR interferometer can find useful reference stars very near an arbitrary target star, so that the atmospherically-induced motions of both stars are highly correlated. The second is that the baseline length can be much larger than the separation of the stellar beams in the turbulent atmosphere, resulting in a reduction in astrometric error with increasing baseline length.

Shao, M.↗

NASA NTRS1994

Possibility to sound the atmospheric ozone by a radiosonde equipped with two temperature sensors, sensitive and non-sensitive to the long wave radiation

The sensitiveness of white coated thermistor sensors and non-sensitiveness of the gold coated over white thermistor sensors (which have been manufactured by a vacuum evaporation process) to long wave radiation were ascertained by some simple experiments in-room and also by analyses of some results of experimental soundings. From results of analyses on the temperature discrepancies caused by long wave radiation, the possibility to sound the atmospheric ozone partial pressure by a radiosonde equipped with two kinds of sensors, sensitive and non-sensitive to the long wave radiation was suggested, and the test results of the newly developed software for the deduction of ozone partial pressure in upper layers was also shown. However, it was found that the following is the necessary condition to realize the purpose. The sounding should be made by a radiosonde equipped with three sensors, instead of two, one being non-sensitive to the long wave radiation perfectly, and the other two also non-sensitive partially to the downward one, with two different angles of exposure upward. It is essential for the realization of the purpose to get two different values of temperature discrepancies simultaneously observed by the three sensors mentioned above and to avoid the troublesome effects of the upward long wave radiation.

Kitaoka, T.↗

NASA NTRS1997

SBUV/2 Long-Term Measurements of Solar Spectral Variability

The NOAA-11 SBUV/2 spectral solar data have been corrected for long-term instrument changes to produce a 5.5 year data record during solar cycle 22 (December 1988 - October 1994). Residual drifts in the data at long wavelengths are +/- 1% or less. At 200-205 nm, where solar variations drive stratospheric photochemistry, these data indicate long-term solar changes of 5-7% from the maximum of Cycle 22 in April 1991 through the end of the NOAA-11 data record. Comparisons of NOAA-11 data with UARS SUSIM and SOLSTICE for the period October 1991 - October 1994, when all 3 instruments were operating simultaneously, show that the observed long-term variations in 200-205 nm irradiance agree to within 2%. This result is consistent with predictions from the Mg-2 proxy index. The SBUV/2 instruments represent a valuable resource for long-term solar UV activity studies because of their overlapping data records. In addition to the NOAA-11 data presented here, the NOAA-9 SBUV/2 instrument began taking data in March 1985 and is still operating, providing a complete record of Cycle 22 behavior from a single instrument. Three additional SBUV/2 instruments are scheduled to be launched between 1997 and 2003, which should permit full coverage of solar cycle 23.

DeLand, Matthew T.↗

NASA NTRS1997

Long-Period Comets and the Oort Cloud

The long-period comets pose a unique problem for the impact hazard problem. Because of their very long orbital] periods and generally large distances from the Sun, they cannot be surveyed and catalogued in the same manner as the near-Earth asteroids and short-period comets. They appear at random, uniformly distributed on the celestial sphere. Current technologies can detect long-period comets at distances of approx. 5 AU, giving somewhat less than a one year warning time for potential Earth impactors. The mean impact probability for a long-period comet crossing the Earth's orbit is 2.2 to 2.5 x 10(exp -9) per perihelion passage. The mean impact velocity is approximately 52 km sec-1 but the most probable impact energy is characterized by a velocity of 56 to 58 km/sec. The estimated current impact rate for cometary nuclei large enough to create 10 km diameter (or larger) craters on the Earth is between 5 x 10(exp -7) and 2.8 x 10(exp -6) per year, with a bed estimated value of 1.0 x 10(exp -6) per year. Nuclei large enough to initiate global climatic disturbances strike the Earth on average every 16 Myr. The impact frequency may be increased substantially for brief periods of time during cometary showers, initiated by major perturbations of the Oort cloud. Improved technologies are needed to detect approaching long-period comets at large heliocentric distances so as to increase the warning time for potential impactors.

Weissman, Paul R.↗

NASA NTRS1999

Demonstration of a Low Cost Cryocooler on a Long Duration Balloon Mission

NASA/GSFC has been evaluating the use of low cost Stirling cycle cryocoolers for aerospace applications since 1994. These include the M77B and M77C cryocoolers built by Sunpower Corporation. To date NASA has tested eight M77B and two M77C cryocoolers, with 8 additional M77C units now under construction. The intent of this work is to determine the flight worthiness of these cryocoolers. The Sunpower M77 coolers are candidate for use on the Ultra Long Duration Balloons presently under development by NASA. The flight on the Long Duration Balloon (LDB) in July 1998 represented an opportunity to test the cryocooler in the high altitude balloon environment in order to gain experience to prepare for possible opportunities on the Ultra Long Duration Balloon (ULDB) missions. The Long Duration Balloon is typically a 10 to 15 day mission. Typical ULDB missions might be as long as 100 days or more, and it is this duration which now forces many science groups to consider the use of cryocoolers in place of stored cryogens. This paper will present the basic design of the cryocooler experiment, and data acquired during the flight. The paper will also include a general perspective on the use of cryocoolers on future ULDB flights.

James, Edward F.↗