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NASA NTRS2009

When the Wheels Touch Earth and the Flight is Through, Pilots Find One Eye is Better Than Two?

This study investigated the impact of near to eye displays on both operational and visual performance by employing a human-in-the-loop simulation of straight-in ILS approaches while using a near to eye (NTE) display. The approaches were flown in simulated visual and instrument conditions while using either a biocular NTE or a monocular NTE display on either the dominant or non dominant eye. The pilot s flight performance, visual acuity, and ability to detect unsafe conditions on the runway were tested.

Valimont, Brian↗

NASA NTRS2009

Finding the First Galaxies

Astronomers study distant galaxies by taking long exposures in deep survey fields. They choose fields that are empty of known sources, so that they are statistically representative of the Universe as a whole. Astronomers can compare the distribution of the detected galaxies in brightness, color, morphology and redshift to theoretical models, in order to puzzle out the processes of galaxy evolution. In 2004, the Hubble Space Telescope was pointed at a small, deep-survey field in the southern constellation Fornax for more than 500 hours of exposure time. The resulting Hubble Ultra-Deep Field could see the faintest and most distant galaxies that the telescope is capable of viewing. These galaxies emitted their light less than 1 billion years after the Big Bang. From the Ultra Deep Field and other galaxy surveys, astronomers have built up a history of star formation in the universe. the peak occurred about7 billion years ago, about half of the age of the current universe, then the number of stars that were forming was about 15 time the rate today. Going backward in time to when the very first starts and galaxies formed, the average star-formation rate should drop to zero. but when looking at the most distant galaxies in the Ultra Deep field, the star formation rate is still higher than it is today. The faintest galaxies seen by Hubble are not the first galaxies that formed in the early universe. To detect these galaxies NASA is planning the James Webb Space Telescope for launch in 2013. Webb will have a 6.5-meter diameter primary mirror, much bigger than Hubble's 2.4-meter primary, and will be optimized for infrared observations to see the highly redshifted galaxies.

Gardner, Jonathan P.↗

NASA NTRS2009

Finding ExoEarths: The Problem of Exozodical Dust

Dust coming from asteroids and comets will strongly affect direct imaging and characterization of terrestrial planets in the Habitable Zones of nearby stars. Such dust in the Solar System is called the zodiacal dust. Higher levels of similar dust are seen around many nearby stars, confined in disks called debris disks. Future high-contrast images of an Earth-like exoplanet (or "exoEarth") will very likely be background-limited by light scattered of both local Solar System zodiacal dust and circumstellar dust in the extrasolar system (exozodiacal dust). Clumps in the exozodiacal dust, which are expected in planet-hosting systems,, may also be a source of confusion. Here we discuss the problems associated with direct observations of an Earth-like planet in the presence of unknown levels of exozodiacal dust. Basic formulae showing the effect of zodiacal and exozodiacal dust on exoEarth direct imaging will be presented, and performance estimates for some future mission concepts summarized. Current detection limits for debris dust and future prospects for sensitive exozodiacal dust observations will also be discussed. Finally, we highlight a few additional problems relating to exozodiacal dust that have yet to be solved.

Roberge, Aki↗

NASA NTRS2009

Kepler: NASA's First Mission Capable of Finding Earth-Size Planets

Kepler, a NASA Discovery mission, is a spaceborne telescope designed to search a nearby region of our galaxy for Earth-size planets orbiting in the habitable zone of stars like our sun. The habitable zone is that region around a start where the temperature permits water to be liquid on the surface of a planet. Liquid water is considered essential forth existence of life. Mission Phases: Six mission phases have been defined to describe the different periods of activity during Kepler's mission. These are: launch; commissioning; early science operations, science operations: and decommissioning

Borucki, William J.↗

NASA NTRS2010

Finding Interstellar Particle Impacts on Stardust Aluminium Foils: The Safe Handling, Imaging, and Analysis of Samples Containing Femtogram Residues

Impact ionisation detectors on a suite of spacecraft have shown the direction, velocity, flux and mass distribution of smaller ISP entering the Solar System. During the aphelion segments of the Stardust flight, a dedicated collector surface was oriented to intercept ISP of beta = 1, and returned to Earth in January 2006. In this paper we describe the probable appeareance and size of IS particle craters from initial results of experimental impacts and numerical simulation, explain how foils are being prepared and mounted for crater searching by automated acquisition of high magnification electron images (whilst avoiding contamination of the foils) and comment on appropriate analytical techniques for Preliminary Examination (PE).

Kearsley, A. T.↗

NASA NTRS2006

System Finds Horizontal Location of Center of Gravity

An instrumentation system rapidly and repeatedly determines the horizontal location of the center of gravity of a laboratory vehicle that slides horizontally on three air bearings (see Figure 1). Typically, knowledge of the horizontal center-of-mass location of such a vehicle is needed in order to balance the vehicle properly for an experiment and/or to assess the dynamic behavior of the vehicle. The system includes a load cell above each air bearing, electronic circuits that generate digital readings of the weight on each load cell, and a computer equipped with software that processes the readings. The total weight and, hence, the mass of the vehicle are computed from the sum of the load-cell weight readings. Then the horizontal position of the center of gravity is calculated straightforwardly as the weighted sum of the known position vectors of the air bearings, the contribution of each bearing being proportional to the weight on that bearing. In the initial application for which this system was devised, the center- of-mass calculation is particularly simple because the air bearings are located at corners of an equilateral triangle. However, the system is not restricted to this simple geometry. The system acquires and processes weight readings at a rate of 800 Hz for each load cell. The total weight and the horizontal location of the center of gravity are updated at a rate of 800/3 approx. equals 267 Hz. In a typical application, a technician would use the center-of-mass output of this instrumentation system as a guide to the manual placement of small weights on the vehicle to shift the center of gravity to a desired horizontal position. Usually, the desired horizontal position is that of the geometric center. Alternatively, this instrumentation system could be used to provide position feedback for a control system that would cause weights to be shifted automatically (see Figure 2) in an effort to keep the center of gravity at the geometric center.

Johnston, Albert S.↗

NASA NTRS2009

Smart Ultrasound Remote Guidance Experiment (SURGE) Preliminary Findings

To date, diagnostic quality ultrasound images were obtained aboard the International Space Station (ISS) using the ultrasound of the Human Research Facility (HRF) rack in the Laboratory module. Through the Advanced Diagnostic Ultrasound in Microgravity (ADUM) and the Braslet-M Occlusion Cuffs (BRASLET SDTO) studies, non-expert ultrasound operators aboard the ISS have performed cardiac, thoracic, abdominal, vascular, ocular, and musculoskeletal ultrasound assessments using remote guidance from ground-based ultrasound experts. With exploration class missions to the lunar and Martian surfaces on the horizon, crew medical officers will necessarily need to operate with greater autonomy given communication delays (round trip times of up to 5 seconds for the Moon and 90 minutes for Mars) and longer periods of communication blackouts (due to orbital constraints of communication assets). The SURGE project explored the feasibility and training requirements of having non-expert ultrasound operators perform autonomous ultrasound assessments in a simulated exploration mission outpost. The project aimed to identify experience, training, and human factors requirements for crew medical officers to perform autonomous ultrasonography. All of these aims pertained to the following risks from the NASA Bioastronautics Road Map: 1) Risk 18: Major Illness and Trauna; 2) Risk 20) Ambulatory Care; 3) Risk 22: Medical Informatics, Technologies, and Support Systems; and 4) Risk 23: Medical Skill Training and Maintenance.

Hurst, Victor↗

NASA NTRS2010

Preliminary Geological Findings on the BP-1 Simulant

The following is a summation of information and discussion between Doug Stoeser of the USGS and Doug Rickman of NASA in February and March, 2010 pertaining to the BP-1 simulant. The analytical results and the bulk of the text are from communications from Dr. Stoeser. The BP-1 simulant is made from Black Point Basalt Flow, San Francisco Volcanic Field, northern Arizona. There is an aggregate (road metal) quarry on the northern margin of the flow towards the west end that was used as a Desert Research and Technology Studies (Desert RATS) analog test site. Silty material from this site was also used in laboratory tests and found to have geotechnical properties similar to the LHT-2M and Chenobi regolith simulants and is being proposed as a possible simulant for geotechnical use. It currently has the designation of BP-1 (Black Point 1). Figure

Rickman, D. L.↗

NASA NTRS2010

Finding, Browsing and Getting Data Easily Using SPDF Web Services

The NASA GSFC Space Physics Data Facility (5PDF) provides heliophysics science-enabling information services for enhancing scientific research and enabling integration of these services into the Heliophysics Data Environment paradigm, via standards-based approach (SOAP) and Representational State Transfer (REST) web services in addition to web browser, FTP, and OPeNDAP interfaces. We describe these interfaces and the philosophies behind these web services, and show how to call them from various languages, such as IDL and Perl. We are working towards a "one simple line to call" philosophy extolled in the recent VxO discussions. Combining data from many instruments and missions enables broad research analysis and correlation and coordination with other experiments and missions.

Candey, R.↗

NASA NTRS2010

Preliminary Geological Findings on the BP-1 Simulant

A waste material from an aggregate producing quarry has been used to make an inexpensive lunar simulant called BP-1. The feedstock is the Black Point lava flow in northern Arizona. Although this is part of the San Francisco volcanic field, which is also the source of the JSC-1 series feedstock, BP-1 and JSC-1 are distinct. Chemically, the Black Point flow is an amygdaloidal nepheline-bearing basalt. The amygdules are filled with secondary minerals containing opaline silica, calcium carbonate, and ferric iron minerals. X-ray diffraction (XRD) detected approximately 3% quartz, which is in line with tests done by the Kennedy Space Center Industrial Hygiene Office. Users of this material should use appropriate protective equipment. XRD also showed the presence of significant halite and some bassanite. Both are interpreted to be evaporative residues due to recycling of wash water at the quarry. The size distribution of BP-1 may be superior to some other simulants for some applications.

Stoeser, D. B.↗

NASA NTRS2010

Three-Dimensional Computed Tomography as a Method for Finding Die Attach Voids in Diodes

NASA analyzes electrical, electronic, and electromechanical (EEE) parts used in space vehicles to understand failure modes of these components. The diode is an EEE part critical to NASA missions that can fail due to excessive voiding in the die attach. Metallography, one established method for studying the die attach, is a time-intensive, destructive, and equivocal process whereby mechanical grinding of the diodes is performed to reveal voiding in the die attach. Problems such as die attach pull-out tend to complicate results and can lead to erroneous conclusions. The objective of this study is to determine if three-dimensional computed tomography (3DCT), a nondestructive technique, is a viable alternative to metallography for detecting die attach voiding. The die attach voiding in two- dimensional planes created from 3DCT scans was compared to several physical cross sections of the same diode to determine if the 3DCT scan accurately recreates die attach volumetric variability

Brahm, E. N.↗

NASA NTRS2010

How NASA Expanded its Innovation Framework to Find New Solutions to Old Problems

A radio frequency engineer from rural New Hampshire contributed the best solution to a public challenge issued by NASA's Space Life Sciences Directorate. This is a clear example of what Aneesh Chopra, the US Federal Chief Technology Officer, describes as the notion that in our society, knowledge is widely dispersed. And if it s widely dispersed, how do we capture the insights from the American people?" Chopra later said, to a live audience at the 2010 Rethinking Government event: "A semi-retired radio frequency engineer was able to share his idea about how to solve this problem, and it so blew away other ideas that NASA said it exceeded their requirements! No complicated RFP, the need for lobbyists, some convoluted processes, etc. Just a smart person who was paid a modest fee for his insight."

Davis, Jeffrey R.↗

NASA NTRS2009

Shuttle Wing Leading Edge Root Cause NDE Team Findings and Implementation of Quantitative Flash Infrared Thermography

Comparison metrics can be established to reliably and repeatedly establish the health of the joggle region of the Orbiter Wing Leading Edge reinforced carbon carbon (RCC) panels. Using these metrics can greatly reduced the man hours needed to perform, wing leading edge scanning for service induced damage. These time savings have allowed for more thorough inspections to be preformed in the necessary areas with out affecting orbiter flow schedule. Using specialized local inspections allows for a larger margin of safety by allowing for more complete characterizations of panel defects. The presence of the t-seal during thermographic inspection can have adverse masking affects on ability properly characterize defects that exist in the joggle region of the RCC panels. This masking affect dictates the final specialized inspection should be preformed with the t-seal removed. Removal of the t-seal and use of the higher magnification optics has lead to the most effective and repeatable inspection method for characterizing and tracking defects in the wing leading edge. Through this study some inadequacies in the main health monitoring system for the orbiter wing leading edge have been identified and corrected. The use of metrics and local specialized inspection have lead to a greatly increased reliability and repeatable inspection of the shuttle wing leading edge.

Burke, Eric R.↗

NASA NTRS2011

Noble Gas Analysis in the Quest to Find "Regolithic" Howardites

The howardite meteorites consist of approximately 200 polymict breccias of eucrite (basaltic) and diogenite (orthopyroxenitic) material (collectively, the HED group) that originate from the asteroid belt. Infrared reflectance spectroscopy of asteroids and laboratory studies of HEDs have indicated that the asteroid 4-Vesta is the likely parent body, and the partially-demolished south pole may be the source region. Asteroid regolith formation processes may be responsible for a number of observed petrological features including impact melt clasts, reworked clasts and mosaisicm. We have identified such features in a study of 30 howardites and polymict eucrites, and developed a regolith grading scheme based on petrology. However, the true regolithic nature of the howardite suite is not well defined, and previous research has suggested correlations between Ni contents of 300 - 1200 micron / g, a minimal variation in Al2O3 content around 8-9 wt% and the presence of solar wind noble gases are key hallmarks of an ancient regolith on Vesta . Through combined petrological, compositional and noble gas research, we aim to better understand howardite petrological diversity, regolith formation processes on parent asteroids, and to establish what defines a truly "regolithic" howardite. Our research will play an integral part in the interpretation of data gathered by the Dawn mission. Here we report the preliminary results from our noble gas analyses of four howardites: LEW 85313, EET 99408, MET 96500 and PCA 02066. Bulk major element compositional data have been collected, further petrological data for the HED group are reported by our colleagues, whilst trace-element analyses are underway. Our work will investigate the extent of whether previously described Ni, Al2O3 and noble gas characteristics are in fact indicative of a "regolithic" howardite.

Cartwright, Julia A.↗

NASA NTRS2010

Finding a 24 Day Orbital Period for the X-Ray Binary 1A 1118-616

We report the first determination of the binary period and the orbital ephemeris of the Be X-ray binary containing the pulsar IA 1118-616 (35 years after the discovery of the source). The orbital period is found to be P(sub orb) = 24.0+/-0.4 days. The source was observed by RXTE during its last big X-ray outburst in January 2009, peaking at MJD 54845.4. This outburst was sampled by taking short observations every few days, covering an elapsed time comparable to the orbital period. Using the phase connection technique, pulse arrival time delays could be measured and an orbital solution determined. The data are consistent with a circular orbit, the time of 90 degrees longitude was found to be T,/2 = MJD 54845.37(10), coincident with the peak X-ray flux.

Staubert, R.↗

NASA NTRS2010

Finding Extremely Compact Sources Using the ASKAP VAST Survey

VLBI observations of intraday variable (IDV) quasars found in the MASIV (Micro-Arcsecond Scintillation-Induced Variability) 5 GHz VLA Survey of 500 flat-spectrum sources in the northern sky have shown that these sources are extremely compact, often unresolved, on milliarcsecond scales, and more core-dominated than their non-IDV counterparts. VAST: an ASKAP Survey for Variables and Slow Transients, proposes to observe 10,000 square degrees of southern sky daily for 2 years in the VAST-Wide survey component. This is expected to reveal of order 30,000 compact sources brighter than 10 mJy showing refractive interstellar scintillation (the cause of centimeter-wavelength IDV) at the survey frequency of about 1.4 GHz. Many of these sources may be suitable astrometric calibrators for VLBI at higher frequencies.

Bignall, Hayley E.↗

NASA NTRS2010

Finding the Missing Stratospheric Br(sub y): A Global Modeling Study of CHBr3 and CH2Br2

Recent in situ and satellite measurements suggest a contribution of ~5 pptv to stratospheric inorganic bromine from short-lived bromocarbons. We conduct a modeling study of the two most important short-lived bromocarbons, bromoform (CHBr3) and dibromomethane (CH2Br2), with the Goddard Earth Observing System Chemistry Climate Model (GEOS CCM) to account for this missing stratospheric bromine. We derive a "top-down" emission estimate of CHBr3 and CH2Br2 using airborne measurements in the Pacific and North American troposphere and lower stratosphere obtained during previous NASA aircraft campaigns. Our emission estimate suggests that to reproduce the observed concentrations in the free troposphere, a global oceanic emission of 425 Gg Br yr(exp -1) for CHBr3 and 57 Gg Br yr(exp -l) for CH2Br2 is needed, with 60% of emissions from open ocean and 40% from coastal regions. Although our simple emission scheme assumes no seasonal variations, the model reproduces the observed seasonal variations of the short-lived bromocarbons with high concentrations in winter and low concentrations in summer. This indicates that the seasonality of short-lived bromocarbons is largely due to seasonality in their chemical loss and transport. The inclusion of CHBr3 and CH2Br2 contributes ~5 pptv bromine throughout the stratosphere. Both the source gases and inorganic bromine produced from source gas degradation (Br~SLS) in the troposphere are transported into the stratosphere, and are equally important. Inorganic bromine accounts for half (2.5 pptv) of the bromine from the inclusion of CHBr3 and CHzBr2 near the tropical tropopause and its contribution rapidly increases to ~ 100% as altitude increases. More than 85% of the wet scavenging of Br(sub y)(sup VSLS) occurs in large-scale precipitation below 500 hPa. Our sensitivity study with wet scavenging in convective updrafts switched off suggests that Br(sub y)(sup SLS) in the stratosphere is not sensitive to convection. Convective scavenging only accounts for ~0.2 pptv (4%) difference in inorganic bromine delivered to the stratosphere.

Liang, Q.↗

NASA NTRS2011

A Parametric Testing Environment for Finding the Operational Envelopes of Simulated Guidance Algorithms

The ever-increasing size and complexity of aerospace systems often drive developers to validate using modeling and Monte Carlo simulations confined around expected points of operation in a hyper-dimensional parameter space. This paper describes an alternative that explores large regions of the parameter space with explicit coverage guarantees, searching for n parameter relations that characterize a system's performance envelope.

Parametric testing↗