LROC Advances in Lunar Science

NASA Astrophysics Data System (ADS)

Robinson, M. S.

2012-12-01

Since entering orbit in 2009 the Lunar Reconnaissance Orbiter Camera (LROC) has acquired over 700,000 Wide Angle Camera (WAC) and Narrow Angle Camera (NAC) images of the Moon. This new image collection is fueling research into the origin and evolution of the Moon. NAC images revealed a volcanic complex 35 x 25 km (60N, 100E), between Compton and Belkovich craters (CB). The CB terrain sports volcanic domes and irregular depressed areas (caldera-like collapses). The volcanic complex corresponds to an area of high-silica content (Diviner) and high Th (Lunar Prospector). A low density of impact craters on the CB complex indicates a relatively young age. The LROC team mapped over 150 volcanic domes and 90 volcanic cones in the Marius Hills (MH), many of which were not previously identified. Morphology and compositional estimates (Diviner) indicate that MH domes are silica poor, and are products of low-effusion mare lavas. Impact melt deposits are observed with Copernican impact craters (>10 km) on exterior ejecta, the rim, inner wall, and crater floors. Preserved impact melt flow deposits are observed around small craters (25 km diam.), and estimated melt volumes exceed predictions. At these diameters the amount of melt predicted is small, and melt that is produced is expected to be ejected from the crater. However, we observe well-defined impact melt deposits on the floor of highland craters down to 200 m diameter. A globally distributed population of previously undetected contractional structures were discovered. Their crisp appearance and associated impact crater populations show that they are young landforms (<1 Ga). NAC images also revealed small extensional troughs. Crosscutting relations with small-diameter craters and depths as shallow as 1 m indicate ages <50 Ma. These features place bounds on the amount of global radial contraction and the level of compressional stress in the crust. WAC temporal coverage of the poles allowed quantification of highly illuminated regions, including one site that remains lit for 94% of a year (longest eclipse period of 43 hours). Targeted NAC images provide higher resolution characterization of key sites with permanent shadow and extended illumination. Repeat WAC coverage provides an unparalleled photometric dataset allowing spatially resolved solutions (currently 1 degree) to Hapke's photometric equation - data invaluable for photometric normalization and interpreting physical properties of the regolith. The WAC color also provides the means to solve for titanium, and distinguish subtle age differences within Copernican aged materials. The longevity of the LRO mission allows follow up NAC and WAC observations of previously known and newly discovered targets over a range of illumination and viewing geometries. Of particular merit is the acquisition of NAC stereo pairs and oblique sequences. With the extended SMD phase, the LROC team is working towards imaging the whole Moon with pixel scales of 50 to 200 cm.

Lunar geodesy and cartography: a new era

NASA Astrophysics Data System (ADS)

Duxbury, Thomas; Smith, David; Robinson, Mark; Zuber, Maria T.; Neumann, Gregory; Danton, Jacob; Oberst, Juergen; Archinal, Brent; Glaeser, Philipp

The Lunar Reconnaissance Orbiter (LRO) ushers in a new era in precision lunar geodesy and cartography. LRO was launched in June, 2009, completed its Commissioning Phase in Septem-ber 2009 and is now in its Primary Mission Phase on its way to collecting high precision, global topographic and imaging data. Aboard LRO are the Lunar Orbiter Laser Altimeter (LOLA -Smith, et al., 2009) and the Lunar Reconnaissance Orbiter Camera (LROC -Robinson, et al., ). LOLA is a derivative of the successful MOLA at Mars that produced the global reference surface being used for all precision cartographic products. LOLA produces 5 altimetry spots having footprints of 5 m at a frequency of 28 Hz, significantly bettering MOLA that produced 1 spot having a footprint of 150 m at a frequency of 10 Hz. LROC has twin narrow angle cameras having pixel resolutions of 0.5 meters from a 50 km orbit and a wide-angle camera having a pixel resolution of 75 m and in up to 7 color bands. One of the two NACs looks to the right of nadir and the other looks to the left with a few hundred pixel overlap in the nadir direction. LOLA is mounted on the LRO spacecraft to look nadir, in the overlap region of the NACs. The LRO spacecraft has the ability to look nadir and build up global coverage as well as looking off-nadir to provide stereo coverage and fill in data gaps. The LROC wide-angle camera builds up global stereo coverage naturally from its large field-of-view overlap from orbit to orbit during nadir viewing. To date, the LROC WAC has already produced global stereo coverage of the lunar surface. This report focuses on the registration of LOLA altimetry to the LROC NAC images. LOLA has a dynamic range of tens of km while producing elevation data at sub-meter precision. LOLA also has good return in off-nadir attitudes. Over the LRO mission, multiple LOLA tracks will be in each of the NAC images at the lunar equator and even more tracks in the NAC images nearer the poles. The registration of LOLA altimetry to NAC images is aided by the 5 spots showing regional and local slopes, along and cross-track, that are easily correlated visually to features within the images. Once can precisely register each of the 5 LOLA spots to specific pixels in LROC images of distinct features such as craters and boulders. This can be performed routinely for features at the 100 m level and larger. However, even features at the several m level can also be registered if a single LOLA spots probes the depth of a small crater while the other 4 spots are on the surrounding surface or one spot returns from the top of a small boulder seen by NAC. The automatic registration of LOLA tracks with NAC stereo digital terrain models should provide for even higher accuracy. Also the LOLA pulse spread of the returned signal, which is sensitive to slopes and roughness, is an additional source of information to help match the LOLA tracks to the images As the global coverage builds, LOLA will provide absolute coordinates in latitude, longitude and radius of surface features with accuracy at the meter level or better. The NAC images will then be reg-istered to the LOLA reference surface in the production of precision, controlled photomosaics, having spatial resolutions as good as 0.5 m/pixel. For hundreds of strategic sites viewed in stereo, even higher precision and more complete surface coverage is possible for the produc-tion of digital terrain models and mosaics. LRO, with LOLA and LROC, will improve the relative and absolute accuracy of geodesy and cartography by orders of magnitude, ushering in a new era for lunar geodesy and cartography. Robinson, M., et al., Space Sci. Rev., DOI 10.1007/s11214-010-9634-2, Date: 2010-02-23, in press. Smith, D., et al., Space Sci. Rev., DOI 10.1007/s11214-009-9512-y, published online 16 May 2009.

Sharpening Ejecta Patterns: Investigating Spectral Fidelity After Controlled Intensity-Hue-Saturation Image Fusion of LROC Images of Fresh Craters

NASA Astrophysics Data System (ADS)

Awumah, A.; Mahanti, P.; Robinson, M. S.

2017-12-01

Image fusion is often used in Earth-based remote sensing applications to merge spatial details from a high-resolution panchromatic (Pan) image with the color information from a lower-resolution multi-spectral (MS) image, resulting in a high-resolution multi-spectral image (HRMS). Previously, the performance of six well-known image fusion methods were compared using Lunar Reconnaissance Orbiter Camera (LROC) Narrow Angle Camera (NAC) and Wide Angle Camera (WAC) images (1). Results showed the Intensity-Hue-Saturation (IHS) method provided the best spatial performance, but deteriorated the spectral content. In general, there was a trade-off between spatial enhancement and spectral fidelity from the fusion process; the more spatial details from the Pan fused with the MS image, the more spectrally distorted the final HRMS. In this work, we control the amount of spatial details fused (from the LROC NAC images to WAC images) using a controlled IHS method (2), to investigate the spatial variation in spectral distortion on fresh crater ejecta. In the controlled IHS method (2), the percentage of the Pan component merged with the MS is varied. The percent of spatial detail from the Pan used is determined by a variable whose value may be varied between 1 (no Pan utilized) to infinity (entire Pan utilized). An HRMS color composite image (red=415nm, green=321/415nm, blue=321/360nm (3)) was used to assess performance (via visual inspection and metric-based evaluations) at each tested value of the control parameter (1 to 10—after which spectral distortion saturates—in 0.01 increments) within three regions: crater interiors, ejecta blankets, and the background material surrounding the craters. Increasing the control parameter introduced increased spatial sharpness and spectral distortion in all regions, but to varying degrees. Crater interiors suffered the most color distortion, while ejecta experienced less color distortion. The controlled IHS method is therefore desirable for resolution-enhancement of fresh crater ejecta; larger values of the control parameter may be used to sharpen MS images of ejecta patterns but with less impact to color distortion than in the uncontrolled IHS fusion process. References: (1) Prasun et. al (2016) ISPRS. (2) Choi, Myungjin (2006) IEEE. (3) Denevi et. al (2014) JGR.

Cartography of the Luna-21 landing site and Lunokhod-2 traverse area based on Lunar Reconnaissance Orbiter Camera images and surface archive TV-panoramas

NASA Astrophysics Data System (ADS)

Karachevtseva, I. P.; Kozlova, N. A.; Kokhanov, A. A.; Zubarev, A. E.; Nadezhdina, I. E.; Patratiy, V. D.; Konopikhin, A. A.; Basilevsky, A. T.; Abdrakhimov, A. M.; Oberst, J.; Haase, I.; Jolliff, B. L.; Plescia, J. B.; Robinson, M. S.

2017-02-01

The Lunar Reconnaissance Orbiter Camera (LROC) system consists of a Wide Angle Camera (WAC) and Narrow Angle Camera (NAC). NAC images (∼0.5 to 1.7 m/pixel) reveal details of the Luna-21 landing site and Lunokhod-2 traverse area. We derived a Digital Elevation Model (DEM) and an orthomosaic for the study region using photogrammetric stereo processing techniques with NAC images. The DEM and mosaic allowed us to analyze the topography and morphology of the landing site area and to map the Lunokhod-2 rover route. The total range of topographic elevation along the traverse was found to be less than 144 m; and the rover encountered slopes of up to 20°. With the orthomosaic tied to the lunar reference frame, we derived coordinates of the Lunokhod-2 landing module and overnight stop points. We identified the exact rover route by following its tracks and determined its total length as 39.16 km, more than was estimated during the mission (37 km), which until recently was a distance record for planetary robotic rovers held for more than 40 years.

LROC Observations of Geologic Features in the Marius Hills

NASA Astrophysics Data System (ADS)

Lawrence, S.; Stopar, J. D.; Hawke, R. B.; Denevi, B. W.; Robinson, M. S.; Giguere, T.; Jolliff, B. L.

2009-12-01

Lunar volcanic cones, domes, and their associated geologic features are important objects of study for the LROC science team because they represent possible volcanic endmembers that may yield important insights into the history of lunar volcanism and are potential sources of lunar resources. Several hundred domes, cones, and associated volcanic features are currently targeted for high-resolution LROC Narrow Angle Camera [NAC] imagery[1]. The Marius Hills, located in Oceanus Procellarum (centered at ~13.4°N, -55.4°W), represent the largest concentration of these volcanic features on the Moon including sinuous rilles, volcanic cones, domes, and depressions [e.g., 2-7]. The Marius region is thus a high priority for future human lunar exploration, as signified by its inclusion in the Project Constellation list of notional future human lunar exploration sites [8], and will be an intense focus of interest for LROC science investigations. Previous studies of the Marius Hills have utilized telescopic, Lunar Orbiter, Apollo, and Clementine imagery to study the morphology and composition of the volcanic features in the region. Complementary LROC studies of the Marius region will focus on high-resolution NAC images of specific features for studies of morphology (including flow fronts, dome/cone structure, and possible layering) and topography (using stereo imagery). Preliminary studies of the new high-resolution images of the Marius Hills region reveal small-scale features in the sinuous rilles including possible outcrops of bedrock and lobate lava flows from the domes. The observed Marius Hills are characterized by rough surface textures, including the presence of large boulders at the summits (~3-5m diameter), which is consistent with the radar-derived conclusions of [9]. Future investigations will involve analysis of LROC stereo photoclinometric products and coordinating NAC images with the multispectral images collected by the LROC WAC, especially the ultraviolet data, to enable measurements of color variations within and amongst deposits and provide possible compositional insights, including the location of possibly related pyroclastic deposits. References: [1] J. D. Stopar et al. (2009), LRO Science Targeting Meeting, Abs. 6039 [2] Greeley R (1971) Moon, 3, 289-314 [3] Guest J. E. (1971) Geol. and Phys. of the Moon, p. 41-53. [4] McCauley J. F. (1967) USGS Geologic Atlas of the Moon, Sheet I-491 [5] Weitz C. M. and Head J. W. (1999) JGR, 104, 18933-18956 [6] Heather D. J. et al. (2003) JGR, doi:10.1029/2002JE001938 [7] Whitford-Stark, J. L., and J. W. Head (1977) Proc. LSC 8th, 2705-2724 [8] Gruener J. and Joosten B. K. (2009) LRO Science Targeting Meeting, Abs. 6036 [9] Campbell B. A. et al. (2009) JGR, doi:10.1029/2008JE003253.

Regolith thickness over Sinus Iridum: Results from morphology and size-frequency distribution of small impact craters

NASA Astrophysics Data System (ADS)

Fa, Wenzhe; Liu, Tiantian; Zhu, Meng-Hua; Haruyama, Junichi

2014-08-01

High-resolution optical images returned from recent lunar missions provide a new chance for estimation of lunar regolith thickness using morphology and the size-frequency distribution of small impact craters. In this study, regolith thickness over the Sinus Iridum region is estimated using Lunar Reconnaissance Orbiter Camera (LROC) Narrow Angle Cameras (NACs) images. A revised relationship between crater geometry and regolith thickness is proposed based on old experimental data that takes into considering the effect of the illumination angle of the images. In total, 227 high-resolution LROC NAC images are used, and 378,556 impact craters with diameters from 4.2 to 249.8 m are counted, and their morphologies are identified. Our results show that 50% of the Sinus Iridum region has a regolith thickness between 5.1 and 10.7 m, and the mean and median regolith thicknesses are 8.5 and 8.0 m, respectively. There are substantial regional variations in the regolith thickness, with its median value varying from 2.6 to 12.0 m for most regions. Local variations of regolith thickness are found to be correlated with the lunar surface age: the older the surface, the greater the thickness. In addition, sporadically distributed impact ejecta and crater rays are associated with relatively larger regolith thickness, which might result from excavation and transport of materials during the formation of the secondaries of Copernican-aged craters. Our estimated regolith thickness can help with future analysis of Chang'E-3 lunar penetrating radar echoes and studies of the subsurface stratigraphic structure of the Moon.

Morphology and Composition of Localized Lunar Dark Mantle Deposits With LROC Data

NASA Astrophysics Data System (ADS)

Gustafson, O.; Bell, J. F.; Gaddis, L. R.; Hawke, B. R.; Robinson, M. S.; LROC Science Team

2010-12-01

Clementine color (ultraviolet, visible or UVVIS) and Lunar Reconnaissance Orbiter (LRO) Wide Angle (WAC) and Narrow Angle (NAC) camera data provide the means to investigate localized lunar dark-mantle deposits (DMDs) of potential pyroclastic origin. Our goals are to (1) examine the morphology and physical characteristics of these deposits with LROC WAC and NAC data; (2) extend methods used in earlier studies of lunar DMDs with Clementine spectral reflectance (CSR) data; (3) use LRO WAC multispectral data to complement and extend the CSR data for compositional analyses; and (4) apply these results to identify the likely mode of emplacement and study the diversity of compositions among these deposits. Pyroclastic deposits have been recognized all across the Moon, identified by their low albedo, smooth texture, and mantling relationship to underlying features. Gaddis et al. (2003) presented a compositional analysis of 75 potential lunar pyroclastic deposits (LPDs) based on CSR measurements. New LRO camera (LROC) data permit more extensive analyses of such deposits than previously possible. Our study began with six sites on the southeastern limb of the Moon that contain nine of the cataloged 75 potential pyroclastic deposits: Humboldt (4 deposits), Petavius, Barnard, Abel B, Abel C, and Titius. Our analysis found that some of the DMDs exhibit qualities characteristic of fluid emplacement, such as flat surfaces, sharp margins, embaying relationships, and flow textures. We conclude that the localized DMDs are a complex class of features, many of which may have formed by a combination of effusive and pyroclastic emplacement mechanisms. We have extended this analysis to include additional localized DMDs from the catalog of 75 potential pyroclastic deposits. We have examined high resolution (up to 0.5 m/p) NAC images as they become available to assess the mode of emplacement of the deposits, locate potential volcanic vents, and assess physical characteristics of the DMDs such as thickness, roughness, and rock abundance. Within and around each DMD, the Clementine UVVIS multispectral mosaic (100 m/p, 5 bands at 415, 750, 900, 950, and 1000 nm) and LROC WAC multispectral image cubes (75 to 400 m/p, 7 bands at 320, 360, 415, 565, 605, 645, and 690 nm) have been used to extract spectral reflectance data. Spectral ratio plots were prepared to compare deposits and draw conclusions regarding compositional differences, such as mafic mineral or titanium content and distribution, both within and between DMDs. The result of the study will be an improved classification of these deposits in terms of emplacement mechanisms and composition, including identifying compositional affinities among DMDs and between DMDs and other volcanic deposits.

New insight into lunar impact melt mobility from the LRO camera

USGS Publications Warehouse

Bray, Veronica J.; Tornabene, Livio L.; Keszthelyi, Laszlo P.; McEwen, Alfred S.; Hawke, B. Ray; Giguere, Thomas A.; Kattenhorn, Simon A.; Garry, William B.; Rizk, Bashar; Caudill, C.M.; Gaddis, Lisa R.; van der Bogert, Carolyn H.

2010-01-01

The Lunar Reconnaissance Orbiter Camera (LROC) is systematically imaging impact melt deposits in and around lunar craters at meter and sub-meter scales. These images reveal that lunar impact melts, although morphologically similar to terrestrial lava flows of similar size, exhibit distinctive features (e.g., erosional channels). Although generated in a single rapid event, the post-impact mobility and morphology of lunar impact melts is surprisingly complex. We present evidence for multi-stage influx of impact melt into flow lobes and crater floor ponds. Our volume and cooling time estimates for the post-emplacement melt movements noted in LROC images suggest that new flows can emerge from melt ponds an extended time period after the impact event.

Exploring the Moon at High-Resolution: First Results From the Lunar Reconnaissance Orbiter Camera (LROC)

NASA Astrophysics Data System (ADS)

Robinson, Mark; Hiesinger, Harald; McEwen, Alfred; Jolliff, Brad; Thomas, Peter C.; Turtle, Elizabeth; Eliason, Eric; Malin, Mike; Ravine, A.; Bowman-Cisneros, Ernest

The Lunar Reconnaissance Orbiter (LRO) spacecraft was launched on an Atlas V 401 rocket from the Cape Canaveral Air Force Station Launch Complex 41 on June 18, 2009. After spending four days in Earth-Moon transit, the spacecraft entered a three month commissioning phase in an elliptical 30×200 km orbit. On September 15, 2009, LRO began its planned one-year nominal mapping mission in a quasi-circular 50 km orbit. A multi-year extended mission in a fixed 30×200 km orbit is optional. The Lunar Reconnaissance Orbiter Camera (LROC) consists of a Wide Angle Camera (WAC) and two Narrow Angle Cameras (NACs). The WAC is a 7-color push-frame camera, which images the Moon at 100 and 400 m/pixel in the visible and UV, respectively, while the two NACs are monochrome narrow-angle linescan imagers with 0.5 m/pixel spatial resolution. LROC was specifically designed to address two of the primary LRO mission requirements and six other key science objectives, including 1) assessment of meter-and smaller-scale features in order to select safe sites for potential lunar landings near polar resources and elsewhere on the Moon; 2) acquire multi-temporal synoptic 100 m/pixel images of the poles during every orbit to unambiguously identify regions of permanent shadow and permanent or near permanent illumination; 3) meter-scale mapping of regions with permanent or near-permanent illumination of polar massifs; 4) repeat observations of potential landing sites and other regions to derive high resolution topography; 5) global multispectral observations in seven wavelengths to characterize lunar resources, particularly ilmenite; 6) a global 100-m/pixel basemap with incidence angles (60° -80° ) favorable for morphological interpretations; 7) sub-meter imaging of a variety of geologic units to characterize their physical properties, the variability of the regolith, and other key science questions; 8) meter-scale coverage overlapping with Apollo-era panoramic images (1-2 m/pixel) to document the number of small impacts since 1971-1972. LROC allows us to determine the recent impact rate of bolides in the size range of 0.5 to 10 meters, which is currently not well known. Determining the impact rate at these sizes enables engineering remediation measures for future surface operations and interplanetary travel. The WAC has imaged nearly the entire Moon in seven wavelengths. A preliminary global WAC stereo-based topographic model is in preparation [1] and global color processing is underway [2]. As the mission progresses repeat global coverage will be obtained as lighting conditions change providing a robust photometric dataset. The NACs are revealing a wealth of morpho-logic features at the meter scale providing the engineering and science constraints needed to support future lunar exploration. All of the Apollo landing sites have been imaged, as well as the majority of robotic landing and impact sites. Through the use of off-nadir slews a collection of stereo pairs is being acquired that enable 5-m scale topographic mapping [3-7]. Impact mor-phologies (terraces, impact melt, rays, etc) are preserved in exquisite detail at all Copernican craters and are enabling new studies of impact mechanics and crater size-frequency distribution measurements [8-12]. Other topical studies including, for example, lunar pyroclastics, domes, and tectonics are underway [e.g., 10-17]. The first PDS data release of LROC data will be in March 2010, and will include all images from the commissioning phase and the first 3 months of the mapping phase. [1] Scholten et al. (2010) 41st LPSC, #2111; [2] Denevi et al. (2010a) 41st LPSC, #2263; [3] Beyer et al. (2010) 41st LPSC, #2678; [4] Archinal et al. (2010) 41st LPSC, #2609; [5] Mattson et al. (2010) 41st LPSC, #1871; [6] Tran et al. (2010) 41st LPSC, #2515; [7] Oberst et al. (2010) 41st LPSC, #2051; [8] Bray et al. (2010) 41st LPSC, #2371; [9] Denevi et al. (2010b) 41st LPSC, #2582; [10] Hiesinger et al. (2010a) 41st LPSC, #2278; [11] Hiesinger et al. (2010b) 41st LPSC, #2304; [12] van der Bogert et al. (2010) 41st LPSC, #2165; [13] Plescia et al. (2010) 41st LPSC, #2160; [14] Lawrence et al. (2010) 41st LPSC, #1906; [15] Gaddis et al. (2010) 41st LPSC, #2059; [16] Watters et al. (2010) 41st LPSC, #1863; [17] Garry et al. (2010) 41st LPSC, #2278.

Regolith Gardening Caused by Recent Lunar Impacts Observed by the Lunar Reconnaissance Obiter Camera

NASA Astrophysics Data System (ADS)

Speyerer, E. J.

2016-12-01

Temporal observations by the Lunar Reconnaissance Obiter Camera (LROC) Narrow Angle Camera (NAC) enable us to map and measure the spatial distribution of ejecta as well as quantify faint distal zones that may be the result of early stage jetting caused by meteoroid impacts. These detailed before and after observations enable the examination of surface reflectance changes as well as the analysis of nearby features (i.e. highly degraded craters, secondary craters, and new/spatially shifted boulders). In addition, NAC temporal pairs reveal numerous areas where the regolith has been churned and modified. These features, which we refer to as splotches, are most likely caused by small secondary impacts due to their high population near recent impact events [Robinson et al., 2015]. Using over 14,000 NAC temporal pairs, we identified over 47,000 splotches and quantified their spatial coverage and rate of formation. Based on the observed size frequency distribution, our models indicate that 99% of the entire lunar surface is modified by 1 m in diameter and larger splotches over a period of 8.1x10^4 years. These splotches have the potential to churn the upper few cm of regolith, which influence the local surface roughness and ultimately the surface reflectance observed from orbit. This new churning rate estimate is consistent with previous analysis of regolith properties within drive core samples acquired during the Apollo missions; these cores reveal that the upper 2 cm was rapidly and continuously modified over periods of <=10^5 years [Fruchter et al., 1977]. Overall, the examination of LROC NAC temporal pairs enables detailed studies of the impact process on a scale that exceeds laboratory experiments. Continued collection of NAC temporal pairs during the LRO Cornerstone Mission and future extended missions will aid in the discovery of new, larger impact craters and other contemporary surface changes. References:Fruchter et al. 1977. Proc. Lunar Planet Sci. Conf. 8th. pp. 3595-3605. Robinson et al. 2015. Icarus 252, 229-235.

Boulder Distributions at Legacy Landing Sites: Assessing Regolith Production Rates and Landing Site Hazards

NASA Technical Reports Server (NTRS)

Watkins, R. N.; Jolliff, B. L.; Lawrence, S. J.; Hayne, P. O.; Ghent, R. R.

2017-01-01

Understanding how the distribution of boulders on the lunar surface changes over time is key to understanding small-scale erosion processes and the rate at which rocks become regolith. Boulders degrade over time, primarily as a result of micrometeorite bombardment so their residence time at the surface can inform the rate at which rocks become regolith or become buried within regolith. Because of the gradual degradation of exposed boulders, we expect that the boulder population around an impact crater will decrease as crater age increases. Boulder distributions around craters of varying ages are needed to understand regolith production rates, and Lunar Reconnaissance Orbiter Camera (LROC) Narrow Angle Camera (NAC) images provide one of the best tools for conducting these studies. Using NAC images to assess how the distribution of boulders varies as a function of crater age provides key constraints for boulder erosion processes. Boulders also represent a potential hazard that must be addressed in the planning of future lunar landings. A boulder under a landing leg can contribute to deck tilt, and boulders can damage spacecraft during landing. Using orbital data to characterize boulder populations at locations where landers have safely touched down (Apollo, Luna, Surveyor, Chang'e-3) provides validation for landed mission hazard avoidance planning. Additionally, counting boulders at legacy landing sites is useful because: 1) LROC has extensive coverage of these sites at high resolutions (approximately 0.5 meters per pixel). 2) Returned samples from craters at these sites have been radiometrically dated, allowing assessment of how boulder distributions vary as a function of crater age. 3) Surface photos at these sites can be used to correlate with remote sensing measurements.

Effects of illumination differences on photometric stereo shape-and-albedo-from-shading for precision lunar surface reconstruction

NASA Astrophysics Data System (ADS)

Chung Liu, Wai; Wu, Bo; Wöhler, Christian

2018-02-01

Photoclinometric surface reconstruction techniques such as Shape-from-Shading (SfS) and Shape-and-Albedo-from-Shading (SAfS) retrieve topographic information of a surface on the basis of the reflectance information embedded in the image intensity of each pixel. SfS or SAfS techniques have been utilized to generate pixel-resolution digital elevation models (DEMs) of the Moon and other planetary bodies. Photometric stereo SAfS analyzes images under multiple illumination conditions to improve the robustness of reconstruction. In this case, the directional difference in illumination between the images is likely to affect the quality of the reconstruction result. In this study, we quantitatively investigate the effects of illumination differences on photometric stereo SAfS. Firstly, an algorithm for photometric stereo SAfS is developed, and then, an error model is derived to analyze the relationships between the azimuthal and zenith angles of illumination of the images and the reconstruction qualities. The developed algorithm and error model were verified with high-resolution images collected by the Narrow Angle Camera (NAC) of the Lunar Reconnaissance Orbiter Camera (LROC). Experimental analyses reveal that (1) the resulting error in photometric stereo SAfS depends on both the azimuthal and the zenith angles of illumination as well as the general intensity of the images and (2) the predictions from the proposed error model are consistent with the actual slope errors obtained by photometric stereo SAfS using the LROC NAC images. The proposed error model enriches the theory of photometric stereo SAfS and is of significance for optimized lunar surface reconstruction based on SAfS techniques.

Lunar Reconnaissance Orbiter Data Enable Science and Terrain Analysis of Potential Landing Sites in South Pole-Aitken Basin

NASA Astrophysics Data System (ADS)

Jolliff, B. L.

2017-12-01

Exploring the South Pole-Aitken basin (SPA), one of the key unsampled geologic terranes on the Moon, is a high priority for Solar System science. As the largest and oldest recognizable impact basin on the Moon, it anchors the heavy bombardment chronology. It is thus a key target for sample return to better understand the impact flux in the Solar System between formation of the Moon and 3.9 Ga when Imbrium, one of the last of the great lunar impact basins, formed. Exploration of SPA has implications for understanding early habitable environments on the terrestrial planets. Global mineralogical and compositional data exist from the Clementine UV-VIS camera, the Lunar Prospector Gamma Ray Spectrometer, the Moon Mineralogy Mapper (M3) on Chandrayaan-1, the Chang'E-1 Imaging Interferometer, the spectral suite on SELENE, and the Lunar Reconnaissance Orbiter Cameras (LROC) Wide Angle Camera (WAC) and Diviner thermal radiometer. Integration of data sets enables synergistic assessment of geology and distribution of units across multiple spatial scales. Mineralogical assessment using hyperspectral data indicates spatial relationships with mineralogical signatures, e.g., central peaks of complex craters, consistent with inferred SPA basin structure and melt differentiation (Moriarty & Pieters, 2015, JGR-P 118). Delineation of mare, cryptomare, and nonmare surfaces is key to interpreting compositional mixing in the formation of SPA regolith to interpret remotely sensed data, and for scientific assessment of landing sites. LROC Narrow Angle Camera (NAC) images show the location and distribution of >0.5 m boulders and fresh craters that constitute the main threats to automated landers and thus provide critical information for landing site assessment and planning. NAC images suitable for geometric stereo derivation and digital terrain models so derived, controlled with Lunar Orbiter Laser Altimeter (LOLA) data, and oblique NAC images made with large slews of the spacecraft, are crucial to both scientific and landing-site assessments. These images, however, require favorable illumination and significant spacecraft resources. Thus they make up only a small percentage of all of the images taken. It is essential for future exploration to support LRO continued operation for these critical datasets.

The Moon's North Pole

NASA Image and Video Library

2017-12-08

NASA image release September 7, 2011 The Earth's moon has been an endless source of fascination for humanity for thousands of years. When at last Apollo 11 landed on the moon's surface in 1969, the crew found a desolate, lifeless orb, but one which still fascinates scientist and non-scientist alike. This image of the moon's north polar region was taken by the Lunar Reconnaissance Orbiter Camera, or LROC. One of the primary scientific objectives of LROC is to identify regions of permanent shadow and near-permanent illumination. Since the start of the mission, LROC has acquired thousands of Wide Angle Camera images approaching the north pole. From these images, scientists produced this mosaic, which is composed of 983 images taken over a one month period during northern summer. This mosaic shows the pole when it is best illuminated, regions that are in shadow are candidates for permanent shadow. Image Credit: NASA/GSFC/Arizona State University NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

Experiences Supporting the Lunar Reconnaissance Orbiter Camera: the Devops Model

NASA Astrophysics Data System (ADS)

Licht, A.; Estes, N. M.; Bowman-Cisnesros, E.; Hanger, C. D.

2013-12-01

Introduction: The Lunar Reconnaissance Orbiter Camera (LROC) Science Operations Center (SOC) is responsible for instrument targeting, product processing, and archiving [1]. The LROC SOC maintains over 1,000,000 observations with over 300 TB of released data. Processing challenges compound with the acquisition of over 400 Gbits of observations daily creating the need for a robust, efficient, and reliable suite of specialized software. Development Environment: The LROC SOC's software development methodology has evolved over time. Today, the development team operates in close cooperation with the systems administration team in a model known in the IT industry as DevOps. The DevOps model enables a highly productive development environment that facilitates accomplishment of key goals within tight schedules[2]. The LROC SOC DevOps model incorporates industry best practices including prototyping, continuous integration, unit testing, code coverage analysis, version control, and utilizing existing open source software. Scientists and researchers at LROC often prototype algorithms and scripts in a high-level language such as MATLAB or IDL. After the prototype is functionally complete the solution is implemented as production ready software by the developers. Following this process ensures that all controls and requirements set by the LROC SOC DevOps team are met. The LROC SOC also strives to enhance the efficiency of the operations staff by way of weekly presentations and informal mentoring. Many small scripting tasks are assigned to the cognizant operations personnel (end users), allowing for the DevOps team to focus on more complex and mission critical tasks. In addition to leveraging open source software the LROC SOC has also contributed to the open source community by releasing Lunaserv [3]. Findings: The DevOps software model very efficiently provides smooth software releases and maintains team momentum. Scientists prototyping their work has proven to be very efficient as developers do not need to spend time iterating over small changes. Instead, these changes are realized in early prototypes and implemented before the task is seen by developers. The development practices followed by the LROC SOC DevOps team help facilitate a high level of software quality that is necessary for LROC SOC operations. Application to the Scientific Community: There is no replacement for having software developed by professional developers. While it is beneficial for scientists to write software, this activity should be seen as prototyping, which is then made production ready by professional developers. When constructed properly, even a small development team has the ability to increase the rate of software development for a research group while creating more efficient, reliable, and maintainable products. This strategy allows scientists to accomplish more, focusing on teamwork, rather than software development, which may not be their primary focus. 1. Robinson et al. (2010) Space Sci. Rev. 150, 81-124 2. DeGrandis. (2011) Cutter IT Journal. Vol 24, No. 8, 34-39 3. Estes, N.M.; Hanger, C.D.; Licht, A.A.; Bowman-Cisneros, E.; Lunaserv Web Map Service: History, Implementation Details, Development, and Uses, http://adsabs.harvard.edu/abs/2013LPICo1719.2609E.

Lunar Reconnaissance Orbiter Camera

Science.gov Websites

them out » Traverse featurette Traverse the Apollo Landing Sites & More. By combining LROC imagery , data, and historical data, we've created detailed, interactive maps of the Apollo Landing Sites and taken by the original Apollo crews. ASU maintains the Apollo Digital Image Archive and the March to the

The Far Side of the Moon -- And All the Way Around

NASA Image and Video Library

2011-03-11

NASA image release March 11, 2011 Caption: The lunar farside as never seen before! LROC WAC orthographic projection centered at 180° longitude, 0° latitude. Credit: NASA/Goddard/Arizona State University. Because the moon is tidally locked (meaning the same side always faces Earth), it was not until 1959 that the farside was first imaged by the Soviet Luna 3 spacecraft (hence the Russian names for prominent farside features, such as Mare Moscoviense). And what a surprise - unlike the widespread maria on the nearside, basaltic volcanism was restricted to a relatively few, smaller regions on the farside, and the battered highlands crust dominated. A different world from what we saw from Earth. Of course, the cause of the farside/nearside asymmetry is an interesting scientific question. Past studies have shown that the crust on the farside is thicker, likely making it more difficult for magmas to erupt on the surface, limiting the amount of farside mare basalts. Why is the farside crust thicker? That is still up for debate, and in fact several presentations at this week's Lunar and Planetary Science Conference attempt to answer this question. The Clementine mission obtained beautiful mosaics with the sun high in the sky (low phase angles), but did not have the opportunity to observe the farside at sun angles favorable for seeing surface topography. This WAC mosaic provides the most complete look at the morphology of the farside to date, and will provide a valuable resource for the scientific community. And it's simply a spectacular sight! The Lunar Reconnaissance Orbiter Camera (LROC) Wide Angle Camera (WAC) is a push-frame camera that captures seven color bands (321, 360, 415, 566, 604, 643, and 689 nm) with a 57-km swath (105-km swath in monochrome mode) from a 50 km orbit. One of the primary objectives of LROC is to provide a global 100 m/pixel monochrome (643 nm) base map with incidence angles between 55°-70° at the equator, lighting that is favorable for morphological interpretations. Each month, the WAC provides nearly complete coverage of the Moon under unique lighting. As an added bonus, the orbit-to-orbit image overlap provides stereo coverage. Reducing all these stereo images into a global topographic map is a big job, and is being led by LROC Team Members from the German Aerospace Center (Deutsches Zentrum für Luft- und Raumfahrt; DLR). Several preliminary WAC topographic products have appeared in LROC featured images over the past year (Orientale basin, Sinus Iridum). For a sneak preview of the WAC global DEM with the WAC global mosaic, view a rotating composite moon (70 MB video from ASU's LROC website). The WAC topographic dataset will be completed and released later this year. The global mosaic released today is comprised of over 15,000 WAC images acquired between November 2009 and February 2011. The non-polar images were map projected onto the GLD100 shape model (WAC derived 100 m/pixel DTM), while polar images were map projected on the LOLA shape model. In addition, the LOLA derived crossover corrected ephemeris, and an improved camera pointing, provide accurate positioning (better than 100 m) of each WAC image. As part of the March 2011 PDS release, the LROC team posted the global map in ten regional tiles. Eight of the tiles are equirectangular projections that encompass 60° latitude by 90° longitude. In addition, two polar stereographic projections are available for each pole from ±60° to the pole. These reduced data records (RDR) products will be available for download on March 15, 2011. As the mission progresses, and our knowledge of the lunar photometric function increases, improved and new mosaics will be released! Work your way around the moon with these six orthographic projections constructed from WAC mosaics. The nearside view linked below is different from that released on 21 February. To read more con't here: www.nasa.gov/mission_pages/LRO/news/lro-farside.html NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Join us on Facebook

The Effects of Terrain Properties on Determining Crater Model Ages of Lunar Surfaces

NASA Astrophysics Data System (ADS)

Kirchoff, M. R.; Marchi, S.

2017-12-01

Analyzing crater size-frequency distributions (SFDs) and using them to determine model ages of surfaces is an important technique for understanding the Moon's geologic history and evolution. Small craters with diameters (D) < 1 km are frequently used, especially given the very high resolution imaging now available from Lunar Reconnaissance Orbiter Narrow and Wide Angle Cameras (LROC-NAC/WAC) and the Selene Terrain Camera. However, for these diameters, final crater sizes and shapes are affected by the properties of the terrains on which they are formed [1], which alters crater SFD shapes [2]. We use the Model Production Function (MPF; [2]), which includes terrain properties in computing crater production functions, to explore how incorporating terrain properties affects the estimation of crater model ages. First, crater SFDs are compiled utilizing LROC-WAC/NAC images to measure craters with diameters from 10 m up to 20 km (size of largest crater measured depends on the terrain). A nested technique is used to obtain this wide diameter range: D ≥ 0.5 km craters are measured in the largest area, D = 0.09-0.5 km craters are measured in a smaller area within the largest area, and D = 0.01-0.1 km craters are measured in the smallest area located in both of the larger areas. Then, we quantitatively fit the crater SFD with distinct MPFs that use broadly different terrain properties. Terrain properties are varied through coarsely altering the parameters in the crater scaling law [1] that represent material type (consolidated, unconsolidated, porous), material tensile strength, and material density (for further details see [2]). We also discuss the effect of changing terrain properties with depth (i.e., layering). Finally, fits are used to compute the D = 1 km crater model ages for the terrains. We discuss the new constraints on how terrain properties affect crater model ages from our analyses of a variety of lunar terrains from highlands to mare and impact melt to continuous ejecta deposits. References: [1] Holsapple, K. A & Housen, K. R., Icarus 187, 345-356, 2007. [2] Marchi, S., et al., AJ 137, 4936-4948, 2009.

Frequency-Range Distribution of Boulders Around Cone Crater: Relevance to Landing Site Hazard Avoidance

NASA Technical Reports Server (NTRS)

Clegg-Watkins, R. N.; Jolliff, B. L.; Lawrence, S. J.

2016-01-01

Boulders represent a landing hazard that must be addressed in the planning of future landings on the Moon. A boulder under a landing leg can contribute to deck tilt and boulders can damage spacecraft during landing. Using orbital data to characterize boulder populations at locations where landers have safely touched down (Apollo, Luna, Surveyor, and Chang'e-3 sites) is important for determining landing hazard criteria for future missions. Additionally, assessing the distribution of boulders can address broader science issues, e.g., how far craters distribute boulders and how this distribution varies as a function of crater size and age. The availability of new Lunar Reconnaissance Orbiter Camera (LROC) Narrow Angle Camera (NAC) images [1] enables the use of boulder size- and range frequency distributions for a variety of purposes [2-6]. Boulders degrade over time and primarily occur around young or fresh craters that are large enough to excavate bedrock. Here we use NAC images to analyze boulder distributions around Cone crater (340 m diameter) at the Apollo 14 site. Cone crater (CC) was selected because it is the largest crater where astronaut surface photography is available for a radial traverse to the rim. Cone crater is young (approximately 29 Ma [7]) relative to the time required to break down boulders [3,8], giving us a data point for boulder range-frequency distributions (BRFDs) as a function of crater age.

Occurrence probability of slopes on the lunar surface: Estimate by the shaded area percentage in the LROC NAC images

NASA Astrophysics Data System (ADS)

Abdrakhimov, A. M.; Basilevsky, A. T.; Ivanov, M. A.; Kokhanov, A. A.; Karachevtseva, I. P.; Head, J. W.

2015-09-01

The paper describes the method of estimating the distribution of slopes by the portion of shaded areas measured in the images acquired at different Sun elevations. The measurements were performed for the benefit of the Luna-Glob Russian mission. The western ellipse for the spacecraft landing in the crater Bogus-lawsky in the southern polar region of the Moon was investigated. The percentage of the shaded area was measured in the images acquired with the LROC NAC camera with a resolution of ~0.5 m. Due to the close vicinity of the pole, it is difficult to build digital terrain models (DTMs) for this region from the LROC NAC images. Because of this, the method described has been suggested. For the landing ellipse investigated, 52 LROC NAC images obtained at the Sun elevation from 4° to 19° were used. In these images the shaded portions of the area were measured, and the values of these portions were transferred to the values of the occurrence of slopes (in this case, at the 3.5-m baseline) with the calibration by the surface characteristics of the Lunokhod-1 study area. For this area, the digital terrain model of the ~0.5-m resolution and 13 LROC NAC images obtained at different elevations of the Sun are available. From the results of measurements and the corresponding calibration, it was found that, in the studied landing ellipse, the occurrence of slopes gentler than 10° at the baseline of 3.5 m is 90%, while it is 9.6, 5.7, and 3.9% for the slopes steeper than 10°, 15°, and 20°, respectively. Obviously, this method can be recommended for application if there is no DTM of required granularity for the regions of interest, but there are high-resolution images taken at different elevations of the Sun.

Surveying the Newly Digitized Apollo Metric Images for Highland Fault Scarps on the Moon

NASA Astrophysics Data System (ADS)

Williams, N. R.; Pritchard, M. E.; Bell, J. F.; Watters, T. R.; Robinson, M. S.; Lawrence, S.

2009-12-01

The presence and distribution of thrust faults on the Moon have major implications for lunar formation and thermal evolution. For example, thermal history models for the Moon imply that most of the lunar interior was initially hot. As the Moon cooled over time, some models predict global-scale thrust faults should form as stress builds from global thermal contraction. Large-scale thrust fault scarps with lengths of hundreds of kilometers and maximum relief of up to a kilometer or more, like those on Mercury, are not found on the Moon; however, relatively small-scale linear and curvilinear lobate scarps with maximum lengths typically around 10 km have been observed in the highlands [Binder and Gunga, Icarus, v63, 1985]. These small-scale scarps are interpreted to be thrust faults formed by contractional stresses with relatively small maximum (tens of meters) displacements on the faults. These narrow, low relief landforms could only be identified in the highest resolution Lunar Orbiter and Apollo Panoramic Camera images and under the most favorable lighting conditions. To date, the global distribution and other properties of lunar lobate faults are not well understood. The recent micron-resolution scanning and digitization of the Apollo Mapping Camera (Metric) photographic negatives [Lawrence et al., NLSI Conf. #1415, 2008; http://wms.lroc.asu.edu/apollo] provides a new dataset to search for potential scarps. We examined more than 100 digitized Metric Camera image scans, and from these identified 81 images with favorable lighting (incidence angles between about 55 and 80 deg.) to manually search for features that could be potential tectonic scarps. Previous surveys based on Panoramic Camera and Lunar Orbiter images found fewer than 100 lobate scarps in the highlands; in our Apollo Metric Camera image survey, we have found additional regions with one or more previously unidentified linear and curvilinear features on the lunar surface that may represent lobate thrust fault scarps. In this presentation we review the geologic characteristics and context of these newly-identified, potentially tectonic landforms. The lengths and relief of some of these linear and curvilinear features are consistent with previously identified lobate scarps. Most of these features are in the highlands, though a few occur along the edges of mare and/or crater ejecta deposits. In many cases the resolution of the Metric Camera frames (~10 m/pix) is not adequate to unequivocally determine the origin of these features. Thus, to assess if the newly identified features have tectonic or other origins, we are examining them in higher-resolution Panoramic Camera (currently being scanned) and Lunar Reconnaissance Orbiter Camera Narrow Angle Camera images [Watters et al., this meeting, 2009].

Inferred Lunar Boulder Distributions at Decimeter Scales

NASA Technical Reports Server (NTRS)

Baloga, S. M.; Glaze, L. S.; Spudis, P. D.

2012-01-01

Block size distributions of impact deposits on the Moon are diagnostic of the impact process and environmental effects, such as target lithology and weathering. Block size distributions are also important factors in trafficability, habitability, and possibly the identification of indigenous resources. Lunar block sizes have been investigated for many years for many purposes [e.g., 1-3]. An unresolved issue is the extent to which lunar block size distributions can be extrapolated to scales smaller than limits of resolution of direct measurement. This would seem to be a straightforward statistical application, but it is complicated by two issues. First, the cumulative size frequency distribution of observable boulders rolls over due to resolution limitations at the small end. Second, statistical regression provides the best fit only around the centroid of the data [4]. Confidence and prediction limits splay away from the best fit at the endpoints resulting in inferences in the boulder density at the CPR scale that can differ by many orders of magnitude [4]. These issues were originally investigated by Cintala and McBride [2] using Surveyor data. The objective of this study was to determine whether the measured block size distributions from Lunar Reconnaissance Orbiter Camera - Narrow Angle Camera (LROC-NAC) images (m-scale resolution) can be used to infer the block size distribution at length scales comparable to Mini-RF Circular Polarization Ratio (CPR) scales, nominally taken as 10 cm. This would set the stage for assessing correlations of inferred block size distributions with CPR returns [6].

NASA Releases New High-Resolution Earthrise Image

NASA Image and Video Library

2017-12-08

NASA's Lunar Reconnaissance Orbiter (LRO) recently captured a unique view of Earth from the spacecraft's vantage point in orbit around the moon. "The image is simply stunning," said Noah Petro, Deputy Project Scientist for LRO at NASA's Goddard Space Flight Center in Greenbelt, Maryland. "The image of the Earth evokes the famous 'Blue Marble' image taken by Astronaut Harrison Schmitt during Apollo 17, 43 years ago, which also showed Africa prominently in the picture." In this composite image we see Earth appear to rise over the lunar horizon from the viewpoint of the spacecraft, with the center of the Earth just off the coast of Liberia (at 4.04 degrees North, 12.44 degrees West). The large tan area in the upper right is the Sahara Desert, and just beyond is Saudi Arabia. The Atlantic and Pacific coasts of South America are visible to the left. On the moon, we get a glimpse of the crater Compton, which is located just beyond the eastern limb of the moon, on the lunar farside. LRO was launched on June 18, 2009, and has collected a treasure trove of data with its seven powerful instruments, making an invaluable contribution to our knowledge about the moon. LRO experiences 12 earthrises every day; however the spacecraft is almost always busy imaging the lunar surface so only rarely does an opportunity arise such that its camera instrument can capture a view of Earth. Occasionally LRO points off into space to acquire observations of the extremely thin lunar atmosphere and perform instrument calibration measurements. During these movements sometimes Earth (and other planets) pass through the camera's field of view and dramatic images such as the one shown here are acquired. This image was composed from a series of images taken Oct. 12, when LRO was about 83 miles (134 kilometers) above the moon's farside crater Compton. Capturing an image of the Earth and moon with LRO's Lunar Reconnaissance Orbiter Camera (LROC) instrument is a complicated task. First the spacecraft must be rolled to the side (in this case 67 degrees), then the spacecraft slews with the direction of travel to maximize the width of the lunar horizon in LROC's Narrow Angle Camera image. All this takes place while LRO is traveling faster than 3,580 miles per hour (over 1,600 meters per second) relative to the lunar surface below the spacecraft! The high-resolution Narrow Angle Camera (NAC) on LRO takes black-and-white images, while the lower resolution Wide Angle Camera (WAC) takes color images, so you might wonder how we got a high-resolution picture of the Earth in color. Since the spacecraft, Earth, and moon are all in motion, we had to do some special processing to create an image that represents the view of the Earth and moon at one particular time. The final Earth image contains both WAC and NAC information. WAC provides the color, and the NAC provides high-resolution detail. "From the Earth, the daily moonrise and moonset are always inspiring moments," said Mark Robinson of Arizona State University in Tempe, principal investigator for LROC. "However, lunar astronauts will see something very different: viewed from the lunar surface, the Earth never rises or sets. Since the moon is tidally locked, Earth is always in the same spot above the horizon, varying only a small amount with the slight wobble of the moon. The Earth may not move across the 'sky', but the view is not static. Future astronauts will see the continents rotate in and out of view and the ever-changing pattern of clouds will always catch one's eye, at least on the nearside. The Earth is never visible from the farside; imagine a sky with no Earth or moon - what will farside explorers think with no Earth overhead?" NASA's first Earthrise image was taken with the Lunar Orbiter 1 spacecraft in 1966. Perhaps NASA's most iconic Earthrise photo was taken by the crew of the Apollo 8 mission as the spacecraft entered lunar orbit on Christmas Eve Dec. 24, 1968. That evening, the astronauts -- Commander Frank Borman, Command Module Pilot Jim Lovell, and Lunar Module Pilot William Anders -- held a live broadcast from lunar orbit, in which they showed pictures of the Earth and moon as seen from their spacecraft. Said Lovell, "The vast loneliness is awe-inspiring and it makes you realize just what you have back there on Earth." Credit: NASA/Goddard/Arizona State University NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

KSC-2009-2989

NASA Image and Video Library

2009-05-08

CAPE CANAVERAL, Fla. – At Astrotech Space Operations in Titusville, Fla., technicians photograph the Lunar Reconnaissance Orbiter, or LRO, during closeout before its mating with NASA's Lunar CRater Observation and Sensing Satellite, known as LCROSS, spacecraft. Instruments on the LRO include the LEND that will measure the flux of neutrons from the moon; the LROC, a narrow angle camera that will provide panchromatic images; the LOLA, which will provide a precise global lunar topographic model and geodetic grid; and top right, the DIVINER, which will measure lunar surface temperatures at scales that provide essential information for future surface operations and exploration; and at top, the CRaTER, which will characterize the global lunar radiation environment and its biological impacts. At right is the solar panel. The satellite's primary mission is to search for water ice on the moon in a permanently shadowed crater near one of the lunar poles. LCROSS is a low-cost, accelerated-development, companion mission to NASA's Lunar Reconnaissance Orbiter, or LRO. LCROSS and LRO are the first missions in NASA's plan to return humans to the moon and begin establishing a lunar outpost by 2020. Launch is targeted for no earlier than June 2 from Cape Canaveral Air Force Station in Florida. Photo credit: NASA/Jack Pfaller

KSC-2009-2988

NASA Image and Video Library

2009-05-08

CAPE CANAVERAL, Fla. – Another view of the Lunar Reconnaissance Orbiter, or LRO, at Astrotech Space Operations in Titusville, Fla., during closeout before its mating with NASA's Lunar CRater Observation and Sensing Satellite, known as LCROSS, spacecraft. Instruments seen, at left, are (from bottom) the LEND that will measure the flux of neutrons from the moon; the LROC, a narrow angle camera that will provide panchromatic images; the LOLA, which will provide a precise global lunar topographic model and geodetic grid; and top right, the DIVINER, which will measure lunar surface temperatures at scales that provide essential information for future surface operations and exploration; and at top, the CRaTER, which will characterize the global lunar radiation environment and its biological impacts. At right is the solar panel. The satellite's primary mission is to search for water ice on the moon in a permanently shadowed crater near one of the lunar poles. LCROSS is a low-cost, accelerated-development, companion mission to NASA's Lunar Reconnaissance Orbiter, or LRO. LCROSS and LRO are the first missions in NASA's plan to return humans to the moon and begin establishing a lunar outpost by 2020. Launch is targeted for no earlier than June 2 from Cape Canaveral Air Force Station in Florida. Photo credit: NASA/Jack Pfaller

Morphologic Analysis of Lunar Craters in the Simple-to-Complex Transition

NASA Astrophysics Data System (ADS)

Chandnani, M.; Herrick, R. R.; Kramer, G. Y.

2015-12-01

The diameter range of 15 km to 20 km on the Moon is within the transition from simple to complex impact craters. We examined 207 well preserved craters in this diameter range distributed across the moon using high resolution Lunar Reconnaissance Orbiter Camera Wide Angle Camera Mosaic (WAC) and Narrow Angle Camera (NAC) data. A map of the distribution of the 207 craters on the Moon using the global LROC WAC mosaic has been attahced with the abstract. By examining craters of similar diameter, impact energy is nearly constant, so differences in shape and morphology must be due to either target (e.g., porosity, density, coherence, layering) or impactor (e.g., velocity, density) properties. On the basis of the crater morphology, topographic profiles and depth-diameter ratio, the craters were classified into simple, craters with slumped walls, craters with both slumping and terracing, those containing a central uplift only, those with a central uplift and slumping, and the craters with a central uplift accompanied by both slumping and terracing, as shown in the image. It was observed that simple craters and craters with slumped walls occur predominately on the lunar highlands. The majority of the craters with terraced walls and all classes of central uplifts were observed predominately on the mare. In short, in this size range craters in the highlands were generally simple craters with occasionally some slumped material in the center, and the more developed features (terracing, central peak) were associated with mare craters. This is somewhat counterintuitive, as we expect the highlands to be generally weaker and less consolidated than the mare. We hypothesize that the presence of rheologic layering in the mare may be the cause of the more complex features that we observe. Relatively weak layers in the mare could develop through regolith formation between individual flows, or perhaps by variations within or between the flows themselves.

Documenting of Geologic Field Activities in Real-Time in Four Dimensions: Apollo 17 as a Case Study for Terrestrial Analogues and Future Exploration

NASA Technical Reports Server (NTRS)

Feist, B.; Bleacher, J. E.; Petro, N. E.; Niles, P. B.

2018-01-01

During the Apollo exploration of the lunar surface, thousands of still images, 16 mm videos, TV footage, samples, and surface experiments were captured and collected. In addition, observations and descriptions of what was observed was radioed to Mission Control as part of standard communications and subsequently transcribed. The archive of this material represents perhaps the best recorded set of geologic field campaigns and will serve as the example of how to conduct field work on other planetary bodies for decades to come. However, that archive of material exists in disparate locations and formats with varying levels of completeness, making it not easily cross-referenceable. While video and audio exist for the missions, it is not time synchronized, and images taken during the missions are not time or location tagged. Sample data, while robust, is not easily available in a context of where the samples were collected, their descriptions by the astronauts are not connected to them, or the video footage of their collection (if available). A more than five year undertaking to reconstruct and reconcile the Apollo 17 mission archive, from launch through splashdown, has generated an integrated record of the entire mission, resulting in searchable, synchronized image, voice, and video data, with geologic context provided at the time each sample was collected. Through www.apollo17.org the documentation of the field investigation conducted by the Apollo 17 crew is presented in chronologic sequence, with additional context provided by high-resolution Lunar Reconnaissance Orbiter Camera (LROC) Narrow Angle Camera (NAC) images and a corresponding digital terrain model (DTM) of the Taurus-Littrow Valley.

The Absolute Reflectance and New Calibration Site of the Moon

NASA Astrophysics Data System (ADS)

Wu, Yunzhao; Wang, Zhenchao; Cai, Wei; Lu, Yu

2018-05-01

How bright the Moon is forms a simple but fundamental and important question. Although numerous efforts have been made to answer this question such as use of sophisticated electro-optical measurements and suggestions for calibration sites, the answer is still debated. An in situ measurement with a calibration panel on the surface of the Moon is crucial for obtaining the accurate absolute reflectance and resolving the debate. China’s Chang’E-3 (CE-3) “Yutu” rover accomplished this type of measurement using the Visible-Near Infrared Spectrometer (VNIS). The measurements of the VNIS, which were at large emission and phase angles, complement existing measurements for the range of photometric geometry. The in situ reflectance shows that the CE-3 landing site is very dark with an average reflectance of 3.86% in the visible bands. The results are compared with recent mission instruments: the Lunar Reconnaissance Orbiter Camera (LROC) Wide Angle Camera (WAC), the Spectral Profiler (SP) on board the SELENE, the Moon Mineralogy Mapper (M3) on board the Chandrayaan-1, and the Chang’E-1 Interference Imaging Spectrometer (IIM). The differences in the measurements of these instruments are very large and indicate inherent differences in their absolute calibration. The M3 and IIM measurements are smaller than LROC WAC and SP, and the VNIS measurement falls between these two pairs. When using the Moon as a radiance source for the on-orbit calibration of spacecraft instruments, one should be cautious about the data. We propose that the CE-3 landing site, a young and homogeneous surface, should serve as the new calibration site.

Reconditioning of Cassini Narrow-Angle Camera

NASA Image and Video Library

2002-07-23

These five images of single stars, taken at different times with the narrow-angle camera on NASA Cassini spacecraft, show the effects of haze collecting on the camera optics, then successful removal of the haze by warming treatments.

Relative depths of simple craters and the nature of the lunar regolith

NASA Astrophysics Data System (ADS)

Stopar, Julie D.; Robinson, Mark S.; Barnouin, Olivier S.; McEwen, Alfred S.; Speyerer, Emerson J.; Henriksen, Megan R.; Sutton, Sarah S.

2017-12-01

We assessed the morphologies of more than 930 simple impact craters (diameters 40 m-10 km) on the Moon using digital terrain models (DTMs) of a variety of terrains in order to characterize the variability of fresh crater morphology as a function of crater diameter. From Lunar Reconnaissance Orbiter Camera (LROC) Narrow Angle Camera (NAC) DTMs, we determined depth-to-diameter (d/D) ratios for an extremely fresh set of these craters with diameters less than 400 m and found that their d/D ratios range from 0.11 to 0.17. Using both NAC and Kaguya Terrain Camera DTMs, we also determined the d/D ratios for the set of fresh simple craters larger than 400 m in diameter. The d/D ratios of these larger craters are typically near 0.21, as expected of gravity-dominated crater excavation. Fresh craters less than ∼400 m in diameter, on the other hand, exhibit significantly lower d/D ratios. Various possible factors affect the morphologies and relative depths (d/D ratios) of small strength-dominated craters, including impactor and target properties (e.g., effective strength, strength contrasts, porosity, pre-existing weaknesses), impact angle and velocity, and degradation state. While impact conditions resulting from secondary impacts can also affect crater morphologies, we found that d/D ratio alone was not a unique discriminator of small secondary craters. To investigate the relative influences of degradation and target properties on the d/D ratios of small strength-dominated craters, we examined a subset of fresh craters located on the geologically young rim deposits of Tycho crater. These craters are deeper and steeper than other craters of similar diameter and degradation state, consistent with their relative freshness and formation in the relatively coherent, melt-rich deposits in this region. The d/D ratios of globally distributed small craters of similar degradation state and size range, on the other hand, are relatively shallow with lower average wall slopes, consistent with crater excavation in a weak or poorly cohesive layer. The widespread predominance of these small, shallow craters is consistent with the pervasive, poorly cohesive upper regolith.

Lunar Reconnaissance Orbiter Camera Observations Relating to Science and Landing Site Selection in South Pole-Aitken Basin for a Robotic Sample Return Mission

NASA Technical Reports Server (NTRS)

Jolliff, B. L.; Clegg-Watkins, R. N.; Petro, N. E.; Lawrence, S. L.

2016-01-01

The Moon's South Pole-Aitken basin (SPA) is a high priority target for Solar System exploration, and sample return from SPA is a specific objective in NASA's New Frontiers program. Samples returned from SPA will improve our understanding of early lunar and Solar System events, mainly by placing firm timing constraints on SPA formation and the post-SPA late-heavy bombardment (LHB). Lunar Reconnaissance Orbiter Camera (LROC) images and topographic data, especially Narrow Angle Camera (NAC) scale (1-3 mpp) morphology and digital terrain model (DTM) data are critical for selecting landing sites and assessing landing hazards. Rock components in regolith at a given landing site should include (1) original SPA impact-melt rocks and breccia (to determine the age of the impact event and what materials were incorporated into the melt); (2) impact-melt rocks and breccia from large craters and basins (other than SPA) that represent the post-SPA LHB interval; (3) volcanic basalts derived from the sub-SPA mantle; and (4) older, "cryptomare" (ancient buried volcanics excavated by impact craters, to determine the volcanic history of SPA basin). All of these rock types are sought for sample return. The ancient SPA-derived impact-melt rocks and later-formed melt rocks are needed to determine chronology, and thus address questions of early Solar System dynamics, lunar history, and effects of giant impacts. Surface compositions from remote sensing are consistent with mixtures of SPA impactite and volcanic materials, and near infrared spectral data distinguish areas with variable volcanic contents vs. excavated SPA substrate. Estimating proportions of these rock types in the regolith requires knowledge of the surface deposits, evaluated via morphology, slopes, and terrain ruggedness. These data allow determination of mare-cryptomare-nonmare deposit interfaces in combination with compositional and mineralogical remote sensing to establish the types and relative proportions of materials expected at a given site. Remote sensing compositions, e.g., FeO, also constrain the relative abundances of components. Landing-site assessments use crater and boulder distributions, and slope and terrain rugge

Surveying the Lunar Surface for New Craters with Mini-RF/Goldstone X-Band Bistatic Observations

NASA Astrophysics Data System (ADS)

Cahill, J. T.; Patterson, G.; Turner, F. S.; Morgan, G.; Stickle, A. M.; Speyerer, E. J.; Espiritu, R. C.; Thomson, B. J.

2017-12-01

A multi-look temporal imaging survey by Speyerer et al. (2016) using Lunar Reconnaissance Orbiter Camera (LROC) Narrow Angle Camera (NAC) has highlighted detectable and frequent impact bombardment processes actively modifying the lunar surface. Over 220 new resolvable impacts have been detected since NASA's Lunar Reconnaissance Orbiter (LRO) entered orbit around the Moon, at a flux that is substantially higher than anticipated from previous studies (Neukum et al., 2001). The Miniature Radio Frequency (Mini-RF) instrument aboard LRO is a hybrid dual-polarized synthetic aperture radar (SAR) that now operates in concert with the Arecibo Observatory (AO) and the Goldstone deep space communications complex 34-meter antenna DSS-13 to collect S- and X-band (12.6 and 4.2 cm, respectively) bistatic radar data of the Moon, respectively. Here we targeted some of the larger (>30 m) craters identified by Speyerer et al. (2016) and executed bistatic X-band radar observations both to evaluate our ability to detect and resolve these impact features and further characterize the spatial extent and material size of their ejecta outside optical wavelengths. Data acquired during Mini-RF monostatic operations, when the transmitter was active, show no coverage of the regions in question before or after two of the new impacts occurred. This makes Mini-RF and Earth-based bistatic observations all the more valuable for examination of these fresh new geologic features. Preliminary analyses of Arecibo/Greenbank and Mini-RF/Goldstone observations are unable to resolve the new crater cavities (due to our current resolving capability of 100 m/px), but they further confirm lunar surface roughness changes occurred between 2008 and 2017. Mini-RF X-band observations show newly ejected material was dispersed on the order of 100-300 meters from the point of impact. Scattering observed in the X-band data suggests the presence of rocky ejecta 4 - 45 cm in diameter on the surface and buried to depths of at least 0.5 m.

An Integrated Photogrammetric and Photoclinometric Approach for Pixel-Resolution 3d Modelling of Lunar Surface

NASA Astrophysics Data System (ADS)

Liu, W. C.; Wu, B.

2018-04-01

High-resolution 3D modelling of lunar surface is important for lunar scientific research and exploration missions. Photogrammetry is known for 3D mapping and modelling from a pair of stereo images based on dense image matching. However dense matching may fail in poorly textured areas and in situations when the image pair has large illumination differences. As a result, the actual achievable spatial resolution of the 3D model from photogrammetry is limited by the performance of dense image matching. On the other hand, photoclinometry (i.e., shape from shading) is characterised by its ability to recover pixel-wise surface shapes based on image intensity and imaging conditions such as illumination and viewing directions. More robust shape reconstruction through photoclinometry can be achieved by incorporating images acquired under different illumination conditions (i.e., photometric stereo). Introducing photoclinometry into photogrammetric processing can therefore effectively increase the achievable resolution of the mapping result while maintaining its overall accuracy. This research presents an integrated photogrammetric and photoclinometric approach for pixel-resolution 3D modelling of the lunar surface. First, photoclinometry is interacted with stereo image matching to create robust and spatially well distributed dense conjugate points. Then, based on the 3D point cloud derived from photogrammetric processing of the dense conjugate points, photoclinometry is further introduced to derive the 3D positions of the unmatched points and to refine the final point cloud. The approach is able to produce one 3D point for each image pixel within the overlapping area of the stereo pair so that to obtain pixel-resolution 3D models. Experiments using the Lunar Reconnaissance Orbiter Camera - Narrow Angle Camera (LROC NAC) images show the superior performances of the approach compared with traditional photogrammetric technique. The results and findings from this research contribute to optimal exploitation of image information for high-resolution 3D modelling of the lunar surface, which is of significance for the advancement of lunar and planetary mapping.

Mapping Ejecta Thickness Around Small Lunar Craters

NASA Astrophysics Data System (ADS)

Brunner, A.; Robinson, M. S.

2016-12-01

Detailed knowledge of the distribution of ejecta around small ( 1 km) craters is still a key missing piece in our understanding of crater formation. McGetchin et al. [1] compiled data from lunar, terrestrial, and synthetic craters to generate a semi-empirical model of radial ejecta distribution. Despite the abundance of models, experiments, and previous field and remote sensing studies of this problem, images from the 0.5 m/pixel Lunar Reconnaissance Orbiter Camera (LROC) Narrow Angle Camera (NAC) [2] provides the first chance to quantify the extent and thickness of ejecta around kilometer scale lunar craters. Impacts excavate fresh (brighter) material from below the more weathered (darker) surface, forming a relatively bright ejecta blanket. Over time space weathering tends to lower the reflectance of the ejected fresh material [3] resulting in the fading of albedo signatures around craters. Relatively small impacts that excavate through the high reflectance immature ejecta of larger fresh craters provide the means of estimating ejecta thickness. These subsequent impacts may excavate material from within the high reflectance ejecta layer or from beneath that layer to the lower-reflectance mature pre-impact surface. The reflectance of the ejecta around a subsequent impact allows us to categorize it as either an upper or lower limit on the ejecta thickness at that location. The excavation depth of each crater found in the ejecta blanket is approximated by assuming a depth-to-diameter relationship relevant for lunar simple craters [4, e.g.]. Preliminary results [Figure] show that this technique is valuable for finding the radially averaged profile of the ejecta thickness and that the data are roughly consistent with the McGetchin equation. However, data from craters with asymmetric ejecta blankets are harder to interpret. [1] McGetchin et al. (1973) Earth Planet. Sci. Lett., 20, 226-236. [2] Robinson et al. (2010) Space Sci. Rev., 150, 1-4, 81-124. [3] Denevi et al. (2014) J. Geophys. Res. Planets, 119, 5, 976-997. [4] Wood and Anderson (1978), LPSC IX, 3669-3689.

Calibration of the Lunar Reconnaissance Orbiter Camera

NASA Astrophysics Data System (ADS)

Tschimmel, M.; Robinson, M. S.; Humm, D. C.; Denevi, B. W.; Lawrence, S. J.; Brylow, S.; Ravine, M.; Ghaemi, T.

2008-12-01

The Lunar Reconnaissance Orbiter Camera (LROC) onboard the NASA Lunar Reconnaissance Orbiter (LRO) spacecraft consists of three cameras: the Wide-Angle Camera (WAC) and two identical Narrow Angle Cameras (NAC-L, NAC-R). The WAC is push-frame imager with 5 visible wavelength filters (415 to 680 nm) at a spatial resolution of 100 m/pixel and 2 UV filters (315 and 360 nm) with a resolution of 400 m/pixel. In addition to the multicolor imaging the WAC can operate in monochrome mode to provide a global large- incidence angle basemap and a time-lapse movie of the illumination conditions at both poles. The WAC has a highly linear response, a read noise of 72 e- and a full well capacity of 47,200 e-. The signal-to-noise ratio in each band is 140 in the worst case. There are no out-of-band leaks and the spectral response of each filter is well characterized. Each NAC is a monochrome pushbroom scanner, providing images with a resolution of 50 cm/pixel from a 50-km orbit. A single NAC image has a swath width of 2.5 km and a length of up to 26 km. The NACs are mounted to acquire side-by-side imaging for a combined swath width of 5 km. The NAC is designed to fully characterize future human and robotic landing sites in terms of topography and hazard risks. The North and South poles will be mapped on a 1-meter-scale poleward of 85.5° latitude. Stereo coverage can be provided by pointing the NACs off-nadir. The NACs are also highly linear. Read noise is 71 e- for NAC-L and 74 e- for NAC-R and the full well capacity is 248,500 e- for NAC-L and 262,500 e- for NAC- R. The focal lengths are 699.6 mm for NAC-L and 701.6 mm for NAC-R; the system MTF is 28% for NAC-L and 26% for NAC-R. The signal-to-noise ratio is at least 46 (terminator scene) and can be higher than 200 (high sun scene). Both NACs exhibit a straylight feature, which is caused by out-of-field sources and is of a magnitude of 1-3%. However, as this feature is well understood it can be greatly reduced during ground processing. All three cameras were calibrated in the laboratory under ambient conditions. Future thermal vacuum tests will characterize critical behaviors across the full range of lunar operating temperatures. In-flight tests will check for changes in response after launch and provide key data for meeting the requirements of 1% relative and 10% absolute radiometric calibration.

Controlling High-Resolution LROC NAC Polar Mosaics to LOLA Track Data

NASA Astrophysics Data System (ADS)

Archinal, B.; Lee, E.; Weller, L.; Richie, J.; Edmundson, K.; Laura, J.; Robinson, M.; Speyerer, E.; Boyd, A.; Bowman-Cisneros, E.; Wagner, R.; Nefian, A.

2016-11-01

We describe our progress on completing 1 m resolution geodetically controlled LROC NAC illumination mosaics of both lunar poles out to 85 degrees latitude, constrained using matching to LOLA track data.

Effects of Regolith Properties on UV/VIS Spectra and Implications for Lunar Remote Sensing

NASA Astrophysics Data System (ADS)

Coman, Ecaterina Oana

Lunar regolith chemistry, mineralogy, various maturation factors, and grain size dominate the reflectance of the lunar surface at ultraviolet (UV) to visible (VIS) wavelengths. These regolith properties leave unique fingerprints on reflectance spectra in the form of varied spectral shapes, reflectance intensity values, and absorption bands. With the addition of returned lunar soils from the Apollo and Luna missions as ground truth, these spectral fingerprints can be used to derive maps of global lunar chemistry or mineralogy to analyze the range of basalt types on the Moon, their spatial distribution, and source regions for clues to lunar formation history and evolution. The Lunar Reconnaissance Orbiter Camera (LROC) Wide Angle Camera (WAC) is the first lunar imager to detect bands at UV wavelengths (321 and 360 nm) in addition to visible bands (415, 566, 604, 643, and 689 nm). This dissertation uses a combination of laboratory and remote sensing studies to examine the relation between TiO2 concentration and WAC UV/VIS spectral ratios and to test the effects of variations in lunar chemistry, mineralogy, and soil maturity on ultraviolet and visible wavelength reflectance. Chapter 1 presents an introduction to the dissertation that includes some background in lunar mineralogy and remote sensing. Chapter 2 covers coordinated analyses of returned lunar soils using UV-VIS spectroscopy, X-ray diffraction, and micro X-ray fluorescence. Chapter 3 contains comparisons of local and global remote sensing observations of the Moon using LROC WAC and Clementine UVVIS TiO2 detection algorithms and Lunar Prospector (LP) Gamma Ray Spectrometer (GRS)-derived FeO and TiO2 concentrations. While the data shows effects from maturity and FeO on the UV/VIS detection algorithm, a UV/VIS relationship remains a simple yet accurate method for TiO2 detection on the Moon.

Early LROC Views of Lunar 'Heritage' Sites

NASA Astrophysics Data System (ADS)

Stooke, P. J.

2010-03-01

Early LROC images show some old hardware locations including Apollo and Surveyor sites. The images are used to improve EVA traverse maps and to identify the discarded Surveyor 3 retro-rocket. Future opportunities to observe other items are discussed.

Update on High-Resolution Geodetically Controlled LROC Polar Mosaics

NASA Astrophysics Data System (ADS)

Archinal, B.; Lee, E.; Weller, L.; Richie, J.; Edmundson, K.; Laura, J.; Robinson, M.; Speyerer, E.; Boyd, A.; Bowman-Cisneros, E.; Wagner, R.; Nefian, A.

2015-10-01

We describe progress on high-resolution (1 m/pixel) geodetically controlled LROC mosaics of the lunar poles, which can be used for locating illumination resources (for solar power or cold traps) or landing site and surface operations planning.

Two-Camera Acquisition and Tracking of a Flying Target

NASA Technical Reports Server (NTRS)

Biswas, Abhijit; Assad, Christopher; Kovalik, Joseph M.; Pain, Bedabrata; Wrigley, Chris J.; Twiss, Peter

2008-01-01

A method and apparatus have been developed to solve the problem of automated acquisition and tracking, from a location on the ground, of a luminous moving target in the sky. The method involves the use of two electronic cameras: (1) a stationary camera having a wide field of view, positioned and oriented to image the entire sky; and (2) a camera that has a much narrower field of view (a few degrees wide) and is mounted on a two-axis gimbal. The wide-field-of-view stationary camera is used to initially identify the target against the background sky. So that the approximate position of the target can be determined, pixel locations on the image-detector plane in the stationary camera are calibrated with respect to azimuth and elevation. The approximate target position is used to initially aim the gimballed narrow-field-of-view camera in the approximate direction of the target. Next, the narrow-field-of view camera locks onto the target image, and thereafter the gimbals are actuated as needed to maintain lock and thereby track the target with precision greater than that attainable by use of the stationary camera.

Variable ranking based on the estimated degree of separation for two distributions of data by the length of the receiver operating characteristic curve.

PubMed

Maswadeh, Waleed M; Snyder, A Peter

2015-05-30

Variable responses are fundamental for all experiments, and they can consist of information-rich, redundant, and low signal intensities. A dataset can consist of a collection of variable responses over multiple classes or groups. Usually some of the variables are removed in a dataset that contain very little information. Sometimes all the variables are used in the data analysis phase. It is common practice to discriminate between two distributions of data; however, there is no formal algorithm to arrive at a degree of separation (DS) between two distributions of data. The DS is defined herein as the average of the sum of the areas from the probability density functions (PDFs) of A and B that contain a≥percentage of A and/or B. Thus, DS90 is the average of the sum of the PDF areas of A and B that contain ≥90% of A and/or B. To arrive at a DS value, two synthesized PDFs or very large experimental datasets are required. Experimentally it is common practice to generate relatively small datasets. Therefore, the challenge was to find a statistical parameter that can be used on small datasets to estimate and highly correlate with the DS90 parameter. Established statistical methods include the overlap area of the two data distribution profiles, Welch's t-test, Kolmogorov-Smirnov (K-S) test, Mann-Whitney-Wilcoxon test, and the area under the receiver operating characteristics (ROC) curve (AUC). The area between the ROC curve and diagonal (ACD) and the length of the ROC curve (LROC) are introduced. The established, ACD, and LROC methods were correlated to the DS90 when applied on many pairs of synthesized PDFs. The LROC method provided the best linear correlation with, and estimation of, the DS90. The estimated DS90 from the LROC (DS90-LROC) is applied to a database, as an example, of three Italian wines consisting of thirteen variable responses for variable ranking consideration. An important highlight of the DS90-LROC method is utilizing the LROC curve methodology to test all variables one-at-a-time with all pairs of classes in a dataset. Copyright © 2015 Elsevier B.V. All rights reserved.

Investigations of Water-Bearing Environments on the Moon and Mars

NASA Astrophysics Data System (ADS)

Mitchell, Julie

Water is a critical resource for future human missions, and is necessary for understanding the evolution of the Solar System. The Moon and Mars have water in various forms and are therefore high-priority targets in the search for accessible extraterrestrial water. Complementary remote sensing analyses coupled with laboratory and field studies are necessary to provide a scientific context for future lunar and Mars exploration. In this thesis, I use multiple techniques to investigate the presence of water-ice at the lunar poles and the properties of martian chloride minerals, whose evolution is intricately linked with liquid water. Permanently shadowed regions (PSRs) at the lunar poles may contain substantial water ice, but radar signatures at PSRs could indicate water ice or large block populations. Mini-RF radar and Lunar Reconnaissance Orbiter Camera Narrow Angle Camera (LROC NAC) products were used to assess block abundances where radar signatures indicated potential ice deposits. While the majority of PSRs in this study indicated large block populations and a low likelihood of water ice, one crater--Rozhdestvenskiy N--showed indirect indications of water ice in its interior. Chloride deposits indicate regions where the last substantial liquid water existed on Mars. Major ion abundances and expected precipitation sequences of terrestrial chloride brines could provide context for assessing the provenance of martian chloride deposits. Chloride minerals are most readily distinguished in the far-infrared (45+ microm), where their fundamental absorption features are strongest. Multiple chloride compositions and textures were characterized in far-infrared emission for the first time. Systematic variations in the spectra were observed; these variations will allow chloride mineralogy to be determined and large variations in texture to be constrained. In the present day, recurring slope lineae (RSL) may indicate water flow, but fresh water is not stable on Mars. However, dissolved chloride could allow liquid water to flow transiently. Using Thermal Emission Imaging System (THEMIS) data, I determined that RSL are most likely not fed by chloride-rich brines on Mars. Substantial amounts of salt would be consumed to produce a surface water flow; therefore, these features are therefore thought to instead be surface darkening due to capillary wicking.

Breaking Ground on the Moon and Mars: Reconstructing Lunar Tectonic Evolution and Martian Central Pit Crater Formation

NASA Astrophysics Data System (ADS)

Williams, Nathan Robert

Understanding the structural evolution of planetary surfaces provides key insights to their physical properties and processes. On the Moon, large-scale tectonism was thought to have ended over a billion years ago. However, new Lunar Reconnaissance Orbiter Camera (LROC) Narrow Angle Camera (NAC) high resolution images show the Moon's surface in unprecedented detail and show many previously unidentified tectonic landforms, forcing a re-assessment of our views of lunar tectonism. I mapped lobate scarps, wrinkle ridges, and graben across Mare Frigoris -- selected as a type area due to its excellent imaging conditions, abundance of tectonic landforms, and range of inferred structural controls. The distribution, morphology, and crosscutting relationships of these newly identified populations of tectonic landforms imply a more complex and longer-lasting history of deformation that continues to today. I also performed additional numerical modeling of lobate scarp structures that indicates the upper kilometer of the lunar surface has experienced 3.5-18.6 MPa of differential stress in the recent past, likely due to global compression from radial thermal contraction. Central pit craters on Mars are another instance of intriguing structures that probe subsurface physical properties. These kilometer-scale pits are nested in the centers of many impact craters on Mars as well as on icy satellites. They are inferred to form in the presence of a water-ice rich substrate; however, the process(es) responsible for their formation is still debated. Previous models invoke origins by either explosive excavation of potentially water-bearing crustal material, or by subsurface drainage of meltwater and/or collapse. I assessed radial trends in grain size around central pits using thermal inertias calculated from Thermal Emission Imaging System (THEMIS) thermal infrared images. Average grain size decreases with radial distance from pit rims -- consistent with pit-derived ejecta but not expected for collapse models. I present a melt-contact model that might enable a delayed explosion, in which a central uplift brings ice-bearing substrate into contact with impact melt to generate steam explosions and excavate central pits during the impact modification stage.

Geomorphological Analysis of Lunar Swirls: Insights from LROC-NAC

NASA Astrophysics Data System (ADS)

Jozwiak, L. M.; Blewett, D. T.

2017-12-01

The enigmatic features known as lunar swirls are a set of high-reflectance, sinuous features observed in both mare and highland settings, and often associated with crustal magnetic anomalies. There are several hypotheses for the formation of swirls, including atypical space weathering resulting from solar wind stand-off, disruption of regolith structure and imposition of a magnetic field associated with recent cometary impacts, and levitation and magnetic sorting of fine-grained dust. Investigations utilizing data from Diviner and Mini-RF suggest that, at the scales sensed by the instruments, regolith in swirl regions is indistinguishable from regolith in non-swirl regions. We have used data from the LRO Camera-Narrow Angle Camera to study the structure of lunar swirls, and explore whether the high-reflectance material associated with lunar swirls represents a discrete deposit. We assessed the populations of impact craters with diameter greater than 1 km on the Reiner Gamma swirl and on a nearby region of lunar mare located on the same lava flow unit, and determined that the crater populations suggest that the presence of the swirl does not affect the background impact crater population. We also investigated whether small (D < 0.5 km) superposed impact craters showed evidence for excavation of material from beneath a hypothetical surficial swirl deposit. Investigating the swirls located at Reiner Gamma, Mare Ingenii, Mare Marginis, and the crater Gerasimovich and adjacent non-swirl regions, we observed high-reflectance ejecta deposits whose morphology and degradation are consistent with space weathering processes. We further observe the relative proportion of these high-reflectance excavations to be greater in the swirl regions, suggesting a qualitatively slower space weathering process in these regions. In all regions, we also observed the excavation of low-reflectance material distributed in the ejecta deposit of superposed craters with a wide range of diameters, and a wide range of distribution patterns. We also observe these dark materials in non-swirl regions, suggesting they are not unique to the swirl environment. Our investigations are consistent with the atypical space weathering hypothesis.

Ten-Meter Scale Topography and Roughness of Mars Exploration Rovers Landing Sites and Martian Polar Regions

NASA Technical Reports Server (NTRS)

Ivanov, Anton B.

2003-01-01

The Mars Orbiter Camera (MOC) has been operating on board of the Mars Global Surveyor (MGS) spacecraft since 1998. It consists of three cameras - Red and Blue Wide Angle cameras (FOV=140 deg.) and Narrow Angle camera (FOV=0.44 deg.). The Wide Angle camera allows surface resolution down to 230 m/pixel and the Narrow Angle camera - down to 1.5 m/pixel. This work is a continuation of the project, which we have reported previously. Since then we have refined and improved our stereo correlation algorithm and have processed many more stereo pairs. We will discuss results of our stereo pair analysis located in the Mars Exploration rovers (MER) landing sites and address feasibility of recovering topography from stereo pairs (especially in the polar regions), taken during MGS 'Relay-16' mode.

The emplacement of long lava flows in Mare Imbrium, the Moon

NASA Astrophysics Data System (ADS)

Garry, W. B.

2012-12-01

Lava flow margins are scarce on the lunar surface. The best developed lava flows on the Moon occur in Mare Imbrium where flow margins are traceable nearly their entire flow length. The flow field originates in the southwest part of the basin from a fissure or series of fissures and cones located in the vicinity of Euler crater and erupted in three phases (Phases I, II, III) over a period of 0.5 Billion years (3.0 - 2.5 Ga). The flow field was originally mapped with Apollo and Lunar Orbiter data by Schaber (1973) and shows the flow field extends 200 to 1200 km from the presumed source area and covers an area of 2.0 x 10^5 km^2 with an estimated eruptive volume of 4 x 10^4 km^3. Phase I flows extend 1200 km and have the largest flow volume, but interestingly do not exhibit visible topography and are instead defined by difference in color from the surrounding mare flows. Phases II and III flows have well-defined flow margins (10 - 65 m thick) and channels (0.4 - 2.0 km wide, 40 - 70 m deep), but shorter flow lengths, 600 km and 400 km respectively. Recent missions, including Lunar Reconnaissance Orbiter (LRO), Kaguya (Selene), and Clementine, provide high resolution data sets of these lava flows. Using a combination of data sets including images from LRO Wide-Angle-Camera (WAC)(50-100 m/pixel) and Narrow-Angle-Camera (NAC) (up to 0.5m/pixel), Kaguya Terrain Camera (TC) (10 m/pixel), and topography from LRO Lunar Orbiter Laser Altimeter (LOLA), the morphology has been remapped and topographic measurements of the flow features have been made in an effort to reevaluate the emplacement of the flow field. Morphologic mapping reveals a different flow path for Phase I compared to the original mapping completed by Schaber (1973). The boundaries of the Phase I flow field have been revised based on Moon Mineralogy Mapper color ratio images (Staid et al., 2011). This has implications for the area covered and volume erupted during this stage, as well as, the age of Phase I. Flow features and margins have been identified in the Phase I flow within the LROC WAC mosaic and in Narrow Angle Camera (NAC) images. These areas have a mottled appearance. LOLA profiles over the more prominent flow lobes in Phase I reveal these margins are less 10 m thick. Phase II and III morphology maps are similar to previous flow maps. Phase III lobes near Euler are 10-12 km wide and 20-30 m thick based on measurements of the LOLA 1024ppd Elevation Digital Terrain Model (DTM) in JMoon. One of the longer Phase III lobes varies between 15 to 50 km wide and 25 to 60 m thick, with the thickest section at the distal end of the lobe. The Phase II lobe is 15 to 25 m thick and up to 35 km wide. The eruptive volume of the Mare Imbrium lava flows has been compared to terrestrial flood basalts. The morphology of the lobes in Phase II and III, which includes levees, thick flow fronts, and lobate margins suggests these could be similar to terrestrial aa-style flows. The Phase I flows might be more representative of sheet flows, pahoehoe-style flows, or inflated flows. Morphologic comparisons will be made with terrestrial flows at Askja volcano in Iceland, a potential analog to compare different styles of emplacement for the flows in Mare Imbrium.

ARC-1986-A86-7011

NASA Image and Video Library

1986-01-14

Range : 2.52 million miles (1.56 million miles) P-29481B/W Voyager 2 returned this photograph with all nine known Uranus rings visible from a 15 sec. exposure through the narrow angle camera. The rings are quite dark and very narrow. The most prominent and outermost of the nine, Epsilon, is seen at top. The next three in toward Uranus, called Delta, Gamma, and Eta, are much fainter and more narrow than Epsilon ring. Then come Beta and Alpha rings, and finally, the innermost grouping, known simply as the 4,5, & 6 rings. The last three are very faint and are at the limit of detection for the Voyager camera. Uranus' rings range in width from about 100 km. (60 mi.) at the widest part of the Epsilon ring, to only a few kilometers for most of the others. this iamge was processed to enhance narrow features; the bright dots are imperfections on the camera detector. The resolution scale is about 50 km. (30 mi.)

Evaluation of Multiclass Model Observers in PET LROC Studies

NASA Astrophysics Data System (ADS)

Gifford, H. C.; Kinahan, P. E.; Lartizien, C.; King, M. A.

2007-02-01

A localization ROC (LROC) study was conducted to evaluate nonprewhitening matched-filter (NPW) and channelized NPW (CNPW) versions of a multiclass model observer as predictors of human tumor-detection performance with PET images. Target localization is explicitly performed by these model observers. Tumors were placed in the liver, lungs, and background soft tissue of a mathematical phantom, and the data simulation modeled a full-3D acquisition mode. Reconstructions were performed with the FORE+AWOSEM algorithm. The LROC study measured observer performance with 2D images consisting of either coronal, sagittal, or transverse views of the same set of cases. Versions of the CNPW observer based on two previously published difference-of-Gaussian channel models demonstrated good quantitative agreement with human observers. One interpretation of these results treats the CNPW observer as a channelized Hotelling observer with implicit internal noise

Characterisation of potential landing sites for the European Space Agency's Lunar Lander project

NASA Astrophysics Data System (ADS)

De Rosa, Diego; Bussey, Ben; Cahill, Joshua T.; Lutz, Tobias; Crawford, Ian A.; Hackwill, Terence; van Gasselt, Stephan; Neukum, Gerhard; Witte, Lars; McGovern, Andy; Grindrod, Peter M.; Carpenter, James D.

2012-12-01

This article describes the characterisation activities of the landing sites currently envisaged for the Lunar Lander mission of the European Space Agency. These sites have been identified in the South Pole Region (-85° to-90° latitude) based on favourable illumination conditions, which make it possible to have a long-duration mission with conventional power and thermal control subsystems, capable of enduring relatively short periods of darkness (in the order of tens of hours), instead of utilising Radioisotope Heating Units. The illumination conditions are simulated at the potential landing sites based on topographic data from the Lunar Orbiter Laser Altimeter (LOLA), using three independent tools. Risk assessment of the identified sites is also being performed through independent studies. Long baseline slopes are assessed based on LOLA, while craters and boulders are detected both visually and using computer tools in Lunar Reconnaissance Orbiter Camera (LROC) images, down to a size of less than 2 m, and size-frequency distributions are generated. Shadow hazards are also assessed via LROC images. The preliminary results show that areas with quasi-continuous illumination of several months exist, but their size is small (few hundred metres); the duration of the illumination period drops quickly to less than one month outside the areas, and some areas present gaps with short illumination periods. Concerning hazard distributions, 50 m slopes are found to be shallow (few degrees) based on LOLA, whereas at the scale of the lander footprint (˜5 m) they are mostly dominated by craters, expected to be mature (from geological context) and shallow (˜11°). The preliminary conclusion is that the environment at the prospective landing sites is within the capabilities of the Lander design.

HIGH SPEED CAMERA

DOEpatents

Rogers, B.T. Jr.; Davis, W.C.

1957-12-17

This patent relates to high speed cameras having resolution times of less than one-tenth microseconds suitable for filming distinct sequences of a very fast event such as an explosion. This camera consists of a rotating mirror with reflecting surfaces on both sides, a narrow mirror acting as a slit in a focal plane shutter, various other mirror and lens systems as well as an innage recording surface. The combination of the rotating mirrors and the slit mirror causes discrete, narrow, separate pictures to fall upon the film plane, thereby forming a moving image increment of the photographed event. Placing a reflecting surface on each side of the rotating mirror cancels the image velocity that one side of the rotating mirror would impart, so as a camera having this short a resolution time is thereby possible.

Revisiting the Field Geology of Taurus-Littrow

NASA Technical Reports Server (NTRS)

Schmitt, H. H.; Petro, N. E.; Wells, R. A.; Robinson, M. S.; Weiss, B. P.; Mercer, C. M.

2016-01-01

Integration of Apollo 17 field observations and photographs, sample investigations, Lunar Reconnaissance Orbiter Camera images, Chandrayaan-1 Moon Mineralogy Mapper (M(sup 3)) spectra, and Miniature Radio Frequency (Mini-RF) S-band radar images provides new insights into the geology of the valley of Taurus-Littrow on the Moon. Connecting the various remote observations to sample data enables a set of new conclusions to be drawn regarding the geological evolution of the valley. Structural considerations and published and recalculated Ar-40/Ar-39 analyses of samples from the North Massif and the Sculptured Hills indicate that the Crisium basin formed about 3.93 Ga; the Serenitatis basin about 3.82 Ga; and the Imbrium basin no earlier than 3.82 Ga and no later than the average of 3.72 Ga for 33 age dates from samples of the valley's mare basalts. Strong evidence continues to support the conclusion of others (Lucchitta, 1972; Spudis et al., 2011; Fassett et al., 2012) that the Sculptured Hills physiographic unit consists of Imbrium ejecta. Interpretation of M(sup 3) spectral data and Apollo 17 samples indicate that rock units of the Sculptured Hills consist of a largely coherent, Mg-suite pluton. LROC NAC stereo images and Mini-RF data indicate the presence of several exposed pyroclastic fissures across the Sculptured Hills. Rim boulders at Camelot Crater constitute nearly in situ wall rocks of that crater rather than ejecta and provide an opportunity for investigations of remanent magnetic field orientation at the time of the eruption of late mare basalt lavas in the valley. Paleomagnetic field orientation information also may be obtained relative to melt-breccia contacts in North Massif boulders that suggest original horizontal orientations. LROC images indicate the existence of two temporally separate light mantle avalanche deposits. The origin, potential flow mechanisms, and geology of the youngest avalanche from the South Massif have been clarified. The existence of two distinct light mantle avalanches raises doubt about the association of either light mantle avalanche with secondary impacts related to the Tycho impact event. Alternatively, the Lee-Lincoln thrust fault appears to have triggered the second light mantle avalanche between 70 and 110 Ma. A simple structural analysis shows that this thrust fault dips 20-25 degrees to the southwest where it crosses the North Massif and to the west where it crosses the valley floor. Mini-RF data reveal a line of reduced reflections roughly perpendicular to contours on the North Massif about 3 km to the east of the Lee-Lincoln fault. Although this line is possibly an older ancillary fault, LROC NAC stereo images indicate that it may be best explained as a pyroclastic fissure. A debris flow of dark, apparent pyroclastic ash lies below the southeast end of the potential fissure. Finally, young lunar impact glass sample 70019 has been precisely located within LROC NAC images and oriented for the first time using 60 mm (f.l.) sample documentation photographs. Sample 70019 can now be employed in lunar paleomagnetic field orientation studies.

Revisiting the field geology of Taurus-Littrow

NASA Astrophysics Data System (ADS)

Schmitt, H. H.; Petro, N. E.; Wells, R. A.; Robinson, M. S.; Weiss, B. P.; Mercer, C. M.

2017-12-01

Integration of Apollo 17 field observations and photographs, sample investigations, Lunar Reconnaissance Orbiter Camera images, Chandrayaan-1 Moon Mineralogy Mapper (M3) spectra, and Miniature Radio Frequency (Mini-RF) S-band radar images provides new insights into the geology of the valley of Taurus-Littrow on the Moon. Connecting the various remote observations to sample data enables a set of new conclusions to be drawn regarding the geological evolution of the valley. Structural considerations and published and recalculated 40Ar/39Ar analyses of samples from the North Massif and the Sculptured Hills indicate that the Crisium basin formed about 3.93 Ga; the Serenitatis basin about 3.82 Ga; and the Imbrium basin no earlier than 3.82 Ga and no later than the average of 3.72 Ga for 33 age dates from samples of the valley's mare basalts. Strong evidence continues to support the conclusion of others (Lucchitta, 1972; Spudis et al., 2011; Fassett et al., 2012) that the Sculptured Hills physiographic unit consists of Imbrium ejecta. Interpretation of M3 spectral data and Apollo 17 samples indicate that rock units of the Sculptured Hills consist of a largely coherent, Mg-suite pluton. LROC NAC stereo images and Mini-RF data indicate the presence of several exposed pyroclastic fissures across the Sculptured Hills. Rim boulders at Camelot Crater constitute nearly in situ wall rocks of that crater rather than ejecta and provide an opportunity for investigations of remanent magnetic field orientation at the time of the eruption of late mare basalt lavas in the valley. Paleomagnetic field orientation information also may be obtained relative to melt-breccia contacts in North Massif boulders that suggest original horizontal orientations. LROC images indicate the existence of two temporally separate light mantle avalanche deposits. The origin, potential flow mechanisms, and geology of the youngest avalanche from the South Massif have been clarified. The existence of two distinct light mantle avalanches raises doubt about the association of either light mantle avalanche with secondary impacts related to the Tycho impact event. Alternatively, the Lee-Lincoln thrust fault appears to have triggered the second light mantle avalanche between 70 and 110 Ma. A simple structural analysis shows that this thrust fault dips 20-25° to the southwest where it crosses the North Massif and to the west where it crosses the valley floor. Mini-RF data reveal a line of reduced reflections roughly perpendicular to contours on the North Massif about 3 km to the east of the Lee-Lincoln fault. Although this line is possibly an older ancillary fault, LROC NAC stereo images indicate that it may be best explained as a pyroclastic fissure. A debris flow of dark, apparent pyroclastic ash lies below the southeast end of the potential fissure. Finally, young lunar impact glass sample 70019 has been precisely located within LROC NAC images and oriented for the first time using 60 mm (f.l.) sample documentation photographs. Sample 70019 can now be employed in lunar paleomagnetic field orientation studies.

Physical properties of lunar craters

NASA Astrophysics Data System (ADS)

Joshi, Maitri P.; Bhatt, Kushal P.; Jain, Rajmal

2017-02-01

The surface of the Moon is highly cratered due to impacts of meteorites, asteroids, comets and other celestial objects. The origin, size, structure, age and composition vary among craters. We study a total of 339 craters observed by the Lunar Reconnaissance Orbiter Camera (LROC). Out of these 339 craters, 214 craters are known (named craters included in the IAU Gazetteer of Planetary Nomenclature) and 125 craters are unknown (craters that are not named and objects that are absent in the IAU Gazetteer). We employ images taken by LROC at the North and South Poles and near side of the Moon. We report for the first time the study of unknown craters, while we also review the study of known craters conducted earlier by previous researchers. Our study is focused on measurements of diameter, depth, latitude and longitude of each crater for both known and unknown craters. The diameter measurements are based on considering the Moon to be a spherical body. The LROC website also provides a plot which enables us to measure the depth and diameter. We found that out of 214 known craters, 161 craters follow a linear relationship between depth (d) and diameter (D), but 53 craters do not follow this linear relationship. We study physical dimensions of these 53 craters and found that either the depth does not change significantly with diameter or the depths are extremely high relative to diameter (conical). Similarly, out of 125 unknown craters, 78 craters follow the linear relationship between depth (d) and diameter (D) but 47 craters do not follow the linear relationship. We propose that the craters following the scaling law of depth and diameter, also popularly known as the linear relationship between d and D, are formed by the impact of meteorites having heavy metals with larger dimension, while those with larger diameter but less depth are formed by meteorites/celestial objects having low density material but larger diameter. The craters with very high depth and with very small diameter are perhaps formed by the impact of meteorites that have very high density but small diameter with a conical shape. Based on analysis of the data selected for the current investigation, we further found that out of 339 craters, 100 (29.5%) craters exist near the equator, 131 (38.6%) are in the northern hemisphere and 108 (31.80%) are in the southern hemisphere. This suggests the Moon is heavily cratered at higher latitudes and near the equatorial zone.

The Widespread Distribution of Swirls in Lunar Reconnaissance Orbiter Camera Images

NASA Astrophysics Data System (ADS)

Denevi, B. W.; Robinson, M. S.; Boyd, A. K.; Blewett, D. T.

2015-10-01

Lunar swirls, the sinuous high-and low-reflectance features that cannot be mentioned without the associated adjective "enigmatic,"are of interest because of their link to crustal magnetic anomalies [1,2]. These localized magnetic anomalies create mini-magnetospheres [3,4] and may alter the typical surface modification processes or result in altogether distinct processes that form the swirls. One hypothesis is that magnetic anomalies may provide some degree of shielding from the solar wind [1,2], which could impede space weathering due to solar wind sputtering. In this case, swirls would serve as a way to compare areas affected by typical lunar space weathering (solar wind plus micrometeoroid bombardment) to those where space weathering is dominated by micrometeoroid bombardment alone, providing a natural means to assess the relative contributions of these two processes to the alteration of fresh regolith. Alternately,magnetic anomalies may play a role in the sorting of soil grains, such that the high-reflectance portion of swirls may preferentially accumulate feldspar-rich dust [5]or soils with a lower component of nanophase iron [6].Each of these scenarios presumes a pre-existing magnetic anomaly; swirlshave also been suggested to be the result of recent cometary impacts in which the remanent magnetic field is generated by the impact event[7].Here we map the distribution of swirls using ultraviolet and visible images from the Lunar Reconnaissance Orbiter Camera(LROC) Wide Angle Camera (WAC) [8,9]. We explore the relationship of the swirls to crustal magnetic anomalies[10], and examine regions with magnetic anomalies and no swirls.

CMOS image sensor with organic photoconductive layer having narrow absorption band and proposal of stack type solid-state image sensors

NASA Astrophysics Data System (ADS)

Takada, Shunji; Ihama, Mikio; Inuiya, Masafumi

2006-02-01

Digital still cameras overtook film cameras in Japanese market in 2000 in terms of sales volume owing to their versatile functions. However, the image-capturing capabilities such as sensitivity and latitude of color films are still superior to those of digital image sensors. In this paper, we attribute the cause for the high performance of color films to their multi-layered structure, and propose the solid-state image sensors with stacked organic photoconductive layers having narrow absorption bands on CMOS read-out circuits.

LRO Finds Apollo 16 Booster Rocket Impact Site

NASA Image and Video Library

2017-12-08

After decades of uncertainty, the Apollo 16 S-IVB impact site on the lunar surface has been identified. S-IVBs were portions of the Saturn V rockets that brought astronauts to the moon. The site was identified in imagery from the high-resolution LROC Narrow Angle Camera aboard NASA's Lunar Reconnaissance Orbiter. Beginning with Apollo 13, the S-IVB rocket stages were deliberately impacted on the lunar surface after they were used. Seismometers placed on the moon by earlier Apollo astronauts measured the energy of these impacts to shed light on the internal lunar structure. Locations of the craters that the boosters left behind were estimated from tracking data collected just prior to the impacts. Earlier in the LRO mission, the Apollo 13, 14, 15 and 17 impact sites were successfully identified, but Apollo 16's remained elusive. In the case of Apollo 16, radio contact with the booster was lost before the impact, so the location was only poorly known. Positive identification of the Apollo 16 S-IVB site took more time than the other four impact craters because the location ended up differing by about 30 km (about 19 miles) from the Apollo-era tracking estimate. (For comparison, the other four S-IVB craters were all within 7 km -- about four miles -- of their estimated locations.) Apollo 16's S-IVB stage is on Mare Insularum, about 160 miles southwest of Copernicus Crater (more precisely: 1.921 degrees north, 335.377 degrees east, minus 1,104 meters elevation). Credit: NASA/Goddard/Arizona State University NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

Assessment of cardiac single-photon emission computed tomography performance using a scanning linear observer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lee, Chih-Jie; Kupinski, Matthew A.; Volokh, Lana

2013-01-15

Purpose: Single-photon emission computed tomography (SPECT) is widely used to detect myocardial ischemia and myocardial infarction. It is important to assess and compare different SPECT system designs in order to achieve the highest detectability of cardiac defects. Methods: Whitaker et al.'s study ['Estimating random signal parameters from noisy images with nuisance parameters: linear and scanning-linear methods,' Opt. Express 16(11), 8150-8173 (2008)] on the scanning linear observer (SLO) shows that the SLO can be used to estimate the location and size of signals. One major advantage of the SLO is that it can be used with projection data rather than withmore » reconstruction data. Thus, this observer model assesses the overall hardware performance independent of any reconstruction algorithm. In addition, the computation time of image quality studies is significantly reduced. In this study, three systems based on the design of the GE cadmium zinc telluride-based dedicated cardiac SPECT camera Discovery 530c were assessed. This design, which is officially named the Alcyone Technology: Discovery NM 530c, was commercialized in August, 2009. The three systems, GE27, GE19, and GE13, contain 27, 19, and 13 detectors, respectively. Clinically, a human heart can be virtually segmented into three coronary artery territories: the left-anterior descending artery, left-circumflex artery, and right coronary artery. One of the most important functions of a cardiac SPECT system is to produce images from which a radiologist can accurately predict in which territory the defect exists [http://www.asnc.org/media/PDFs/PPReporting081511.pdf, Guideline from American Society of Nuclear Cardiology]. A good estimation of the extent of the defect from the projection images is also very helpful for determining the seriousness of the myocardial ischemia. In this study, both the location and extent of defects were estimated by the SLO, and the system performance was assessed by localization receiver operating characteristic (LROC) [P. Khurd and G. Gindi, 'Decision strategies maximizing the area under the LROC curve,' Proc. SPIE 5749, 150-161 (2005)] or estimation receiver operating characteristic (EROC) [E. Clarkson, 'Estimation receiver operating characteristic curve and ideal observers for combined detection/estimation tasks,' J. Opt. Soc. Am. A 24, B91-B98 (2007)] curves. Results: The area under the LROC/EROC curve (AULC/AUEC) and the true positive fraction (TPF) at a specific false positive fraction (FPF) can be treated as the figures of merit. For radii estimation with a 1 mm tolerance, the AUEC values of the GE27, GE19, and GE13 systems are 0.8545, 0.8488, and 0.8329, and the TPF at FPF = 5% are 77.1%, 76.46%, and 73.55%, respectively. The assessment of all three systems revealed that the GE19 system yields estimated information and cardiac defect detectability very close to those of the GE27 system while using eight fewer detectors. Thus, 30% of the expensive detector units can be removed with confidence. Conclusions: As the results show, a combination of the SLO and LROC/EROC curves can determine the configuration that yields the most relevant estimation/detection information. Thus, this is a useful method for assessing cardiac SPECT systems.« less

Pinhole Cameras: For Science, Art, and Fun!

ERIC Educational Resources Information Center

Button, Clare

2007-01-01

A pinhole camera is a camera without a lens. A tiny hole replaces the lens, and light is allowed to come in for short amount of time by means of a hand-operated shutter. The pinhole allows only a very narrow beam of light to enter, which reduces confusion due to scattered light on the film. This results in an image that is focused, reversed, and…

Depth of maturity in the Moon's regolith

NASA Astrophysics Data System (ADS)

Denevi, B. W.; Duck, A.; Klem, S.; Ravi, S.; Robinson, M. S.; Speyerer, E. J.

2017-12-01

The observed maturity of the lunar surface is a function of its exposure to the weathering agents of the space environment as well as the rates of regolith gardening and overturn. Regolith exposed on the surface weathers until it is buried below material delivered to the surface by impact events; weathering resumes when it is re-exposed to the surface environment by later impacts. This cycle repeats until a mature layer of some thickness develops. The gardening rate of the upper regolith has recently been shown to be substantially higher than previously thought, and new insights on the rates of space weathering and potential variation of these rates with solar wind flux have been gained from remote sensing as well as laboratory studies. Examining the depth to which the lunar regolith is mature across a variety of locations on the Moon can provide new insight into both gardening and space weathering. Here we use images from the Lunar Reconnaissance Orbiter Camera (LROC) with pixel scales less than approximately 50 cm to examine the morphology and reflectance of impact craters in the 2- to 100-m diameter size range. Apollo core samples show substantial variation, but suggest that the upper 50 cm to >1 m of regolith is mature at the sampled sites. These depths indicate that because craters excavate to a maximum depth of 10% of the transient crater diameter, craters with diameters less than 5-10 m will typically expose only mature material and this phenomenon should be observable in LROC images. Thus, we present the results of classifying craters by both morphology and reflectance to determine the size-frequency distribution of craters that expose immature material versus those that do not. These results are then compared to observations of reflectance values for the ejecta of craters that have formed during the LRO mission. These newly formed craters span a similar range of diameters, and there is no ambiguity about post-impact weathering because they are less than a decade old.

The first demonstration of the concept of "narrow-FOV Si/CdTe semiconductor Compton camera"

NASA Astrophysics Data System (ADS)

Ichinohe, Yuto; Uchida, Yuusuke; Watanabe, Shin; Edahiro, Ikumi; Hayashi, Katsuhiro; Kawano, Takafumi; Ohno, Masanori; Ohta, Masayuki; Takeda, Shin`ichiro; Fukazawa, Yasushi; Katsuragawa, Miho; Nakazawa, Kazuhiro; Odaka, Hirokazu; Tajima, Hiroyasu; Takahashi, Hiromitsu; Takahashi, Tadayuki; Yuasa, Takayuki

2016-01-01

The Soft Gamma-ray Detector (SGD), to be deployed on board the ASTRO-H satellite, has been developed to provide the highest sensitivity observations of celestial sources in the energy band of 60-600 keV by employing a detector concept which uses a Compton camera whose field-of-view is restricted by a BGO shield to a few degree (narrow-FOV Compton camera). In this concept, the background from outside the FOV can be heavily suppressed by constraining the incident direction of the gamma ray reconstructed by the Compton camera to be consistent with the narrow FOV. We, for the first time, demonstrate the validity of the concept using background data taken during the thermal vacuum test and the low-temperature environment test of the flight model of SGD on ground. We show that the measured background level is suppressed to less than 10% by combining the event rejection using the anti-coincidence trigger of the active BGO shield and by using Compton event reconstruction techniques. More than 75% of the signals from the field-of-view are retained against the background rejection, which clearly demonstrates the improvement of signal-to-noise ratio. The estimated effective area of 22.8 cm2 meets the mission requirement even though not all of the operational parameters of the instrument have been fully optimized yet.

Quantitative analysis of the improvement in omnidirectional maritime surveillance and tracking due to real-time image enhancement

NASA Astrophysics Data System (ADS)

de Villiers, Jason P.; Bachoo, Asheer K.; Nicolls, Fred C.; le Roux, Francois P. J.

2011-05-01

Tracking targets in a panoramic image is in many senses the inverse problem of tracking targets with a narrow field of view camera on a pan-tilt pedestal. In a narrow field of view camera tracking a moving target, the object is constant and the background is changing. A panoramic camera is able to model the entire scene, or background, and those areas it cannot model well are the potential targets and typically subtended far fewer pixels in the panoramic view compared to the narrow field of view. The outputs of an outward staring array of calibrated machine vision cameras are stitched into a single omnidirectional panorama and used to observe False Bay near Simon's Town, South Africa. A ground truth data-set was created by geo-aligning the camera array and placing a differential global position system receiver on a small target boat thus allowing its position in the array's field of view to be determined. Common tracking techniques including level-sets, Kalman filters and particle filters were implemented to run on the central processing unit of the tracking computer. Image enhancement techniques including multi-scale tone mapping, interpolated local histogram equalisation and several sharpening techniques were implemented on the graphics processing unit. An objective measurement of each tracking algorithm's robustness in the presence of sea-glint, low contrast visibility and sea clutter - such as white caps is performed on the raw recorded video data. These results are then compared to those obtained with the enhanced video data.

Fisheye Multi-Camera System Calibration for Surveying Narrow and Complex Architectures

NASA Astrophysics Data System (ADS)

Perfetti, L.; Polari, C.; Fassi, F.

2018-05-01

Narrow spaces and passages are not a rare encounter in cultural heritage, the shape and extension of those areas place a serious challenge on any techniques one may choose to survey their 3D geometry. Especially on techniques that make use of stationary instrumentation like terrestrial laser scanning. The ratio between space extension and cross section width of many corridors and staircases can easily lead to distortions/drift of the 3D reconstruction because of the problem of propagation of uncertainty. This paper investigates the use of fisheye photogrammetry to produce the 3D reconstruction of such spaces and presents some tests to contain the degree of freedom of the photogrammetric network, thereby containing the drift of long data set as well. The idea is that of employing a multi-camera system composed of several fisheye cameras and to implement distances and relative orientation constraints, as well as the pre-calibration of the internal parameters for each camera, within the bundle adjustment. For the beginning of this investigation, we used the NCTech iSTAR panoramic camera as a rigid multi-camera system. The case study of the Amedeo Spire of the Milan Cathedral, that encloses a spiral staircase, is the stage for all the tests. Comparisons have been made between the results obtained with the multi-camera configuration, the auto-stitched equirectangular images and a data set obtained with a monocular fisheye configuration using a full frame DSLR. Results show improved accuracy, down to millimetres, using a rigidly constrained multi-camera.

An improved camera trap for amphibians, reptiles, small mammals, and large invertebrates

USGS Publications Warehouse

Hobbs, Michael T.; Brehme, Cheryl S.

2017-01-01

Camera traps are valuable sampling tools commonly used to inventory and monitor wildlife communities but are challenged to reliably sample small animals. We introduce a novel active camera trap system enabling the reliable and efficient use of wildlife cameras for sampling small animals, particularly reptiles, amphibians, small mammals and large invertebrates. It surpasses the detection ability of commonly used passive infrared (PIR) cameras for this application and eliminates problems such as high rates of false triggers and high variability in detection rates among cameras and study locations. Our system, which employs a HALT trigger, is capable of coupling to digital PIR cameras and is designed for detecting small animals traversing small tunnels, narrow trails, small clearings and along walls or drift fencing.

An improved camera trap for amphibians, reptiles, small mammals, and large invertebrates.

PubMed

Hobbs, Michael T; Brehme, Cheryl S

2017-01-01

Camera traps are valuable sampling tools commonly used to inventory and monitor wildlife communities but are challenged to reliably sample small animals. We introduce a novel active camera trap system enabling the reliable and efficient use of wildlife cameras for sampling small animals, particularly reptiles, amphibians, small mammals and large invertebrates. It surpasses the detection ability of commonly used passive infrared (PIR) cameras for this application and eliminates problems such as high rates of false triggers and high variability in detection rates among cameras and study locations. Our system, which employs a HALT trigger, is capable of coupling to digital PIR cameras and is designed for detecting small animals traversing small tunnels, narrow trails, small clearings and along walls or drift fencing.

ARC-1986-A86-7024

NASA Image and Video Library

1986-01-24

P-29508BW Range: 1.12 million kilometers (690,000 miles) This clear-filter view of the Uranian rings delta, gamma, eta, beta and alpha (from top) was taken with Voyager 2's narrow-angle camera and clearly illustrates the broad outer component and narrow inner component of the eta ring, which orbits Uranus at a radius of some 47,000 km (29,000 mi). The broad component is considerably more transparent than the dense, narrow inner eta component, as well as the other narrow rings shown. Resolution here is about 10 km (6 mi).

Voyager spacecraft images of Jupiter and Saturn

NASA Technical Reports Server (NTRS)

Birnbaum, M. M.

1982-01-01

The Voyager imaging system is described, noting that it is made up of a narrow-angle and a wide-angle TV camera, each in turn consisting of optics, a filter wheel and shutter assembly, a vidicon tube, and an electronics subsystem. The narrow-angle camera has a focal length of 1500 mm; its field of view is 0.42 deg and its focal ratio is f/8.5. For the wide-angle camera, the focal length is 200 mm, the field of view 3.2 deg, and the focal ratio of f/3.5. Images are exposed by each camera through one of eight filters in the filter wheel on the photoconductive surface of a magnetically focused and deflected vidicon having a diameter of 25 mm. The vidicon storage surface (target) is a selenium-sulfur film having an active area of 11.14 x 11.14 mm; it holds a frame consisting of 800 lines with 800 picture elements per line. Pictures of Jupiter, Saturn, and their moons are presented, with short descriptions given of the area being viewed.

Video Capture of Plastic Surgery Procedures Using the GoPro HERO 3+.

PubMed

Graves, Steven Nicholas; Shenaq, Deana Saleh; Langerman, Alexander J; Song, David H

2015-02-01

Significant improvements can be made in recoding surgical procedures, particularly in capturing high-quality video recordings from the surgeons' point of view. This study examined the utility of the GoPro HERO 3+ Black Edition camera for high-definition, point-of-view recordings of plastic and reconstructive surgery. The GoPro HERO 3+ Black Edition camera was head-mounted on the surgeon and oriented to the surgeon's perspective using the GoPro App. The camera was used to record 4 cases: 2 fat graft procedures and 2 breast reconstructions. During cases 1-3, an assistant remotely controlled the GoPro via the GoPro App. For case 4 the GoPro was linked to a WiFi remote, and controlled by the surgeon. Camera settings for case 1 were as follows: 1080p video resolution; 48 fps; Protune mode on; wide field of view; 16:9 aspect ratio. The lighting contrast due to the overhead lights resulted in limited washout of the video image. Camera settings were adjusted for cases 2-4 to a narrow field of view, which enabled the camera's automatic white balance to better compensate for bright lights focused on the surgical field. Cases 2-4 captured video sufficient for teaching or presentation purposes. The GoPro HERO 3+ Black Edition camera enables high-quality, cost-effective video recording of plastic and reconstructive surgery procedures. When set to a narrow field of view and automatic white balance, the camera is able to sufficiently compensate for the contrasting light environment of the operating room and capture high-resolution, detailed video.

Optical design of space cameras for automated rendezvous and docking systems

NASA Astrophysics Data System (ADS)

Zhu, X.

2018-05-01

Visible cameras are essential components of a space automated rendezvous and docking (AR and D) system, which is utilized in many space missions including crewed or robotic spaceship docking, on-orbit satellite servicing, autonomous landing and hazard avoidance. Cameras are ubiquitous devices in modern time with countless lens designs that focus on high resolution and color rendition. In comparison, space AR and D cameras, while are not required to have extreme high resolution and color rendition, impose some unique requirements on lenses. Fixed lenses with no moving parts and separated lenses for narrow and wide field-of-view (FOV) are normally used in order to meet high reliability requirement. Cemented lens elements are usually avoided due to wide temperature swing and outgassing requirement in space environment. The lenses should be designed with exceptional straylight performance and minimum lens flare given intense sun light and lacking of atmosphere scattering in space. Furthermore radiation resistant glasses should be considered to prevent glass darkening from space radiation. Neptec has designed and built a narrow FOV (NFOV) lens and a wide FOV (WFOV) lens for an AR and D visible camera system. The lenses are designed by using ZEMAX program; the straylight performance and the lens baffles are simulated by using TracePro program. This paper discusses general requirements for space AR and D camera lenses and the specific measures for lenses to meet the space environmental requirements.

An improved camera trap for amphibians, reptiles, small mammals, and large invertebrates

PubMed Central

2017-01-01

Camera traps are valuable sampling tools commonly used to inventory and monitor wildlife communities but are challenged to reliably sample small animals. We introduce a novel active camera trap system enabling the reliable and efficient use of wildlife cameras for sampling small animals, particularly reptiles, amphibians, small mammals and large invertebrates. It surpasses the detection ability of commonly used passive infrared (PIR) cameras for this application and eliminates problems such as high rates of false triggers and high variability in detection rates among cameras and study locations. Our system, which employs a HALT trigger, is capable of coupling to digital PIR cameras and is designed for detecting small animals traversing small tunnels, narrow trails, small clearings and along walls or drift fencing. PMID:28981533

Investigation of newly discovered lobate scarps: Implications for the tectonic and thermal evolution of the Moon

NASA Astrophysics Data System (ADS)

Clark, Jaclyn D.; Hurtado, José M.; Hiesinger, Harald; van der Bogert, Carolyn H.; Bernhardt, Hannes

2017-12-01

Using observations of lunar scarps in Apollo Panoramic Camera photos, Binder and Gunga (1985) tested competing models for the initial thermal state of the Moon, i.e., whether it was initially completely molten or if the molten portion was limited to a global magma ocean. Binder and Gunga (1985) favored the concept of an initially molten Moon that had entered into a late-stage epoch of global tectonism. Since the start of the Lunar Reconnaissance Orbiter mission, thousands of new small lobate scarps have been identified across the lunar surface with high-resolution images from the Lunar Reconnaissance Orbiter Camera (LROC). As such, we selected spatially random scarps and reevaluated the fault dynamical calculations presented by Binder and Gunga (1985). Additionally, we examined the geometry and properties of these fault scarps and place better constraints on the amount of scarp-related crustal shortening. We found that these low angle thrust faults (∼23˚) have an average relief of ∼40 m and average depths of 951 m. Using crater size-frequency distribution (CSFD) measurements, we derived absolute model ages for the scarp surfaces proximal to the trace of the fault and found that the last slip event occurred in the last ∼132 Ma. Along with young model ages, lunar lobate scarps exhibit a youthful appearance with their crisp morphologies which is indicative of late-stage horizontal shortening. In conclusion, interior secular cooling and tidal stresses cause global contraction of the Moon.

Peak-ring structure and kinematics from a multi-disciplinary study of the Schrödinger impact basin

PubMed Central

Kring, David A.; Kramer, Georgiana Y.; Collins, Gareth S.; Potter, Ross W. K.; Chandnani, Mitali

2016-01-01

The Schrödinger basin on the lunar farside is ∼320 km in diameter and the best-preserved peak-ring basin of its size in the Earth–Moon system. Here we present spectral and photogeologic analyses of data from the Moon Mineralogy Mapper instrument on the Chandrayaan-1 spacecraft and the Lunar Reconnaissance Orbiter Camera (LROC) on the LRO spacecraft, which indicates the peak ring is composed of anorthositic, noritic and troctolitic lithologies that were juxtaposed by several cross-cutting faults during peak-ring formation. Hydrocode simulations indicate the lithologies were uplifted from depths up to 30 km, representing the crust of the lunar farside. Through combining geological and remote-sensing observations with numerical modelling, we show that a Displaced Structural Uplift model is best for peak rings, including that in the K–T Chicxulub impact crater on Earth. These results may help guide sample selection in lunar sample return missions that are being studied for the multi-agency International Space Exploration Coordination Group. PMID:27762265

LROC WAC Ultraviolet Reflectance of the Moon

NASA Astrophysics Data System (ADS)

Robinson, M. S.; Denevi, B. W.; Sato, H.; Hapke, B. W.; Hawke, B. R.

2011-10-01

Earth-based color filter photography, first acquired in the 1960s, showed color differences related to morphologic boundaries on the Moon [1]. These color units were interpreted to indicate compositional differences, thought to be the result of variations in titanium content [1]. Later it was shown that iron abundance (FeO) also plays a dominant role in controlling color in lunar soils [2]. Equally important is the maturity of a lunar soil in terms of its reflectance properties (albedo and color) [3]. Maturity is a measure of the state of alteration of surface materials due to sputtering and high velocity micrometeorite impacts over time [3]. The Clementine (CL) spacecraft provided the first global and digital visible through infrared observations of the Moon [4]. This pioneering dataset allowed significant advances in our understanding of compositional (FeO and TiO2) and maturation differences across the Moon [5,6]. Later, the Lunar Prospector (LP) gamma ray and neutron experiments provided the first global, albeit low resolution, elemental maps [7]. Newly acquired Moon Mineralogic Mapper hyperspectral measurements are now providing the means to better characterize mineralogic variations on a global scale [8]. Our knowledge of ultraviolet color differences between geologic units is limited to low resolution (km scale) nearside telescopic observations, and high resolution Hubble Space Telescope images of three small areas [9], and laboratory analyses of lunar materials [10,11]. These previous studies detailed color differences in the UV (100 to 400 nm) related to composition and physical state. HST UV (250 nm) and visible (502 nm) color differences were found to correlate with TiO2, and were relatively insensitive to maturity effects seen in visible ratios (CL) [9]. These two results led to the conclusion that improvements in TiO2 estimation accuracy over existing methods may be possible through a simple UV/visible ratio [9]. The Lunar Reconnaissance Orbiter Camera (LROC) Wide Angle Camera (WAC) provides the first global lunar ultraviolet through visible (321 nm to 689 nm) multispectral observations [12]. The WAC is a sevencolor push-frame imager with nominal resolutions of 400 m (321, 360 nm) and 100 m (415, 566, 604, 643, 689 nm). Due to its wide field-of-view (60° in color mode) the phase angle within a single line varies ±30°, thus requiring the derivation of a precise photometric characterization [13] before any interpretations of lunar reflectance properties can be made. The current WAC photometric correction relies on multiple WAC observations of the same area over a broad range of phase angles and typically results in relative corrections good to a few percent [13].

Saturnian Snowman

NASA Image and Video Library

2015-10-15

NASA's Cassini spacecraft spied this tight trio of craters as it approached Saturn's icy moon Enceladus for a close flyby on Oct. 14, 2015. The craters, located at high northern latitudes, are sliced through by thin fractures -- part of a network of similar cracks that wrap around the snow-white moon. The image was taken in visible light with the Cassini spacecraft narrow-angle camera on Oct. 14, 2015 at a distance of approximately 6,000 miles (10,000 kilometers) from Enceladus. Image scale is 197 feet (60 meters) per pixel. The image was taken with the Cassini spacecraft narrow-angle camera on Oct. 14, 2015 using a spectral filter which preferentially admits wavelengths of ultraviolet light centered at 338 nanometers. http://photojournal.jpl.nasa.gov/catalog/PIA20011

Lunar Reconnaissance Orbiter

NASA Astrophysics Data System (ADS)

Morgan, T.; Chin, G.

2007-08-01

NASA's Lunar Reconnaissance Orbiter (LRO) plans to launch in October 2008 with a companion secondary impactor mission, LCROSS, as the inaugural missions for the Exploration System Mission Directorate. LRO is a pathfinder whose objective is to obtain the needed information to prepare for eventual human return to the Moon. LRO will undertake at least one baseline year of operation with additional extended mission phase sponsored by NASA's Science Mission Directorate. LRO will employ six individual instruments to produce accurate maps and high-resolution images of future landing sites, to assess potential lunar resources, and to characterize the radiation environment. LRO will also test the feasibility of one advanced technology demonstration package. The LRO payload includes: Lunar Orbiter Laser Altimeter (LOLA) which will determine the global topography of the lunar surface at high resolution, measure landing site slopes, surface roughness, and search for possible polar surface ice in shadowed regions; Lunar Reconnaissance Orbiter Camera (LROC) which will acquire targeted narrow angle images of the lunar surface capable of resolving meter-scale features to support landing site selection, as well as wide-angle images to characterize polar illumination conditions and to identify potential resources; Lunar Exploration Neutron Detector (LEND) which will map the flux of neutrons from the lunar surface to search for evidence of water ice, and will provide space radiation environment measurements that may be useful for future human exploration; Diviner Lunar Radiometer Experiment (DLRE) which will chart the temperature of the entire lunar surface at approximately 300 meter horizontal resolution to identify cold-traps and potential ice deposits; Lyman-Alpha Mapping Project (LAMP) which will map the entire lunar surface in the far ultraviolet. LAMP will search for surface ice and frost in the polar regions and provide images of permanently shadowed regions illuminated only by starlight; Cosmic Ray Telescope for the Effects of Radiation (CRaTER), which will investigate the effect of galactic cosmic rays on tissue-equivalent plastics as a constraint on models of biological response to background space radiation. The technology demonstration is an advanced radar (mini-RF) that will demonstrate X- and S-band radar imaging and interferometry using a light-weight synthetic aperture radar.

Future Exploration of the South Pole as Enabled by the Lunar Reconnaissance Orbiter

NASA Astrophysics Data System (ADS)

Speyerer, E. J.; Lawrence, S. J.; Stopar, J.

2016-12-01

The Lunar Reconnaissance Orbiter (LRO) launched in 2009 to collect the dataset required for future surface missions and to answer key questions about the lunar surface environment. In the first seven years of operations, the Lunar Reconnaissance Orbiter Camera (LROC) acquired over a million images of the lunar surface and collected key stereo observations for the production of meter-scale digital terrain models. Due to the configuration of the LRO orbit, LROC and the other onboard instruments have the opportunity to acquire observations at or near the poles every two hours. The lunar south polar region is an area of interest for future surface missions due to the benign thermal environment and areas of near-continuous illumination. These persistently illuminated regions are also adjacent to permanently shadowed areas (e.g. floors of craters and local depressions) that are of interest to both scientists and engineers prospecting for cold-trapped volatiles on or near the surface for future in situ resource utilization. Using a terramechanics model based on surface properties derived during the Apollo and Luna missions, we evaluated the accessibility of different science targets and the optimal traverse paths for a given set of waypoints. Assuming a rover that relies primarily on solar power, we identified a traverse that would keep the rover illuminated for 94.43% of the year between 1 January 2021 and 31 December 2021. Throughout this year-long period, the longest eclipse endured by the rover would last only 101 hours and the rover would move a total of 22.11 km with an average speed of 2.5 m/hr (max speed=30 m/hr). During this time the rover would be able to explore a variety of targets along the connecting ridge between Shackleton and de Gerlache craters. In addition to the southern polar regions, we are also examining traverses around other key exploration sites such as Marius Hills, Ina-D, Rima Parry, and the Mairan Domes in efforts to aid future mission planners and assess the requirements for future roving prospectors (e.g., maximum speed, maximum slope, etc.).

Mini-RF and LROC observations of mare crater layering relationships

NASA Astrophysics Data System (ADS)

Stickle, A. M.; Patterson, G. W.; Cahill, J. T. S.; Bussey, D. B. J.

2016-07-01

The lunar maria cover approximately 17% of the Moon's surface. Discerning discrete subsurface layers in the mare provides some constraints on thickness and volume estimates of mare volcanism. Multiple types of data and measurement techniques allow probing the subsurface and provide insights into these layers, including detailed examination of impact craters, mare pits and sinuous rilles, and radar sounders. Unfortunately, radar sounding includes many uncertainties about the material properties of the lunar surface that may influence estimates of layer depth and thickness. Because they distribute material from depth onto the surface, detailed examination of impact ejecta blankets provides a reliable way to examine deeper material using orbital instruments such as cameras, spectrometers, or imaging radars. Here, we utilize Miniature Radio Frequency (Mini-RF) data to investigate the scattering characteristics of ejecta blankets of young lunar craters. We use Circular Polarization Ratio (CPR) information from twenty-two young, fresh lunar craters to examine how the scattering behavior changes as a function of radius from the crater rim. Observations across a range of crater size and relative ages exhibit significant diversity within mare regions. Five of the examined craters exhibit profiles with no shelf of constant CPR near the crater rim. Comparing these CPR profiles with LROC imagery shows that the magnitude of the CPR may be an indication of crater degradation state; this may manifest differently at radar compared to optical wavelengths. Comparisons of radar and optical data also suggest relationships between subsurface stratigraphy and structure in the mare and the block size of the material found within the ejecta blanket. Of the examined craters, twelve have shelves of approximately constant CPR as well as discrete layers outcropping in the subsurface, and nine fall along a trend line when comparing shelf-width with thickness of subsurface layers. These observations suggest that surface CPR measurements may be used to identify near-surface layering. Here, we use ejected material to probe the subsurface, allowing observations of near-surface stratigraphy that may be otherwise hidden by layers higher from remote observations.

Future Exploration of the South Pole as Enabled by the Lunar Reconnaissance Orbiter

NASA Technical Reports Server (NTRS)

Speyerer, Emerson J.; Lawrence, Samuel J.; Stopar, Julie

2016-01-01

The Lunar Reconnaissance Orbiter (LRO) launched in 2009 to collect the dataset required for future surface missions and to answer key questions about the lunar surface environment. In the first seven years of operations, the Lunar Reconnaissance Orbiter Camera (LROC) acquired over a million images of the lunar surface and collected key stereo observations for the production of meter-scale digital terrain models. Due to the configuration of the LRO orbit, LROC and the other onboard instruments have the opportunity to acquire observations at or near the poles every two hours. The lunar south polar region is an area of interest for future surface missions due to the benign thermal environment and areas of near-continuous illumination. These persistently illuminated regions are also adjacent to permanently shadowed areas (e.g. floors of craters and local depressions) that are of interest to both scientists and engineers prospecting for cold-trapped volatiles on or near the surface for future in situ resource utilization. Using a terramechanics model based on surface properties derived during the Apollo and Luna missions, we evaluated the accessibility of different science targets and the optimal traverse paths for a given set of waypoints. Assuming a rover that relies primarily on solar power, we identified a traverse that would keep the rover illuminated for 94.43% of the year between 1 January 2021 and 31 December 2021. Throughout this year-long period, the longest eclipse endured by the rover would last only 101 hours and the rover would move a total of 22.11 km with an average speed of 2.5 m/hr (max speed=30 m/hr). During this time the rover would be able to explore a variety of targets along the connecting ridge between Shackleton and de Gerlache craters. In addition to the southern polar regions, we are also examining traverses around other key exploration sites such as Marius Hills, Ina-D, Rima Parry, and the Mairan Domes in efforts to aid future mission planners and assess the requirements for future roving prospectors (e.g., maximum speed, maximum slope, etc.).

Lunar Floor-Fractured Craters: Classification, Distribution and Implications for Magmatism and Shallow Crustal Structure

NASA Technical Reports Server (NTRS)

Jozwiak, L. M.; Head, J. W.; Neumann, G. A.; Zuber, M. T.; Smith, D. E.

2012-01-01

Floor-fractured craters (FFCs) are a class of lunar craters defined by their distinctly shallow, often plate-like floors, and combinations of radial, con-centric, and polygonal floor-fractures; a variety of other interior features are often observed, such as moats, ridges, small dark-haloed pits, and patches of mare material. They were first classified by Schultz [1] , who recognized eight overall types of floor-fractured crater. These eight subtypes have widely differing appearances, a factor that could provide insight into formation mechanisms (different manifestations of the same mechanism, or indicators of varying formation mechanisms). Two formation mechanisms for FFCs were initially proposed: 1) magmatic intrusion [1], in which magma rising toward the surface in dikes encountered low-density breccia lenses beneath crater floors and spread laterally to form sills, raising and fracturing the crater floor. 2) viscous relaxation [2], in which the properties of the crust permitted viscous flow in the vicinity of the crater, causing long-wavelength relaxation of the topography and uplift and fracturing of the crater floor. Critical to distinguishing between these two end-member hypotheses and identifying others is a quantitative assessment of the topography of FFCs and knowledge of their regional and local settings. The purpose of this study is to use newly available Lunar Reconnaissance Orbiter (LRO) Lunar Orbiter Laser Altimeter (LOLA) altimeter and Lunar Reconnaissance Orbiter Camera (LROC) image data to provide an updated global catalog of the locations, classes, morphometric and morphologic characteristics of all lunar floor-fractured craters. We use the excellent 8-class system initially described in Schultz [1] as a starting point for classification and the enhanced LOLA/LROC data sets to examine and categorize all FFCs; we found evidence for a new FFC class, discernably different from the previously existing types. Our approach, and the global categorization of all FFCs, permits the spatial distribution of each FFC-subtype to be plotted and assessed allowing for further investigation into FFC formation mechanisms. Upon completion, the data set will be made available on our web site at http://www.planetary.brown.edu/html_pages/data.htm.

Application of narrow-band television to industrial and commercial communications

NASA Technical Reports Server (NTRS)

Embrey, B. C., Jr.; Southworth, G. R.

1974-01-01

The development of narrow-band systems for use in space systems is presented. Applications of the technology to future spacecraft requirements are discussed along with narrow-band television's influence in stimulating development within the industry. The transferral of the technology into industrial and commercial communications is described. Major areas included are: (1) medicine; (2) education; (3) remote sensing for traffic control; and (5) weather observation. Applications in data processing, image enhancement, and information retrieval are provided by the combination of the TV camera and the computer.

GLD100 - Lunar topography from LROC WAC stereo

NASA Astrophysics Data System (ADS)

Scholten, F.; Oberst, J.; Robinson, M. S.

2011-10-01

The LROC WAC instrument of the LRO mission comprises substantial stereo image data from adjacent orbits. Multiple coverage of the entire surface of the Moon at a mean ground scale of 75 m/pxl has already been achieved within the first two years of the mission. We applied photogrammetric stereo processing methods for the derivation of a 100 m raster DTM (digital terrain model), called GLD100, from several tens of thousands stereo models. The GLD100 covers the lunar surface between 80° northern and southern latitude. Polar regions are excluded because of poor illumination and stereo conditions. Vertical differences of the GLD100 to altimetry data from the LRO LOLA instrument are small, the mean deviation is typically about 20 m, without systematic lateral or vertical offsets.

Video Capture of Plastic Surgery Procedures Using the GoPro HERO 3+

PubMed Central

Graves, Steven Nicholas; Shenaq, Deana Saleh; Langerman, Alexander J.

2015-01-01

Background: Significant improvements can be made in recoding surgical procedures, particularly in capturing high-quality video recordings from the surgeons’ point of view. This study examined the utility of the GoPro HERO 3+ Black Edition camera for high-definition, point-of-view recordings of plastic and reconstructive surgery. Methods: The GoPro HERO 3+ Black Edition camera was head-mounted on the surgeon and oriented to the surgeon’s perspective using the GoPro App. The camera was used to record 4 cases: 2 fat graft procedures and 2 breast reconstructions. During cases 1-3, an assistant remotely controlled the GoPro via the GoPro App. For case 4 the GoPro was linked to a WiFi remote, and controlled by the surgeon. Results: Camera settings for case 1 were as follows: 1080p video resolution; 48 fps; Protune mode on; wide field of view; 16:9 aspect ratio. The lighting contrast due to the overhead lights resulted in limited washout of the video image. Camera settings were adjusted for cases 2-4 to a narrow field of view, which enabled the camera’s automatic white balance to better compensate for bright lights focused on the surgical field. Cases 2-4 captured video sufficient for teaching or presentation purposes. Conclusions: The GoPro HERO 3+ Black Edition camera enables high-quality, cost-effective video recording of plastic and reconstructive surgery procedures. When set to a narrow field of view and automatic white balance, the camera is able to sufficiently compensate for the contrasting light environment of the operating room and capture high-resolution, detailed video. PMID:25750851

Miranda

NASA Image and Video Library

1999-08-24

One wide-angle and eight narrow-angle camera images of Miranda, taken by NASA Voyager 2, were combined in this view. The controlled mosaic was transformed to an orthographic view centered on the south pole.

Geoanalyses of Lunokhods' regions for future Lunar missions and data access via Geoportal

NASA Astrophysics Data System (ADS)

Karachevtseva, Irina; Baskakova, Marina; Gusakova, Eugenia; Kokhanov, Alexander; Kozlova, Natalia; Matveev, Eugeny; Nadezhdina, Irina; Zubarev, Anatoliy; Oberst, Juergen

2013-04-01

Introduction: The Soviet rover missions Lunokhod-1 and -2 were launched at the beginning of 70th (Luna-17 in October 1971 and Luna-21 in January 1973 respectively). The main goals of the both missions were to study Moon surface in situ. The history of the Lunokhods' missions came back into focus recently, when the Lunar Reconnaissance Orbiter obtained high resolutions images. Sources. For our work we used various data: LROC Narrow Angle Camera (LRO NAC) images, 0.3-1 m/pixel [7, 11]; DEMs with different resolution: LRO NAC DEM, 1-5 m/pixel [9]; Kaguya DEM, 7.5 m/pixel [10]; Lunokhods' stereo panoramas and early cartography information [1, 8]. Methodolody: We collected all data as spatial database (Geodatabase) which includes various derived products. Based on methods developed earlier [4, 6], rovers wheel tracks and craters entire study regions were mapped. High resolution DEMs allow calculate of various morphometric parameters of the Lunokhods' regions which provide better understanding processes on lunar surface [2, 5]. Method of detailed morphology analyses developed for study area now used for investigation of the Luna-Glob and Luna-Resource landing missions which are planned to the south pole of the Moon. Data access: We are developing easy access to the planetary data based on web and spatial technology (Geoportal). Geoportal provides the ability to view spatial data in the web-browser, displays different layers in the same area at different scales turns the web. Lunokhods' data point features were created for each station of rover routes where panoramas were been recorded. So GIS project provide an easy access to non-spatial image database and can involve these information in their spatial context. Conclusions: During Lunokhods' missions early topography data of the traverses were accurate for most areas. Modern estimating these results based on the new LRO data provide comparative studies in lunar geology and morphology. We show that these data can be used for detailed mapping of landing sites for future lunar exploration missions (Luna-Globe and Luna-Recourse). Using PDS4 standard [3] we are developing Geoportal for easy access to the Lunokhods' panoramas and derived products based on results of newest lunar missions. Acknowledgements: We would like to express our acknowledgements to Alexander Basilevsky for valuable advice and support. This work has been partly supported by Seventh Framework Programme (project PRoViDE - Planetary Robotics Vision Data Exploitation, Agreement no. 3123770). References: [1] Barsukov et al. (1978) Peredvijnaya laboratoriya na Lune Lunokhod-1, Vol. 2. Nauka (in Russian). [2] Basilevsky A. et al. (2012). LPS XLIII, Abstract #1481. [3] Crichton D. (2012), Planetary Data Work-shop, USA, Flagstaff. [4] Gusakova E. et al. (2012) LPS XLIII, Abstract #1750. [5] Gusakova E. et al. (2013) LPS XLIV, Abstract #1174. [6] Karachevtseva I. et al. (2012) PSS (submitted in November). [7] Robinson M. S et al., (2010). Space Science Reviews, Volume 150, Issue 1-4, pp. 81-124. [8] Vinogradov et al. (1971) Peredvijnaya laboratoriya na Lune Lunokhod-1, Vol. 1. Nauka (in Russian). [9] Zubarev A. E. et al. (2012) 3M - S3. P173-174. [10] http://l2db.selene.darts.isas.jaxa.jp/cgi-bin/search.cgi [11] http://www.lroc.asu.edu/

Acapulco, Mexico taken with electronic still camera

NASA Image and Video Library

1995-10-29

STS073-E-5275 (3 Nov. 1995) --- Resort City of Acapulco appears in this north-looking view, photographed from the Earth-orbiting space shuttle Columbia with the Electronic Still Camera (ESC). The airport lies on a narrow neck of land between the sea and a large coastal lagoon. This mission marks the first time NASA has released in mid-flight electronically-downlinked color images that feature geographic subject matter.

Improved iris localization by using wide and narrow field of view cameras for iris recognition

NASA Astrophysics Data System (ADS)

Kim, Yeong Gon; Shin, Kwang Yong; Park, Kang Ryoung

2013-10-01

Biometrics is a method of identifying individuals by their physiological or behavioral characteristics. Among other biometric identifiers, iris recognition has been widely used for various applications that require a high level of security. When a conventional iris recognition camera is used, the size and position of the iris region in a captured image vary according to the X, Y positions of a user's eye and the Z distance between a user and the camera. Therefore, the searching area of the iris detection algorithm is increased, which can inevitably decrease both the detection speed and accuracy. To solve these problems, we propose a new method of iris localization that uses wide field of view (WFOV) and narrow field of view (NFOV) cameras. Our study is new as compared to previous studies in the following four ways. First, the device used in our research acquires three images, one each of the face and both irises, using one WFOV and two NFOV cameras simultaneously. The relation between the WFOV and NFOV cameras is determined by simple geometric transformation without complex calibration. Second, the Z distance (between a user's eye and the iris camera) is estimated based on the iris size in the WFOV image and anthropometric data of the size of the human iris. Third, the accuracy of the geometric transformation between the WFOV and NFOV cameras is enhanced by using multiple matrices of the transformation according to the Z distance. Fourth, the searching region for iris localization in the NFOV image is significantly reduced based on the detected iris region in the WFOV image and the matrix of geometric transformation corresponding to the estimated Z distance. Experimental results showed that the performance of the proposed iris localization method is better than that of conventional methods in terms of accuracy and processing time.

The Sculptured Hills of the Taurus Highlands: Implications for the relative age of Serenitatis, basin chronologies and the cratering history of the Moon

USGS Publications Warehouse

Spudis, P.D.; Wilhelms, D.E.; Robinson, M.S.

2011-01-01

New images from the Lunar Reconnaissance Orbiter Camera show the distribution and geological relations of the Sculptured Hills, a geological unit widespread in the highlands between the Serenitatis and Crisium basins. The Sculptured Hills shows knobby, undulating, radially textured, and plains-like morphologies and in many places is indistinguishable from the similarly knobby Alpes Formation, a facies of ejecta from the Imbrium basin. The new LROC image data show that the Sculptured Hills in the Taurus highlands is Imbrium ejecta and not directly related to the formation of the Serenitatis basin. This occurrence and the geological relations of this unit suggests that the Apollo 17 impact melts may not be not samples of the Serenitatis basin-forming impact, leaving their provenance undetermined and origin unexplained. If the Apollo 17 melt rocks are Serenitatis impact melt, up to half of the basin and large crater population of the Moon was created within a 30 Ma interval around 3.8 Ga in a global impact "cataclysm." Either interpretation significantly changes our view of the impact process and history of the Earth-Moon system. Copyright 2011 by the American Geophysical Union.

MESSENGER Departs Mercury

NASA Image and Video Library

2008-01-30

After NASA MESSENGER spacecraft completed its successful flyby of Mercury, the Narrow Angle Camera NAC, part of the Mercury Dual Imaging System MDIS, took these images of the receding planet. This is a frame from an animation.

Telescope and mirrors development for the monolithic silicon carbide instrument of the osiris narrow angle camera

NASA Astrophysics Data System (ADS)

Calvel, Bertrand; Castel, Didier; Standarovski, Eric; Rousset, Gérard; Bougoin, Michel

2017-11-01

The international Rosetta mission, now planned by ESA to be launched in January 2003, will provide a unique opportunity to directly study the nucleus of comet 46P/Wirtanen and its activity in 2013. We describe here the design, the development and the performances of the telescope of the Narrow Angle Camera of the OSIRIS experiment et its Silicon Carbide telescope which will give high resolution images of the cometary nucleus in the visible spectrum. The development of the mirrors has been specifically detailed. The SiC parts have been manufactured by BOOSTEC, polished by STIGMA OPTIQUE and ion figured by IOM under the prime contractorship of ASTRIUM. ASTRIUM was also in charge of the alignment. The final optical quality of the aligned telescope is 30 nm rms wavefront error.

Neptune Great Dark Spot in High Resolution

NASA Image and Video Library

1999-08-30

This photograph shows the last face on view of the Great Dark Spot that Voyager will make with the narrow angle camera. The image was shuttered 45 hours before closest approach at a distance of 2.8 million kilometers (1.7 million miles). The smallest structures that can be seen are of an order of 50 kilometers (31 miles). The image shows feathery white clouds that overlie the boundary of the dark and light blue regions. The pinwheel (spiral) structure of both the dark boundary and the white cirrus suggest a storm system rotating counterclockwise. Periodic small scale patterns in the white cloud, possibly waves, are short lived and do not persist from one Neptunian rotation to the next. This color composite was made from the clear and green filters of the narrow-angle camera. http://photojournal.jpl.nasa.gov/catalog/PIA00052

MESSENGER Reveals Mercury in New Detail

NASA Image and Video Library

2008-01-16

As NASA MESSENGER approached Mercury on January 14, 2008, the spacecraft Narrow-Angle Camera on the Mercury Dual Imaging System MDIS instrument captured this view of the planet rugged, cratered landscape illuminated obliquely by the Sun.

Still from Red Spot Movie

NASA Image and Video Library

2000-11-21

This image is one of seven from the narrow-angle camera on NASA Cassini spacecraft assembled as a brief movie of cloud movements on Jupiter. The smallest features visible are about 500 kilometers about 300 miles across.

Standards-Based Open-Source Planetary Map Server: Lunaserv

NASA Astrophysics Data System (ADS)

Estes, N. M.; Silva, V. H.; Bowley, K. S.; Lanjewar, K. K.; Robinson, M. S.

2018-04-01

Lunaserv is a planetary capable Web Map Service developed by the LROC SOC. It enables researchers to serve their own planetary data to a wide variety of GIS clients without any additional processing or download steps.

Exploring Space Weathering on Mercury Using Global UV-VIS Reflectance Spectroscopy

NASA Astrophysics Data System (ADS)

Izenberg, N. R.; Denevi, B. W.

2018-05-01

We apply UV analysis methods used on lunar LROC data to Mercury to explore space weathering maturity and possibly evidence of shocked minerals. What says the UV // about shock, maturity // on dear Mercury?

Defining Long-Duration Traverses of Lunar Volcanic Complexes with LROC NAC Images

NASA Technical Reports Server (NTRS)

Stopar, J. D.; Lawrence, S. J.; Joliff, B. L.; Speyerer, E. J.; Robinson, M. S.

2016-01-01

A long-duration lunar rover [e.g., 1] would be ideal for investigating large volcanic complexes like the Marius Hills (MH) (approximately 300 x 330 km), where widely spaced sampling points are needed to explore the full geologic and compositional variability of the region. Over these distances, a rover would encounter varied surface morphologies (ranging from impact craters to rugged lava shields), each of which need to be considered during the rover design phase. Previous rovers including Apollo, Lunokhod, and most recently Yutu, successfully employed pre-mission orbital data for planning (at scales significantly coarser than that of the surface assets). LROC was specifically designed to provide mission-planning observations at scales useful for accurate rover traverse planning (crewed and robotic) [2]. After-the-fact analyses of the planning data can help improve predictions of future rover performance [e.g., 3-5].

The PAUCam readout electronics system

NASA Astrophysics Data System (ADS)

Jiménez, Jorge; Illa, José M.; Cardiel-Sas, Laia; de Vicente, Juan; Castilla, Javier; Casas, Ricard

2016-08-01

The PAUCam is an optical camera with a wide field of view of 1 deg x 1 deg and up to 46 narrow and broad band filters. The camera is already installed on the William Herschel Telescope (WHT) in the Canary Islands, Spain and successfully commissioned during the first period of 2015. The paper presents the main results from the readout electronics commissioning tests and include an overview of the whole readout electronics system, its configuration and current performance.

Serious Gaming Technologies Support Human Factors Investigations of Advanced Interfaces for Semi-Autonomous Vehicles

DTIC Science & Technology

2006-06-01

conventional camera vs. thermal imager vs. night vision; camera field of view (narrow, wide, panoramic); keyboard + mouse vs. joystick control vs...motorised platform which could scan the immediate area, producing a 360o panorama of “stitched-together” digital pictures. The picture file, together with...VBS was used to automate the process of creating a QuickTime panorama (.mov or .qt), which includes the initial retrieval of the images, the

MEANS FOR VISUALIZING FLUID FLOW PATTERNS

DOEpatents

Lynch, F.E.; Palmer, L.D.; Poppendick, H.F.; Winn, G.M.

1961-05-16

An apparatus is given for determining both the absolute and relative velocities of a phosphorescent fluid flowing through a transparent conduit. The apparatus includes a source for exciting a narrow trsnsverse band of the fluid to phosphorescence, detecting means such as a camera located downstream from the exciting source to record the shape of the phosphorescent band as it passes, and a timer to measure the time elapsed between operation of the exciting source and operation of the camera.

Reconditioning of Cassini Narrow-Angle Camera

NASA Technical Reports Server (NTRS)

2002-01-01

These five images of single stars, taken at different times with the narrow-angle camera on NASA's Cassini spacecraft, show the effects of haze collecting on the camera's optics, then successful removal of the haze by warming treatments.

The image on the left was taken on May 25, 2001, before the haze problem occurred. It shows a star named HD339457.

The second image from left, taken May 30, 2001, shows the effect of haze that collected on the optics when the camera cooled back down after a routine-maintenance heating to 30 degrees Celsius (86 degrees Fahrenheit). The star is Maia, one of the Pleiades.

The third image was taken on October 26, 2001, after a weeklong decontamination treatment at minus 7 C (19 F). The star is Spica.

The fourth image was taken of Spica January 30, 2002, after a weeklong decontamination treatment at 4 C (39 F).

The final image, also of Spica, was taken July 9, 2002, following three additional decontamination treatments at 4 C (39 F) for two months, one month, then another month.

Cassini, on its way toward arrival at Saturn in 2004, is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Cassini mission for NASA's Office of Space Science, Washington, D.C.

The Wide Angle Camera of the ROSETTA Mission

NASA Astrophysics Data System (ADS)

Barbieri, C.; Fornasier, S.; Verani, S.; Bertini, I.; Lazzarin, M.; Rampazzi, F.; Cremonese, G.; Ragazzoni, R.; Marzari, F.; Angrilli, F.; Bianchini, G. A.; Debei, S.; Dececco, M.; Guizzo, G.; Parzianello, G.; Ramous, P.; Saggin, B.; Zaccariotto, M.; Da Deppo, V.; Naletto, G.; Nicolosi, G.; Pelizzo, M. G.; Tondello, G.; Brunello, P.; Peron, F.

This paper aims to give a brief description of the Wide Angle Camera (WAC), built by the Centro Servizi e AttivitàSpaziali (CISAS) of the University of Padova for the ESA ROSETTA Mission to comet 46P/Wirtanen and asteroids 4979 Otawara and 140 Siwa. The WAC is part of the OSIRIS imaging system, which comprises also a Narrow Angle Camera (NAC) built by the Laboratoire d'Astrophysique Spatiale (LAS) of Marseille. CISAS had also the responsibility to build the shutter and the front cover mechanism for the NAC. The flight model of the WAC was delivered in December 2001, and has been already integrated on ROSETTA.

Flame Imaging System

NASA Technical Reports Server (NTRS)

Barnes, Heidi L. (Inventor); Smith, Harvey S. (Inventor)

1998-01-01

A system for imaging a flame and the background scene is discussed. The flame imaging system consists of two charge-coupled-device (CCD) cameras. One camera uses a 800 nm long pass filter which during overcast conditions blocks sufficient background light so the hydrogen flame is brighter than the background light, and the second CCD camera uses a 1100 nm long pass filter, which blocks the solar background in full sunshine conditions such that the hydrogen flame is brighter than the solar background. Two electronic viewfinders convert the signal from the cameras into a visible image. The operator can select the appropriate filtered camera to use depending on the current light conditions. In addition, a narrow band pass filtered InGaAs sensor at 1360 nm triggers an audible alarm and a flashing LED if the sensor detects a flame, providing additional flame detection so the operator does not overlook a small flame.

Ridges and Cliffs on Mercury Surface

NASA Image and Video Library

2008-01-20

A complex history of geological evolution is recorded in this frame from the Narrow Angle Camera NAC, part of the Mercury Dual Imaging System MDIS instrument, taken during NASA MESSENGER close flyby of Mercury on January 14, 2008.

Reflecting on Icy Rhea

NASA Image and Video Library

2009-11-03

Bright sunlight on Rhea shows off the cratered surface of Saturn second largest moon in this image captured by NASA Cassini Orbiter. The image was taken in visible light with the Cassini spacecraft narrow-angle camera on Sept. 21, 2009.

PitScan: Computer-Assisted Feature Detection

NASA Astrophysics Data System (ADS)

Wagner, R. V.; Robinson, M. S.

2018-04-01

We developed PitScan to assist in searching the very large LROC image dataset for pits — unusual <200m wide vertical-walled holes in the Moon's surface. PitScan reduces analysts' workload by pre-filtering images to identify possible pits.

Quantitative Evaluation of a Planetary Renderer for Terrain Relative Navigation

NASA Astrophysics Data System (ADS)

Amoroso, E.; Jones, H.; Otten, N.; Wettergreen, D.; Whittaker, W.

2016-11-01

A ray-tracing computer renderer tool is presented based on LOLA and LROC elevation models and is quantitatively compared to LRO WAC and NAC images for photometric accuracy. We investigated using rendered images for terrain relative navigation.

Plenoptic background oriented schlieren imaging

NASA Astrophysics Data System (ADS)

Klemkowsky, Jenna N.; Fahringer, Timothy W.; Clifford, Christopher J.; Bathel, Brett F.; Thurow, Brian S.

2017-09-01

The combination of the background oriented schlieren (BOS) technique with the unique imaging capabilities of a plenoptic camera, termed plenoptic BOS, is introduced as a new addition to the family of schlieren techniques. Compared to conventional single camera BOS, plenoptic BOS is capable of sampling multiple lines-of-sight simultaneously. Displacements from each line-of-sight are collectively used to build a four-dimensional displacement field, which is a vector function structured similarly to the original light field captured in a raw plenoptic image. The displacement field is used to render focused BOS images, which qualitatively are narrow depth of field slices of the density gradient field. Unlike focused schlieren methods that require manually changing the focal plane during data collection, plenoptic BOS synthetically changes the focal plane position during post-processing, such that all focal planes are captured in a single snapshot. Through two different experiments, this work demonstrates that plenoptic BOS is capable of isolating narrow depth of field features, qualitatively inferring depth, and quantitatively estimating the location of disturbances in 3D space. Such results motivate future work to transition this single-camera technique towards quantitative reconstructions of 3D density fields.

Ladder beam and camera video recording system for evaluating forelimb and hindlimb deficits after sensorimotor cortex injury in rats.

PubMed

Soblosky, J S; Colgin, L L; Chorney-Lane, D; Davidson, J F; Carey, M E

1997-12-30

Hindlimb and forelimb deficits in rats caused by sensorimotor cortex lesions are frequently tested by using the narrow flat beam (hindlimb), the narrow pegged beam (hindlimb and forelimb) or the grid-walking (forelimb) tests. Although these are excellent tests, the narrow flat beam generates non-parametric data so that using more powerful parametric statistical analyses are prohibited. All these tests can be difficult to score if the rat is moving rapidly. Foot misplacements, especially on the grid-walking test, are indicative of an ongoing deficit, but have not been reliably and accurately described and quantified previously. In this paper we present an easy to construct and use horizontal ladder-beam with a camera system on rails which can be used to evaluate both hindlimb and forelimb deficits in a single test. By slow motion videotape playback we were able to quantify and demonstrate foot misplacements which go beyond the recovery period usually seen using more conventional measures (i.e. footslips and footfaults). This convenient system provides a rapid and reliable method for recording and evaluating rat performance on any type of beam and may be useful for measuring sensorimotor recovery following brain injury.

Developing a Low-Cost System for 3d Data Acquisition

NASA Astrophysics Data System (ADS)

Kossieris, S.; Kourounioti, O.; Agrafiotis, P.; Georgopoulos, A.

2017-11-01

In this paper, a developed low-cost system is described, which aims to facilitate 3D documentation fast and reliably by acquiring the necessary data in outdoor environment for the 3D documentation of façades especially in the case of very narrow streets. In particular, it provides a viable solution for buildings up to 8-10m high and streets as narrow as 2m or even less. In cases like that, it is practically impossible or highly time-consuming to acquire images in a conventional way. This practice would lead to a huge number of images and long processing times. The developed system was tested in the narrow streets of a medieval village on the Greek island of Chios. There, in order to by-pass the problem of short taking distances, it was thought to use high definition action cameras together with a 360˚ camera, which are usually provided with very wide-angle lenses and are capable of acquiring images, of high definition, are rather cheap and, most importantly, extremely light. Results suggest that the system can perform fast 3D data acquisition adequate for deliverables of high quality.

Imaging Detonations of Explosives

DTIC Science & Technology

2016-04-01

made using a full-color single-camera pyrometer where wavelength resolution is achieved using the Bayer-type mask covering the sensor chip17 and a...many CHNO- based explosives (e.g., TNT [C7H5N3O6], the formulation C-4 [92% RDX, C3H6N6O6]), hot detonation products are mainly soot and permanent...unreferenced). Essentially, 2 light sensors (cameras), each filtered over a narrow wavelength region, observe an event over the same line of sight. The

Neptune

NASA Image and Video Library

1999-07-25

This image of Neptune was taken through the clear filter of the narrow-angle camera on July 16, 1989 by NASA Voyager 2 spacecraft. The image was processed by computer to show the newly resolved dark oval feature embedded in the middle of the dusky south

Solar System Portrait - View of the Sun, Earth and Venus

NASA Image and Video Library

1996-09-13

This color image of the sun, Earth and Venus was taken by the Voyager 1 spacecraft Feb. 14, 1990, when it was approximately 32 degrees above the plane of the ecliptic and at a slant-range distance of approximately 4 billion miles. It is the first -- and may be the only -- time that we will ever see our solar system from such a vantage point. The image is a portion of a wide-angle image containing the sun and the region of space where the Earth and Venus were at the time with two narrow-angle pictures centered on each planet. The wide-angle was taken with the camera's darkest filter (a methane absorption band), and the shortest possible exposure (5 thousandths of a second) to avoid saturating the camera's vidicon tube with scattered sunlight. The sun is not large in the sky as seen from Voyager's perspective at the edge of the solar system but is still eight million times brighter than the brightest star in Earth's sky, Sirius. The image of the sun you see is far larger than the actual dimension of the solar disk. The result of the brightness is a bright burned out image with multiple reflections from the optics in the camera. The "rays" around the sun are a diffraction pattern of the calibration lamp which is mounted in front of the wide angle lens. The two narrow-angle frames containing the images of the Earth and Venus have been digitally mosaiced into the wide-angle image at the appropriate scale. These images were taken through three color filters and recombined to produce a color image. The violet, green and blue filters were used; exposure times were, for the Earth image, 0.72, 0.48 and 0.72 seconds, and for the Venus frame, 0.36, 0.24 and 0.36, respectively. Although the planetary pictures were taken with the narrow-angle camera (1500 mm focal length) and were not pointed directly at the sun, they show the effects of the glare from the nearby sun, in the form of long linear streaks resulting from the scattering of sunlight off parts of the camera and its sun shade. From Voyager's great distance both Earth and Venus are mere points of light, less than the size of a picture element even in the narrow-angle camera. Earth was a crescent only 0.12 pixel in size. Coincidentally, Earth lies right in the center of one of the scattered light rays resulting from taking the image so close to the sun. Detailed analysis also suggests that Voyager detected the moon as well, but it is too faint to be seen without special processing. Venus was only 0.11 pixel in diameter. The faint colored structure in both planetary frames results from sunlight scattered in the optics. http://photojournal.jpl.nasa.gov/catalog/PIA00450

Solar System Portrait - View of the Sun, Earth and Venus

NASA Technical Reports Server (NTRS)

1990-01-01

This color image of the sun, Earth and Venus was taken by the Voyager 1 spacecraft Feb. 14, 1990, when it was approximately 32 degrees above the plane of the ecliptic and at a slant-range distance of approximately 4 billion miles. It is the first -- and may be the only -- time that we will ever see our solar system from such a vantage point. The image is a portion of a wide-angle image containing the sun and the region of space where the Earth and Venus were at the time with two narrow-angle pictures centered on each planet. The wide-angle was taken with the camera's darkest filter (a methane absorption band), and the shortest possible exposure (5 thousandths of a second) to avoid saturating the camera's vidicon tube with scattered sunlight. The sun is not large in the sky as seen from Voyager's perspective at the edge of the solar system but is still eight million times brighter than the brightest star in Earth's sky, Sirius. The image of the sun you see is far larger than the actual dimension of the solar disk. The result of the brightness is a bright burned out image with multiple reflections from the optics in the camera. The 'rays' around the sun are a diffraction pattern of the calibration lamp which is mounted in front of the wide angle lens. The two narrow-angle frames containing the images of the Earth and Venus have been digitally mosaiced into the wide-angle image at the appropriate scale. These images were taken through three color filters and recombined to produce a color image. The violet, green and blue filters were used; exposure times were, for the Earth image, 0.72, 0.48 and 0.72 seconds, and for the Venus frame, 0.36, 0.24 and 0.36, respectively. Although the planetary pictures were taken with the narrow-angle camera (1500 mm focal length) and were not pointed directly at the sun, they show the effects of the glare from the nearby sun, in the form of long linear streaks resulting from the scattering of sunlight off parts of the camera and its sun shade. From Voyager's great distance both Earth and Venus are mere points of light, less than the size of a picture element even in the narrow-angle camera. Earth was a crescent only 0.12 pixel in size. Coincidentally, Earth lies right in the center of one of the scattered light rays resulting from taking the image so close to the sun. Detailed analysis also suggests that Voyager detected the moon as well, but it is too faint to be seen without special processing. Venus was only 0.11 pixel in diameter. The faint colored structure in both planetary frames results from sunlight scattered in the optics.

Taming Pipelines, Users, and High Performance Computing with Rector

NASA Astrophysics Data System (ADS)

Estes, N. M.; Bowley, K. S.; Paris, K. N.; Silva, V. H.; Robinson, M. S.

2018-04-01

Rector is a high-performance job management system created by the LROC SOC team to enable processing of thousands of observations and ancillary data products as well as ad-hoc user jobs across a 634 CPU core processing cluster.

The Tactile Vision Substitution System: Applications in Education and Employment

ERIC Educational Resources Information Center

Scadden, Lawrence A.

1974-01-01

The Tactile Vision Substitution System converts the visual image from a narrow-angle television camera to a tactual image on a 5-inch square, 100-point display of vibrators placed against the abdomen of the blind person. (Author)

ARC-1990-AC79-7127

NASA Image and Video Library

1990-02-14

Range : 4 billion miles from Earth, at 32 degrees to the ecliptic. P-36057C This color image of the Sun, Earth, and Venus is one of the first, and maybe, only images that show are solar system from such a vantage point. The image is a portion of a wide angle image containing the sun and the region of space where the Earth and Venus were at the time, with narrow angle cameras centered on each planet. The wide angle was taken with the cameras darkest filter, a methane absorption band, and the shortest possible exposure, one two-hundredth of a second, to avoid saturating the camera's vidicon tube with scattered sunlight. The sun is not large in the sky, as seen from Voyager's perpective at the edge of the solar system. Yet, it is still 8xs brighter than the brightest star in Earth's sky, Sirius. The image of the sun you see is far larger than the actual dimension of the solar disk. The result of the brightness is a bright burned out image with multiple reflections from the optics of the camera. The rays around th sun are a diffraction pattern of the calibration lamp which is mounted in front of the wide angle lens. the 2 narrow angle frames containing the images of the Earth and Venus have been digitally mosaicked into the wide angle image at the appropriate scale. These images were taken through three color filters and recombined to produce the color image. The violet, green, and blue filters used , as well as exposure times of .72,.48, and .72 for Earth, and .36, .24, and .36 for Venus.The images also show long linear streaks resulting from scatering of sulight off parts of the camera and its shade.

Conditions that influence the accuracy of anthropometric parameter estimation for human body segments using shape-from-silhouette

NASA Astrophysics Data System (ADS)

Mundermann, Lars; Mundermann, Annegret; Chaudhari, Ajit M.; Andriacchi, Thomas P.

2005-01-01

Anthropometric parameters are fundamental for a wide variety of applications in biomechanics, anthropology, medicine and sports. Recent technological advancements provide methods for constructing 3D surfaces directly. Of these new technologies, visual hull construction may be the most cost-effective yet sufficiently accurate method. However, the conditions influencing the accuracy of anthropometric measurements based on visual hull reconstruction are unknown. The purpose of this study was to evaluate the conditions that influence the accuracy of 3D shape-from-silhouette reconstruction of body segments dependent on number of cameras, camera resolution and object contours. The results demonstrate that the visual hulls lacked accuracy in concave regions and narrow spaces, but setups with a high number of cameras reconstructed a human form with an average accuracy of 1.0 mm. In general, setups with less than 8 cameras yielded largely inaccurate visual hull constructions, while setups with 16 and more cameras provided good volume estimations. Body segment volumes were obtained with an average error of 10% at a 640x480 resolution using 8 cameras. Changes in resolution did not significantly affect the average error. However, substantial decreases in error were observed with increasing number of cameras (33.3% using 4 cameras; 10.5% using 8 cameras; 4.1% using 16 cameras; 1.2% using 64 cameras).

Photometric characterization of the Chang'e-3 landing site using LROC NAC images

NASA Astrophysics Data System (ADS)

Clegg-Watkins, R. N.; Jolliff, B. L.; Boyd, A.; Robinson, M. S.; Wagner, R.; Stopar, J. D.; Plescia, J. B.; Speyerer, E. J.

2016-07-01

China's robotic Chang'e-3 spacecraft, carrying the Yutu rover, touched down in Mare Imbrium on the lunar surface on 14 December 2013. The Lunar Reconnaissance Orbiter (LRO) Narrow Angle Camera (NAC) imaged the site both before and after landing. Multi-temporal NAC images taken before and after the landing, phase-ratio images made from NAC images taken after the landing, and Hapke photometric techniques were used to evaluate surface changes caused by the disturbance of regolith at the landing site (blast zone) by the descent engines of the Chang'e-3 spacecraft. The reflectance of the landing site increased by 10 ± 1% (from I/F = 0.040 to 0.044 at 30° phase angle) as a result of the landing, a value similar to reflectance increases estimated for the Apollo, Luna, and Surveyor landing sites. The spatial extent of the disturbed area at the Chang'e-3 landing site, 2530 m2, also falls close to what is predicted on the basis of correlations between lander mass, thrust, and blast zone areas for the historic landed missions. A multi-temporal ratio image of the Chang'e-3 landing site reveals a main blast zone (slightly elongate in the N-S direction; ∼75 m across N-S and ∼43 m across in the E-W direction) and an extended diffuse, irregular halo that is less reflective than the main blast zone (extending ∼40-50 m in the N-S direction and ∼10-15 m in the E-W direction beyond the main blast zone). The N-S elongation of the blast zone likely resulted from maneuvering during hazard avoidance just prior to landing. The phase-ratio image reveals that the blast zone is less backscattering than surrounding undisturbed areas. The similarities in magnitude of increased reflectance between the Chang'e-3 landing site and the Surveyor, Apollo, and Luna landing sites suggest that lunar soil reflectance changes caused by interaction with rocket exhaust are not significantly altered over a period of 40-50 years. The reflectance changes are independent of regolith composition, indicating that they are caused by a change in the physical properties of the regolith, likely microscopic to macroscopic smoothing of the surface, and possibly a change in surface maturity by removal of highly mature very fine-grained regolith components.

Neptune Through a Clear Filter

NASA Image and Video Library

1999-07-25

On July 23, 1989, NASA Voyager 2 spacecraft took this picture of Neptune through a clear filter on its narrow-angle camera. The image on the right has a latitude and longitude grid added for reference. Neptune Great Dark Spot is visible on the left.

AMES Stereo Pipeline Derived DEM Accuracy Experiment Using LROC-NAC Stereopairs and Weighted Spatial Dependence Simulation for Lunar Site Selection

NASA Astrophysics Data System (ADS)

Laura, J. R.; Miller, D.; Paul, M. V.

2012-03-01

An accuracy assessment of AMES Stereo Pipeline derived DEMs for lunar site selection using weighted spatial dependence simulation and a call for outside AMES derived DEMs to facilitate a statistical precision analysis.

Solar System Portrait - 60 Frame Mosaic

NASA Image and Video Library

1996-09-13

The cameras of Voyager 1 on Feb. 14, 1990, pointed back toward the sun and took a series of pictures of the sun and the planets, making the first ever portrait of our solar system as seen from the outside. In the course of taking this mosaic consisting of a total of 60 frames, Voyager 1 made several images of the inner solar system from a distance of approximately 4 billion miles and about 32 degrees above the ecliptic plane. Thirty-nine wide angle frames link together six of the planets of our solar system in this mosaic. Outermost Neptune is 30 times further from the sun than Earth. Our sun is seen as the bright object in the center of the circle of frames. The wide-angle image of the sun was taken with the camera's darkest filter (a methane absorption band) and the shortest possible exposure (5 thousandths of a second) to avoid saturating the camera's vidicon tube with scattered sunlight. The sun is not large as seen from Voyager, only about one-fortieth of the diameter as seen from Earth, but is still almost 8 million times brighter than the brightest star in Earth's sky, Sirius. The result of this great brightness is an image with multiple reflections from the optics in the camera. Wide-angle images surrounding the sun also show many artifacts attributable to scattered light in the optics. These were taken through the clear filter with one second exposures. The insets show the planets magnified many times. Narrow-angle images of Earth, Venus, Jupiter, Saturn, Uranus and Neptune were acquired as the spacecraft built the wide-angle mosaic. Jupiter is larger than a narrow-angle pixel and is clearly resolved, as is Saturn with its rings. Uranus and Neptune appear larger than they really are because of image smear due to spacecraft motion during the long (15 second) exposures. From Voyager's great distance Earth and Venus are mere points of light, less than the size of a picture element even in the narrow-angle camera. Earth was a crescent only 0.12 pixel in size. Coincidentally, Earth lies right in the center of one of the scattered light rays resulting from taking the image so close to the sun. http://photojournal.jpl.nasa.gov/catalog/PIA00451

Solar System Portrait - 60 Frame Mosaic

NASA Technical Reports Server (NTRS)

1990-01-01

The cameras of Voyager 1 on Feb. 14, 1990, pointed back toward the sun and took a series of pictures of the sun and the planets, making the first ever 'portrait' of our solar system as seen from the outside. In the course of taking this mosaic consisting of a total of 60 frames, Voyager 1 made several images of the inner solar system from a distance of approximately 4 billion miles and about 32 degrees above the ecliptic plane. Thirty-nine wide angle frames link together six of the planets of our solar system in this mosaic. Outermost Neptune is 30 times further from the sun than Earth. Our sun is seen as the bright object in the center of the circle of frames. The wide-angle image of the sun was taken with the camera's darkest filter (a methane absorption band) and the shortest possible exposure (5 thousandths of a second) to avoid saturating the camera's vidicon tube with scattered sunlight. The sun is not large as seen from Voyager, only about one-fortieth of the diameter as seen from Earth, but is still almost 8 million times brighter than the brightest star in Earth's sky, Sirius. The result of this great brightness is an image with multiple reflections from the optics in the camera. Wide-angle images surrounding the sun also show many artifacts attributable to scattered light in the optics. These were taken through the clear filter with one second exposures. The insets show the planets magnified many times. Narrow-angle images of Earth, Venus, Jupiter, Saturn, Uranus and Neptune were acquired as the spacecraft built the wide-angle mosaic. Jupiter is larger than a narrow-angle pixel and is clearly resolved, as is Saturn with its rings. Uranus and Neptune appear larger than they really are because of image smear due to spacecraft motion during the long (15 second) exposures. From Voyager's great distance Earth and Venus are mere points of light, less than the size of a picture element even in the narrow-angle camera. Earth was a crescent only 0.12 pixel in size. Coincidentally, Earth lies right in the center of one of the scattered light rays resulting from taking the image so close to the sun.

Photogrammetric measurement of 3D freeform millimetre-sized objects with micro features: an experimental validation of the close-range camera calibration model for narrow angles of view

NASA Astrophysics Data System (ADS)

Percoco, Gianluca; Sánchez Salmerón, Antonio J.

2015-09-01

The measurement of millimetre and micro-scale features is performed by high-cost systems based on technologies with narrow working ranges to accurately control the position of the sensors. Photogrammetry would lower the costs of 3D inspection of micro-features and would be applicable to the inspection of non-removable micro parts of large objects too. Unfortunately, the behaviour of photogrammetry is not known when photogrammetry is applied to micro-features. In this paper, the authors address these issues towards the application of digital close-range photogrammetry (DCRP) to the micro-scale, taking into account that in literature there are research papers stating that an angle of view (AOV) around 10° is the lower limit to the application of the traditional pinhole close-range calibration model (CRCM), which is the basis of DCRP. At first a general calibration procedure is introduced, with the aid of an open-source software library, to calibrate narrow AOV cameras with the CRCM. Subsequently the procedure is validated using a reflex camera with a 60 mm macro lens, equipped with extension tubes (20 and 32 mm) achieving magnification of up to 2 times approximately, to verify literature findings with experimental photogrammetric 3D measurements of millimetre-sized objects with micro-features. The limitation experienced by the laser printing technology, used to produce the bi-dimensional pattern on common paper, has been overcome using an accurate pattern manufactured with a photolithographic process. The results of the experimental activity prove that the CRCM is valid for AOVs down to 3.4° and that DCRP results are comparable with the results of existing and more expensive commercial techniques.

3d morphometric analysis of lunar impact craters: a tool for degradation estimates and interpretation of maria stratigraphy

NASA Astrophysics Data System (ADS)

Vivaldi, Valerio; Massironi, Matteo; Ninfo, Andrea; Cremonese, Gabriele

2015-04-01

In this study we have applied 3D morphometric analysis of impact craters on the Moon by means of high resolution DTMs derived from LROC (Lunar Reconnaissance Orbiter Camera) NAC (Narrow Angle Camera) (0.5 to 1.5 m/pixel). The objective is twofold: i) evaluating crater degradation and ii) exploring the potential of this approach for Maria stratigraphic interpretation. In relation to the first objective we have considered several craters with different diameters representative of the four classes of degradation being C1 the freshest and C4 the most degraded ones (Arthur et al., 1963; Wilhelms, 1987). DTMs of these craters were elaborated according to a multiscalar approach (Wood, 1996) by testing different ranges of kernel sizes (e.g. 15-35-50-75-100), in order to retrieve morphometric variables such as slope, curvatures and openness. In particular, curvatures were calculated along different planes (e.g. profile curvature and plan curvature) and used to characterize the different sectors of a crater (rim crest, floor, internal slope and related boundaries) enabling us to evaluate its degradation. The gradient of the internal slope of different craters representative of the four classes shows a decrease of the slope mean value from C1 to C4 in relation to crater age and diameter. Indeed degradation is influenced by gravitational processes (landslides, dry flows), as well as space weathering that induces both smoothing effects on the morphologies and infilling processes within the crater, with the main results of lowering and enlarging the rim crest, and shallowing the crater depth. As far as the stratigraphic application is concerned, morphometric analysis was applied to recognize morphologic features within some simple craters, in order to understand the stratigraphic relationships among different lava layers within Mare Serenitatis. A clear-cut rheological boundary at a depth of 200 m within the small fresh Linnè crater (diameter: 2.22 km), firstly hypothesized through numerical investigation (Martellato et al.), has been well identified as a bland morphological step on the inner crater scarp by using slope and curvature maps derived from a NAC DTM. In addition to this main morphological feature, other minor layers have been detected allowing to consider impact crater as stratigraphic logs to perform an interpretative subsurface map of a selected sector of Mare Serenitatis. References ARTHUR, D.W.G., AGNIERAY, A.P., HORVATH, R.A., WOOD, C.A. , CHAPMAN, C.R., 1963. The system of lunar craters. Quadrant I. Comm. Lunar Planet. Lab. 2, #30. MARTELLATO E., ROBINSON M.S., CREMONESE G. & LUCCHETTI A., 2013. Numerical modeling of Linné crater. EPSC Abstracts Vol. 8, EPSC2013-649. WILHELMS, D., 1987. The Geologic History of the Moon. US Geological Survey Professional Paper 1348. WOOD, J., 1996. The geomorphological characterization of digital elevation models. PhD Thesis, University of Leicester, UK.

Background correction in forensic photography. II. Photography of blood under conditions of non-uniform illumination or variable substrate color--practical aspects and limitations.

PubMed

Wagner, John H; Miskelly, Gordon M

2003-05-01

The combination of photographs taken at wavelengths at and bracketing the peak of a narrow absorbance band can lead to enhanced visualization of the substance causing the narrow absorbance band. This concept can be used to detect putative bloodstains by division of a linear photographic image taken at or near 415 nm with an image obtained by averaging linear photographs taken at or near 395 and 435 nm. Nonlinear images can also be background corrected by substituting subtraction for the division. This paper details experimental applications and limitations of this technique, including wavelength selection of the illuminant and at the camera. Characterization of a digital camera to be used in such a study is also detailed. Detection limits for blood using the three wavelength correction method under optimum conditions have been determined to be as low as 1 in 900 dilution, although on strongly patterned substrates blood diluted more than twenty-fold is difficult to detect. Use of only the 435 nm photograph to estimate the background in the 415 nm image lead to a twofold improvement in detection limit on unpatterned substrates compared with the three wavelength method with the particular camera and lighting system used, but it gave poorer background correction on patterned substrates.

Measurement of the surface wavelength distribution of narrow-band radiation by a colorimetric method

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kraiskii, A V; Mironova, T V; Sultanov, T T

2010-09-10

A method is suggested for determining the wavelength of narrow-band light from a digital photograph of a radiating surface. The digital camera used should be appropriately calibrated. The accuracy of the wavelength measurement is better than 1 nm. The method was tested on the yellow doublet of mercury spectrum and on the adjacent continuum of the incandescent lamp radiation spectrum. By means of the method suggested the homogeneity of holographic sensor swelling was studied in stationary and transient cases. (laser applications and other topics in quantum electronics)

LASER APPLICATIONS AND OTHER TOPICS IN QUANTUM ELECTRONICS: Measurement of the surface wavelength distribution of narrow-band radiation by a colorimetric method

NASA Astrophysics Data System (ADS)

Kraiskii, A. V.; Mironova, T. V.; Sultanov, T. T.

2010-09-01

A method is suggested for determining the wavelength of narrow-band light from a digital photograph of a radiating surface. The digital camera used should be appropriately calibrated. The accuracy of the wavelength measurement is better than 1 nm. The method was tested on the yellow doublet of mercury spectrum and on the adjacent continuum of the incandescent lamp radiation spectrum. By means of the method suggested the homogeneity of holographic sensor swelling was studied in stationary and transient cases.

Real-Time Visualization of Tissue Ischemia

NASA Technical Reports Server (NTRS)

Bearman, Gregory H. (Inventor); Chrien, Thomas D. (Inventor); Eastwood, Michael L. (Inventor)

2000-01-01

A real-time display of tissue ischemia which comprises three CCD video cameras, each with a narrow bandwidth filter at the correct wavelength is discussed. The cameras simultaneously view an area of tissue suspected of having ischemic areas through beamsplitters. The output from each camera is adjusted to give the correct signal intensity for combining with, the others into an image for display. If necessary a digital signal processor (DSP) can implement algorithms for image enhancement prior to display. Current DSP engines are fast enough to give real-time display. Measurement at three, wavelengths, combined into a real-time Red-Green-Blue (RGB) video display with a digital signal processing (DSP) board to implement image algorithms, provides direct visualization of ischemic areas.

Colors of active regions on comet 67P

NASA Astrophysics Data System (ADS)

Oklay, N.; Vincent, J.-B.; Sierks, H.; Besse, S.; Fornasier, S.; Barucci, M. A.; Lara, L.; Scholten, F.; Preusker, F.; Lazzarin, M.; Pajola, M.; La Forgia, F.

2015-10-01

The OSIRIS (Optical, Spectroscopic, and Infrared Remote Imaging System) scientific imager (Keller et al. 2007) is successfully delivering images of comet 67P/Churyumov-Gerasimenko from its both wide angle camera (WAC) and narrow angle camera (NAC) since ESA's spacecraft Rosetta's arrival to the comet. Both cameras are equipped with filters covering the wavelength range of about 200 nm to 1000 nm. The comet nucleus is mapped with different combination of the filters in resolutions up to 15 cm/px. Besides the determination of the surface morphology in great details (Thomas et al. 2015), such high resolution images provided us a mean to unambiguously link some activity in the coma to a series of pits on the nucleus surface (Vincent et al. 2015).

Lens and Camera Arrays for Sky Surveys and Space Surveillance

NASA Astrophysics Data System (ADS)

Ackermann, M.; Cox, D.; McGraw, J.; Zimmer, P.

2016-09-01

In recent years, a number of sky survey projects have chosen to use arrays of commercial cameras coupled with commercial photographic lenses to enable low-cost, wide-area observation. Projects such as SuperWASP, FAVOR, RAPTOR, Lotis, PANOPTES, and DragonFly rely on multiple cameras with commercial lenses to image wide areas of the sky each night. The sensors are usually commercial astronomical charge coupled devices (CCDs) or digital single reflex (DSLR) cameras, while the lenses are large-aperture, highend consumer items intended for general photography. While much of this equipment is very capable and relatively inexpensive, this approach comes with a number of significant limitations that reduce sensitivity and overall utility of the image data. The most frequently encountered limitations include lens vignetting, narrow spectral bandpass, and a relatively large point spread function. Understanding these limits helps to assess the utility of the data, and identify areas where advanced optical designs could significantly improve survey performance.

Ultra-fast framing camera tube

DOEpatents

Kalibjian, Ralph

1981-01-01

An electronic framing camera tube features focal plane image dissection and synchronized restoration of the dissected electron line images to form two-dimensional framed images. Ultra-fast framing is performed by first streaking a two-dimensional electron image across a narrow slit, thereby dissecting the two-dimensional electron image into sequential electron line images. The dissected electron line images are then restored into a framed image by a restorer deflector operated synchronously with the dissector deflector. The number of framed images on the tube's viewing screen is equal to the number of dissecting slits in the tube. The distinguishing features of this ultra-fast framing camera tube are the focal plane dissecting slits, and the synchronously-operated restorer deflector which restores the dissected electron line images into a two-dimensional framed image. The framing camera tube can produce image frames having high spatial resolution of optical events in the sub-100 picosecond range.

Still from Processed Movie of Zonal Jets

NASA Image and Video Library

2000-11-21

This image is one frame from a movie clip of cloud motions on Jupiter, from the side of the planet opposite to the Great Red Spot. It was taken in the first week of October 2000 by the narrow-angle camera on NASA Cassini spacecraft,

Global calibration of multi-cameras with non-overlapping fields of view based on photogrammetry and reconfigurable target

NASA Astrophysics Data System (ADS)

Xia, Renbo; Hu, Maobang; Zhao, Jibin; Chen, Songlin; Chen, Yueling

2018-06-01

Multi-camera vision systems are often needed to achieve large-scale and high-precision measurement because these systems have larger fields of view (FOV) than a single camera. Multiple cameras may have no or narrow overlapping FOVs in many applications, which pose a huge challenge to global calibration. This paper presents a global calibration method for multi-cameras without overlapping FOVs based on photogrammetry technology and a reconfigurable target. Firstly, two planar targets are fixed together and made into a long target according to the distance between the two cameras to be calibrated. The relative positions of the two planar targets can be obtained by photogrammetric methods and used as invariant constraints in global calibration. Then, the reprojection errors of target feature points in the two cameras’ coordinate systems are calculated at the same time and optimized by the Levenberg–Marquardt algorithm to find the optimal solution of the transformation matrix between the two cameras. Finally, all the camera coordinate systems are converted to the reference coordinate system in order to achieve global calibration. Experiments show that the proposed method has the advantages of high accuracy (the RMS error is 0.04 mm) and low cost and is especially suitable for on-site calibration.

2D Measurements of the Balmer Series in Proto-MPEX using a Fast Visible Camera Setup

NASA Astrophysics Data System (ADS)

Lindquist, Elizabeth G.; Biewer, Theodore M.; Ray, Holly B.

2017-10-01

The Prototype Material Plasma Exposure eXperiment (Proto-MPEX) is a linear plasma device with densities up to 1020 m-3 and temperatures up to 20 eV. Broadband spectral measurements show the visible emission spectra are solely due to the Balmer lines of deuterium. Monochromatic and RGB color Sanstreak SC1 Edgertronic fast visible cameras capture high speed video of plasmas in Proto-MPEX. The color camera is equipped with a long pass 450 nm filter and an internal Bayer filter to view the Dα line at 656 nm on the red channel and the Dβ line at 486 nm on the blue channel. The monochromatic camera has a 434 nm narrow bandpass filter to view the Dγ intensity. In the setup, a 50/50 beam splitter is used so both cameras image the same region of the plasma discharge. Camera images were aligned to each other by viewing a grid ensuring 1 pixel registration between the two cameras. A uniform intensity calibrated white light source was used to perform a pixel-to-pixel relative and an absolute intensity calibration for both cameras. Python scripts that combined the dual camera data, rendering the Dα, Dβ, and Dγ intensity ratios. Observations from Proto-MPEX discharges will be presented. This work was supported by the US. D.O.E. contract DE-AC05-00OR22725.

Spheres of Earth: An Introduction to Making Observations of Earth Using an Earth System's Science Approach. Student Guide

NASA Technical Reports Server (NTRS)

Graff, Paige Valderrama; Baker, Marshalyn (Editor); Graff, Trevor (Editor); Lindgren, Charlie (Editor); Mailhot, Michele (Editor); McCollum, Tim (Editor); Runco, Susan (Editor); Stefanov, William (Editor); Willis, Kim (Editor)

2010-01-01

Scientists from the Image Science and Analysis Laboratory (ISAL) at NASA's Johnson Space Center (JSC) work with astronauts onboard the International Space Station (ISS) who take images of Earth. Astronaut photographs, sometimes referred to as Crew Earth Observations, are taken using hand-held digital cameras onboard the ISS. These digital images allow scientists to study our Earth from the unique perspective of space. Astronauts have taken images of Earth since the 1960s. There is a database of over 900,000 astronaut photographs available at http://eol.jsc.nasa.gov . Images are requested by ISAL scientists at JSC and astronauts in space personally frame and acquire them from the Destiny Laboratory or other windows in the ISS. By having astronauts take images, they can specifically frame them according to a given request and need. For example, they can choose to use different lenses to vary the amount of area (field of view) an image will cover. Images can be taken at different times of the day which allows different lighting conditions to bring out or highlight certain features. The viewing angle at which an image is acquired can also be varied to show the same area from different perspectives. Pointing the camera straight down gives you a nadir shot. Pointing the camera at an angle to get a view across an area would be considered an oblique shot. Being able to change these variables makes astronaut photographs a unique and useful data set. Astronaut photographs are taken from the ISS from altitudes of 300 - 400 km (185 to 250 miles). One of the current cameras being used, the Nikon D3X digital camera, can take images using a 50, 100, 250, 400 or 800mm lens. These different lenses allow for a wider or narrower field of view. The higher the focal length (800mm for example) the narrower the field of view (less area will be covered). Higher focal lengths also show greater detail of the area on the surface being imaged. Scientists from the Image Science and Analysis Laboratory (ISAL) at NASA s Johnson Space Center (JSC) work with astronauts onboard the International Space Station (ISS) who take images of Earth. Astronaut photographs, sometimes referred to as Crew Earth Observations, are taken using hand-held digital cameras onboard the ISS. These digital images allow scientists to study our Earth from the unique perspective of space. Astronauts have taken images of Earth since the 1960s. There is a database of over 900,000 astronaut photographs available at http://eol.jsc.nasa.gov . Images are requested by ISAL scientists at JSC and astronauts in space personally frame and acquire them from the Destiny Laboratory or other windows in the ISS. By having astronauts take images, they can specifically frame them according to a given request and need. For example, they can choose to use different lenses to vary the amount of area (field of view) an image will cover. Images can be taken at different times of the day which allows different lighting conditions to bring out or highlight certain features. The viewing angle at which an image is acquired can also be varied to show the same area from different perspectives. Pointing the camera straight down gives you a nadir shot. Pointing the camera at an angle to get a view across an area would be considered an oblique shot. Being able to change these variables makes astronaut photographs a unique and useful data set. Astronaut photographs are taken from the ISS from altitudes of 300 - 400 km (approx.185 to 250 miles). One of the current cameras being used, the Nikon D3X digital camera, can take images using a 50, 100, 250, 400 or 800mm lens. These different lenses allow for a wider or narrower field of view. The higher the focal length (800mm for example) the narrower the field of view (less area will be covered). Higher focal lengths also show greater detail of the area on the surface being imaged. There are four major systems or spheres of Earth. They are: Atmosphere, Biosphere, Hydrosphe, and Litho/Geosphere.

Novel 3D imaging techniques for improved understanding of planetary surface geomorphology.

NASA Astrophysics Data System (ADS)

Muller, Jan-Peter

2015-04-01

Understanding the role of different planetary surface formation processes within our Solar System is one of the fundamental goals of planetary science research. There has been a revolution in planetary surface observations over the past decade for Mars and the Moon, especially in 3D imaging of surface shape (down to resolutions of 75cm) and subsequent correction for terrain relief of imagery from orbiting and co-registration of lander and rover robotic images. We present some of the recent highlights including 3D modelling of surface shape from the ESA Mars Express HRSC (High Resolution Stereo Camera), see [1], [2] at 30-100m grid-spacing; and then co-registered to HRSC using a resolution cascade of 20m DTMs from NASA MRO stereo-CTX and 0.75m DTMs from MRO stereo-HiRISE [3]. This has opened our eyes to the formation mechanisms of megaflooding events, such as the formation of Iani Vallis and the upstream blocky terrain, to crater lakes and receding valley cuts [4]. A comparable set of products is now available for the Moon from LROC-WA at 100m [5] and LROC-NA at 1m [6]. Recently, a very novel technique for the super-resolution restoration (SRR) of stacks of images has been developed at UCL [7]. First examples shown will be of the entire MER-A Spirit rover traverse taking a stack of 25cm HiRISE to generate a corridor of SRR images along the rover traverse of 5cm imagery of unresolved features such as rocks, created as a consequence of meteoritic bombardment, ridge and valley features. This SRR technique will allow us for ˜400 areas on Mars (where 5 or more HiRISE images have been captured) and similar numbers on the Moon to resolve sub-pixel features. Examples will be shown of how these SRR images can be employed to assist with the better understanding of surface geomorphology. Acknowledgements: The research leading to these results has received funding from the European Union's Seventh Framework Programme (FP7/2007-2013) under PRoViDE grant agreement n° 312377. Partial support is also provided from the STFC 'MSSL Consolidated Grant' ST/K000977/1. References: [1] Gwinner, K., F. et al. (2010) Topography of Mars from global mapping by HRSC high-resolution digital terrain models and orthoimages: characteristics and performance. Earth and Planetary Science Letters 294, 506-519, doi:10.1016/j.epsl.2009.11.007, 2010; [2] Gwinner, K., F. et al. (2015) MarsExpress High Resolution Stereo Camera (HRSC) Multi-orbit Data Products: Methodology, Mapping Concepts and Performance for the first Quadrangle (MC-11E). Geophysical Research Abstracts, Vol. 17, EGU2015-13832; [3] Kim, J., & Muller, J. (2009). Multi-resolution topographic data extraction from Martian stereo imagery. Planetary and Space Science, 57, 2095-2112. doi:10.1016/j.pss.2009.09.024; [4] Warner, N. H., Gupta, S., Kim, J.-R., Muller, J.-P., Le Corre, L., Morley, J., et al. (2011). Constraints on the origin and evolution of Iani Chaos, Mars. Journal of Geophysical Research, 116(E6), E06003. doi:10.1029/2010JE003787; [5] Fok, H. S., Shum, C. K., Yi, Y., Araki, H., Ping, J., Williams, J. G., et al. (2011). Accuracy assessment of lunar topography models. Earth Planets Space, 63, 15-23. doi:10.5047/eps.2010.08.005; [6] Haase, I., Oberst, J., Scholten, F., Wählisch, M., Gläser, P., Karachevtseva, I., & Robinson, M. S. (2012). Mapping the Apollo 17 landing site area based on Lunar Reconnaissance Orbiter Camera images and Apollo surface photography - Haase - 2012 - Journal of Geophysical Research: Planets (1991-2012). Journal of Geophysical Research, 117, E00H20. doi:10.1029/2011JE003908; [7] Tao, Y., Muller, J.-P. (2015) Supporting lander and rover operation: a novel super-resolution restoration technique. Geophysical Research Abstracts, Vol. 17, EGU2015-6925

Characterization and performance of PAUCam filters

NASA Astrophysics Data System (ADS)

Casas, R.; Cardiel-Sas, L.; Castander, F. J.; Díaz, C.; Gaweda, J.; Jiménez Rojas, J.; Jiménez, S.; Lamensans, M.; Padilla, C.; Rodriguez, F. J.; Sanchez, E.; Sevilla Noarbe, I.

2016-08-01

PAUCam is a large field of view camera designed to exploit the field delivered by the prime focus corrector of the William Herschel Telescope, at the Observatorio del Roque de los Muchachos. One of the new features of this camera is its filter system, placed within a few millimeters of the focal plane using eleven trays containing 40 narrow band and 6 broad band filters, working in vacuum at an operational temperature of 250K and in a focalized beam. In this contribution, we describe the performance of these filters both in the characterization tests at the laboratory.

Volume three-dimensional flow measurements using wavelength multiplexing.

PubMed

Moore, Andrew J; Smith, Jason; Lawson, Nicholas J

2005-10-01

Optically distinguishable seeding particles that emit light in a narrow bandwidth, and a combination of bandwidths, were prepared by encapsulating quantum dots. The three-dimensional components of the particles' displacement were measured within a volume of fluid with particle tracking velocimetry (PTV). Particles are multiplexed to different hue bands in the camera images, enabling an increased seeding density and (or) fewer cameras to be used, thereby increasing the measurement spatial resolution and (or) reducing optical access requirements. The technique is also applicable to two-phase flow measurements with PTV or particle image velocimetry, where each phase is uniquely seeded.

InfraCAM (trade mark): A Hand-Held Commercial Infrared Camera Modified for Spaceborne Applications

NASA Technical Reports Server (NTRS)

Manitakos, Daniel; Jones, Jeffrey; Melikian, Simon

1996-01-01

In 1994, Inframetrics introduced the InfraCAM(TM), a high resolution hand-held thermal imager. As the world's smallest, lightest and lowest power PtSi based infrared camera, the InfraCAM is ideal for a wise range of industrial, non destructive testing, surveillance and scientific applications. In addition to numerous commercial applications, the light weight and low power consumption of the InfraCAM make it extremely valuable for adaptation to space borne applications. Consequently, the InfraCAM has been selected by NASA Lewis Research Center (LeRC) in Cleveland, Ohio, for use as part of the DARTFire (Diffusive and Radiative Transport in Fires) space borne experiment. In this experiment, a solid fuel is ignited in a low gravity environment. The combustion period is recorded by both visible and infrared cameras. The infrared camera measures the emission from polymethyl methacrylate, (PMMA) and combustion products in six distinct narrow spectral bands. Four cameras successfully completed all qualification tests at Inframetrics and at NASA Lewis. They are presently being used for ground based testing in preparation for space flight in the fall of 1995.

Acquisition and visualization techniques for narrow spectral color imaging.

PubMed

Neumann, László; García, Rafael; Basa, János; Hegedüs, Ramón

2013-06-01

This paper introduces a new approach in narrow-band imaging (NBI). Existing NBI techniques generate images by selecting discrete bands over the full visible spectrum or an even wider spectral range. In contrast, here we perform the sampling with filters covering a tight spectral window. This image acquisition method, named narrow spectral imaging, can be particularly useful when optical information is only available within a narrow spectral window, such as in the case of deep-water transmittance, which constitutes the principal motivation of this work. In this study we demonstrate the potential of the proposed photographic technique on nonunderwater scenes recorded under controlled conditions. To this end three multilayer narrow bandpass filters were employed, which transmit at 440, 456, and 470 nm bluish wavelengths, respectively. Since the differences among the images captured in such a narrow spectral window can be extremely small, both image acquisition and visualization require a novel approach. First, high-bit-depth images were acquired with multilayer narrow-band filters either placed in front of the illumination or mounted on the camera lens. Second, a color-mapping method is proposed, using which the input data can be transformed onto the entire display color gamut with a continuous and perceptually nearly uniform mapping, while ensuring optimally high information content for human perception.

Can we Use Low-Cost 360 Degree Cameras to Create Accurate 3d Models?

NASA Astrophysics Data System (ADS)

Barazzetti, L.; Previtali, M.; Roncoroni, F.

2018-05-01

360 degree cameras capture the whole scene around a photographer in a single shot. Cheap 360 cameras are a new paradigm in photogrammetry. The camera can be pointed to any direction, and the large field of view reduces the number of photographs. This paper aims to show that accurate metric reconstructions can be achieved with affordable sensors (less than 300 euro). The camera used in this work is the Xiaomi Mijia Mi Sphere 360, which has a cost of about 300 USD (January 2018). Experiments demonstrate that millimeter-level accuracy can be obtained during the image orientation and surface reconstruction steps, in which the solution from 360° images was compared to check points measured with a total station and laser scanning point clouds. The paper will summarize some practical rules for image acquisition as well as the importance of ground control points to remove possible deformations of the network during bundle adjustment, especially for long sequences with unfavorable geometry. The generation of orthophotos from images having a 360° field of view (that captures the entire scene around the camera) is discussed. Finally, the paper illustrates some case studies where the use of a 360° camera could be a better choice than a project based on central perspective cameras. Basically, 360° cameras become very useful in the survey of long and narrow spaces, as well as interior areas like small rooms.

Comparison of myocardial perfusion imaging between the new high-speed gamma camera and the standard anger camera.

PubMed

Tanaka, Hirokazu; Chikamori, Taishiro; Hida, Satoshi; Uchida, Kenji; Igarashi, Yuko; Yokoyama, Tsuyoshi; Takahashi, Masaki; Shiba, Chie; Yoshimura, Mana; Tokuuye, Koichi; Yamashina, Akira

2013-01-01

Cadmium-zinc-telluride (CZT) solid-state detectors have been recently introduced into the field of myocardial perfusion imaging. The aim of this study was to prospectively compare the diagnostic performance of the CZT high-speed gamma camera (Discovery NM 530c) with that of the standard 3-head gamma camera in the same group of patients. The study group consisted of 150 consecutive patients who underwent a 1-day stress-rest (99m)Tc-sestamibi or tetrofosmin imaging protocol. Image acquisition was performed first on a standard gamma camera with a 15-min scan time each for stress and for rest. All scans were immediately repeated on a CZT camera with a 5-min scan time for stress and a 3-min scan time for rest, using list mode. The correlations between the CZT camera and the standard camera for perfusion and function analyses were strong within narrow Bland-Altman limits of agreement. Using list mode analysis, image quality for stress was rated as good or excellent in 97% of the 3-min scans, and in 100% of the ≥4-min scans. For CZT scans at rest, similarly, image quality was rated as good or excellent in 94% of the 1-min scans, and in 100% of the ≥2-min scans. The novel CZT camera provides excellent image quality, which is equivalent to standard myocardial single-photon emission computed tomography, despite a short scan time of less than half of the standard time.

Alpha and Omega

NASA Image and Video Library

2017-11-27

These two images illustrate just how far Cassini traveled to get to Saturn. On the left is one of the earliest images Cassini took of the ringed planet, captured during the long voyage from the inner solar system. On the right is one of Cassini's final images of Saturn, showing the site where the spacecraft would enter the atmosphere on the following day. In the left image, taken in 2001, about six months after the spacecraft passed Jupiter for a gravity assist flyby, the best view of Saturn using the spacecraft's high-resolution (narrow-angle) camera was on the order of what could be seen using the Earth-orbiting Hubble Space Telescope. At the end of the mission (at right), from close to Saturn, even the lower resolution (wide-angle) camera could capture just a tiny part of the planet. The left image looks toward Saturn from 20 degrees below the ring plane and was taken on July 13, 2001 in wavelengths of infrared light centered at 727 nanometers using the Cassini spacecraft narrow-angle camera. The view at right is centered on a point 6 degrees north of the equator and was taken in visible light using the wide-angle camera on Sept. 14, 2017. The view on the left was acquired at a distance of approximately 317 million miles (510 million kilometers) from Saturn. Image scale is about 1,900 miles (3,100 kilometers) per pixel. The view at right was acquired at a distance of approximately 360,000 miles (579,000 kilometers) from Saturn. Image scale is 22 miles (35 kilometers) per pixel. The Cassini spacecraft ended its mission on Sept. 15, 2017. https://photojournal.jpl.nasa.gov/catalog/PIA21353

Stereoscopic determination of all-sky altitude map of aurora using two ground-based Nikon DSLR cameras

NASA Astrophysics Data System (ADS)

Kataoka, R.; Miyoshi, Y.; Shigematsu, K.; Hampton, D.; Mori, Y.; Kubo, T.; Yamashita, A.; Tanaka, M.; Takahei, T.; Nakai, T.; Miyahara, H.; Shiokawa, K.

2013-09-01

A new stereoscopic measurement technique is developed to obtain an all-sky altitude map of aurora using two ground-based digital single-lens reflex (DSLR) cameras. Two identical full-color all-sky cameras were set with an 8 km separation across the Chatanika area in Alaska (Poker Flat Research Range and Aurora Borealis Lodge) to find localized emission height with the maximum correlation of the apparent patterns in the localized pixels applying a method of the geographical coordinate transform. It is found that a typical ray structure of discrete aurora shows the broad altitude distribution above 100 km, while a typical patchy structure of pulsating aurora shows the narrow altitude distribution of less than 100 km. Because of its portability and low cost of the DSLR camera systems, the new technique may open a unique opportunity not only for scientists but also for night-sky photographers to complementarily attend the aurora science to potentially form a dense observation network.

Automatic helmet-wearing detection for law enforcement using CCTV cameras

NASA Astrophysics Data System (ADS)

Wonghabut, P.; Kumphong, J.; Satiennam, T.; Ung-arunyawee, R.; Leelapatra, W.

2018-04-01

The objective of this research is to develop an application for enforcing helmet wearing using CCTV cameras. The developed application aims to help law enforcement by police, and eventually resulting in changing risk behaviours and consequently reducing the number of accidents and its severity. Conceptually, the application software implemented using C++ language and OpenCV library uses two different angle of view CCTV cameras. Video frames recorded by the wide-angle CCTV camera are used to detect motorcyclists. If any motorcyclist without helmet is found, then the zoomed (narrow-angle) CCTV is activated to capture image of the violating motorcyclist and the motorcycle license plate in real time. Captured images are managed by database implemented using MySQL for ticket issuing. The results show that the developed program is able to detect 81% of motorcyclists on various motorcycle types during daytime and night-time. The validation results reveal that the program achieves 74% accuracy in detecting the motorcyclist without helmet.

Faint F Ring and Prometheus

NASA Image and Video Library

2016-11-21

Surface features are visible on Saturn's moon Prometheus in this view from NASA's Cassini spacecraft. Most of Cassini's images of Prometheus are too distant to resolve individual craters, making views like this a rare treat. Saturn's narrow F ring, which makes a diagonal line beginning at top center, appears bright and bold in some Cassini views, but not here. Since the sun is nearly behind Cassini in this image, most of the light hitting the F ring is being scattered away from the camera, making it appear dim. Light-scattering behavior like this is typical of rings comprised of small particles, such as the F ring. This view looks toward the unilluminated side of the rings from about 14 degrees below the ring plane. The image was taken in visible light with the Cassini spacecraft narrow-angle camera on Sept. 24, 2016. The view was acquired at a distance of approximately 226,000 miles (364,000 kilometers) from Prometheus and at a sun-Prometheus-spacecraft, or phase, angle of 51 degrees. Image scale is 1.2 miles (2 kilometers) per pixel. http://photojournal.jpl.nasa.gov/catalog/PIA20508

VizieR Online Data Catalog: Spectroscopy of luminous compact blue galaxies (Crawford+, 2016)

NASA Astrophysics Data System (ADS)

Crawford, S. M.; Wirth, G. D.; Bershady, M. A.; Randriamampandry, S. M.

2017-10-01

Deep imaging data in UBRIz and two narrow bands were obtained with the Mini-Mosaic camera from the WIYN 3.5 m telescope for all five clusters between 1999 October and 2004 June. We obtained spectroscopic observations for a sample of cluster star-forming galaxies with the DEIMOS, Faber et al. 2003 on the Keck II Telescope during 2005 October and 2007 April. The narrow-band filters were specifically designed to detect [OII] λ3727 at the redshift of each cluster. All of the clusters have been the target of extensive observations with the HST, primarily using either WFPC2 or the Advanced Camera for Surveys (ACS). For all measurements, we have attempted to select data taken in a filter closest to the rest-frame B band. We have employed ACS imaging data whenever possible and substituted WFPC2 images only when required. For clusters observed in the far-infrared regime by the Spitzer Space Telescope, we extracted MIPS 24μm flux densities, S24, from images obtained through the Enhanced Imaging Products archive. (2 data files).

Correlation between model observer and human observer performance in CT imaging when lesion location is uncertain

DOE Office of Scientific and Technical Information (OSTI.GOV)

Leng, Shuai; Yu, Lifeng; Zhang, Yi

2013-08-15

Purpose: The purpose of this study was to investigate the correlation between model observer and human observer performance in CT imaging for the task of lesion detection and localization when the lesion location is uncertain.Methods: Two cylindrical rods (3-mm and 5-mm diameters) were placed in a 35 × 26 cm torso-shaped water phantom to simulate lesions with −15 HU contrast at 120 kV. The phantom was scanned 100 times on a 128-slice CT scanner at each of four dose levels (CTDIvol = 5.7, 11.4, 17.1, and 22.8 mGy). Regions of interest (ROIs) around each lesion were extracted to generate imagesmore » with signal-present, with each ROI containing 128 × 128 pixels. Corresponding ROIs of signal-absent images were generated from images without lesion mimicking rods. The location of the lesion (rod) in each ROI was randomly distributed by moving the ROIs around each lesion. Human observer studies were performed by having three trained observers identify the presence or absence of lesions, indicating the lesion location in each image and scoring confidence for the detection task on a 6-point scale. The same image data were analyzed using a channelized Hotelling model observer (CHO) with Gabor channels. Internal noise was added to the decision variables for the model observer study. Area under the curve (AUC) of ROC and localization ROC (LROC) curves were calculated using a nonparametric approach. The Spearman's rank order correlation between the average performance of the human observers and the model observer performance was calculated for the AUC of both ROC and LROC curves for both the 3- and 5-mm diameter lesions.Results: In both ROC and LROC analyses, AUC values for the model observer agreed well with the average values across the three human observers. The Spearman's rank order correlation values for both ROC and LROC analyses for both the 3- and 5-mm diameter lesions were all 1.0, indicating perfect rank ordering agreement of the figures of merit (AUC) between the average performance of the human observers and the model observer performance.Conclusions: In CT imaging of different sizes of low-contrast lesions (−15 HU), the performance of CHO with Gabor channels was highly correlated with human observer performance for the detection and localization tasks with uncertain lesion location in CT imaging at four clinically relevant dose levels. This suggests the ability of Gabor CHO model observers to meaningfully assess CT image quality for the purpose of optimizing scan protocols and radiation dose levels in detection and localization tasks for low-contrast lesions.« less

New Moon

NASA Image and Video Library

2017-12-08

New Moon. By the modern definition, New Moon occurs when the Moon and Sun are at the same geocentric ecliptic longitude. The part of the Moon facing us is completely in shadow then. Pictured here is the traditional New Moon, the earliest visible waxing crescent, which signals the start of a new month in many lunar and lunisolar calendars. NASA's Lunar Reconnaissance Orbiter (LRO) has been in orbit around the Moon since the summer of 2009. Its laser altimeter (LOLA) and camera (LROC) are recording the rugged, airless lunar terrain in exceptional detail, making it possible to visualize the Moon with unprecedented fidelity. This is especially evident in the long shadows cast near the terminator, or day-night line. The pummeled, craggy landscape thrown into high relief at the terminator would be impossible to recreate in the computer without global terrain maps like those from LRO. To download, learn more about this visualization, or to see what the Moon will look like at any hour in 2015, visit svs.gsfc.nasa.gov/goto?4236 NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

Photometric Characteristics of Lunar Terrains

NASA Astrophysics Data System (ADS)

Sato, Hiroyuki; Hapke, Bruce W.; Denevi, Brett W.; Robinson, Mark

2016-10-01

The photometric properties of the lunar depend on albedo, surface roughness, porosity, and the internal/external structure of particles. Hapke parameter maps derived using a bidirectional reflectance model [Hapke, 2012] from Lunar Reconnaissance Orbiter Camera (LROC) Wide Angle Camera (WAC) images demonstrated the spatial and spectral variation of the photometric properties of the Moon [Sato et al., 2014]. Using the same methodology, here we present the photometric characteristics of typical lunar terrains, which were not systematically analyzed in the previous study.We selected five representative terrain types: mare, highland, swirls, and two Copernican (fresh) crater ejecta (one mare and one highlands example). As for the datasets, we used ~39 months of WAC repeated observations, and for each image pixel, we computed latitude, longitude, incidence, emission, and phase angles using the WAC GLD100 stereo DTM [Scholten et al., 2012]. To obtain similar phase and incidence angle ranges, all sampling sites are near the equator and in the vicinity of Reiner Gamma. Three free Hapke parameters (single scattering albedo: w, HG2 phase function parameter: c, and angular width of SHOE: hs) were then calculated for the seven bands (321-689 nm). The remaining parameters were fixed by simplifying the model [Sato et al., 2014].The highlands, highland ejecta, and swirl (Reiner Gamma) showed clearly higher w than the mare and mare ejecta. The derived c values were lower (less backscattering) for the swirl and higher (more backscattering) for the highlands (and ejecta) relative to the other sites. Forward scattering materials such as unconsolidated transparent crystalline materials might be relatively enriched in the swirl. In the highlands, anorthositic agglutinates with dense internal scattering could be responsible for the strong backscattering. The mare and mare ejecta showed continuously decreasing c from UV to visible wavelengths. This might be caused by the FeO-rich pyroxene and glass in the mare becoming more translucent at longer wavelengths.

Formulation of image quality prediction criteria for the Viking lander camera

NASA Technical Reports Server (NTRS)

Huck, F. O.; Jobson, D. J.; Taylor, E. J.; Wall, S. D.

1973-01-01

Image quality criteria are defined and mathematically formulated for the prediction computer program which is to be developed for the Viking lander imaging experiment. The general objective of broad-band (black and white) imagery to resolve small spatial details and slopes is formulated as the detectability of a right-circular cone with surface properties of the surrounding terrain. The general objective of narrow-band (color and near-infrared) imagery to observe spectral characteristics if formulated as the minimum detectable albedo variation. The general goal to encompass, but not exceed, the range of the scene radiance distribution within single, commandable, camera dynamic range setting is also considered.

Laser line scan underwater imaging by complementary metal-oxide-semiconductor camera

NASA Astrophysics Data System (ADS)

He, Zhiyi; Luo, Meixing; Song, Xiyu; Wang, Dundong; He, Ning

2017-12-01

This work employs the complementary metal-oxide-semiconductor (CMOS) camera to acquire images in a scanning manner for laser line scan (LLS) underwater imaging to alleviate backscatter impact of seawater. Two operating features of the CMOS camera, namely the region of interest (ROI) and rolling shutter, can be utilized to perform image scan without the difficulty of translating the receiver above the target as the traditional LLS imaging systems have. By the dynamically reconfigurable ROI of an industrial CMOS camera, we evenly divided the image into five subareas along the pixel rows and then scanned them by changing the ROI region automatically under the synchronous illumination by the fun beams of the lasers. Another scanning method was explored by the rolling shutter operation of the CMOS camera. The fun beam lasers were turned on/off to illuminate the narrow zones on the target in a good correspondence to the exposure lines during the rolling procedure of the camera's electronic shutter. The frame synchronization between the image scan and the laser beam sweep may be achieved by either the strobe lighting output pulse or the external triggering pulse of the industrial camera. Comparison between the scanning and nonscanning images shows that contrast of the underwater image can be improved by our LLS imaging techniques, with higher stability and feasibility than the mechanically controlled scanning method.

Photometric normalization of LROC WAC images

NASA Astrophysics Data System (ADS)

Sato, H.; Denevi, B.; Robinson, M. S.; Hapke, B. W.; McEwen, A. S.; LROC Science Team

2010-12-01

The Lunar Reconnaissance Orbiter Camera (LROC) Wide Angle Camera (WAC) acquires near global coverage on a monthly basis. The WAC is a push frame sensor with a 90° field of view (FOV) in BW mode and 60° FOV in 7-color mode (320 nm to 689 nm). WAC images are acquired during each orbit in 10° latitude segments with cross track coverage of ~50 km. Before mosaicking, WAC images are radiometrically calibrated to remove instrumental artifacts and to convert at sensor radiance to I/F. Images are also photometrically normalized to common viewing and illumination angles (30° phase), a challenge due to the wide angle nature of the WAC where large differences in phase angle are observed in a single image line (±30°). During a single month the equatorial incidence angle drifts about 28° and over the course of ~1 year the lighting completes a 360° cycle. The light scattering properties of the lunar surface depend on incidence(i), emission(e), and phase(p) angles as well as soil properties such as single-scattering albedo and roughness that vary with terrain type and state of maturity [1]. We first tested a Lommel-Seeliger Correction (LSC) [cos(i)/(cos(i) + cos(e))] [2] with a phase function defined by an exponential decay plus 4th order polynomial term [3] which did not provide an adequate solution. Next we employed a LSC with an exponential 2nd order decay phase correction that was an improvement, but still exhibited unacceptable frame-to-frame residuals. In both cases we fitted the LSC I/F vs. phase angle to derive the phase corrections. To date, the best results are with a lunar-lambert function [4] with exponential 2nd order decay phase correction (LLEXP2) [(A1exp(B1p)+A2exp(B2p)+A3) * cos(i)/(cos(e) + cos(i)) + B3cos(i)]. We derived the parameters for the LLEXP2 from repeat imaging of a small region and then corrected that region with excellent results. When this correction was applied to the whole Moon the results were less than optimal - no surprise given the variability of the regolith from region to region. As the fitting area increases, the accuracy of curve fitting decreases due to the larger variety of albedo, topography, and composition. Thus we have adopted an albedo-dependent photometric normalization routine. Phase curves are derived for discreet bins of preliminary normalized reflectance calculated from Clementine global mosaic in a fitting area that is composed of predominantly mare in Oceanus Procellarum. The global WAC mosaic was then corrected pixel-by-pixel according to its preliminary reflectance map with satisfactory results. We observed that the phase curves per normalized-reflectance bins become steeper as the reflectance value increases. Further filtering by using FeO, TiO2, or optical maturity [5] for parameter calculations may help elucidate the effects of surface composition and maturity on photometric properties of the surface. [1] Hapke, B.W. (1993) Theory of Reflectance and Emittance Spectroscopy, Cambridge Univ. Press. [2] Schoenberg (1925) Ada. Soc. Febb., vol. 50. [3] Hillier et al. (1999) Icarus 141, 205-225. [4] McEwen (1991) Icarus 92, 298-311. [5] Lucey et al. (2000) JGR, v105, no E8, p20377-20386.

Multi-scale Characterization and Modeling of Surface Slope Probability Distribution for ~20-km Diameter Lunar Craters

NASA Astrophysics Data System (ADS)

Mahanti, P.; Robinson, M. S.; Boyd, A. K.

2013-12-01

Craters ~20-km diameter and above significantly shaped the lunar landscape. The statistical nature of the slope distribution on their walls and floors dominate the overall slope distribution statistics for the lunar surface. Slope statistics are inherently useful for characterizing the current topography of the surface, determining accurate photometric and surface scattering properties, and in defining lunar surface trafficability [1-4]. Earlier experimental studies on the statistical nature of lunar surface slopes were restricted either by resolution limits (Apollo era photogrammetric studies) or by model error considerations (photoclinometric and radar scattering studies) where the true nature of slope probability distribution was not discernible at baselines smaller than a kilometer[2,3,5]. Accordingly, historical modeling of lunar surface slopes probability distributions for applications such as in scattering theory development or rover traversability assessment is more general in nature (use of simple statistical models such as the Gaussian distribution[1,2,5,6]). With the advent of high resolution, high precision topographic models of the Moon[7,8], slopes in lunar craters can now be obtained at baselines as low as 6-meters allowing unprecedented multi-scale (multiple baselines) modeling possibilities for slope probability distributions. Topographic analysis (Lunar Reconnaissance Orbiter Camera (LROC) Narrow Angle Camera (NAC) 2-m digital elevation models (DEM)) of ~20-km diameter Copernican lunar craters revealed generally steep slopes on interior walls (30° to 36°, locally exceeding 40°) over 15-meter baselines[9]. In this work, we extend the analysis from a probability distribution modeling point-of-view with NAC DEMs to characterize the slope statistics for the floors and walls for the same ~20-km Copernican lunar craters. The difference in slope standard deviations between the Gaussian approximation and the actual distribution (2-meter sampling) was computed over multiple scales. This slope analysis showed that local slope distributions are non-Gaussian for both crater walls and floors. Over larger baselines (~100 meters), crater wall slope probability distributions do approximate Gaussian distributions better, but have long distribution tails. Crater floor probability distributions however, were always asymmetric (for the baseline scales analyzed) and less affected by baseline scale variations. Accordingly, our results suggest that use of long tailed probability distributions (like Cauchy) and a baseline-dependant multi-scale model can be more effective in describing the slope statistics for lunar topography. Refrences: [1]Moore, H.(1971), JGR,75(11) [2]Marcus, A. H.(1969),JGR,74 (22).[3]R.J. Pike (1970),U.S. Geological Survey Working Paper [4]N. C. Costes, J. E. Farmer and E. B. George (1972),NASA Technical Report TR R-401 [5]M. N. Parker and G. L. Tyler(1973), Radio Science, 8(3),177-184 [6]Alekseev, V. A.et al (1968), Soviet Astronomy, Vol. 11, p.860 [7]Burns et al. (2012) Int. Arch. Photogramm. Remote Sens. Spatial Inf. Sci., XXXIX-B4, 483-488.[8]Smith et al. (2010) GRL 37, L18204, DOI: 10.1029/2010GL043751. [9]Wagner R., Robinson, M., Speyerer E., Mahanti, P., LPSC 2013, #2924.

Setup for testing cameras for image guided surgery using a controlled NIR fluorescence mimicking light source and tissue phantom

NASA Astrophysics Data System (ADS)

Georgiou, Giota; Verdaasdonk, Rudolf M.; van der Veen, Albert; Klaessens, John H.

2017-02-01

In the development of new near-infrared (NIR) fluorescence dyes for image guided surgery, there is a need for new NIR sensitive camera systems that can easily be adjusted to specific wavelength ranges in contrast the present clinical systems that are only optimized for ICG. To test alternative camera systems, a setup was developed to mimic the fluorescence light in a tissue phantom to measure the sensitivity and resolution. Selected narrow band NIR LED's were used to illuminate a 6mm diameter circular diffuse plate to create uniform intensity controllable light spot (μW-mW) as target/source for NIR camera's. Layers of (artificial) tissue with controlled thickness could be placed on the spot to mimic a fluorescent `cancer' embedded in tissue. This setup was used to compare a range of NIR sensitive consumer's cameras for potential use in image guided surgery. The image of the spot obtained with the cameras was captured and analyzed using ImageJ software. Enhanced CCD night vision cameras were the most sensitive capable of showing intensities < 1 μW through 5 mm of tissue. However, there was no control over the automatic gain and hence noise level. NIR sensitive DSLR cameras proved relative less sensitive but could be fully manually controlled as to gain (ISO 25600) and exposure time and are therefore preferred for a clinical setting in combination with Wi-Fi remote control. The NIR fluorescence testing setup proved to be useful for camera testing and can be used for development and quality control of new NIR fluorescence guided surgery equipment.

The Art of Astrophotography

NASA Astrophysics Data System (ADS)

Morison, Ian

2017-02-01

1. Imaging star trails; 2. Imaging a constellation with a DSLR and tripod; 3. Imaging the Milky Way with a DSLR and tracking mount; 4. Imaging the Moon with a compact camera or smartphone; 5. Imaging the Moon with a DSLR; 6. Imaging the Pleiades Cluster with a DSLR and small refractor; 7. Imaging the Orion Nebula, M42, with a modified Canon DSLR; 8. Telescopes and their accessories for use in astroimaging; 9. Towards stellar excellence; 10. Cooling a DSLR camera to reduce sensor noise; 11. Imaging the North American and Pelican Nebulae; 12. Combating light pollution - the bane of astrophotographers; 13. Imaging planets with an astronomical video camera or Canon DSLR; 14. Video imaging the Moon with a webcam or DSLR; 15. Imaging the Sun in white light; 16. Imaging the Sun in the light of its H-alpha emission; 17. Imaging meteors; 18. Imaging comets; 19. Using a cooled 'one shot colour' camera; 20. Using a cooled monochrome CCD camera; 21. LRGB colour imaging; 22. Narrow band colour imaging; Appendix A. Telescopes for imaging; Appendix B. Telescope mounts; Appendix C. The effects of the atmosphere; Appendix D. Auto guiding; Appendix E. Image calibration; Appendix F. Practical aspects of astroimaging.

Preliminary calibration results of the wide angle camera of the imaging instrument OSIRIS for the Rosetta mission

NASA Astrophysics Data System (ADS)

Da Deppo, V.; Naletto, G.; Nicolosi, P.; Zambolin, P.; De Cecco, M.; Debei, S.; Parzianello, G.; Ramous, P.; Zaccariotto, M.; Fornasier, S.; Verani, S.; Thomas, N.; Barthol, P.; Hviid, S. F.; Sebastian, I.; Meller, R.; Sierks, H.; Keller, H. U.; Barbieri, C.; Angrilli, F.; Lamy, P.; Rodrigo, R.; Rickman, H.; Wenzel, K. P.

2017-11-01

Rosetta is one of the cornerstone missions of the European Space Agency for having a rendezvous with the comet 67P/Churyumov-Gerasimenko in 2014. The imaging instrument on board the satellite is OSIRIS (Optical, Spectroscopic and Infrared Remote Imaging System), a cooperation among several European institutes, which consists of two cameras: a Narrow (NAC) and a Wide Angle Camera (WAC). The WAC optical design is an innovative one: it adopts an all reflecting, unvignetted and unobstructed two mirror configuration which allows to cover a 12° × 12° field of view with an F/5.6 aperture and gives a nominal contrast ratio of about 10-4. The flight model of this camera has been successfully integrated and tested in our laboratories, and finally has been integrated on the satellite which is now waiting to be launched in February 2004. In this paper we are going to describe the optical characteristics of the camera, and to summarize the results so far obtained with the preliminary calibration data. The analysis of the optical performance of this model shows a good agreement between theoretical performance and experimental results.

Saturn's F-Ring

NASA Technical Reports Server (NTRS)

2000-01-01

This narrow-angle camera image of Saturn's F Ring was taken through the Clear filter while at a distance of 6.9 million km from Saturn on 8 November 1980. The brightness variations of this tightly-constrained ring shown here indicate that the ring is less uniform in makeup than the larger rings. JPL managed the Voyager Project for NASA's Office of Space Science

Vision and spectroscopic sensing for joint tracing in narrow gap laser butt welding

NASA Astrophysics Data System (ADS)

Nilsen, Morgan; Sikström, Fredrik; Christiansson, Anna-Karin; Ancona, Antonio

2017-11-01

The automated laser beam butt welding process is sensitive to positioning the laser beam with respect to the joint because a small offset may result in detrimental lack of sidewall fusion. This problem is even more pronounced in case of narrow gap butt welding, where most of the commercial automatic joint tracing systems fail to detect the exact position and size of the gap. In this work, a dual vision and spectroscopic sensing approach is proposed to trace narrow gap butt joints during laser welding. The system consists of a camera with suitable illumination and matched optical filters and a fast miniature spectrometer. An image processing algorithm of the camera recordings has been developed in order to estimate the laser spot position relative to the joint position. The spectral emissions from the laser induced plasma plume have been acquired by the spectrometer, and based on the measurements of the intensities of selected lines of the spectrum, the electron temperature signal has been calculated and correlated to variations of process conditions. The individual performances of these two systems have been experimentally investigated and evaluated offline by data from several welding experiments, where artificial abrupt as well as gradual deviations of the laser beam out of the joint were produced. Results indicate that a combination of the information provided by the vision and spectroscopic systems is beneficial for development of a hybrid sensing system for joint tracing.

Photoplethysmographic imaging via spectrally demultiplexed erythema fluctuation analysis for remote heart rate monitoring

NASA Astrophysics Data System (ADS)

Deglint, Jason; Chung, Audrey G.; Chwyl, Brendan; Amelard, Robert; Kazemzadeh, Farnoud; Wang, Xiao Yu; Clausi, David A.; Wong, Alexander

2016-03-01

Traditional photoplethysmographic imaging (PPGI) systems use the red, green, and blue (RGB) broadband measurements of a consumer digital camera to remotely estimate a patients heart rate; however, these broadband RGB signals are often corrupted by ambient noise, making the extraction of subtle fluctuations indicative of heart rate difficult. Therefore, the use of narrow-band spectral measurements can significantly improve the accuracy. We propose a novel digital spectral demultiplexing (DSD) method to infer narrow-band spectral information from acquired broadband RGB measurements in order to estimate heart rate via the computation of motion- compensated skin erythema fluctuation. Using high-resolution video recordings of human participants, multiple measurement locations are automatically identified on the cheeks of an individual, and motion-compensated broadband reflectance measurements are acquired at each measurement location over time via measurement location tracking. The motion-compensated broadband reflectance measurements are spectrally demultiplexed using a non-linear inverse model based on the spectral sensitivity of the camera's detector. A PPG signal is then computed from the demultiplexed narrow-band spectral information via skin erythema fluctuation analysis, with improved signal-to-noise ratio allowing for reliable remote heart rate measurements. To assess the effectiveness of the proposed system, a set of experiments involving human motion in a front-facing position were performed under ambient lighting conditions. Experimental results indicate that the proposed system achieves robust and accurate heart rate measurements and can provide additional information about the participant beyond the capabilities of traditional PPGI methods.

Compact Autonomous Hemispheric Vision System

NASA Technical Reports Server (NTRS)

Pingree, Paula J.; Cunningham, Thomas J.; Werne, Thomas A.; Eastwood, Michael L.; Walch, Marc J.; Staehle, Robert L.

2012-01-01

Solar System Exploration camera implementations to date have involved either single cameras with wide field-of-view (FOV) and consequently coarser spatial resolution, cameras on a movable mast, or single cameras necessitating rotation of the host vehicle to afford visibility outside a relatively narrow FOV. These cameras require detailed commanding from the ground or separate onboard computers to operate properly, and are incapable of making decisions based on image content that control pointing and downlink strategy. For color, a filter wheel having selectable positions was often added, which added moving parts, size, mass, power, and reduced reliability. A system was developed based on a general-purpose miniature visible-light camera using advanced CMOS (complementary metal oxide semiconductor) imager technology. The baseline camera has a 92 FOV and six cameras are arranged in an angled-up carousel fashion, with FOV overlaps such that the system has a 360 FOV (azimuth). A seventh camera, also with a FOV of 92 , is installed normal to the plane of the other 6 cameras giving the system a > 90 FOV in elevation and completing the hemispheric vision system. A central unit houses the common electronics box (CEB) controlling the system (power conversion, data processing, memory, and control software). Stereo is achieved by adding a second system on a baseline, and color is achieved by stacking two more systems (for a total of three, each system equipped with its own filter.) Two connectors on the bottom of the CEB provide a connection to a carrier (rover, spacecraft, balloon, etc.) for telemetry, commands, and power. This system has no moving parts. The system's onboard software (SW) supports autonomous operations such as pattern recognition and tracking.

Multispectral Photography

NASA Technical Reports Server (NTRS)

1982-01-01

Model II Multispectral Camera is an advanced aerial camera that provides optimum enhancement of a scene by recording spectral signatures of ground objects only in narrow, preselected bands of the electromagnetic spectrum. Its photos have applications in such areas as agriculture, forestry, water pollution investigations, soil analysis, geologic exploration, water depth studies and camouflage detection. The target scene is simultaneously photographed in four separate spectral bands. Using a multispectral viewer, such as their Model 75 Spectral Data creates a color image from the black and white positives taken by the camera. With this optical image analysis unit, all four bands are superimposed in accurate registration and illuminated with combinations of blue green, red, and white light. Best color combination for displaying the target object is selected and printed. Spectral Data Corporation produces several types of remote sensing equipment and also provides aerial survey, image processing and analysis and number of other remote sensing services.

Feasibility evaluation of a motion detection system with face images for stereotactic radiosurgery.

PubMed

Yamakawa, Takuya; Ogawa, Koichi; Iyatomi, Hitoshi; Kunieda, Etsuo

2011-01-01

In stereotactic radiosurgery we can irradiate a targeted volume precisely with a narrow high-energy x-ray beam, and thus the motion of a targeted area may cause side effects to normal organs. This paper describes our motion detection system with three USB cameras. To reduce the effect of change in illuminance in a tracking area we used an infrared light and USB cameras that were sensitive to the infrared light. The motion detection of a patient was performed by tracking his/her ears and nose with three USB cameras, where pattern matching between a predefined template image for each view and acquired images was done by an exhaustive search method with a general-purpose computing on a graphics processing unit (GPGPU). The results of the experiments showed that the measurement accuracy of our system was less than 0.7 mm, amounting to less than half of that of our previous system.

First Images from NASA's New Moon Mission

NASA Image and Video Library

2009-07-02

These images show cratered regions near the moon's Mare Nubium region, as photographed by the Lunar Reconnaissance Orbiter's LROC instrument. Each image shows a region 1,400 meters (0.87 miles) wide. the bottoms of both images face lunar north. The image below shows the location of these two images in relation to each other. Credit: NASA/Goddard Space Flight Center/Arizona State University

nacl000000fd_boxes_small

NASA Image and Video Library

2009-07-02

These images show cratered regions near the moon's Mare Nubium region, as photographed by the Lunar Reconnaissance Orbiter's LROC instrument. Each image shows a region 1,400 meters (0.87 miles) wide. the bottoms of both images face lunar north. The image below shows the location of these two images in relation to each other. [Locator Image] Credit: NASA/Goddard Space Flight Center/Arizona State University

Improving PET spatial resolution and detectability for prostate cancer imaging

NASA Astrophysics Data System (ADS)

Bal, H.; Guerin, L.; Casey, M. E.; Conti, M.; Eriksson, L.; Michel, C.; Fanti, S.; Pettinato, C.; Adler, S.; Choyke, P.

2014-08-01

Prostate cancer, one of the most common forms of cancer among men, can benefit from recent improvements in positron emission tomography (PET) technology. In particular, better spatial resolution, lower noise and higher detectability of small lesions could be greatly beneficial for early diagnosis and could provide a strong support for guiding biopsy and surgery. In this article, the impact of improved PET instrumentation with superior spatial resolution and high sensitivity are discussed, together with the latest development in PET technology: resolution recovery and time-of-flight reconstruction. Using simulated cancer lesions, inserted in clinical PET images obtained with conventional protocols, we show that visual identification of the lesions and detectability via numerical observers can already be improved using state of the art PET reconstruction methods. This was achieved using both resolution recovery and time-of-flight reconstruction, and a high resolution image with 2 mm pixel size. Channelized Hotelling numerical observers showed an increase in the area under the LROC curve from 0.52 to 0.58. In addition, a relationship between the simulated input activity and the area under the LROC curve showed that the minimum detectable activity was reduced by more than 23%.

Remote gaze tracking system on a large display.

PubMed

Lee, Hyeon Chang; Lee, Won Oh; Cho, Chul Woo; Gwon, Su Yeong; Park, Kang Ryoung; Lee, Heekyung; Cha, Jihun

2013-10-07

We propose a new remote gaze tracking system as an intelligent TV interface. Our research is novel in the following three ways: first, because a user can sit at various positions in front of a large display, the capture volume of the gaze tracking system should be greater, so the proposed system includes two cameras which can be moved simultaneously by panning and tilting mechanisms, a wide view camera (WVC) for detecting eye position and an auto-focusing narrow view camera (NVC) for capturing enlarged eye images. Second, in order to remove the complicated calibration between the WVC and NVC and to enhance the capture speed of the NVC, these two cameras are combined in a parallel structure. Third, the auto-focusing of the NVC is achieved on the basis of both the user's facial width in the WVC image and a focus score calculated on the eye image of the NVC. Experimental results showed that the proposed system can be operated with a gaze tracking accuracy of ±0.737°~±0.775° and a speed of 5~10 frames/s.

Remote Gaze Tracking System on a Large Display

PubMed Central

Lee, Hyeon Chang; Lee, Won Oh; Cho, Chul Woo; Gwon, Su Yeong; Park, Kang Ryoung; Lee, Heekyung; Cha, Jihun

2013-01-01

We propose a new remote gaze tracking system as an intelligent TV interface. Our research is novel in the following three ways: first, because a user can sit at various positions in front of a large display, the capture volume of the gaze tracking system should be greater, so the proposed system includes two cameras which can be moved simultaneously by panning and tilting mechanisms, a wide view camera (WVC) for detecting eye position and an auto-focusing narrow view camera (NVC) for capturing enlarged eye images. Second, in order to remove the complicated calibration between the WVC and NVC and to enhance the capture speed of the NVC, these two cameras are combined in a parallel structure. Third, the auto-focusing of the NVC is achieved on the basis of both the user's facial width in the WVC image and a focus score calculated on the eye image of the NVC. Experimental results showed that the proposed system can be operated with a gaze tracking accuracy of ±0.737°∼±0.775° and a speed of 5∼10 frames/s. PMID:24105351

Fundamentals of in Situ Digital Camera Methodology for Water Quality Monitoring of Coast and Ocean

PubMed Central

Goddijn-Murphy, Lonneke; Dailloux, Damien; White, Martin; Bowers, Dave

2009-01-01

Conventional digital cameras, the Nikon Coolpix885® and the SeaLife ECOshot®, were used as in situ optical instruments for water quality monitoring. Measured response spectra showed that these digital cameras are basically three-band radiometers. The response values in the red, green and blue bands, quantified by RGB values of digital images of the water surface, were comparable to measurements of irradiance levels at red, green and cyan/blue wavelengths of water leaving light. Different systems were deployed to capture upwelling light from below the surface, while eliminating direct surface reflection. Relationships between RGB ratios of water surface images, and water quality parameters were found to be consistent with previous measurements using more traditional narrow-band radiometers. This current paper focuses on the method that was used to acquire digital images, derive RGB values and relate measurements to water quality parameters. Field measurements were obtained in Galway Bay, Ireland, and in the Southern Rockall Trough in the North Atlantic, where both yellow substance and chlorophyll concentrations were successfully assessed using the digital camera method. PMID:22346729

Wide-Field Optic for Autonomous Acquisition of Laser Link

NASA Technical Reports Server (NTRS)

Page, Norman A.; Charles, Jeffrey R.; Biswas, Abhijit

2011-01-01

An innovation reported in Two-Camera Acquisition and Tracking of a Flying Target, NASA Tech Briefs, Vol. 32, No. 8 (August 2008), p. 20, used a commercial fish-eye lens and an electronic imaging camera for initially locating objects with subsequent handover to an actuated narrow-field camera. But this operated against a dark-sky background. An improved solution involves an optical design based on custom optical components for the wide-field optical system that directly addresses the key limitations in acquiring a laser signal from a moving source such as an aircraft or a spacecraft. The first challenge was to increase the light collection entrance aperture diameter, which was approximately 1 mm in the first prototype. The new design presented here increases this entrance aperture diameter to 4.2 mm, which is equivalent to a more than 16 times larger collection area. One of the trades made in realizing this improvement was to restrict the field-of-view to +80 deg. elevation and 360 azimuth. This trade stems from practical considerations where laser beam propagation over the excessively high air mass, which is in the line of sight (LOS) at low elevation angles, results in vulnerability to severe atmospheric turbulence and attenuation. An additional benefit of the new design is that the large entrance aperture is maintained even at large off-axis angles when the optic is pointed at zenith. The second critical limitation for implementing spectral filtering in the design was tackled by collimating the light prior to focusing it onto the focal plane. This allows the placement of the narrow spectral filter in the collimated portion of the beam. For the narrow band spectral filter to function properly, it is necessary to adequately control the range of incident angles at which received light intercepts the filter. When this angle is restricted via collimation, narrower spectral filtering can be implemented. The collimated beam (and the filter) must be relatively large to reduce the incident angle down to only a few degrees. In the presented embodiment, the filter diameter is more than ten times larger than the entrance aperture. Specifically, the filter has a clear aperture of about 51 mm. The optical design is refractive, and is comprised of nine custom refractive elements and an interference filter. The restricted maximum angle through the narrow-band filter ensures the efficient use of a 2-nm noise equivalent bandwidth spectral width optical filter at low elevation angles (where the range is longest), at the expense of less efficiency for high elevations, which can be tolerated because the range at high elevation angles is shorter. The image circle is 12 mm in diameter, mapped to 80 x 360 of sky, centered on the zenith.

First NAC Image Obtained in Mercury Orbit

NASA Image and Video Library

2017-12-08

NASA image acquired: March 29, 2011 This is the first image of Mercury taken from orbit with MESSENGER’s Narrow Angle Camera (NAC). MESSENGER’s camera system, the Mercury Dual Imaging System (MDIS), has two cameras: the Narrow Angle Camera and the Wide Angle Camera (WAC). Comparison of this image with MESSENGER’s first WAC image of the same region shows the substantial difference between the fields of view of the two cameras. At 1.5°, the field of view of the NAC is seven times smaller than the 10.5° field of view of the WAC. This image was taken using MDIS’s pivot. MDIS is mounted on a pivoting platform and is the only instrument in MESSENGER’s payload capable of movement independent of the spacecraft. The other instruments are fixed in place, and most point down the spacecraft’s boresight at all times, relying solely on the guidance and control system for pointing. The 90° range of motion of the pivot gives MDIS a much-needed extra degree of freedom, allowing MDIS to image the planet’s surface at times when spacecraft geometry would normally prevent it from doing so. The pivot also gives MDIS additional imaging opportunities by allowing it to view more of the surface than that at which the boresight-aligned instruments are pointed at any given time. On March 17, 2011 (March 18, 2011, UTC), MESSENGER became the first spacecraft ever to orbit the planet Mercury. The mission is currently in the commissioning phase, during which spacecraft and instrument performance are verified through a series of specially designed checkout activities. In the course of the one-year primary mission, the spacecraft's seven scientific instruments and radio science investigation will unravel the history and evolution of the Solar System's innermost planet. Visit the Why Mercury? section of this website to learn more about the science questions that the MESSENGER mission has set out to answer. Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Join us on Facebook

Experimental study of 3-D structure and evolution of foam

NASA Astrophysics Data System (ADS)

Thoroddsen, S. T.; Tan, E.; Bauer, J. M.

1998-11-01

Liquid foam coarsens due to diffusion of gas between adjacent foam cells. This evolution process is slow, but leads to rapid topological changes taking place during localized rearrangements of Plateau borders or disappearance of small cells. We are developing a new imaging technique to construct the three-dimensional topology of real soap foam contained in a small glass container. The technique uses 3 video cameras equipped with lenses having narrow depth-of-field. These cameras are moved with respect to the container, in effect obtaining numerous slices through the foam. Preliminary experimental results showing typical rearrangement events will also be presented. These events involve for example disappearance of either triangular or rectangular cell faces.

Surface compositional variation on the comet 67P/Churyumov-Gerasimenko by OSIRIS data

NASA Astrophysics Data System (ADS)

Barucci, M. A.; Fornasier, S.; Feller, C.; Perna, D.; Hasselmann, H.; Deshapriya, J. D. P.; Fulchignoni, M.; Besse, S.; Sierks, H.; Forgia, F.; Lazzarin, M.; Pommerol, A.; Oklay, N.; Lara, L.; Scholten, F.; Preusker, F.; Leyrat, C.; Pajola, M.; Osiris-Rosetta Team

2015-10-01

Since the Rosetta mission arrived at the comet 67P/Churyumov-Gerasimenko (67/P C-G) on July 2014, the comet nucleus has been mapped by both OSIRIS (Optical, Spectroscopic, and Infrared Remote Imaging System, [1]) NAC (Narrow Angle Camera) and WAC (Wide Angle Camera) acquiring a huge quantity of surface's images at different wavelength bands, under variable illumination conditions and spatial resolution, and producing the most detailed maps at the highest spatial resolution of a comet nucleus surface.67/P C-G's nucleus shows an irregular bi-lobed shape of complex morphology with terrains showing intricate features [2, 3] and a heterogeneity surface at different scales.

PIA01492

NASA Image and Video Library

1998-10-30

This picture of Neptune was produced from the last whole planet images taken through the green and orange filters on NASA's Voyager 2 narrow angle camera. The images were taken at a range of 4.4 million miles from the planet, 4 days and 20 hours before closest approach. The picture shows the Great Dark Spot and its companion bright smudge; on the west limb the fast moving bright feature called Scooter and the little dark spot are visible. These clouds were seen to persist for as long as Voyager's cameras could resolve them. North of these, a bright cloud band similar to the south polar streak may be seen. http://photojournal.jpl.nasa.gov/catalog/PIA01492

Modelling of the outburst on July 29th , 2015 observed with OSIRIS in the southern hemisphere of comet 67P/Churyumov-Gerasimenko

NASA Astrophysics Data System (ADS)

Gicquel, Adeline; Vincent, Jean-Baptiste; Sierks, Holger; Rose, Martin; Agarwal, Jessica; Deller, Jakob; Guettler, Carsten; Hoefner, Sebastian; Hofmann, Marc; Hu, Xuanyu; Kovacs, Gabor; Oklay Vincent, Nilda; Shi, Xian; Tubiana, Cecilia; Barbieri, Cesare; Lamy, Phylippe; Rodrigo, Rafael; Koschny, Detlef; Rickman, Hans; OSIRIS Team

2016-10-01

Images of the nucleus and the coma (gas and dust) of comet 67P/Churyumov- Gerasimenko have been acquired by the OSIRIS (Optical, Spectroscopic, and Infrared Remote Imaging System) cameras system since March 2014 using both the wide angle camera (WAC) and the narrow angle camera (NAC). We are using the NAC camera to study the bright outburst observed on July 29th, 2015 in the southern hemisphere. The NAC camera's wavelength ranges between 250-1000 nm with a combination of 12 filters. The high spatial resolution is needed to localize the source point of the outburst on the surface of the nucleus. At the time of the observations, the heliocentric distance was 1.25AU and the distance between the spacecraft and the comet was 126 km. We aim to understand the physics leading to such outgassing: Is the jet associated to the outbursts controlled by the micro-topography? Or by ice suddenly exposed? We are using the Direct Simulation Monte Carlo (DSMC) method to study the gas flow close to the nucleus. The goal of the DSMC code is to reproduce the opening angle of the jet, and constrain the outgassing ratio between outburst source and local region. The results of this model will be compared to the images obtained with the NAC camera.

High-resolution topomapping of candidate MER landing sites with Mars Orbiter Camera narrow-angle images

USGS Publications Warehouse

Kirk, R.L.; Howington-Kraus, E.; Redding, B.; Galuszka, D.; Hare, T.M.; Archinal, B.A.; Soderblom, L.A.; Barrett, J.M.

2003-01-01

We analyzed narrow-angle Mars Orbiter Camera (MOC-NA) images to produce high-resolution digital elevation models (DEMs) in order to provide topographic and slope information needed to assess the safety of candidate landing sites for the Mars Exploration Rovers (MER) and to assess the accuracy of our results by a variety of tests. The mapping techniques developed also support geoscientific studies and can be used with all present and planned Mars-orbiting scanner cameras. Photogrammetric analysis of MOC stereopairs yields DEMs with 3-pixel (typically 10 m) horizontal resolution, vertical precision consistent with ???0.22 pixel matching errors (typically a few meters), and slope errors of 1-3??. These DEMs are controlled to the Mars Orbiter Laser Altimeter (MOLA) global data set and consistent with it at the limits of resolution. Photoclinometry yields DEMs with single-pixel (typically ???3 m) horizontal resolution and submeter vertical precision. Where the surface albedo is uniform, the dominant error is 10-20% relative uncertainty in the amplitude of topography and slopes after "calibrating" photoclinometry against a stereo DEM to account for the influence of atmospheric haze. We mapped portions of seven candidate MER sites and the Mars Pathfinder site. Safety of the final four sites (Elysium, Gusev, Isidis, and Meridiani) was assessed by mission engineers by simulating landings on our DEMs of "hazard units" mapped in the sites, with results weighted by the probability of landing on those units; summary slope statistics show that most hazard units are smooth, with only small areas of etched terrain in Gusev crater posing a slope hazard.

Solar System Portrait - Views of 6 Planets

NASA Image and Video Library

1996-09-13

These six narrow-angle color images were made from the first ever portrait of the solar system taken by NASA’s Voyager 1, which was more than 4 billion miles from Earth and about 32 degrees above the ecliptic. The spacecraft acquired a total of 60 frames for a mosaic of the solar system which shows six of the planets. Mercury is too close to the sun to be seen. Mars was not detectable by the Voyager cameras due to scattered sunlight in the optics, and Pluto was not included in the mosaic because of its small size and distance from the sun. These blown-up images, left to right and top to bottom are Venus, Earth, Jupiter, and Saturn, Uranus, Neptune. The background features in the images are artifacts resulting from the magnification. The images were taken through three color filters -- violet, blue and green -- and recombined to produce the color images. Jupiter and Saturn were resolved by the camera but Uranus and Neptune appear larger than they really are because of image smear due to spacecraft motion during the long (15 second) exposure times. Earth appears to be in a band of light because it coincidentally lies right in the center of the scattered light rays resulting from taking the image so close to the sun. Earth was a crescent only 0.12 pixels in size. Venus was 0.11 pixel in diameter. The planetary images were taken with the narrow-angle camera (1500 mm focal length). http://photojournal.jpl.nasa.gov/catalog/PIA00453

Spectral methods to detect cometary minerals with OSIRIS on board Rosetta

NASA Astrophysics Data System (ADS)

Oklay, N.; Vincent, J.-B.; Sierks, H.

2013-09-01

Comet 67P/Churyumov-Gerasimenko is going to be observed by the OSIRIS scientific imager (Keller et al. 2007) on board ESA's spacecraft Rosetta in the wavelength range of 250-1000 nm with a combination of 12 filters for the narrow angle camera (NAC) and 14 combination of 12 filters for the narrow angle camera (NAC) and 14 filters in the wavelength range of 240-720 nm for the wide angle camera (WAC). NAC filters are suitable to surface composition studies, while WAC filters are designed for gas and radical emission studies. In order to investigate the composition of the comet surface from the observed images, we need to understand how to detect different minerals and which compositional information can be derived from the NAC filters. Therefore, the most common cometary silicates e.g. enstatite, forsterite are investigated with two hydrated silicates (serpentine and smectite) for the determina- tion of the spectral methods. Laboratory data of those selected minerals are collected from RELAB database (http://www.planetary.brown.edu/relabdocs/relab.htm) and absolute spectra of the minerals observed by OSIRIS NAC filters are calculated. Due to the limited spectral range of the laboratory data, Far-UV and Neutral density filters of NAC are excluded from this analysis. Considered NAC filters in this study are represented in Table 1 and the number of collected laboratory data are presented in Table 2. Detection and separation of the minerals will not only allow us to study the surface composition but also to study observed composition changes due to the cometary activity during the mission.

Schiaparelli Crater Rim and Interior Deposits

NASA Technical Reports Server (NTRS)

1998-01-01

A portion of the rim and interior of the large impact crater Schiaparelli is seen at different resolutions in images acquired October 18, 1997 by the Mars Global Surveyor Orbiter Camera (MOC) and by the Viking Orbiter 1 twenty years earlier. The left image is a MOC wide angle camera 'context' image showing much of the eastern portion of the crater at roughly 1 km (0.6 mi) per picture element. The image is about 390 by 730 km (240 X 450 miles). Shown within the wide angle image is the outline of a portion of the best Viking image (center, 371S53), acquired at a resolution of about 240 m/pixel (790 feet). The area covered is 144 X 144 km (89 X 89 miles). The right image is the high resolution narrow angle camera view. The area covered is very small--3.9 X 10.2 km (2.4 X 6.33 mi)--but is seen at 63 times higher resolution than the Viking image. The subdued relief and bright surface are attributed to blanketing by dust; many small craters have been completely filled in, and only the most recent (and very small) craters appear sharp and bowl-shaped. Some of the small craters are only 10-12 m (30-35 feet) across. Occasional dark streaks on steeper slopes are small debris slides that have probably occurred in the past few decades. The two prominent, narrow ridges in the center of the image may be related to the adjustment of the crater floor to age or the weight of the material filling the basin.

Malin Space Science Systems (MSSS) and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO.

Geological features and evolution history of Sinus Iridum, the Moon

NASA Astrophysics Data System (ADS)

Qiao, Le; Xiao, Long; Zhao, Jiannan; Huang, Qian; Haruyama, Junichi

2014-10-01

The Sinus Iridum region is one of the important candidate landing areas for the future Chinese lunar robotic and human missions. Considering its flat topography, abundant geomorphic features and complex evolutionary history, this region shows great significance to both lunar science and landing exploration, including powered descent, surface trafficability and in-situ exploration. First, we use Lunar Reconnaissance Orbiter (LRO) Altimeter (LOLA) and Camera (LROC) data to characterize regional topographic and geomorphological features within Sinus Iridum, e.g., wrinkle ridges and sinuous rilles. Then, we deduce the iron and titanium content for the mare surface using the Clementine ultraviolet-visible (UVVIS) data and generate mineral absorption features using the Chandrayaan-1 Moon Mineralogy Mapper (M3) spectrometer data. Later, we date the mare surface using crater size-frequency distribution (CSFD) method. CSFD measurements show that this region has experienced four major lava infilling events with model ages ranging from 3.32 Ga to 2.50 Ga. The regional magmatic activities evolved from Imbrian-aged low-titanium to Eratosthenian-aged medium-titanium. The inner Sinus Iridum is mainly composed of pyroxene-rich basalts with olivine abundance increasing with time, while the surrounding highlands have a feldspar-dominated composition. In the northern wall of Sinus Iridum, some potential olivine-rich materials directly excavated from the lunar mantle are visible. The Sinus Iridum region is an ideal target for future landing exploration, we propose two candidate landing sites for the future Chinese robotic and human missions.

Mars Image Collection Mosaic Builder

NASA Technical Reports Server (NTRS)

Plesea, Lucian; Hare, Trent

2008-01-01

A computer program assembles images from the Mars Global Surveyor (MGS) Mars Observer Camera Narrow Angle (MOCNA) collection to generate a uniform-high-resolution, georeferenced, uncontrolled mosaic image of the Martian surface. At the time of reporting the information for this article, the mosaic covered 7 percent of the Martian surface and contained data from more than 50,000 source images acquired under various light conditions at various resolutions.

Filtered Rayleigh Scattering Measurements in a Buoyant Flow Field

DTIC Science & Technology

2008-03-01

ENY/08-M22 Abstract Filtered Rayleigh Scattering (FRS) is a non-intrusive, laser -based flow characterization technique that consists of a narrow...linewidth laser , a molecular absorption filter, and a high resolution camera behind the filter to record images. Gases of different species have...different molecular scattering cross-sections that become apparent as they pass through the interrogating laser light source, and this difference is

1997 Leonid Shower From Space

NASA Technical Reports Server (NTRS)

Jenniskens, Peter; Nugent, David; Murthy, Jayant; Tedesco, Ed; DeVincenzi, Donal L. (Technical Monitor)

2000-01-01

In November 1997, the Midcourse Space Experiment satellite (MSX) was deployed to observe the Leonid shower from space. The shower lived up to expectations, with abundant bright fireballs. Twenty-nine meteors were detected by a wide-angle, visible wavelength, camera near the limb of the Earth in a 48-minute interval, and three meteors by the narrow field camera. This amounts to a meteoroid influx of 5.5 +/- 0.6 10(exp -5)/sq km hr for masses greater than 0.3 gram. The limiting magnitude for limb observations of Leonid meteors was measured at M(sub v) = -1.5 magn The Leonid shower magnitude population index was 1.6 +/- 0.2 down to M(sub v) = -7 magn., with no sign of an upper mass cut-off.

Rosetta/OSIRIS - Nucleus morphology and activity of comet 67P/Churyumov-Gerasimenko

NASA Astrophysics Data System (ADS)

Sierks, Holger; Barbieri, Cesare; Lamy, Philippe; Rickman, Hans; Rodrigo, Rafael; Koschny, Detlef

2015-04-01

ESA's Rosetta mission arrived on August 6, 2014, at target comet 67P/Churyumov-Gerasimenko after 10 years of cruise. OSIRIS (Optical, Spectroscopic, and Infrared Remote Imaging System) is the scientific imaging system onboard Rosetta. It comprises a Narrow Angle Camera (NAC) for nucleus surface and dust studies and a Wide Angle Camera (WAC) for the wide field coma investigations. OSIRIS imaged the nucleus and coma of the comet from the arrival throughout the mapping phase, PHILAE landing, early escort phase and close fly-by. The overview paper will discuss the surface morpholo-gy and activity of the nucleus as seen in gas, dust, and local jets as well as small scale structures in the local topography.

Mimas Looks On

NASA Image and Video Library

2004-09-07

Lonely Mimas swings around Saturn, seeming to gaze down at the planet's splendid rings. The outermost, narrow F ring is visible here and exhibits some clumpy structure near the bottom of the frame. The shadow of Saturn's southern hemisphere stretches almost entirely across the rings. Mimas is 398 kilometers (247 miles) wide. The image was taken with the Cassini spacecraft narrow angle camera on August 15, 2004, at a distance of 8.8 million kilometers (5.5 million miles) from Saturn, through a filter sensitive to visible red light. The image scale is 53 kilometers (33 miles) per pixel. Contrast was slightly enhanced to aid visibility.almost entirely across the rings. Mimas is 398 kilometers (247 miles) wide. http://photojournal.jpl.nasa.gov/catalog/PIA06471

Instrumentation for remote sensing solar radiation from light aircraft.

PubMed

Howard, J A; Barton, I J

1973-10-01

The paper outlines the instrumentation needed to study, from a light aircraft, the solar radiation reflected by ground surfaces and the incoming solar radiation. A global shortwave radiometer was mounted on the roof of the aircraft and a specially designed mount was used to support a downward pointing 70-mm aerial camera, a downward pointing narrow-beam pyranometer, and, sometimes, a downward pointing global shortwave pyranometer. Calibration factors were determined for the three pyranometers by comparison with a standard Angstrom compensation pyrheliometer. Results have indicated trends in the albedos of major plant communities and have shown that the calculated albedo values vary according to whether the downward pointing instrument is narrow-beam or global. Comparisons were also made with albedos measured on the ground.

Feasibility Study of Utilization of Action Camera, GoPro Hero 4, Google Glass, and Panasonic HX-A100 in Spine Surgery.

PubMed

Lee, Chang Kyu; Kim, Youngjun; Lee, Nam; Kim, Byeongwoo; Kim, Doyoung; Yi, Seong

2017-02-15

Study for feasibility of commercially available action cameras in recording video of spine. Recent innovation of the wearable action camera with high-definition video recording enables surgeons to use camera in the operation at ease without high costs. The purpose of this study is to compare the feasibility, safety, and efficacy of commercially available action cameras in recording video of spine surgery. There are early reports of medical professionals using Google Glass throughout the hospital, Panasonic HX-A100 action camera, and GoPro. This study is the first report for spine surgery. Three commercially available cameras were tested: GoPro Hero 4 Silver, Google Glass, and Panasonic HX-A100 action camera. Typical spine surgery was selected for video recording; posterior lumbar laminectomy and fusion. Three cameras were used by one surgeon and video was recorded throughout the operation. The comparison was made on the perspective of human factor, specification, and video quality. The most convenient and lightweight device for wearing and holding throughout the long operation time was Google Glass. The image quality; all devices except Google Glass supported HD format and GoPro has unique 2.7K or 4K resolution. Quality of video resolution was best in GoPro. Field of view, GoPro can adjust point of interest, field of view according to the surgery. Narrow FOV option was the best for recording in GoPro to share the video clip. Google Glass has potentials by using application programs. Connectivity such as Wi-Fi and Bluetooth enables video streaming for audience, but only Google Glass has two-way communication feature in device. Action cameras have the potential to improve patient safety, operator comfort, and procedure efficiency in the field of spinal surgery and broadcasting a surgery with development of the device and applied program in the future. N/A.

TIFR Near Infrared Imaging Camera-II on the 3.6 m Devasthal Optical Telescope

NASA Astrophysics Data System (ADS)

Baug, T.; Ojha, D. K.; Ghosh, S. K.; Sharma, S.; Pandey, A. K.; Kumar, Brijesh; Ghosh, Arpan; Ninan, J. P.; Naik, M. B.; D’Costa, S. L. A.; Poojary, S. S.; Sandimani, P. R.; Shah, H.; Krishna Reddy, B.; Pandey, S. B.; Chand, H.

Tata Institute of Fundamental Research (TIFR) Near Infrared Imaging Camera-II (TIRCAM2) is a closed-cycle Helium cryo-cooled imaging camera equipped with a Raytheon 512×512 pixels InSb Aladdin III Quadrant focal plane array (FPA) having sensitivity to photons in the 1-5μm wavelength band. In this paper, we present the performance of the camera on the newly installed 3.6m Devasthal Optical Telescope (DOT) based on the calibration observations carried out during 2017 May 11-14 and 2017 October 7-31. After the preliminary characterization, the camera has been released to the Indian and Belgian astronomical community for science observations since 2017 May. The camera offers a field-of-view (FoV) of ˜86.5‧‧×86.5‧‧ on the DOT with a pixel scale of 0.169‧‧. The seeing at the telescope site in the near-infrared (NIR) bands is typically sub-arcsecond with the best seeing of ˜0.45‧‧ realized in the NIR K-band on 2017 October 16. The camera is found to be capable of deep observations in the J, H and K bands comparable to other 4m class telescopes available world-wide. Another highlight of this camera is the observational capability for sources up to Wide-field Infrared Survey Explorer (WISE) W1-band (3.4μm) magnitudes of 9.2 in the narrow L-band (nbL; λcen˜ 3.59μm). Hence, the camera could be a good complementary instrument to observe the bright nbL-band sources that are saturated in the Spitzer-Infrared Array Camera (IRAC) ([3.6] ≲ 7.92 mag) and the WISE W1-band ([3.4] ≲ 8.1 mag). Sources with strong polycyclic aromatic hydrocarbon (PAH) emission at 3.3μm are also detected. Details of the observations and estimated parameters are presented in this paper.

First Results from the Wide Angle Camera of the ROSETTA Mission .

NASA Astrophysics Data System (ADS)

Barbieri, C.; Fornasier, S.; Bertini, I.; Angrilli, F.; Bianchini, G. A.; Debei, S.; De Cecco, M.; Parzianello, G.; Zaccariotto, M.; Da Deppo, V.; Naletto, G.

This paper gives a brief description of the Wide Angle Camera (WAC), built by the Center of Studies and Activities for Space (CISAS) of the University of Padova for the ESA ROSETTA Mission, of data we have obtained about the new mission targets, and of the first results achieved after the launch in March 2004. The WAC is part of the OSIRIS imaging system, built under the PI-ship of Dr. U. Keller (Max-Planck-Institute for Solar System Studies) which comprises also a Narrow Angle Camera (NAC) built by the Laboratoire d'Astrophysique Spatiale (LAS) of Marseille. CISAS had also the responsibility to build the shutter and the front door mechanism for the NAC. The images show the excellent optical quality of the WAC, exceeding the specifications both in term of encircled energy (80% in one pixel over a FoV of 12×12 sq degree), limiting magnitude (fainter than the 13th in 30s exposure time through a wideband red filter) and amount of distortions.

High Resolution Seamless Dom Generation Over CHANG'E-5 Landing Area Using Lroc Nac Images

NASA Astrophysics Data System (ADS)

Di, K.; Jia, M.; Xin, X.; Liu, B.; Liu, Z.; Peng, M.; Yue, Z.

2018-04-01

Chang'e-5, China's first sample return lunar mission, will be launched in 2019, and the planned landing area is near Mons Rümker in Oceanus Procellarum. High-resolution and high-precision mapping of the landing area is of great importance for supporting scientific analysis and safe landing. This paper proposes a systematic method for large area seamless digital orthophoto map (DOM) generation, and presents the mapping result of Chang'e-5 landing area using over 700 LROC NAC images. The developed method mainly consists of two stages of data processing: stage 1 includes subarea block adjustment with rational function model (RFM) and seamless subarea DOM generation; stage 2 includes whole area adjustment through registration of the subarea DOMs with thin plate spline model and seamless DOM mosaicking. The resultant seamless DOM coves a large area (20° longitude × 4° latitude) and is tied to the widely used reference DEM - SLDEM2015. As a result, the RMS errors of the tie points are all around half pixel in image space, indicating a high internal precision; the RMS errors of the control points are about one grid cell size of SLDEM2015, indicating that the resultant DOM is tied to SLDEM2015 well.

Neptune - full ring system

NASA Technical Reports Server (NTRS)

1989-01-01

This pair of Voyager 2 images (FDS 11446.21 and 11448.10), two 591-s exposures obtained through the clear filter of the wide angle camera, show the full ring system with the highest sensitivity. Visible in this figure are the bright, narrow N53 and N63 rings, the diffuse N42 ring, and (faintly) the plateau outside of the N53 ring (with its slight brightening near 57,500 km).

Note: Retrofitting an analog spectrometer for high resolving power in NUV-NIR

NASA Astrophysics Data System (ADS)

Taylor, Andrew S.; Batishchev, Oleg V.

2017-11-01

We demonstrate how an older spectrometer designed for photographic films can be efficiently retrofitted with a narrow laser-cut slit and a modern μm-pixel-size imaging CMOS camera, yielding sub-pm resolution in the broad near ultraviolet to near infrared (NUV-NIR) spectral range. Resolving power approaching 106 is achieved. Such digital retrofitting of an analog instrument is practical for research and teaching laboratories.

Efficient Feature Extraction and Likelihood Fusion for Vehicle Tracking in Low Frame Rate Airborne Video

DTIC Science & Technology

2010-07-01

imagery, persistent sensor array I. Introduction New device fabrication technologies and heterogeneous embedded processors have led to the emergence of a...geometric occlusions between target and sensor , motion blur, urban scene complexity, and high data volumes. In practical terms the targets are small...distributed airborne narrow-field-of-view video sensor networks. Airborne camera arrays combined with com- putational photography techniques enable the

Up Close to Mimas

NASA Technical Reports Server (NTRS)

2005-01-01

During its approach to Mimas on Aug. 2, 2005, the Cassini spacecraft narrow-angle camera obtained multi-spectral views of the moon from a range of 228,000 kilometers (142,500 miles).

This image is a narrow angle clear-filter image which was processed to enhance the contrast in brightness and sharpness of visible features.

Herschel crater, a 140-kilometer-wide (88-mile) impact feature with a prominent central peak, is visible in the upper right of this image.

This image was obtained when the Cassini spacecraft was above 25 degrees south, 134 degrees west latitude and longitude. The Sun-Mimas-spacecraft angle was 45 degrees and north is at the top.

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging operations center is based at the Space Science Institute in Boulder, Colo.

For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov . The Cassini imaging team homepage is at http://ciclops.org .

Effects of Rocket Exhaust on Lunar Soil Reflectance Properties

NASA Astrophysics Data System (ADS)

Clegg, R. N.; Jolliff, B. L.; Robinson, M. S.; Hapke, B. W.; Plescia, J. B.

2012-12-01

The Apollo, Surveyor, and Luna spacecraft descent engine plumes affected the regolith at and surrounding their landing sites. Owing to the lack of rapid weathering processes on the Moon, surface alterations are still visible as photometric anomalies in Lunar Reconnaissance Orbiter Camera (LROC) Narrow Angle Camera (NAC) images. These areas are interpreted as disturbance of the regolith by rocket exhaust during descent of the spacecraft, which we refer to as "blast zones" (BZs). The BZs consist of an area of lower reflectance (LR-BZ) compared to the surroundings that extends up to a few meters out from the landers, as well as a broader halo of higher reflectance (HR-BZ) that extends tens to hundreds of meters out from the landers. We use phase-ratio images for each landing site to determine the spatial extent of the disturbed regions and to quantify differences in reflectance and backscattering characteristics within the BZs compared to nearby undisturbed regolith. We also compare the reflectance changes and BZ dimensions at the Apollo sites with those at Luna and Surveyor sites. We seek to determine the effects of rocket exhaust in terms of erosion and particle redistribution, as well as the cause(s) of the reflectance variations, i.e., physical changes at the regolith surface. When approximated as an ellipse, the average Apollo BZ area is ~29,000 m2 (~175 ± 60 m by 200 ± 27 m) which is 10x larger than the average Luna BZ, and over 100x larger than the average Surveyor BZ. Moreover, BZ area scales roughly with lander mass (as a proxy for thrust). The LR-BZs are evident at the Apollo sites, especially where astronaut bioturbation has roughened the soil, leading to a 2-14% reduction in reflectance at ~30° phase. The LR-BZs at the Luna and Surveyor sites are less evident and may be mostly confined to the area below the landers. The average normalized reflectance in the HR-BZs for images with a 30° phase angle is 2-16% higher than in the undisturbed surrounding areas; this magnitude is the same, within uncertainty, for all sites, indicating a common process or combination of processes causing differences in reflectance properties of the regolith. Phase-ratio images and photometric data collected over a range of illumination geometries show that a greater separation in reflectance occurs between the HR-BZs and undisturbed areas with increasing phase angle and indicate that the HR-BZs are less backscattering than undisturbed areas. As working hypotheses, we consider the following possibilities to explain BZ reflectance phenomena: change in macroscopic roughness, microscopic modification of surface structure, redistribution of fines (excavation from LR-BZ and deposition in HR-BZ), change in compaction, contamination from fuel, and modification of maturity. The LR-BZ is affected by macroscopic disruption of the surface and increased shadowing. We infer that HR-BZ reflectance has been affected by scouring from particles entrained by exhaust gases with low-angle trajectories. Entrained particles with trajectories greater than a few degrees relative to horizontal travel well beyond the BZ boundary and do not contribute to BZ reflectance variations. Regolith particle interactions with surface soil within HR-BZs may destroy fine-scale surface structure (e.g., "fairy-castle") and decrease macroscopic roughness, contributing to a decrease in backscattering character within the HR-BZ.

A General Closed-Form Solution for the Lunar Reconnaissance Orbiter (LRO) Antenna Pointing System

NASA Technical Reports Server (NTRS)

Shah, Neerav; Chen, J. Roger; Hashmall, Joseph A.

2010-01-01

The National Aeronautics and Space Administration s (NASA) Lunar Reconnaissance Orbiter (LRO) launched on June 18, 2009 from the Cape Canaveral Air Force Station aboard an Atlas V launch vehicle into a direct insertion trajectory to the Moon LRO, designed, built, and operated by the NASA Goddard Space Flight Center in Greenbelt, MD, is gathering crucial data on the lunar environment that will help astronauts prepare for long-duration lunar expeditions. During the mission s nominal life of one year its six instruments and one technology demonstrator will find safe landing site, locate potential resources, characterize the radiation environment and test new technology. To date, LRO has been operating well within the bounds of its requirements and has been collecting excellent science data images taken from the LRO Camera Narrow Angle Camera (LROC NAC) of the Apollo landing sites have appeared on cable news networks. A significant amount of information on LRO s science instruments is provided at the LRO mission webpage. LRO s Attitude Control System (ACS), in addition to controlling the orientation of the spacecraft is also responsible for pointing the High Gain Antenna (HGA). A dual-axis (or double-gimbaled) antenna, deployed on a meter-long boom, is required to point at a selected Earth ground station. Due to signal loss over the distance from the Moon to Earth, pointing precision for the antenna system is very tight. Since the HGA has to be deployed in spaceflight, its exact geometry relative to the spacecraft body is uncertain. In addition, thermal distortions and mechanical errors/tolerances must be characterized and removed to realize the greatest gain from the antenna system. These reasons necessitate the need for an in-flight calibration. Once in orbit around the moon, a series of attitude maneuvers was conducted to provide data needed to determine optimal parameters to load onboard, which would account for the environmental and mechanical errors at any antenna orientation. The nominal geometry for the HGA involves an outer gimbal axis that is exactly perpendicular to the inner gimbal axis, and a target direction that is exactly perpendicular to the outer gimbal axis. For this nominal geometry, closed-form solutions of the desired gimbal angles are simple to get for a desired target direction specified in the spacecraft body fame. If the gimbal axes and the antenna boresight are slightly misaligned, the nominal closed-form solution is not sufficiently accurate for computing the gimbal angles needed to point at a target. In this situation, either a general closed-form solution has to be developed for a mechanism with general geometries, or a correction scheme has to be applied to the nominal closed-form solutions. The latter has been adopted for Solar Dynamics Observatory (SDO) as can be seen in Reference 1, and the former has been used for LRO. The advantage of the general closed-form solution is the use of a small number of parameters for the correction of nominal solutions, especially in the regions near singularities. Singularities here refer to cases when the nominal closed-form solutions have two or more solutions. Algorithm complexity, however, is the disadvantage of the general closed-form solution.

Narrow Angle movie

NASA Technical Reports Server (NTRS)

1999-01-01

This brief three-frame movie of the Moon was made from three Cassini narrow-angle images as the spacecraft passed by the Moon on the way to its closest approach with Earth on August 17, 1999. The purpose of this particular set of images was to calibrate the spectral response of the narrow-angle camera and to test its 'on-chip summing mode' data compression technique in flight. From left to right, they show the Moon in the green, blue and ultraviolet regions of the spectrum in 40, 60 and 80 millisecond exposures, respectively. All three images have been scaled so that the brightness of Crisium basin, the dark circular region in the upper right, is the same in each image. The spatial scale in the blue and ultraviolet images is 1.4 miles per pixel (2.3 kilometers). The original scale in the green image (which was captured in the usual manner and then reduced in size by 2x2 pixel summing within the camera system) was 2.8 miles per pixel (4.6 kilometers). It has been enlarged for display to the same scale as the other two. The imaging data were processed and released by the Cassini Imaging Central Laboratory for Operations (CICLOPS) at the University of Arizona's Lunar and Planetary Laboratory, Tucson, AZ.

Photo Credit: NASA/JPL/Cassini Imaging Team/University of Arizona

Cassini, launched in 1997, is a joint mission of NASA, the European Space Agency and Italian Space Agency. The mission is managed by NASA's Jet Propulsion Laboratory, Pasadena, CA, for NASA's Office of Space Science, Washington DC. JPL is a division of the California Institute of Technology, Pasadena, CA.

ARC-1985-A86-7001

NASA Image and Video Library

1985-11-28

Range: 72.3 million km. ( 44.9 million miles ) P-29314B/W This Voyager 2 photograph of Uranus shows the planets outermost, or epsilon, ring. This is a computerized summation of six images shot by the narrow angle camera. It is the first photo to show the epsilon ring unblurred by Earth's atmosphere. The Epsilon ring, some 51,200 km. ( 31,800 miles ) from the planets center, is the most prominent of Uranus' nine known rings. Ground based observations of stellar occulations by the rings have determined that the Epsilon ring is eccentric, or elliptical, with its widest portion about 100 km. ( 60 miles ) wide and its narrowest portion about 20 km. (12 miles ). Estimates of the rings brightness suggest that it is also very dark, with a reflectance of only 1 or 2 percent and a probable composition of carbonaceous material similiar to that on dark asteroids and the dark side of Saturn's moon Lapetus. Because the ring is so narrow and dark, at this range, the Voyager camera could not resolve even the widest part, resulting in long exposure times so obtain a good image. six exposures of 11 or 15 second duration were added together by computer to produce this image. In this image, the central portion is greatly overexposed. Various artifacts due to electronic effects and image proccessing can be seen in the central portion of the frame, including the dark image just above the planets image, the diffuse brightening below it and the small, bright projection from the edge of the planet in the upper left. The ring is distinctly less prominent in the lower left portion and more prominent in the upper right. This is in agreement with the predicted locations of the narrow and wide portions of the ring, respectively.

Arne - Exploring the Mare Tranquillitatis Pit

NASA Astrophysics Data System (ADS)

Robinson, M. S.; Thangavelautham, J.; Wagner, R.; Hernandez, V. A.; Finch, J.

2014-12-01

Lunar mare "pits" are key science and exploration targets. The first three pits were discovered within Selene observations [1,2] and were proposed to represent collapses into lava tubes. Subsequent LROC images revealed 5 new mare pits and showed that the Mare Tranquillitatis pit (MTP; 8.335°N, 33.222°E) opens into a sublunarean void at least 20-meters in extent [3,4]. A key remaining task is determining pit subsurface extents, and thus fully understanding their exploration and scientific value. We propose a simple and cost effective reconnaissance of the MTP using a small lander (<130 kg) named Arne, that carries three flying microbots (or pit-bots) [5,6,7]. Key measurement objectives include decimeter scale characterization of the pit walls, 5-cm scale imaging of the eastern floor, determination of the extent of sublunarean void(s), and measurement of the magnetic and thermal environment. After landing and initial surface systems check Arne will transmit full resolution descent and surface images. Within two hours the first pit-bot will launch and fly into the eastern void. Depending on results from the first pit-bot the second and third will launch and perform follow-up observations. The primary mission is expected to last 48-hours; before the Sun sets on the lander there should be enough time to execute ten flights with each pit-bot. The pit-bots are 30-cm diameter spherical flying robots [5,6,7] equipped with stereo cameras, temperature sensors, sensors for obstacle avoidance and a laser rangefinder. Lithium hydride [5,6] and water/hydrogen peroxide power three micro-thrusters and achieve a specific impulse of 350-400 s. Each pit-bot can fly for 2 min at 2 m/s for more than 100 cycles; recharge time is 20 min. Arne will carry a magnetometer, thermometer, 2 high resolution cameras, and 6 wide angle cameras and obstacle avoidance infrared sensors enabling detailed characterization of extant sublunarean voids. [1] Haruyama et al. (2010) 41st LPSC, #1285. [2] Haruyama et al. (2010) GRL, 36, dx.doi.org/ 10.1029/2009GL0406355. [3] Robinson et al (2012) PSS, 69, dx.doi.org/ 10.1016/j.pss.2012.05.008 [4] Wagner and Robinson (2014) Icarus, dx.doi.org/10.1016/j.icarus.2014.04.002. [5] Thangavelautham et al. (2012) IEEE ICRA [6] Strawser et al. (2014) J. Hydrogen Energy. [7] Dubowsky et al. (2007) Proc. CLAWAR.

KSC-2009-3177

NASA Image and Video Library

2009-05-15

CAPE CANAVERAL, Fla. – At Astrotech Space Operations Facility in Titusville, Fla., garbed media representatives attend a showing of NASA's Lunar Reconnaissance Orbiter, or LRO, and NASA's Lunar Crater Observation and Sensing Satellite, known as LCROSS. The LRO includes five instruments: DIVINER, LAMP, LEND, LOLA and LROC. They will be launched aboard an Atlas V/Centaur rocket no earlier than June 17 from Launch Complex-41 on Cape Canaveral Air Force Station in Florida. Photo credit: NASA/Jack Pfaller

KSC-2009-3178

NASA Image and Video Library

2009-05-15

CAPE CANAVERAL, Fla. – At Astrotech Space Operations Facility in Titusville, Fla., NASA's Lunar Reconnaissance Orbiter, or LRO, and NASA's Lunar Crater Observation and Sensing Satellite, known as LCROSS, are being prepared for fairing installation. The LRO includes five instruments: DIVINER, LAMP, LEND, LOLA and LROC. They will be launched aboard an Atlas V/Centaur rocket no earlier than June 17 from Launch Complex-41 on Cape Canaveral Air Force Station in Florida. Photo credit: NASA/Jack Pfaller

Video-CRM: understanding customer behaviors in stores

NASA Astrophysics Data System (ADS)

Haritaoglu, Ismail; Flickner, Myron; Beymer, David

2013-03-01

This paper describes two real-time computer vision systems created 10 years ago that detect and track people in stores to obtain insights of customer behavior while shopping. The first system uses a single color camera to identify shopping groups in the checkout line. Shopping groups are identified by analyzing the inter-body distances coupled with the cashier's activities to detect checkout transactions start and end times. The second system uses multiple overhead narrow-baseline stereo cameras to detect and track people, their body posture and parts to understand customer interactions with products such as "customer picking a product from a shelf". In pilot studies both systems demonstrated real-time performance and sufficient accuracy to enable more detailed understanding of customer behavior and extract actionable real-time retail analytics.

Influence of Needle Tip Distance on Barrier Discharge and Ozone Generation for Multiple Needles-Plane Electrode Configuration

NASA Astrophysics Data System (ADS)

Ueno, Hideki; Kawahara, Shintaro; Nakayama, Hiroshi

Relationship between barrier discharge characteristics and ozone generation under ac voltage application on triple needles-plane configuration has been investigated for various distances among triple needle-tips (d=0 ∼ 7.0mm) at constant distance between needle tip and plane (g=3.0mm) in dry air. Characteristics of barrier discharge and ozone generation depend on the needle-tips distance. It is considered that the influence is caused by space charge and accumulated charge suggested from discharge image by still camera and CCD camera. And ozone generation efficiency is also estimated by power consumption and ozone concentration. As a result, when the distance among triple needle-tips is narrow, the above-mentioned influence is strengthened. And in this case, ozone generation efficiency is improved.

Airborne Open Polar/Imaging Nephelometer for Ice Particles in Cirrus Clouds and Aerosols Field Campaign Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Martins, JV

2016-04-01

The Open Imaging Nephelometer (O-I-Neph) instrument is an adaptation of a proven laboratory instrument built and tested at the University of Maryland, Baltimore County (UMBC), the Polarized Imaging Nephelometer (PI-Neph). The instrument design of both imaging nephelometers uses a narrow-beam laser source and a wide-field-of-view imaging camera to capture the entire scattering-phase function in one image, quasi-instantaneously.

Thermal Control of the Scientific Instrument Package in the Large Space Telescope

NASA Technical Reports Server (NTRS)

Hawks, K. H.

1972-01-01

The general thermal control system philosophy was to utilize passive control where feasible and to utilize active methods only where required for more accurate thermal control of the SIP components with narrow temperature tolerances. A thermal model of the SIP and a concept for cooling the SIP cameras are presented. The model and cooling concept have established a rationale for determining a Phase A baseline for SIP thermal control.

Observations of localized NiII emission in M82: Evidence for supernovae activity in the molecular cloud east of the nucleus

NASA Technical Reports Server (NTRS)

Rank, David M.; Temi, Pasquale; Bregman, Jesse D.; Dunham, Edward W.; Harker, David

1995-01-01

Narrow band images of M82 at wavelengths of 6.63 microns (NiII) and 6.8 microns (continuum) are discussed in terms of new evidence for supernova activity in the nuclear region of the M82 starburst galaxy. Data were recorded using a 128x128 Si:Ga array in an infrared camera on the KAO Southern Expedition in April '94.

Mapping Boron Dioxide (BO2) Light Emission During Ballistic Initiation of Boron

DTIC Science & Technology

2016-03-03

Dreizin; unreferenced). Essentially, 2 light sensors (cameras), each filtered over a narrow wavelength region, observe an event over the same line of...background incandescence (subtraction gave a qualitatively similar result). For imaging BO2 emission, the light sensors were 2 Phantom V7.3 monochrome...A check of the temperature measurement technique using emission from an acetylene/air diffusion flame gave reasonable results (1,800 K outer soot

Dust mass distribution around comet 67P/Churyumov-Gerasimenko determined via parallax measurements using Rosetta's OSIRIS cameras

NASA Astrophysics Data System (ADS)

Ott, T.; Drolshagen, E.; Koschny, D.; Güttler, C.; Tubiana, C.; Frattin, E.; Agarwal, J.; Sierks, H.; Bertini, I.; Barbieri, C.; Lamy, P. I.; Rodrigo, R.; Rickman, H.; A'Hearn, M. F.; Barucci, M. A.; Bertaux, J.-L.; Boudreault, S.; Cremonese, G.; Da Deppo, V.; Davidsson, B.; Debei, S.; De Cecco, M.; Deller, J.; Feller, C.; Fornasier, S.; Fulle, M.; Geiger, B.; Gicquel, A.; Groussin, O.; Gutiérrez, P. J.; Hofmann, M.; Hviid, S. F.; Ip, W.-H.; Jorda, L.; Keller, H. U.; Knollenberg, J.; Kovacs, G.; Kramm, J. R.; Kührt, E.; Küppers, M.; Lara, L. M.; Lazzarin, M.; Lin, Z.-Y.; López-Moreno, J. J.; Marzari, F.; Mottola, S.; Naletto, G.; Oklay, N.; Pajola, M.; Shi, X.; Thomas, N.; Vincent, J.-B.; Poppe, B.

2017-07-01

The OSIRIS (optical, spectroscopic and infrared remote imaging system) instrument on board the ESA Rosetta spacecraft collected data of 67P/Churyumov-Gerasimenko for over 2 yr. OSIRIS consists of two cameras, a Narrow Angle Camera and a Wide Angle Camera. For specific imaging sequences related to the observation of dust aggregates in 67P's coma, the two cameras were operating simultaneously. The two cameras are mounted 0.7 m apart from each other, as a result this baseline yields a parallax shift of the apparent particle trails on the analysed images directly proportional to their distance. Thanks to such shifts, the distance between observed dust aggregates and the spacecraft was determined. This method works for particles closer than 6000 m to the spacecraft and requires very few assumptions. We found over 250 particles in a suitable distance range with sizes of some centimetres, masses in the range of 10-6-102 kg and a mean velocity of about 2.4 m s-1 relative to the nucleus. Furthermore, the spectral slope was analysed showing a decrease in the median spectral slope of the particles with time. The further a particle is from the spacecraft the fainter is its signal. For this reason, this was counterbalanced by a debiasing. Moreover, the dust mass-loss rate of the nucleus could be computed as well as the Afρ of the comet around perihelion. The summed-up dust mass-loss rate for the mass bins 10-4-102 kg is almost 8300 kg s-1.

The Moon Zoo citizen science project: Preliminary results for the Apollo 17 landing site

NASA Astrophysics Data System (ADS)

Bugiolacchi, Roberto; Bamford, Steven; Tar, Paul; Thacker, Neil; Crawford, Ian A.; Joy, Katherine H.; Grindrod, Peter M.; Lintott, Chris

2016-06-01

Moon Zoo is a citizen science project that utilises internet crowd-sourcing techniques. Moon Zoo users are asked to review high spatial resolution images from the Lunar Reconnaissance Orbiter Camera (LROC), onboard NASA's LRO spacecraft, and perform characterisation such as measuring impact crater sizes and identify morphological 'features of interest'. The tasks are designed to address issues in lunar science and to aid future exploration of the Moon. We have tested various methodologies and parameters therein to interrogate and reduce the Moon Zoo crater location and size dataset against a validated expert survey. We chose the Apollo 17 region as a test area since it offers a broad range of cratered terrains, including secondary-rich areas, older maria, and uplands. The assessment involved parallel testing in three key areas: (1) filtering of data to remove problematic mark-ups; (2) clustering methods of multiple notations per crater; and (3) derivation of alternative crater degradation indices, based on the statistical variability of multiple notations and the smoothness of local image structures. We compared different combinations of methods and parameters and assessed correlations between resulting crater summaries and the expert census. We derived the optimal data reduction steps and settings of the existing Moon Zoo crater data to agree with the expert census. Further, the regolith depth and crater degradation states derived from the data are also found to be in broad agreement with other estimates for the Apollo 17 region. Our study supports the validity of this citizen science project but also recommends improvements in key elements of the data acquisition planning and production.

Robotic Camera Assistance and Its Benefit in 1033 Traditional Laparoscopic Procedures: Prospective Clinical Trial Using a Joystick-guided Camera Holder.

PubMed

Holländer, Sebastian W; Klingen, Hans Joachim; Fritz, Marliese; Djalali, Peter; Birk, Dieter

2014-11-01

Despite advances in instruments and techniques in laparoscopic surgery, one thing remains uncomfortable: the camera assistance. The aim of this study was to investigate the benefit of a joystick-guided camera holder (SoloAssist®, Aktormed, Barbing, Germany) for laparoscopic surgery and to compare the robotic assistance to human assistance. 1033 consecutive laparoscopic procedures were performed assisted by the SoloAssist®. Failures and aborts were documented and nine surgeons were interviewed by questionnaire regarding their experiences. In 71 of 1033 procedures, robotic assistance was aborted and the procedure was continued manually, mostly because of frequent changes of position, narrow spaces, and adverse angular degrees. One case of short circuit was reported. Emergency stop was necessary in three cases due to uncontrolled movement into the abdominal cavity. Eight of nine surgeons prefer robotic to human assistance, mostly because of a steady image and self-control. The SoloAssist® robot is a reliable system for laparoscopic procedures. Emergency shutdown was necessary in only three cases. Some minor weak spots could have been identified. Most surgeons prefer robotic assistance to human assistance. We feel that the SoloAssist® makes standard laparoscopic surgery more comfortable and further development is desirable, but it cannot fully replace a human assistant.

Improved TDEM formation using fused ladar/digital imagery from a low-cost small UAV

NASA Astrophysics Data System (ADS)

Khatiwada, Bikalpa; Budge, Scott E.

2017-05-01

Formation of a Textured Digital Elevation Model (TDEM) has been useful in many applications in the fields of agriculture, disaster response, terrain analysis and more. Use of a low-cost small UAV system with a texel camera (fused lidar/digital imagery) can significantly reduce the cost compared to conventional aircraft-based methods. This paper reports continued work on this problem reported in a previous paper by Bybee and Budge, and reports improvements in performance. A UAV fitted with a texel camera is flown at a fixed height above the terrain and swaths of texel image data of the terrain below is taken continuously. Each texel swath has one or more lines of lidar data surrounded by a narrow strip of EO data. Texel swaths are taken such that there is some overlap from one swath to its adjacent swath. The GPS/IMU fitted on the camera also give coarse knowledge of attitude and position. Using this coarse knowledge and the information from the texel image, the error in the camera position and attitude is reduced which helps in producing an accurate TDEM. This paper reports improvements in the original work by using multiple lines of lidar data per swath. The final results are shown and analyzed for numerical accuracy.

Two Titans

NASA Image and Video Library

2017-08-11

These two views of Saturn's moon Titan exemplify how NASA's Cassini spacecraft has revealed the surface of this fascinating world. Cassini carried several instruments to pierce the veil of hydrocarbon haze that enshrouds Titan. The mission's imaging cameras also have several spectral filters sensitive to specific wavelengths of infrared light that are able to make it through the haze to the surface and back into space. These "spectral windows" have enable the imaging cameras to map nearly the entire surface of Titan. In addition to Titan's surface, images from both the imaging cameras and VIMS have provided windows into the moon's ever-changing atmosphere, chronicling the appearance and movement of hazes and clouds over the years. A large, bright and feathery band of summer clouds can be seen arcing across high northern latitudes in the view at right. These views were obtained with the Cassini spacecraft narrow-angle camera on March 21, 2017. Images taken using red, green and blue spectral filters were combined to create the natural-color view at left. The false-color view at right was made by substituting an infrared image (centered at 938 nanometers) for the red color channel. The views were acquired at a distance of approximately 613,000 miles (986,000 kilometers) from Titan. Image scale is about 4 miles (6 kilometers) per pixel. https://photojournal.jpl.nasa.gov/catalog/PIA21624

KSC-2009-3296

NASA Image and Video Library

2009-05-28

CAPE CANAVERAL, Fla. – The Lunar Reconnaissance Orbiter, or LRO, and NASA's Lunar Crater Observation and Sensing Satellite, known as LCROSS, are moved closer to the mobile service tower on Launch Complex 41 at Cape Canaveral Air Force Station in Florida. The LRO includes five instruments that will help NASA characterize the moon's surface: DIVINER, LAMP, LEND, LOLA and LROC. Along with LCROSS, they will be launched aboard an Atlas V/Centaur rocket on June 17. Photo credit: NASA/Dimitri Gerondidakis

KSC-2009-3295

NASA Image and Video Library

2009-05-28

CAPE CANAVERAL, Fla. – The Lunar Reconnaissance Orbiter, or LRO, and NASA's Lunar Crater Observation and Sensing Satellite, known as LCROSS, arrive on Launch Complex 41 at Cape Canaveral Air Force Station in Florida. Surrounding the launch pad are the lightning protection towers. The LRO includes five instruments that will help NASA characterize the moon's surface: DIVINER, LAMP, LEND, LOLA and LROC. Along with LCROSS, they will be launched aboard an Atlas V/Centaur rocket on June 17. Photo credit: NASA/Dimitri Gerondidakis

A preliminary optical design for the JANUS camera of ESA's space mission JUICE

NASA Astrophysics Data System (ADS)

Greggio, D.; Magrin, D.; Ragazzoni, R.; Munari, M.; Cremonese, G.; Bergomi, M.; Dima, M.; Farinato, J.; Marafatto, L.; Viotto, V.; Debei, S.; Della Corte, V.; Palumbo, P.; Hoffmann, H.; Jaumann, R.; Michaelis, H.; Schmitz, N.; Schipani, P.; Lara, L.

2014-08-01

The JANUS (Jovis, Amorum ac Natorum Undique Scrutator) will be the on board camera of the ESA JUICE satellite dedicated to the study of Jupiter and its moons, in particular Ganymede and Europa. This optical channel will provide surface maps with plate scale of 15 microrad/pixel with both narrow and broad band filters in the spectral range between 0.35 and 1.05 micrometers over a Field of View 1.72 × 1.29 degrees2. The current optical design is based on TMA design, with on-axis pupil and off-axis field of view. The optical stop is located at the secondary mirror providing an effective collecting area of 7854 mm2 (100 mm entrance pupil diameter) and allowing a simple internal baffling for first order straylight rejection. The nominal optical performances are almost limited by the diffraction and assure a nominal MTF better than 63% all over the whole Field of View. We describe here the optical design of the camera adopted as baseline together with the trade-off that has led us to this solution.

Effects of gap width on droplet transfer behavior in ultra-narrow gap laser welding of high strength aluminum alloys

NASA Astrophysics Data System (ADS)

Song, Chaoqun; Dong, Shiyun; Yan, Shixing; He, Jiawu; Xu, Binshi; He, Peng

2017-10-01

Ultra-narrow gap laser welding is a novel method for thick high strength aluminum alloy plate for its lower heat input, less deformation and higher efficiency. To obtain a perfect welding quality, it is vital to control the more complex droplet transfer behavior under the influence of ultra-narrow gap groove. This paper reports the effects of gap width of groove on droplet transfer behavior in ultra-narrow gap laser welding of 7A52 aluminum alloy plates by a high speed camera, using an ER 5356 filler wire. The results showed that the gap width had directly effects on droplet transfer mode and droplet shape. The droplet transfer modes were, in order, both-sidewall transfer, single-sidewall transfer, globular droplet transfer and bridging transfer, with different droplet shape and transition period, as the gap width increased from 2 mm to 3.5mm. The effect of gap width on lack of fusion was also studied to analyze the cause for lack of fusion at the bottom and on the sidewall of groove. Finally, with a 2.5 mm U-type parallel groove, a single-pass joint with no lack of fusion and other macro welding defects was successfully obtained in a single-sidewall transfer mode.

The Si/CdTe semiconductor Compton camera of the ASTRO-H Soft Gamma-ray Detector (SGD)

NASA Astrophysics Data System (ADS)

Watanabe, Shin; Tajima, Hiroyasu; Fukazawa, Yasushi; Ichinohe, Yuto; Takeda, Shin`ichiro; Enoto, Teruaki; Fukuyama, Taro; Furui, Shunya; Genba, Kei; Hagino, Kouichi; Harayama, Atsushi; Kuroda, Yoshikatsu; Matsuura, Daisuke; Nakamura, Ryo; Nakazawa, Kazuhiro; Noda, Hirofumi; Odaka, Hirokazu; Ohta, Masayuki; Onishi, Mitsunobu; Saito, Shinya; Sato, Goro; Sato, Tamotsu; Takahashi, Tadayuki; Tanaka, Takaaki; Togo, Atsushi; Tomizuka, Shinji

2014-11-01

The Soft Gamma-ray Detector (SGD) is one of the instrument payloads onboard ASTRO-H, and will cover a wide energy band (60-600 keV) at a background level 10 times better than instruments currently in orbit. The SGD achieves low background by combining a Compton camera scheme with a narrow field-of-view active shield. The Compton camera in the SGD is realized as a hybrid semiconductor detector system which consists of silicon and cadmium telluride (CdTe) sensors. The design of the SGD Compton camera has been finalized and the final prototype, which has the same configuration as the flight model, has been fabricated for performance evaluation. The Compton camera has overall dimensions of 12 cm×12 cm×12 cm, consisting of 32 layers of Si pixel sensors and 8 layers of CdTe pixel sensors surrounded by 2 layers of CdTe pixel sensors. The detection efficiency of the Compton camera reaches about 15% and 3% for 100 keV and 511 keV gamma rays, respectively. The pixel pitch of the Si and CdTe sensors is 3.2 mm, and the signals from all 13,312 pixels are processed by 208 ASICs developed for the SGD. Good energy resolution is afforded by semiconductor sensors and low noise ASICs, and the obtained energy resolutions with the prototype Si and CdTe pixel sensors are 1.0-2.0 keV (FWHM) at 60 keV and 1.6-2.5 keV (FWHM) at 122 keV, respectively. This results in good background rejection capability due to better constraints on Compton kinematics. Compton camera energy resolutions achieved with the final prototype are 6.3 keV (FWHM) at 356 keV and 10.5 keV (FWHM) at 662 keV, which satisfy the instrument requirements for the SGD Compton camera (better than 2%). Moreover, a low intrinsic background has been confirmed by the background measurement with the final prototype.

Using spectral information in forensic imaging.

PubMed

Miskelly, Gordon M; Wagner, John H

2005-12-20

Improved detection of forensic evidence by combining narrow band photographic images taken at a range of wavelengths is dependent on the substance of interest having a significantly different spectrum from the underlying substrate. While some natural substances such as blood have distinctive spectral features which are readily distinguished from common colorants, this is not true for visualization agents commonly used in forensic science. We now show that it is possible to select reagents with narrow spectral features that lead to increased visibility using digital cameras and computer image enhancement programs even if their coloration is much less intense to the unaided eye than traditional reagents. The concept is illustrated by visualising latent fingermarks on paper with the zinc complex of Ruhemann's Purple, cyanoacrylate-fumed fingerprints with Eu(tta)(3)(phen), and soil prints with 2,6-bis(benzimidazol-2-yl)-4-[4'-(dimethylamino)phenyl]pyridine [BBIDMAPP]. In each case background correction is performed at one or two wavelengths bracketing the narrow absorption or emission band of these compounds. However, compounds with sharp spectral features would also lead to improved detection using more advanced algorithms such as principal component analysis.

Study on airflow characteristics in the semi-closed irregular narrow flow channel

NASA Astrophysics Data System (ADS)

Jin, Yuzhen; Hu, Xiaodong; Zhu, Linhang; Hu, Xudong; Jin, Yingzi

2016-04-01

The air-jet loom is widely used in the textile industry. The interaction mechanism of airflow and yarn is not clear in such a narrow flow channel, the gas consumption is relatively large, the yarn motion is unstable and the weft insertion is often interrupted during the operation. In order to study the characteristics of the semi-closed flow field in profiled dents, the momentum conservation equation is modified and the model parameters and boundary conditions are set. Compared with the different r, the ratio of profiled dent's thickness and gap, the results show that the smaller the r is, the smaller the velocity fluctuations of the airflow is. When the angle of profiled dents α is close to zero, the diffusion of the airflow will be less. The experiment is also conducted to verify the result of the simulation with a high-speed camera and pressure sensor in profiled dents. The airflow characteristics in the semi-closed irregular narrow flow channel in the paper would provide the theoretical basis for optimizing the weft insertion process of the air-jet loom.

Visibility through the gaseous smoke in airborne remote sensing using a DSLR camera

NASA Astrophysics Data System (ADS)

Chabok, Mirahmad; Millington, Andrew; Hacker, Jorg M.; McGrath, Andrew J.

2016-08-01

Visibility and clarity of remotely sensed images acquired by consumer grade DSLR cameras, mounted on an unmanned aerial vehicle or a manned aircraft, are critical factors in obtaining accurate and detailed information from any area of interest. The presence of substantial haze, fog or gaseous smoke particles; caused, for example, by an active bushfire at the time of data capture, will dramatically reduce image visibility and quality. Although most modern hyperspectral imaging sensors are capable of capturing a large number of narrow range bands of the shortwave and thermal infrared spectral range, which have the potential to penetrate smoke and haze, the resulting images do not contain sufficient spatial detail to enable locating important objects or assist search and rescue or similar applications which require high resolution information. We introduce a new method for penetrating gaseous smoke without compromising spatial resolution using a single modified DSLR camera in conjunction with image processing techniques which effectively improves the visibility of objects in the captured images. This is achieved by modifying a DSLR camera and adding a custom optical filter to enable it to capture wavelengths from 480-1200nm (R, G and Near Infrared) instead of the standard RGB bands (400-700nm). With this modified camera mounted on an aircraft, images were acquired over an area polluted by gaseous smoke from an active bushfire. Processed data using our proposed method shows significant visibility improvements compared with other existing solutions.

Advances in Heavy Ion Beam Probe Technology and Operation on MST

NASA Astrophysics Data System (ADS)

Demers, D. R.; Connor, K. A.; Schoch, P. M.; Radke, R. J.; Anderson, J. K.; Craig, D.; den Hartog, D. J.

2003-10-01

A technique to map the magnetic field of a plasma via spectral imaging is being developed with the Heavy Ion Beam Probe on the Madison Symmetric Torus. The technique will utilize two-dimensional images of the ion beam in the plasma, acquired by two CCD cameras, to generate a three-dimensional reconstruction of the beam trajectory. This trajectory, and the known beam ion mass, energy and charge-state, will be used to determine the magnetic field of the plasma. A suitable emission line has not yet been observed since radiation from the MST plasma is both broadband and intense. An effort to raise the emission intensity from the ion beam by increasing beam focus and current has been undertaken. Simulations of the accelerator ion optics and beam characteristics led to a technique, confirmed by experiment, that achieves a narrower beam and marked increase in ion current near the plasma surface. The improvements arising from these simulations will be discussed. Realization of the magnetic field mapping technique is contingent upon accurate reconstruction of the beam trajectory from the camera images. Simulations of two camera CCD images, including the interior of MST, its various landmarks and beam trajectories have been developed. These simulations accept user input such as camera locations, resolution via pixellization and noise. The quality of the images simulated with these and other variables will help guide the selection of viewing port pairs, image size and camera specifications. The results of these simulations will be presented.

Spectroscopic Study of a Pulsed High-Energy Plasma Deflagration Accelerator

NASA Astrophysics Data System (ADS)

Loebner, Keith; Underwood, Thomas; Mouratidis, Theodore; Cappelli, Mark

2015-11-01

Observations of broadened Balmer lines emitted by a highly-ionized transient plasma jet are presented. A gated CCD camera coupled to a high-resolution spectrometer is used to obtain chord-averaged broadening data for a complete cross section of the plasma jet, and the data is Abel inverted to derive the radial plasma density distribution. This measurement is performed over narrow gate widths and at multiple axial positions to provide high spatial and temporal resolution. A streak camera coupled to a spectrometer is used to obtain continuous-time broadening data over the entire duration of the discharge event (10-50 microseconds). Analyses of discharge characteristics and comparisons with previous work are discussed. This work is supported by the U.S. Department of Energy Stewardship Science Academic Program, as well as the National Defense Science Engineering Graduate Fellowship.

Navigation of a care and welfare robot

NASA Astrophysics Data System (ADS)

Yukawa, Toshihiro; Hosoya, Osamu; Saito, Naoki; Okano, Hideharu

2005-12-01

In this paper, we propose the development of a robot that can perform nursing tasks in a hospital. In a narrow environment such as a sickroom or a hallway, the robot must be able to move freely in arbitrary directions. Therefore, the robot needs to have high controllability and the capability to make precise movements. Our robot can recognize a line by using cameras, and can be controlled in the reference directions by means of comparison with original cell map information; furthermore, it moves safely on the basis of an original center-line established permanently in the building. Correspondence between the robot and a centralized control center enables the robot's autonomous movement in the hospital. Through a navigation system using cell map information, the robot is able to perform nursing tasks smoothly by changing the camera angle.

Velocity visualization in gaseous flows

NASA Technical Reports Server (NTRS)

Hanson, R. K.

1985-01-01

Techniques are established for visualizing velocity in gaseous flows. Two approaches are considered, both of which are capable of yielding velocity simultaneously at a large number of flowfield locations, thereby providing images of velocity. The first technique employs a laser to mark specific fluid elements and a camera to track their subsequent motion. Marking is done by laser-induced phosphorescence of biacetyl, added as a tracer species in a flow of N2, or by laser-induced formation of sulfur particulates in SF6-H2-N2 mixtures. The second technique is based on the Doppler effect, and uses an intensified photodiode array camera and a planar form of laser-induced fluorescence to detect 2-d velocities of I2 (in I2-N2 mixtures) via Doppler-shifted absorption of narrow-linewidth laser radiation at 514.5 nm.

Economical Emission-Line Mapping: ISM Properties of Nearby Protogalaxy Analogs

NASA Astrophysics Data System (ADS)

Monkiewicz, Jacqueline A.

2017-01-01

Optical emission line imaging can produce a wealth of information about the conditions of the interstellar medium, but a full set of custom emission-line filters for a professional-grade telescope camera can cost many thousands of dollars. A cheaper alternative is to use commercially-produced 2-inch narrow-band astrophotography filters. In order to use these standardized filters with professional-grade telescope cameras, custom filter mounts must be manufactured for each individual filter wheel. These custom filter adaptors are produced by 3-D printing rather than standard machining, which further lowers the total cost.I demonstrate the feasibility of this technique with H-alpha, H-beta, and [OIII] emission line mapping of the low metallicity star-forming galaxies IC10 and NGC 1569, taken with my astrophotography filter set on three different 2-meter class telescopes in Southern Arizona.

How to track protists in three dimensions

NASA Astrophysics Data System (ADS)

Drescher, Knut; Leptos, Kyriacos C.; Goldstein, Raymond E.

2009-01-01

We present an apparatus optimized for tracking swimming micro-organisms in the size range of 10-1000 μm, in three dimensions (3Ds), far from surfaces, and with negligible background convective fluid motion. Charge coupled device cameras attached to two long working distance microscopes synchronously image the sample from two perpendicular directions, with narrow band dark-field or bright-field illumination chosen to avoid triggering a phototactic response. The images from the two cameras can be combined to yield 3D tracks of the organism. Using additional, highly directional broad-spectrum illumination with millisecond timing control the phototactic trajectories in 3D of organisms ranging from Chlamydomonas to Volvox can be studied in detail. Surface-mediated hydrodynamic interactions can also be investigated without convective interference. Minimal modifications to the apparatus allow for studies of chemotaxis and other taxes.

Upgrading and testing program for narrow band high resolution planetary IR imaging spectrometer

NASA Technical Reports Server (NTRS)

Wattson, R. B.; Rappaport, S.

1977-01-01

An imaging spectrometer, intended primarily for observations of the outer planets, which utilizes an acoustically tuned optical filter (ATOF) and a charge coupled device (CCD) television camera was modified to improve spatial resolution and sensitivity. The upgraded instrument was a spatial resolving power of approximately 1 arc second, as defined by an f/7 beam at the CCD position and it has this resolution over the 50 arc second field of view. Less vignetting occurs and sensitivity is four times greater. The spectral resolution of 15 A over the wavelength interval 6500 A - 11,000 A is unchanged. Mechanical utility has been increased by the use of a honeycomb optical table, mechanically rigid yet adjustable optical component mounts, and a camera focus translation stage. The upgraded instrument was used to observe Venus and Saturn.

First light observations with TIFR Near Infrared Imaging Camera (TIRCAM-II)

NASA Astrophysics Data System (ADS)

Ojha, D. K.; Ghosh, S. K.; D'Costa, S. L. A.; Naik, M. B.; Sandimani, P. R.; Poojary, S. S.; Bhagat, S. B.; Jadhav, R. B.; Meshram, G. S.; Bakalkar, C. B.; Ramaprakash, A. N.; Mohan, V.; Joshi, J.

TIFR near infrared imaging camera (TIRCAM-II) is based on the Aladdin III Quadrant InSb focal plane array (512×512 pixels; 27.6 μm pixel size; sensitive between 1 - 5.5 μm). TIRCAM-II had its first engineering run with the 2 m IUCAA telescope at Girawali during February - March 2011. The first light observations with TIRCAM-II were quite successful. Several infrared standard with TIRCAM-II were quite successful. Several infrared standard stars, the Trapezium Cluster in Orion region, McNeil's nebula, etc., were observed in the J, K and in a narrow-band at 3.6 μm (nbL). In the nbL band, some bright stars could be detected from the Girawali site. The performance of TIRCAM-II is discussed in the light of preliminary observations in near infrared bands.

Multi-pinhole collimator design for small-object imaging with SiliSPECT: a high-resolution SPECT

NASA Astrophysics Data System (ADS)

Shokouhi, S.; Metzler, S. D.; Wilson, D. W.; Peterson, T. E.

2009-01-01

We have designed a multi-pinhole collimator for a dual-headed, stationary SPECT system that incorporates high-resolution silicon double-sided strip detectors. The compact camera design of our system enables imaging at source-collimator distances between 20 and 30 mm. Our analytical calculations show that using knife-edge pinholes with small-opening angles or cylindrically shaped pinholes in a focused, multi-pinhole configuration in combination with this camera geometry can generate narrow sensitivity profiles across the field of view that can be useful for imaging small objects at high sensitivity and resolution. The current prototype system uses two collimators each containing 127 cylindrically shaped pinholes that are focused toward a target volume. Our goal is imaging objects such as a mouse brain, which could find potential applications in molecular imaging.

Technique for compressing light intensity ranges utilizing a specifically designed liquid crystal notch filter

DOEpatents

Rushford, Michael C.

1988-01-01

A pin hole camera assembly for use in viewing an object having a relatively large light intensity range, for example a crucible containing molten metal in an atomic vapor laser isotope separation (AVLIS) system is disclosed herein. The assembly includes means for optically compressing the light intensity range appearing at its input sufficient to make it receivable and decipherable by a standard video camera. To accomplish this, the assembly utilizes the combination of interference filter and a liquid crystal notch filter. The latter which preferably includes a cholesteric liquid crystal arrangement is configured to pass light at all wavelengths, except a relatively narrow wavelength band which defines the filter's notch, and includes means for causing the notch to vary to at least a limited extent with the intensity of light at its light incidence surface.

KSC-2009-3300

NASA Image and Video Library

2009-05-28

CAPE CANAVERAL, Fla. – On Launch Complex 41 at Cape Canaveral Air Force Station in Florida, workers check out the Lunar Reconnaissance Orbiter, or LRO, after its lift into the mobile service tower. The LRO/LCROSS will be mated to the Atlas V rocket for launch. The LRO includes five instruments that will help NASA characterize the moon's surface: DIVINER, LAMP, LEND, LOLA and LROC. Along with LCROSS, they will be launched aboard an Atlas V/Centaur rocket on June 17. Photo credit: NASA/Dimitri Gerondidakis

KSC-2009-3293

NASA Image and Video Library

2009-05-28

CAPE CANAVERAL, Fla. – Encased in the fairing, the Lunar Reconnaissance Orbiter, or LRO, and NASA's Lunar Crater Observation and Sensing Satellite, known as LCROSS, are moved out of Astrotech Space Operations in Titusville. It is being transported to Launch Complex 41 at Cape Canaveral Air Force Station in Florida. The LRO includes five instruments that will help NASA characterize the moon's surface: DIVINER, LAMP, LEND, LOLA and LROC. Along with LCROSS, they will be launched aboard an Atlas V/Centaur rocket on June 17. Photo credit: NASA/Dimitri Gerondidakis

KSC-2009-3294

NASA Image and Video Library

2009-05-28

CAPE CANAVERAL, Fla. – Enroute to Launch Complex 41 at Cape Canaveral Air Force Station in Florida, the Lunar Reconnaissance Orbiter, or LRO, and NASA's Lunar Crater Observation and Sensing Satellite, known as LCROSS, move past the Vehicle Assembly Building at NASA's Kennedy Space Center in Florida. The LRO includes five instruments that will help NASA characterize the moon's surface: DIVINER, LAMP, LEND, LOLA and LROC. Along with LCROSS, they will be launched aboard an Atlas V/Centaur rocket on June 17. Photo credit: NASA/Dimitri Gerondidakis

KSC-2009-3299

NASA Image and Video Library

2009-05-28

CAPE CANAVERAL, Fla. – On Launch Complex 41 at Cape Canaveral Air Force Station in Florida, the Lunar Reconnaissance Orbiter, or LRO, and NASA's Lunar Crater Observation and Sensing Satellite, known as LCROSS, are moved into the mobile service tower. The LRO will be mated to the Atlas V rocket for launch. The LRO includes five instruments that will help NASA characterize the moon's surface: DIVINER, LAMP, LEND, LOLA and LROC. Along with LCROSS, they will be launched aboard an Atlas V/Centaur rocket on June 17. Photo credit: NASA/Dimitri Gerondidakis

KSC-2009-3303

NASA Image and Video Library

2009-05-28

CAPE CANAVERAL, Fla. – On Launch Complex 41 at Cape Canaveral Air Force Station in Florida, the Lunar Reconnaissance Orbiter, or LRO, and NASA's Lunar Crater Observation and Sensing Satellite, known as LCROSS, are mated with the Atlas V rocket inside the mobile service tower for launch. The LRO includes five instruments that will help NASA characterize the moon's surface: DIVINER, LAMP, LEND, LOLA and LROC. Along with LCROSS, they will be launched aboard an Atlas V/Centaur rocket on June 17. Photo credit: NASA/Dimitri Gerondidakis

KSC-2009-3301

NASA Image and Video Library

2009-05-28

CAPE CANAVERAL, Fla. – On Launch Complex 41 at Cape Canaveral Air Force Station in Florida, workers prepare the Lunar Reconnaissance Orbiter, or LRO, and NASA's Lunar Crater Observation and Sensing Satellite, known as LCROSS, for mating inside the mobile service tower with the Atlas V rocket for launch. The LRO includes five instruments that will help NASA characterize the moon's surface: DIVINER, LAMP, LEND, LOLA and LROC. Along with LCROSS, they will be launched aboard an Atlas V/Centaur rocket on June 17. Photo credit: NASA/Dimitri Gerondidakis

KSC-2009-3302

NASA Image and Video Library

2009-05-28

CAPE CANAVERAL, Fla. – On Launch Complex 41 at Cape Canaveral Air Force Station in Florida, the Lunar Reconnaissance Orbiter, or LRO, and NASA's Lunar Crater Observation and Sensing Satellite, known as LCROSS, are mated with the Atlas V rocket inside the mobile service tower for launch. The LRO includes five instruments that will help NASA characterize the moon's surface: DIVINER, LAMP, LEND, LOLA and LROC. Along with LCROSS, they will be launched aboard an Atlas V/Centaur rocket on June 17. Photo credit: NASA/Dimitri Gerondidakis

KSC-2009-3292

NASA Image and Video Library

2009-05-28

CAPE CANAVERAL, Fla. – Encased in the fairing, the Lunar Reconnaissance Orbiter, or LRO, and NASA's Lunar Crater Observation and Sensing Satellite, known as LCROSS, are moved out of Astrotech Space Operations in Titusville. It is being transported to Launch Complex 41 at Cape Canaveral Air Force Station in Florida. The LRO includes five instruments that will help NASA characterize the moon's surface: DIVINER, LAMP, LEND, LOLA and LROC. Along with LCROSS, they will be launched aboard an Atlas V/Centaur rocket on June 17. Photo credit: NASA/Dimitri Gerondidakis

Thermal Effects on Camera Focal Length in Messenger Star Calibration and Orbital Imaging

NASA Astrophysics Data System (ADS)

Burmeister, S.; Elgner, S.; Preusker, F.; Stark, A.; Oberst, J.

2018-04-01

We analyse images taken by the MErcury Surface, Space ENviorment, GEochemistry, and Ranging (MESSENGER) spacecraft for the camera's thermal response in the harsh thermal environment near Mercury. Specifically, we study thermally induced variations in focal length of the Mercury Dual Imaging System (MDIS). Within the several hundreds of images of star fields, the Wide Angle Camera (WAC) typically captures up to 250 stars in one frame of the panchromatic channel. We measure star positions and relate these to the known star coordinates taken from the Tycho-2 catalogue. We solve for camera pointing, the focal length parameter and two non-symmetrical distortion parameters for each image. Using data from the temperature sensors on the camera focal plane we model a linear focal length function in the form of f(T) = A0 + A1 T. Next, we use images from MESSENGER's orbital mapping mission. We deal with large image blocks, typically used for the production of a high-resolution digital terrain models (DTM). We analyzed images from the combined quadrangles H03 and H07, a selected region, covered by approx. 10,600 images, in which we identified about 83,900 tiepoints. Using bundle block adjustments, we solved for the unknown coordinates of the control points, the pointing of the camera - as well as the camera's focal length. We then fit the above linear function with respect to the focal plane temperature. As a result, we find a complex response of the camera to thermal conditions of the spacecraft. To first order, we see a linear increase by approx. 0.0107 mm per degree temperature for the Narrow-Angle Camera (NAC). This is in agreement with the observed thermal response seen in images of the panchromatic channel of the WAC. Unfortunately, further comparisons of results from the two methods, both of which use different portions of the available image data, are limited. If leaving uncorrected, these effects may pose significant difficulties in the photogrammetric analysis, specifically these may be responsible for erroneous longwavelength trends in topographic models.

The Europa Imaging System (EIS): Investigating Europa's geology, ice shell, and current activity

NASA Astrophysics Data System (ADS)

Turtle, Elizabeth; Thomas, Nicolas; Fletcher, Leigh; Hayes, Alexander; Ernst, Carolyn; Collins, Geoffrey; Hansen, Candice; Kirk, Randolph L.; Nimmo, Francis; McEwen, Alfred; Hurford, Terry; Barr Mlinar, Amy; Quick, Lynnae; Patterson, Wes; Soderblom, Jason

2016-07-01

NASA's Europa Mission, planned for launch in 2022, will perform more than 40 flybys of Europa with altitudes at closest approach as low as 25 km. The instrument payload includes the Europa Imaging System (EIS), a camera suite designed to transform our understanding of Europa through global decameter-scale coverage, topographic and color mapping, and unprecedented sub- meter-scale imaging. EIS combines narrow-angle and wide-angle cameras to address these science goals: • Constrain the formation processes of surface features by characterizing endogenic geologic structures, surface units, global cross-cutting relationships, and relationships to Europa's subsurface structure and potential near-surface water. • Search for evidence of recent or current activity, including potential plumes. • Characterize the ice shell by constraining its thickness and correlating surface features with subsurface structures detected by ice penetrating radar. • Characterize scientifically compelling landing sites and hazards by determining the nature of the surface at scales relevant to a potential lander. EIS Narrow-angle Camera (NAC): The NAC, with a 2.3°° x 1.2°° field of view (FOV) and a 10-μμrad instantaneous FOV (IFOV), achieves 0.5-m pixel scale over a 2-km-wide swath from 50-km altitude. A 2-axis gimbal enables independent targeting, allowing very high-resolution stereo imaging to generate digital topographic models (DTMs) with 4-m spatial scale and 0.5-m vertical precision over the 2-km swath from 50-km altitude. The gimbal also makes near-global (>95%) mapping of Europa possible at ≤50-m pixel scale, as well as regional stereo imaging. The NAC will also perform high-phase-angle observations to search for potential plumes. EIS Wide-angle Camera (WAC): The WAC has a 48°° x 24°° FOV, with a 218-μμrad IFOV, and is designed to acquire pushbroom stereo swaths along flyby ground-tracks. From an altitude of 50 km, the WAC achieves 11-m pixel scale over a 44-km-wide swath, generating DTMs with 32-m spatial scale and 4-m vertical precision. These data also support characterization of surface clutter for interpretation of radar deep and shallow sounding modes. Detectors: The cameras have identical rapid-readout, radiation-hard 4k x 2k CMOS detectors and can image in both pushbroom and framing modes. Color observations are acquired by pushbroom imaging using six broadband filters (~300-1050 nm), allowing mapping of surface units for correlation with geologic structures, topography, and compositional units from other instruments.

Development of a CCD based solar speckle imaging system

NASA Astrophysics Data System (ADS)

Nisenson, Peter; Stachnik, Robert V.; Noyes, Robert W.

1986-02-01

A program to develop software and hardware for the purpose of obtaining high angular resolution images of the solar surface is described. The program included the procurement of a Charge Coupled Devices imaging system; an extensive laboratory and remote site testing of the camera system; the development of a software package for speckle image reconstruction which was eventually installed and tested at the Sacramento Peak Observatory; and experiments of the CCD system (coupled to an image intensifier) for low light level, narrow spectral band solar imaging.

Mid infra-red hyper-spectral imaging with bright super continuum source and fast acousto-optic tuneable filter for cytological applications.

NASA Astrophysics Data System (ADS)

Farries, Mark; Ward, Jon; Valle, Stefano; Stephens, Gary; Moselund, Peter; van der Zanden, Koen; Napier, Bruce

2015-06-01

Mid-IR imaging spectroscopy has the potential to offer an effective tool for early cancer diagnosis. Current development of bright super-continuum sources, narrow band acousto-optic tunable filters and fast cameras have made feasible a system that can be used for fast diagnosis of cancer in vivo at point of care. The performance of a proto system that has been developed under the Minerva project is described.

LOFT. Mobile test building (TAN624) is recycled from ANP program ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

LOFT. Mobile test building (TAN-624) is recycled from ANP program for placement before LOFT containment building door. It has not yet been connected to containment building. Note borated water tank at right of dome. Narrow, vertical structure at right of door is shroud is shroud for air exhaust duct. Filter vaults lie between duct shroud and stack. Camera facing westerly. Date: 1974. INEEL negative no. 74-1072 - Idaho National Engineering Laboratory, Test Area North, Scoville, Butte County, ID

Nonlinear dynamic range transformation in visual communication channels.

PubMed

Alter-Gartenberg, R

1996-01-01

The article evaluates nonlinear dynamic range transformation in the context of the end-to-end continuous-input/discrete processing/continuous-display imaging process. Dynamic range transformation is required when we have the following: (i) the wide dynamic range encountered in nature is compressed into the relatively narrow dynamic range of the display, particularly for spatially varying irradiance (e.g., shadow); (ii) coarse quantization is expanded to the wider dynamic range of the display; and (iii) nonlinear tone scale transformation compensates for the correction in the camera amplifier.

Integration of multispectral face recognition and multi-PTZ camera automated surveillance for security applications

NASA Astrophysics Data System (ADS)

Chen, Chung-Hao; Yao, Yi; Chang, Hong; Koschan, Andreas; Abidi, Mongi

2013-06-01

Due to increasing security concerns, a complete security system should consist of two major components, a computer-based face-recognition system and a real-time automated video surveillance system. A computerbased face-recognition system can be used in gate access control for identity authentication. In recent studies, multispectral imaging and fusion of multispectral narrow-band images in the visible spectrum have been employed and proven to enhance the recognition performance over conventional broad-band images, especially when the illumination changes. Thus, we present an automated method that specifies the optimal spectral ranges under the given illumination. Experimental results verify the consistent performance of our algorithm via the observation that an identical set of spectral band images is selected under all tested conditions. Our discovery can be practically used for a new customized sensor design associated with given illuminations for an improved face recognition performance over conventional broad-band images. In addition, once a person is authorized to enter a restricted area, we still need to continuously monitor his/her activities for the sake of security. Because pantilt-zoom (PTZ) cameras are capable of covering a panoramic area and maintaining high resolution imagery for real-time behavior understanding, researches in automated surveillance systems with multiple PTZ cameras have become increasingly important. Most existing algorithms require the prior knowledge of intrinsic parameters of the PTZ camera to infer the relative positioning and orientation among multiple PTZ cameras. To overcome this limitation, we propose a novel mapping algorithm that derives the relative positioning and orientation between two PTZ cameras based on a unified polynomial model. This reduces the dependence on the knowledge of intrinsic parameters of PTZ camera and relative positions. Experimental results demonstrate that our proposed algorithm presents substantially reduced computational complexity and improved flexibility at the cost of slightly decreased pixel accuracy as compared to Chen and Wang's method [18].

A new star tracker concept for satellite attitude determination based on a multi-purpose panoramic camera

NASA Astrophysics Data System (ADS)

Opromolla, Roberto; Fasano, Giancarmine; Rufino, Giancarlo; Grassi, Michele; Pernechele, Claudio; Dionisio, Cesare

2017-11-01

This paper presents an innovative algorithm developed for attitude determination of a space platform. The algorithm exploits images taken from a multi-purpose panoramic camera equipped with hyper-hemispheric lens and used as star tracker. The sensor architecture is also original since state-of-the-art star trackers accurately image as many stars as possible within a narrow- or medium-size field-of-view, while the considered sensor observes an extremely large portion of the celestial sphere but its observation capabilities are limited by the features of the optical system. The proposed original approach combines algorithmic concepts, like template matching and point cloud registration, inherited from the computer vision and robotic research fields, to carry out star identification. The final aim is to provide a robust and reliable initial attitude solution (lost-in-space mode), with a satisfactory accuracy level in view of the multi-purpose functionality of the sensor and considering its limitations in terms of resolution and sensitivity. Performance evaluation is carried out within a simulation environment in which the panoramic camera operation is realistically reproduced, including perturbations in the imaged star pattern. Results show that the presented algorithm is able to estimate attitude with accuracy better than 1° with a success rate around 98% evaluated by densely covering the entire space of the parameters representing the camera pointing in the inertial space.

High Dynamic Imaging for Photometry and Graphic Arts Evaluation

NASA Astrophysics Data System (ADS)

T. S., Sudheer Kumar; Kurian, Ciji Pearl; Shama, Kumara; K. R., Shailesh

2018-05-01

High Dynamic Range Imaging (HDRI) techniques for luminance measurement is gaining importance in recent years. This paper presents the application of the HDRI system for obtaining the photometric characteristics of lighting fixtures as well to assess the quality of lighting in colour viewing booth of a printing press. The process of quality control of prints in a printing press is known as graphic arts evaluation. This light booth plays a major role in the quality control of prints. In this work, Nikon D5100 camera was used to obtain the photometric characteristics of narrow beam spotlight. The results of this experiment are in agreement with photometric characteristics obtained from a standard industry grade Gonio-photometer. Similarly, Canon 60D camera was used to assess the quality of spatial luminance distribution of light in the colour viewing booth. This work demonstrates the usefulness of HDRI technology for photometric measurements and luminance distributions of illuminated interiors.

Overview of diagnostic implementation on Proto-MPEX at ORNL

NASA Astrophysics Data System (ADS)

Biewer, T. M.; Bigelow, T.; Caughman, J. B. O.; Fehling, D.; Goulding, R. H.; Gray, T. K.; Isler, R. C.; Martin, E. H.; Meitner, S.; Rapp, J.; Unterberg, E. A.; Dhaliwal, R. S.; Donovan, D.; Kafle, N.; Ray, H.; Shaw, G. C.; Showers, M.; Mosby, R.; Skeen, C.

2015-11-01

The Prototype Material Plasma Exposure eXperiment (Proto-MPEX) recently began operating with an expanded diagnostic set. Approximately 100 sightlines have been established, delivering the plasma light emission to a ``patch panel'' in the diagnostic room for distribution to a variety of instruments: narrow-band filter spectroscopy, Doppler spectroscopy, laser induced breakdown spectroscopy, optical emission spectroscopy, and Thomson scattering. Additional diagnostic systems include: IR camera imaging, in-vessel thermocouples, ex-vessel fluoroptic probes, fast pressure gauges, visible camera imaging, microwave interferometry, a retarding-field energy analyzer, rf-compensated and ``double'' Langmuir probes, and B-dot probes. A data collection and archival system has been initiated using the MDSplus format. This effort capitalizes on a combination of new and legacy diagnostic hardware at ORNL and was accomplished largely through student labor. This work was supported by the US. D.O.E. contract DE-AC05-00OR22725.

Still from High-Clouds Jupiter Movie

NASA Technical Reports Server (NTRS)

2000-01-01

This image is one of seven from the narrow-angle camera on NASA's Cassini spacecraft assembled as a brief movie of high-altitude cloud movements on Jupiter. It was taken in early October 2000.

The images were taken at a wavelength that is absorbed by methane, one chemical in Jupiter's lower clouds. So, dark areas are relatively free of high clouds, and the camera sees through to the methane in a lower level. Bright areas are places with high, thick clouds that shield the methane below.

The area shown covers latitudes from 50 degrees north to 50 degrees south and a 100-degree sweep of longitude.

Cassini is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Cassini mission for NASA's Office of Space Science, Washington, D.C.

Fixed-Wing Micro Aerial Vehicle for Accurate Corridor Mapping

NASA Astrophysics Data System (ADS)

Rehak, M.; Skaloud, J.

2015-08-01

In this study we present a Micro Aerial Vehicle (MAV) equipped with precise position and attitude sensors that together with a pre-calibrated camera enables accurate corridor mapping. The design of the platform is based on widely available model components to which we integrate an open-source autopilot, customized mass-market camera and navigation sensors. We adapt the concepts of system calibration from larger mapping platforms to MAV and evaluate them practically for their achievable accuracy. We present case studies for accurate mapping without ground control points: first for a block configuration, later for a narrow corridor. We evaluate the mapping accuracy with respect to checkpoints and digital terrain model. We show that while it is possible to achieve pixel (3-5 cm) mapping accuracy in both cases, precise aerial position control is sufficient for block configuration, the precise position and attitude control is required for corridor mapping.

Small-Scale Features in Pulsating Aurora

NASA Technical Reports Server (NTRS)

Jones, Sarah; Jaynes, Allison N.; Knudsen, David J.; Trondsen, Trond; Lessard, Marc

2011-01-01

A field study was conducted from March 12-16, 2002 using a narrow-field intensified CCD camera installed at Churchill, Manitoba. The camera was oriented along the local magnetic zenith where small-scale black auroral forms are often visible. This analysis focuses on such forms occurring within a region of pulsating aurora. The observations show black forms with irregular shape and nonuniform drift with respect to the relatively stationary pulsating patches. The pulsating patches occur within a diffuse auroral background as a modulation of the auroral brightness in a localized region. The images analyzed show a decrease in the brightness of the diffuse background in the region of the pulsating patch at the beginning of the offphase of the modulation. Throughout the off phase the brightness of the diffuse aurora gradually increases back to the average intensity. The time constant for this increase is measured as the first step toward determining the physical process.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Moore, A. S., E-mail: alastair.moore@physics.org; Ahmed, M. F.; Soufli, R.

A dual-channel streaked soft x-ray imager has been designed and used on high energy-density physics experiments at the National Ignition Facility. This streaked imager creates two images of the same x-ray source using two slit apertures and a single shallow angle reflection from a nickel mirror. Thin filters are used to create narrow band pass images at 510 eV and 360 eV. When measuring a Planckian spectrum, the brightness ratio of the two images can be translated into a color-temperature, provided that the spectral sensitivity of the two images is well known. To reduce uncertainty and remove spectral features inmore » the streak camera photocathode from this photon energy range, a thin 100 nm CsI on 50 nm Al streak camera photocathode was implemented. Provided that the spectral shape is well-known, then uncertainties on the spectral sensitivity limits the accuracy of the temperature measurement to approximately 4.5% at 100 eV.« less

The soft gamma-ray detector (SGD) onboard ASTRO-H

NASA Astrophysics Data System (ADS)

Watanabe, Shin; Tajima, Hiroyasu; Fukazawa, Yasushi; Blandford, Roger; Enoto, Teruaki; Goldwurm, Andrea; Hagino, Kouichi; Hayashi, Katsuhiro; Ichinohe, Yuto; Kataoka, Jun; Katsuta, Junichiro; Kitaguchi, Takao; Kokubun, Motohide; Laurent, Philippe; Lebrun, François; Limousin, Olivier; Madejski, Grzegorz M.; Makishima, Kazuo; Mizuno, Tsunefumi; Mori, Kunishiro; Nakamori, Takeshi; Nakano, Toshio; Nakazawa, Kazuhiro; Noda, Hirofumu; Odaka, Hirokazu; Ohno, Masanori; Ohta, Masayuki; Saito, Shinya; Sato, Goro; Sato, Rie; Takeda, Shin'ichiro; Takahashi, Hiromitsu; Takahashi, Tadayuki; Tanaka, Takaaki; Tanaka, Yasuyuki; Terada, Yukikatsu; Uchiyama, Hideki; Uchiyama, Yasunobu; Yamaoka, Kazutaka; Yatsu, Yoichi; Yonetoku, Daisuke; Yuasa, Takayuki

2016-07-01

The Soft Gamma-ray Detector (SGD) is one of science instruments onboard ASTRO-H (Hitomi) and features a wide energy band of 60{600 keV with low backgrounds. SGD is an instrument with a novel concept of "Narrow field-of-view" Compton camera where Compton kinematics is utilized to reject backgrounds which are inconsistent with the field-of-view defined by the active shield. After several years of developments, the flight hardware was fabricated and subjected to subsystem tests and satellite system tests. After a successful ASTRO-H (Hitomi) launch on February 17, 2016 and a critical phase operation of satellite and SGD in-orbit commissioning, the SGD operation was moved to the nominal observation mode on March 24, 2016. The Compton cameras and BGO-APD shields of SGD worked properly as designed. On March 25, 2016, the Crab nebula observation was performed, and, the observation data was successfully obtained.

Colorful Saturn, Getting Closer

NASA Image and Video Library

2004-06-03

As Cassini coasts into the final month of its nearly seven-year trek, the serene majesty of its destination looms ahead. The spacecraft's cameras are functioning beautifully and continue to return stunning views from Cassini's position, 1.2 billion kilometers (750 million miles) from Earth and now 15.7 million kilometers (9.8 million miles) from Saturn. In this narrow angle camera image from May 21, 2004, the ringed planet displays subtle, multi-hued atmospheric bands, colored by yet undetermined compounds. Cassini mission scientists hope to determine the exact composition of this material. This image also offers a preview of the detailed survey Cassini will conduct on the planet's dazzling rings. Slight differences in color denote both differences in ring particle composition and light scattering properties. Images taken through blue, green and red filters were combined to create this natural color view. The image scale is 132 kilometers (82 miles) per pixel. http://photojournal.jpl.nasa.gov/catalog/PIA06060

Faint Object Camera imaging and spectroscopy of NGC 4151

NASA Technical Reports Server (NTRS)

Boksenberg, A.; Catchpole, R. M.; Macchetto, F.; Albrecht, R.; Barbieri, C.; Blades, J. C.; Crane, P.; Deharveng, J. M.; Disney, M. J.; Jakobsen, P.

1995-01-01

We describe ultraviolet and optical imaging and spectroscopy within the central few arcseconds of the Seyfert galaxy NGC 4151, obtained with the Faint Object Camera on the Hubble Space Telescope. A narrowband image including (O III) lambda(5007) shows a bright nucleus centered on a complex biconical structure having apparent opening angle approximately 65 deg and axis at a position angle along 65 deg-245 deg; images in bands including Lyman-alpha and C IV lambda(1550) and in the optical continuum near 5500 A, show only the bright nucleus. In an off-nuclear optical long-slit spectrum we find a high and a low radial velocity component within the narrow emission lines. We identify the low-velocity component with the bright, extended, knotty structure within the cones, and the high-velocity component with more confined diffuse emission. Also present are strong continuum emission and broad Balmer emission line components, which we attribute to the extended point spread function arising from the intense nuclear emission. Adopting the geometry pointed out by Pedlar et al. (1993) to explain the observed misalignment of the radio jets and the main optical structure we model an ionizing radiation bicone, originating within a galactic disk, with apex at the active nucleus and axis centered on the extended radio jets. We confirm that through density bounding the gross spatial structure of the emission line region can be reproduced with a wide opening angle that includes the line of sight, consistent with the presence of a simple opaque torus allowing direct view of the nucleus. In particular, our modelling reproduces the observed decrease in position angle with distance from the nucleus, progressing initially from the direction of the extended radio jet, through our optical structure, and on to the extended narrow-line region. We explore the kinematics of the narrow-line low- and high-velocity components on the basis of our spectroscopy and adopted model structure.

Opposition effect of the Moon from LROC WAC data

NASA Astrophysics Data System (ADS)

Velikodsky, Yu. I.; Korokhin, V. V.; Shkuratov, Yu. G.; Kaydash, V. G.; Videen, Gorden

2016-09-01

LROC WAC images acquired in 5 bands of the visible spectral range were used to study the opposition effect for two mare and two highland regions near the lunar equator. Opposition phase curves were extracted from the images containing the opposition by separating the phase-curve effect from the albedo pattern by comparing WAC images at different phase angles (from 0° to 30°). Akimov's photometric function and the NASA Digital Terrain Model GLD100 were used in the processing. It was found that phase-curve slopes at small phase angles directly correlate with albedo, while at larger phase angles, they are anti-correlated. We suggest a parameter to characterize the coherent-backscattering component of the lunar opposition surge, which is defined as the maximum phase angle for which the opposition-surge slope increases with growing albedo. The width of the coherent-backscattering opposition effect varies from approximately 1.2° for highlands in red light to 3.9° for maria in blue light. The parameter depends on albedo, which is in agreement with the coherent-backscattering theory. The maximum amplitude of the coherent opposition effect is estimated to be near 8%. Maps of albedo and phase-curve slope at phase angles larger than those, at which the coherent-backscattering occurs, were built for the areas under study. Absolute calibration of WAC images was compared with Earth-based observations: the WAC-determined albedo is very close to the mean lunar albedo calculated using available Earth-based observations.

Differentiating Biological Colours with Few and Many Sensors: Spectral Reconstruction with RGB and Hyperspectral Cameras

PubMed Central

Garcia, Jair E.; Girard, Madeline B.; Kasumovic, Michael; Petersen, Phred; Wilksch, Philip A.; Dyer, Adrian G.

2015-01-01

Background The ability to discriminate between two similar or progressively dissimilar colours is important for many animals as it allows for accurately interpreting visual signals produced by key target stimuli or distractor information. Spectrophotometry objectively measures the spectral characteristics of these signals, but is often limited to point samples that could underestimate spectral variability within a single sample. Algorithms for RGB images and digital imaging devices with many more than three channels, hyperspectral cameras, have been recently developed to produce image spectrophotometers to recover reflectance spectra at individual pixel locations. We compare a linearised RGB and a hyperspectral camera in terms of their individual capacities to discriminate between colour targets of varying perceptual similarity for a human observer. Main Findings (1) The colour discrimination power of the RGB device is dependent on colour similarity between the samples whilst the hyperspectral device enables the reconstruction of a unique spectrum for each sampled pixel location independently from their chromatic appearance. (2) Uncertainty associated with spectral reconstruction from RGB responses results from the joint effect of metamerism and spectral variability within a single sample. Conclusion (1) RGB devices give a valuable insight into the limitations of colour discrimination with a low number of photoreceptors, as the principles involved in the interpretation of photoreceptor signals in trichromatic animals also apply to RGB camera responses. (2) The hyperspectral camera architecture provides means to explore other important aspects of colour vision like the perception of certain types of camouflage and colour constancy where multiple, narrow-band sensors increase resolution. PMID:25965264

Best practices to optimize intraoperative photography.

PubMed

Gaujoux, Sébastien; Ceribelli, Cecilia; Goudard, Geoffrey; Khayat, Antoine; Leconte, Mahaut; Massault, Pierre-Philippe; Balagué, Julie; Dousset, Bertrand

2016-04-01

Intraoperative photography is used extensively for communication, research, or teaching. The objective of the present work was to define, using a standardized methodology and literature review, the best technical conditions for intraoperative photography. Using either a smartphone camera, a bridge camera, or a single-lens reflex (SLR) camera, photographs were taken under various standard conditions by a professional photographer. All images were independently assessed blinded to technical conditions to define the best shooting conditions and methods. For better photographs, an SLR camera with manual settings should be used. Photographs should be centered and taken vertically and orthogonal to the surgical field with a linear scale to avoid error in perspective. The shooting distance should be about 75 cm using an 80-100-mm focal lens. Flash should be avoided and scialytic low-powered light should be used without focus. The operative field should be clean, wet surfaces should be avoided, and metal instruments should be hidden to avoid reflections. For SLR camera, International Organization for Standardization speed should be as low as possible, autofocus area selection mode should be on single point AF, shutter speed should be above 1/100 second, and aperture should be as narrow as possible, above f/8. For smartphone, use high dynamic range setting if available, use of flash, digital filter, effect apps, and digital zoom is not recommended. If a few basic technical rules are known and applied, high-quality photographs can be taken by amateur photographers and fit the standards accepted in clinical practice, academic communication, and publications. Copyright © 2016 Elsevier Inc. All rights reserved.

In-Flight performance of MESSENGER's Mercury dual imaging system

USGS Publications Warehouse

Hawkins, S.E.; Murchie, S.L.; Becker, K.J.; Selby, C.M.; Turner, F.S.; Noble, M.W.; Chabot, N.L.; Choo, T.H.; Darlington, E.H.; Denevi, B.W.; Domingue, D.L.; Ernst, C.M.; Holsclaw, G.M.; Laslo, N.R.; Mcclintock, W.E.; Prockter, L.M.; Robinson, M.S.; Solomon, S.C.; Sterner, R.E.

2009-01-01

The Mercury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) spacecraft, launched in August 2004 and planned for insertion into orbit around Mercury in 2011, has already completed two flybys of the innermost planet. The Mercury Dual Imaging System (MDIS) acquired nearly 2500 images from the first two flybys and viewed portions of Mercury's surface not viewed by Mariner 10 in 1974-1975. Mercury's proximity to the Sun and its slow rotation present challenges to the thermal design for a camera on an orbital mission around Mercury. In addition, strict limitations on spacecraft pointing and the highly elliptical orbit create challenges in attaining coverage at desired geometries and relatively uniform spatial resolution. The instrument designed to meet these challenges consists of dual imagers, a monochrome narrow-angle camera (NAC) with a 1.5?? field of view (FOV) and a multispectral wide-angle camera (WAC) with a 10.5?? FOV, co-aligned on a pivoting platform. The focal-plane electronics of each camera are identical and use a 1024??1024 charge-coupled device detector. The cameras are passively cooled but use diode heat pipes and phase-change-material thermal reservoirs to maintain the thermal configuration during the hot portions of the orbit. Here we present an overview of the instrument design and how the design meets its technical challenges. We also review results from the first two flybys, discuss the quality of MDIS data from the initial periods of data acquisition and how that compares with requirements, and summarize how in-flight tests are being used to improve the quality of the instrument calibration. ?? 2009 SPIE.

Detection of pointing errors with CMOS-based camera in intersatellite optical communications

NASA Astrophysics Data System (ADS)

Yu, Si-yuan; Ma, Jing; Tan, Li-ying

2005-01-01

For very high data rates, intersatellite optical communications hold a potential performance edge over microwave communications. Acquisition and Tracking problem is critical because of the narrow transmit beam. A single array detector in some systems performs both spatial acquisition and tracking functions to detect pointing errors, so both wide field of view and high update rate is required. The past systems tend to employ CCD-based camera with complex readout arrangements, but the additional complexity reduces the applicability of the array based tracking concept. With the development of CMOS array, CMOS-based cameras can employ the single array detector concept. The area of interest feature of the CMOS-based camera allows a PAT system to specify portion of the array. The maximum allowed frame rate increases as the size of the area of interest decreases under certain conditions. A commercially available CMOS camera with 105 fps @ 640×480 is employed in our PAT simulation system, in which only part pixels are used in fact. Beams angle varying in the field of view can be detected after getting across a Cassegrain telescope and an optical focus system. Spot pixel values (8 bits per pixel) reading out from CMOS are transmitted to a DSP subsystem via IEEE 1394 bus, and pointing errors can be computed by the centroid equation. It was shown in test that: (1) 500 fps @ 100×100 is available in acquisition when the field of view is 1mrad; (2)3k fps @ 10×10 is available in tracking when the field of view is 0.1mrad.

Space telescope optical telescope assembly/scientific instruments. Phase B: Preliminary design and program definition study. Volume 2A(3): Astrometry

NASA Technical Reports Server (NTRS)

1976-01-01

Wide field measurements, namely, measurements of relative angular separations between stars over a relatively wide field for parallax and proper motion determinations, were made with the third fine guidance sensor. Narrow field measurements, i.e., double star measurements, are accomplished primarily with the area photometer or faint object camera at f/96. The wavelength range required can be met by the fine guidance sensor which has a spectral coverage from 3000 to 7500 A. The field of view of the fine guidance sensor also exceeds that required for the wide field astrometric instrument. Requirements require a filter wheel for the wide field astrometer, and so one was incorporated into the design of the fine guidance sensor. The filter wheel probably would contain two neutral density filters to extend the dynamic range of the sensor and three spectral filters for narrowing effective double star magnitude difference.

Visual imaging control systems of the Mariner to Jupiter and Saturn spacecraft

NASA Technical Reports Server (NTRS)

Larks, L.

1979-01-01

Design and fabrication of optical systems for the Mariner Jupiter Saturn (Voyager) mission is described. Because of the long distances of these planets from the sun, the spacecraft was designed without solar panels with the electricity generated on-board by radio-isotope thermal generators (RTG). The presence of RTG's and Jupiter radiation environment required that the optical systems be fabricated out of radiation stabilized materials. A narrow angle and a wide angle camera are located on the spacecraft scan platform, with the narrow angle lens a modification of the Mariner 10 lens. The optical system is described, noting that the lens was modified by moving the aperture correctors forward and placing a spider mounted secondary mirror in the original back surface of the second aperture corrector. The wide angle lens was made out of cerium doped, radiation stabilized optical glass with greatest blue transmittance, which would be resistant to RTG and Jupiter radiation.

ARC-1986-A86-7022

NASA Image and Video Library

1986-01-25

P-29506BW Range: 1.12 million kilometers (690,000 miles) This high-resolution image of the epsilon ring of Uranus is a clear-filter picture from Voyager's narrow-angle camera and has a resolution of about 10 km (6 mi). The epsilon ring, approx. 100 km (60 mi) wide at this location, clearly shows a structural variation. Visible here are a broad, bright outer component about 40 km (25 mi) wide; a darker, middle region of comparable width; and a narrow, bright inner strip about 15 km (9 mi) wide. The epsilon-ring structure seen by Voyager is similiar to that observed from the ground with stellar-occultation techniques. This frame represents the first Voyager image that resolves these features within the epsilon ring. The occasional fuzzy splotches on the outer and innerparts of the ring are artifacts left by the removal of reseau marks (used for making measurements on the image).

Narrow-Band Organic Photodiodes for High-Resolution Imaging.

PubMed

Han, Moon Gyu; Park, Kyung-Bae; Bulliard, Xavier; Lee, Gae Hwang; Yun, Sungyoung; Leem, Dong-Seok; Heo, Chul-Joon; Yagi, Tadao; Sakurai, Rie; Ro, Takkyun; Lim, Seon-Jeong; Sul, Sangchul; Na, Kyoungwon; Ahn, Jungchak; Jin, Yong Wan; Lee, Sangyoon

2016-10-05

There are growing opportunities and demands for image sensors that produce higher-resolution images, even in low-light conditions. Increasing the light input areas through 3D architecture within the same pixel size can be an effective solution to address this issue. Organic photodiodes (OPDs) that possess wavelength selectivity can allow for advancements in this regard. Here, we report on novel push-pull D-π-A dyes specially designed for Gaussian-shaped, narrow-band absorption and the high photoelectric conversion. These p-type organic dyes work both as a color filter and as a source of photocurrents with linear and fast light responses, high sensitivity, and excellent stability, when combined with C60 to form bulk heterojunctions (BHJs). The effectiveness of the OPD composed of the active color filter was demonstrated by obtaining a full-color image using a camera that contained an organic/Si hybrid complementary metal-oxide-semiconductor (CMOS) color image sensor.

Lonely Moon

NASA Image and Video Library

2016-10-17

Pandora is seen here, in isolation beside Saturn's kinked and constantly changing F ring. Pandora (near upper right) is 50 miles (81 kilometers) wide. The moon has an elongated, potato-like shape (see PIA07632). Two faint ringlets are visible within the Encke Gap, near lower left. The gap is about 202 miles (325 kilometers) wide. The much narrower Keeler Gap, which lies outside the Encke Gap, is maintained by the diminutive moon Daphnis (not seen here). This view looks toward the sunlit side of the rings from about 23 degrees above the ring plane. The image was taken in visible light with the Cassini spacecraft narrow-angle camera on Aug. 12, 2016. The view was acquired at a distance of approximately 907,000 miles (1.46 million kilometers) from Saturn and at a Sun-Saturn-spacecraft, or phase, angle of 113 degrees. Image scale is 6 miles (9 kilometers) per pixel. http://photojournal.jpl.nasa.gov/catalog/PIA20504

Calibrating the PAU Survey's 46 Filters

NASA Astrophysics Data System (ADS)

Bauer, A.; Castander, F.; Gaztañaga, E.; Serrano, S.; Sevilla, N.; Tonello, N.; PAU Team

2016-05-01

The Physics of the Accelerating Universe (PAU) Survey, being carried out by several Spanish institutions, will image an area of 100-200 square degrees in 6 broad and 40 narrow band optical filters. The team is building a camera (PAUCam) with 18 CCDs, which will be installed in the 4 meter William Herschel Telescope at La Palma in 2013. The narrow band filters will each cover 100Å, with the set spanning 4500-8500Å. The broad band set will consist of standard ugriZy filters. The narrow band filters will provide low-resolution (R˜50) photometric "spectra" for all objects observed in the survey, which will reach a depth of ˜24 mag in the broad bands and ˜22.5 mag (AB) in the narrow bands. Such precision will allow for galaxy photometric redshift errors of 0.0035(1+z), which will facilitate the measurement of cosmological parameters with precision comparable to much larger spectroscopic and photometric surveys. Accurate photometric calibration of the PAU data is vital to the survey's science goals, and is not straightforward due to the large and unusual filter set. We outline the data management pipelines being developed for the survey, both for nightly data reduction and coaddition of multiple epochs, with emphasis on the photometric calibration strategies. We also describe the tools we are developing to test the quality of the reduction and calibration.

LROC Investigation of Three Strategies for Reducing the Impact of Respiratory Motion on the Detection of Solitary Pulmonary Nodules in SPECT

NASA Astrophysics Data System (ADS)

Smyczynski, Mark S.; Gifford, Howard C.; Dey, Joyoni; Lehovich, Andre; McNamara, Joseph E.; Segars, W. Paul; King, Michael A.

2016-02-01

The objective of this investigation was to determine the effectiveness of three motion reducing strategies in diminishing the degrading impact of respiratory motion on the detection of small solitary pulmonary nodules (SPNs) in single-photon emission computed tomographic (SPECT) imaging in comparison to a standard clinical acquisition and the ideal case of imaging in the absence of respiratory motion. To do this nonuniform rational B-spline cardiac-torso (NCAT) phantoms based on human-volunteer CT studies were generated spanning the respiratory cycle for a normal background distribution of Tc-99 m NeoTect. Similarly, spherical phantoms of 1.0-cm diameter were generated to model small SPN for each of the 150 uniquely located sites within the lungs whose respiratory motion was based on the motion of normal structures in the volunteer CT studies. The SIMIND Monte Carlo program was used to produce SPECT projection data from these. Normal and single-lesion containing SPECT projection sets with a clinically realistic Poisson noise level were created for the cases of 1) the end-expiration (EE) frame with all counts, 2) respiration-averaged motion with all counts, 3) one fourth of the 32 frames centered around EE (Quarter Binning), 4) one half of the 32 frames centered around EE (Half Binning), and 5) eight temporally binned frames spanning the respiratory cycle. Each of the sets of combined projection data were reconstructed with RBI-EM with system spatial-resolution compensation (RC). Based on the known motion for each of the 150 different lesions, the reconstructed volumes of respiratory bins were shifted so as to superimpose the locations of the SPN onto that in the first bin (Reconstruct and Shift). Five human observers performed localization receiver operating characteristics (LROC) studies of SPN detection. The observer results were analyzed for statistical significance differences in SPN detection accuracy among the three correction strategies, the standard acquisition, and the ideal case of the absence of respiratory motion. Our human-observer LROC determined that Quarter Binning and Half Binning strategies resulted in SPN detection accuracy statistically significantly below ( ) that of standard clinical acquisition, whereas the Reconstruct and Shift strategy resulted in a detection accuracy not statistically significantly different from that of the ideal case. This investigation demonstrates that tumor detection based on acquisitions associated with less than all the counts which could potentially be employed may result in poorer detection despite limiting the motion of the lesion. The Reconstruct and Shift method results in tumor detection that is equivalent to ideal motion correction.

Sitting in the Pilot's Seat; Optimizing Human-Systems Interfaces for Unmanned Aerial Vehicles

NASA Technical Reports Server (NTRS)

Queen, Steven M.; Sanner, Kurt Gregory

2011-01-01

One of the pilot-machine interfaces (the forward viewing camera display) for an Unmanned Aerial Vehicle called the DROID (Dryden Remotely Operated Integrated Drone) will be analyzed for optimization. The goal is to create a visual display for the pilot that as closely resembles an out-the-window view as possible. There are currently no standard guidelines for designing pilot-machine interfaces for UAVs. Typically, UAV camera views have a narrow field, which limits the situational awareness (SA) of the pilot. Also, at this time, pilot-UAV interfaces often use displays that have a diagonal length of around 20". Using a small display may result in a distorted and disproportional view for UAV pilots. Making use of a larger display and a camera lens with a wider field of view may minimize the occurrences of pilot error associated with the inability to see "out the window" as in a manned airplane. It is predicted that the pilot will have a less distorted view of the DROID s surroundings, quicker response times and more stable vehicle control. If the experimental results validate this concept, other UAV pilot-machine interfaces will be improved with this design methodology.

Calibration of the venµs super-spectral camera

NASA Astrophysics Data System (ADS)

Topaz, Jeremy; Sprecher, Tuvia; Tinto, Francesc; Echeto, Pierre; Hagolle, Olivier

2017-11-01

A high-resolution super-spectral camera is being developed by Elbit Systems in Israel for the joint CNES- Israel Space Agency satellite, VENμS (Vegetation and Environment monitoring on a new Micro-Satellite). This camera will have 12 narrow spectral bands in the Visible/NIR region and will give images with 5.3 m resolution from an altitude of 720 km, with an orbit which allows a two-day revisit interval for a number of selected sites distributed over some two-thirds of the earth's surface. The swath width will be 27 km at this altitude. To ensure the high radiometric and geometric accuracy needed to fully exploit such multiple data sampling, careful attention is given in the design to maximize characteristics such as signal-to-noise ratio (SNR), spectral band accuracy, stray light rejection, inter- band pixel-to-pixel registration, etc. For the same reasons, accurate calibration of all the principle characteristics is essential, and this presents some major challenges. The methods planned to achieve the required level of calibration are presented following a brief description of the system design. A fuller description of the system design is given in [2], [3] and [4].

A Dark Bend

NASA Image and Video Library

2016-09-05

Saturn's rings appear to bend as they pass behind the planet's darkened limb due to refraction by Saturn's upper atmosphere. The effect is the same as that seen in an earlier Cassini view (see PIA20491), except this view looks toward the unlit face of the rings, while the earlier image viewed the rings' sunlit side. The difference in illumination brings out some noticeable differences. The A ring is much darker here, on the rings' unlit face, since its larger particles primarily reflect light back toward the sun (and away from Cassini's cameras in this view). The narrow F ring (at bottom), which was faint in the earlier image, appears brighter than all of the other rings here, thanks to the microscopic dust that is prevalent within that ring. Small dust tends to scatter light forward (meaning close to its original direction of travel), making it appear bright when backlit. (A similar effect has plagued many a driver with a dusty windshield when driving toward the sun.) This view looks toward the unilluminated side of the rings from about 19 degrees below the ring plane. The image was taken in red light with the Cassini spacecraft narrow-angle camera on July 24, 2016. The view was acquired at a distance of approximately 527,000 miles (848,000 kilometers) from Saturn and at a sun-Saturn-spacecraft, or phase, angle of 169 degrees. Image scale is 3 miles (5 kilometers) per pixel. http://photojournal.jpl.nasa.gov/catalog/PIA20497

LED-based endoscopic light source for spectral imaging

NASA Astrophysics Data System (ADS)

Browning, Craig M.; Mayes, Samuel; Favreau, Peter; Rich, Thomas C.; Leavesley, Silas J.

2016-03-01

Colorectal cancer is the United States 3rd leading cancer in death rates.1 The current screening for colorectal cancer is an endoscopic procedure using white light endoscopy (WLE). There are multiple new methods testing to replace WLE, for example narrow band imaging and autofluorescence imaging.2 However, these methods do not meet the need for a higher specificity or sensitivity. The goal for this project is to modify the presently used endoscope light source to house 16 narrow wavelength LEDs for spectral imaging in real time while increasing sensitivity and specificity. The process to do such was to take an Olympus CLK-4 light source, replace the light and electronics with 16 LEDs and new circuitry. This allows control of the power and intensity of the LEDs. This required a larger enclosure to house a bracket system for the solid light guide (lightpipe), three new circuit boards, a power source and National Instruments hardware/software for computer control. The results were a successfully designed retrofit with all the new features. The LED testing resulted in the ability to control each wavelength's intensity. The measured intensity over the voltage range will provide the information needed to couple the camera for imaging. Overall the project was successful; the modifications to the light source added the controllable LEDs. This brings the research one step closer to the main goal of spectral imaging for early detection of colorectal cancer. Future goals will be to connect the camera and test the imaging process.

Background correction in forensic photography. I. Photography of blood under conditions of non-uniform illumination or variable substrate color--theoretical aspects and proof of concept.

PubMed

Wagner, John H; Miskelly, Gordon M

2003-05-01

The combination of photographs taken at two or three wavelengths at and bracketing an absorbance peak indicative of a particular compound can lead to an image with enhanced visualization of the compound. This procedure works best for compounds with absorbance bands that are narrow compared with "average" chromophores. If necessary, the photographs can be taken with different exposure times to ensure that sufficient light from the substrate is detected at all three wavelengths. The combination of images is readily performed if the images are obtained with a digital camera and are then processed using an image processing program. Best results are obtained if linear images at the peak maximum, at a slightly shorter wavelength, and at a slightly longer wavelength are used. However, acceptable results can also be obtained under many conditions if non-linear photographs are used or if only two wavelengths (one of which is at the peak maximum) are combined. These latter conditions are more achievable by many "mid-range" digital cameras. Wavelength selection can either be by controlling the illumination (e.g., by using an alternate light source) or by use of narrow bandpass filters. The technique is illustrated using blood as the target analyte, using bands of light centered at 395, 415, and 435 nm. The extension of the method to detection of blood by fluorescence quenching is also described.

Science-Filters Study of Martian Rock Sees Hematite

NASA Image and Video Library

2017-11-01

This false-color image demonstrates how use of special filters available on the Mast Camera (Mastcam) of NASA's Curiosity Mars rover can reveal the presence of certain minerals in target rocks. It is a composite of images taken through three "science" filters chosen for making hematite, an iron-oxide mineral, stand out as exaggerated purple. This target rock, called "Christmas Cove," lies in an area on Mars' "Vera Rubin Ridge" where Mastcam reconnaissance imaging (see PIA22065) with science filters suggested a patchy distribution of exposed hematite. Bright lines within the rocks are fractures filled with calcium sulfate minerals. Christmas Cove did not appear to contain much hematite until the rover team conducted an experiment on this target: Curiosity's wire-bristled brush, the Dust Removal Tool, scrubbed the rock, and a close-up with the Mars Hand Lens Imager (MAHLI) confirmed the brushing. The brushed area is about is about 2.5 inches (6 centimeters) across. The next day -- Sept. 17, 2017, on the mission's Sol 1819 -- this observation with Mastcam and others with the Chemistry and Camera (ChemCam showed a strong hematite presence that had been subdued beneath the dust. The team is continuing to explore whether the patchiness in the reconnaissance imaging may result more from variations in the amount of dust cover rather than from variations in hematite content. Curiosity's Mastcam combines two cameras: one with a telephoto lens and the other with a wider-angle lens. Each camera has a filter wheel that can be rotated in front of the lens for a choice of eight different filters. One filter for each camera is clear to all visible light, for regular full-color photos, and another is specifically for viewing the Sun. Some of the other filters were selected to admit wavelengths of light that are useful for identifying iron minerals. Each of the filters used for this image admits light from a narrow band of wavelengths, extending to only about 5 nanometers longer or shorter than the filter's central wavelength. Three observations are combined for this image, each through one of the filters centered at 751 nanometers (in the near-infrared part of the spectrum just beyond red light), 527 nanometers (green) and 445 nanometers (blue). Usual color photographs from digital cameras -- such as a Mastcam one of this same place (see PIA22067) -- also combine information from red, green and blue filtering, but the filters are in a microscopic grid in a "Bayer" filter array situated directly over the detector behind the lens, with wider bands of wavelengths. Mastcam's narrow-band filters used for this view help to increase spectral contrast, making blues bluer and reds redder, particularly with the processing used to boost contrast in each of the component images of this composite. Fine-grained hematite preferentially absorbs sunlight around in the green portion of the spectrum around 527 nanometers. That gives it the purple look from a combination of red and blue light reflected by the hematite and reaching the camera through the other two filters. https://photojournal.jpl.nasa.gov/catalog/PIA22066

Shallow Lunar Seismic Activity and the Current Stress State of the Moon

NASA Technical Reports Server (NTRS)

Watters, Thomas R.; Weber, Renee C.; Collins, Geoffrey C.; Johnson, Catherine L.

2017-01-01

A vast, global network of more than 3200 lobate thrust fault scarps has been revealed in high resolution Lunar Reconnaissance Orbiter Camera (LROC) images. The fault scarps are very young, less than 50 Ma, based on their small scale and crisp appearance, crosscutting relations with small-diameter impact craters, and rates of infilling of associated small, shallow graben and may be actively forming today. The population of young thrust fault scarps provides a window into the recent stress state of the Moon and offers insight into the origin of global lunar stresses. The distribution of orientations of the fault scarps is non-random, inconsistent with isotropic stresses from late-stage global contraction as the sole source of stress. Modeling shows that tidal stresses contribute significantly to the current stress state of the lunar crust. Tidal stresses (orbital recession and diurnal tides) superimposed on stresses from global contraction result in non-isotropic compressional stress and may produce thrust faults consistent with lobate scarp orientations. At any particular point on the lunar surface, peak compressive stress will be reached at a certain time in the diurnal cycle. Coseismic slip events on currently active thrust faults are expected to be triggered when peak stresses are reached. Analysis of the timing of the 28 the shallow moonquakes recorded by the Apollo seismic network shows that 19 indeed occur when the Moon is closer to apogee, while only 9 shallow events occur when the Moon is closer to perigee. Here we report efforts to refine the model for the current stress state of the Moon by investigating the contribution of polar wander. Progress on relocating the epicentral locations of the shallow moonquakes using an algorithm designed for sparse networks is also reported.

A high resolution IR/visible imaging system for the W7-X limiter

NASA Astrophysics Data System (ADS)

Wurden, G. A.; Stephey, L. A.; Biedermann, C.; Jakubowski, M. W.; Dunn, J. P.; Gamradt, M.

2016-11-01

A high-resolution imaging system, consisting of megapixel mid-IR and visible cameras along the same line of sight, has been prepared for the new W7-X stellarator and was operated during Operational Period 1.1 to view one of the five inboard graphite limiters. The radial line of sight, through a large diameter (184 mm clear aperture) uncoated sapphire window, couples a direct viewing 1344 × 784 pixel FLIR SC8303HD camera. A germanium beam-splitter sends visible light to a 1024 × 1024 pixel Allied Vision Technologies Prosilica GX1050 color camera. Both achieve sub-millimeter resolution on the 161 mm wide, inertially cooled, segmented graphite tiles. The IR and visible cameras are controlled via optical fibers over full Camera Link and dual GigE Ethernet (2 Gbit/s data rates) interfaces, respectively. While they are mounted outside the cryostat at a distance of 3.2 m from the limiter, they are close to a large magnetic trim coil and require soft iron shielding. We have taken IR data at 125 Hz to 1.25 kHz frame rates and seen that surface temperature increases in excess of 350 °C, especially on leading edges or defect hot spots. The IR camera sees heat-load stripe patterns on the limiter and has been used to infer limiter power fluxes (˜1-4.5 MW/m2), during the ECRH heating phase. IR images have also been used calorimetrically between shots to measure equilibrated bulk tile temperature, and hence tile energy inputs (in the range of 30 kJ/tile with 0.6 MW, 6 s heating pulses). Small UFO's can be seen and tracked by the FLIR camera in some discharges. The calibrated visible color camera (100 Hz frame rate) has also been equipped with narrow band C-III and H-alpha filters, to compare with other diagnostics, and is used for absolute particle flux determination from the limiter surface. Sometimes, but not always, hot-spots in the IR are also seen to be bright in C-III light.

A high resolution IR/visible imaging system for the W7-X limiter

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wurden, G. A., E-mail: wurden@lanl.gov; Dunn, J. P.; Stephey, L. A.

A high-resolution imaging system, consisting of megapixel mid-IR and visible cameras along the same line of sight, has been prepared for the new W7-X stellarator and was operated during Operational Period 1.1 to view one of the five inboard graphite limiters. The radial line of sight, through a large diameter (184 mm clear aperture) uncoated sapphire window, couples a direct viewing 1344 × 784 pixel FLIR SC8303HD camera. A germanium beam-splitter sends visible light to a 1024 × 1024 pixel Allied Vision Technologies Prosilica GX1050 color camera. Both achieve sub-millimeter resolution on the 161 mm wide, inertially cooled, segmented graphitemore » tiles. The IR and visible cameras are controlled via optical fibers over full Camera Link and dual GigE Ethernet (2 Gbit/s data rates) interfaces, respectively. While they are mounted outside the cryostat at a distance of 3.2 m from the limiter, they are close to a large magnetic trim coil and require soft iron shielding. We have taken IR data at 125 Hz to 1.25 kHz frame rates and seen that surface temperature increases in excess of 350 °C, especially on leading edges or defect hot spots. The IR camera sees heat-load stripe patterns on the limiter and has been used to infer limiter power fluxes (∼1–4.5 MW/m{sup 2}), during the ECRH heating phase. IR images have also been used calorimetrically between shots to measure equilibrated bulk tile temperature, and hence tile energy inputs (in the range of 30 kJ/tile with 0.6 MW, 6 s heating pulses). Small UFO’s can be seen and tracked by the FLIR camera in some discharges. The calibrated visible color camera (100 Hz frame rate) has also been equipped with narrow band C-III and H-alpha filters, to compare with other diagnostics, and is used for absolute particle flux determination from the limiter surface. Sometimes, but not always, hot-spots in the IR are also seen to be bright in C-III light.« less

Lunar Cartography: Progress in the 2000S and Prospects for the 2010S

NASA Astrophysics Data System (ADS)

Kirk, R. L.; Archinal, B. A.; Gaddis, L. R.; Rosiek, M. R.

2012-08-01

The first decade of the 21st century has seen a new golden age of lunar exploration, with more missions than in any decade since the 1960's and many more nations participating than at any time in the past. We have previously summarized the history of lunar mapping and described the lunar missions planned for the 2000's (Kirk et al., 2006, 2007, 2008). Here we report on the outcome of lunar missions of this decade, the data gathered, the cartographic work accomplished and what remains to be done, and what is known about mission plans for the coming decade. Four missions of lunar orbital reconnaissance were launched and completed in the decade 2001-2010: SMART-1 (European Space Agency), SELENE/Kaguya (Japan), Chang'e-1 (China), and Chandrayaan-1 (India). In addition, the Lunar Reconnaissance Orbiter or LRO (USA) is in an extended mission, and Chang'e-2 (China) operated in lunar orbit in 2010-2011. All these spacecraft have incorporated cameras capable of providing basic data for lunar mapping, and all but SMART-1 carried laser altimeters. Chang'e-1, Chang'e-2, Kaguya, and Chandrayaan-1 carried pushbroom stereo cameras intended for stereo mapping at scales of 120, 10, 10, and 5 m/pixel respectively, and LRO is obtaining global stereo imaging at 100 m/pixel with its Wide Angle Camera (WAC) and hundreds of targeted stereo observations at 0.5 m/pixel with its Narrow Angle Camera (NAC). Chandrayaan-1 and LRO carried polarimetric synthetic aperture radars capable of 75 m/pixel and (LRO only) 7.5 m/pixel imaging even in shadowed areas, and most missions carried spectrometers and imaging spectrometers whose lower resolution data are urgently in need of coregistration with other datasets and correction for topographic and illumination effects. The volume of data obtained is staggering. As one example, the LRO laser altimeter, LOLA, has so far made more than 5.5 billion elevation measurements, and the LRO Camera (LROC) system has returned more than 1.3 million archived image products comprising over 220 Terabytes of image data. The processing of controlled map products from these data is as yet relatively limited. A substantial portion of the LOLA altimetry data have been subjected to a global crossover analysis, and local crossover analyses of Chang'e-1 LAM altimetry have also been performed. LRO NAC stereo digital topographic models (DTMs) and orthomosaics of numerous sites of interest have been prepared based on control to LOLA data, and production of controlled mosaics and DTMs from Mini-RF radar images has begun. Many useful datasets (e.g., DTMs from LRO WAC images and Kaguya Terrain Camera images) are currently uncontrolled. Making controlled, orthorectified map products is obviously a high priority for lunar cartography, and scientific use of the vast multinational set of lunar data now available will be most productive if all observations can be integrated into a single reference frame. To achieve this goal, the key steps required are (a) joint registration and reconciliation of the laser altimeter data from multiple missions, in order to provide the best current reference frame for other products; (b) registration of image datasets (including spectral images and radar, as well as monoscopic and stereo optical images) to one another and the topographic surface from altimetry by bundle adjustment; (c) derivation of higher density topographic models than the altimetry provides, based on the stereo images registered to the altimetric data; and (d) orthorectification and mosaicking of the various datasets based on the dense and consistent topographic model resulting from the previous steps. In the final step, the dense and consistent topographic data will be especially useful for correcting spectrophotometric observations to facilitate mapping of geologic and mineralogic features. We emphasize that, as desirable as short term progress may seem, making mosaics before controlling observations, and controlling observations before a single coordinate reference frame is agreed upon by all participants, are counterproductive and will result in a collection of map products that do not align with one another and thus will not be fully usable for correlative scientific studies. Only a few lunar orbital missions performing remote sensing are projected for the decade 2011-2020. These include the possible further extension of the LRO mission; NASA's GRAIL mission, which is making precise measurements of the lunar gravity field that will likely improve the cartographic accuracy of data from other missions, and the Chandrayaan-2/Luna Resurs mission planned by India and Russia, which includes an orbital remote sensing component. A larger number of surface missions are being discussed for the current decade, including the lander/rover component of Chandrayaan-2/Luna Resurs, Chang'e-3 (China), SELENE-2 (Japan), and privately funded missions inspired by the Google Lunar X-Prize. The US Lunar Precursor Robotic Program was discontinued in 2010, leaving NASA with no immediate plans for robotic or human exploration of the lunar surface, though the MoonRise sample return mission might be reproposed in the future. If the cadence of missions cannot be continued, the desired sequel to the decade of lunar mapping missions 2001-2010 should be a decade of detailed and increasingly multinational analysis of lunar data from 2011 onward.

KSC-2009-3298

NASA Image and Video Library

2009-05-28

CAPE CANAVERAL, Fla. – On Launch Complex 41 at Cape Canaveral Air Force Station in Florida, the Lunar Reconnaissance Orbiter, or LRO, and NASA's Lunar Crater Observation and Sensing Satellite, known as LCROSS, are lifted into the mobile service tower. The LRO/LCROSS will be mated to the Atlas V rocket for launch. The LRO includes five instruments that will help NASA characterize the moon's surface: DIVINER, LAMP, LEND, LOLA and LROC. Along with LCROSS, they will be launched aboard an Atlas V/Centaur rocket on June 17. Photo credit: NASA/Dimitri Gerondidakis

KSC-2009-3297

NASA Image and Video Library

2009-05-28

CAPE CANAVERAL, Fla. – On Launch Complex 41 at Cape Canaveral Air Force Station in Florida, a crane is attached to the Lunar Reconnaissance Orbiter, or LRO, and NASA's Lunar Crater Observation and Sensing Satellite, known as LCROSS, to lift them into the mobile service tower. The LRO/LCROSS will be mated to the Atlas V rocket for launch. The LRO includes five instruments that will help NASA characterize the moon's surface: DIVINER, LAMP, LEND, LOLA and LROC. Along with LCROSS, they will be launched aboard an Atlas V/Centaur rocket on June 17. Photo credit: NASA/Dimitri Gerondidakis

KSC-2009-3762

NASA Image and Video Library

2009-06-18

CAPE CANAVERAL, Fla. – NASA's Lunar Reconnaissance Orbiter, or LRO, and NASA's Lunar Crater Observation and Sensing Satellite, known as LCROSS, lifts off from Launch Pad 41 at Cape Canaveral Air Force Station in Florida. LRO and LCROSS are the first missions in NASA's plan to return humans to the moon and begin establishing a lunar outpost by 2020. The LRO also includes seven instruments that will help NASA characterize the moon's surface: DIVINER, LAMP, LEND, LOLA , CRATER, Mini-RF and LROC. Launch was on-time at 5:32 p.m. EDT June 18. Photo credit: NASA/Sandra Joseph

A Summary of the Evaluation of PPG Herculite XP Glass in Punched Window and Storefront Assemblies

DTIC Science & Technology

2013-01-01

frames for all IGU windows extruded from existing dies. The glazing was secured to the frame on all four sides with a 1/2-in bead width of DOW 995...lite and non-laminated IGU debris tests. A wood frame with a 4-in wide slit was placed behind the window to transform the debris cloud into a narrow...speed camera DIC Set-up laser deflection gauge shock tube window wood frame with slit high speed camerawell lit backdrop Debris Tracking Set-up laser

Extracting spatial information from large aperture exposures of diffuse sources

NASA Technical Reports Server (NTRS)

Clarke, J. T.; Moos, H. W.

1981-01-01

The spatial properties of large aperture exposures of diffuse emission can be used both to investigate spatial variations in the emission and to filter out camera noise in exposures of weak emission sources. Spatial imaging can be accomplished both parallel and perpendicular to dispersion with a resolution of 5-6 arc sec, and a narrow median filter running perpendicular to dispersion across a diffuse image selectively filters out point source features, such as reseaux marks and fast particle hits. Spatial information derived from observations of solar system objects is presented.

Contrasting Crescents

NASA Image and Video Library

2018-02-05

In this view, Saturn's icy moon Rhea passes in front of Titan as seen by NASA's Cassini spacecraft. Some of the differences between the two large moons are readily apparent. While Rhea is a heavily-cratered, airless world, Titan's nitrogen-rich atmosphere is even thicker than Earth's. This natural color image was taken in visible light with the Cassini narrow-angle camera on Nov. 19, 2009, at a distance of approximately 713,300 miles (1,148,000 kilometers) from Rhea. The Cassini spacecraft ended its mission on Sept. 15, 2017. https://photojournal.jpl.nasa.gov/catalog/PIA21904

Mechanism controller system for the optical spectroscopic and infrared remote imaging system instrument on board the Rosetta space mission

NASA Astrophysics Data System (ADS)

Castro Marín, J. M.; Brown, V. J. G.; López Jiménez, A. C.; Rodríguez Gómez, J.; Rodrigo, R.

2001-05-01

The optical, spectroscopic infrared remote imaging system (OSIRIS) is an instrument carried on board the European Space Agency spacecraft Rosetta that will be launched in January 2003 to study in situ the comet Wirtanen. The electronic design of the mechanism controller board (MCB) system of the two OSIRIS optical cameras, the narrow angle camera, and the wide angle camera, is described here. The system is comprised of two boards mounted on an aluminum frame as part of an electronics box that contains the power supply and the digital processor unit of the instrument. The mechanisms controlled by the MCB for each camera are the front door assembly and a filter wheel assembly. The front door assembly for each camera is driven by a four phase, permanent magnet stepper motor. Each filter wheel assembly consists of two, eight filter wheels. Each wheel is driven by a four phase, variable reluctance stepper motor. Each motor, for all the assemblies, also contains a redundant set of four stator phase windings that can be energized separately or in parallel with the main windings. All stepper motors are driven in both directions using the full step unipolar mode of operation. The MCB also performs general housekeeping data acquisition of the OSIRIS instrument, i.e., mechanism position encoders and temperature measurements. The electronic design application used is quite new due to use of a field programmable gate array electronic devices that avoid the use of the now traditional system controlled by microcontrollers and software. Electrical tests of the engineering model have been performed successfully and the system is ready for space qualification after environmental testing. This system may be of interest to institutions involved in future space experiments with similar needs for mechanisms control.

Cassini Camera Contamination Anomaly: Experiences and Lessons Learned

NASA Technical Reports Server (NTRS)

Haemmerle, Vance R.; Gerhard, James H.

2006-01-01

We discuss the contamination 'Haze' anomaly for the Cassini Narrow Angle Camera (NAC), one of two optical telescopes that comprise the Imaging Science Subsystem (ISS). Cassini is a Saturn Orbiter with a 4-year nominal mission. The incident occurred in 2001, five months after Jupiter encounter during the Cruise phase and ironically at the resumption of planned maintenance decontamination cycles. The degraded optical performance was first identified by the Instrument Operations Team with the first ISS Saturn imaging six weeks later. A distinct haze of varying size from image to image marred the images of Saturn. A photometric star calibration of the Pleiades, 4 days after the incident, showed stars with halos. Analysis showed that while the halo's intensity was only 1 - 2% of the intensity of the central peak of a star, the halo contained 30 - 70% of its integrated flux. This condition would impact science return. In a review of our experiences, we examine the contamination control plan, discuss the analysis of the limited data available and describe the one-year campaign to remove the haze from the camera. After several long conservative heating activities and interim analysis of their results, the contamination problem as measured by the camera's point spread function was essentially back to preanomaly size and at a point where there would be more risk to continue. We stress the importance of the flexibility of operations and instrument design, the need to do early infight instrument calibration and continual monitoring of instrument performance.

Temporal Imaging CeBr3 Compton Camera: A New Concept for Nuclear Decommissioning and Nuclear Waste Management

NASA Astrophysics Data System (ADS)

Iltis, A.; Snoussi, H.; Magalhaes, L. Rodrigues de; Hmissi, M. Z.; Zafiarifety, C. Tata; Tadonkeng, G. Zeufack; Morel, C.

2018-01-01

During nuclear decommissioning or waste management operations, a camera that could make an image of the contamination field and identify and quantify the contaminants would be a great progress. Compton cameras have been proposed, but their limited efficiency for high energy gamma rays and their cost have severely limited their application. Our objective is to promote a Compton camera for the energy range (200 keV - 2 MeV) that uses fast scintillating crystals and a new concept for locating scintillation event: Temporal Imaging. Temporal Imaging uses monolithic plates of fast scintillators and measures photons time of arrival distribution in order to locate each gamma ray with a high precision in space (X,Y,Z), time (T) and energy (E). This provides a native estimation of the depth of interaction (Z) of every detected gamma ray. This also allows a time correction for the propagation time of scintillation photons inside the crystal, therefore resulting in excellent time resolution. The high temporal resolution of the system makes it possible to veto quite efficiently background by using narrow time coincidence (< 300 ps). It is also possible to reconstruct the direction of propagation of the photons inside the detector using timing constraints. The sensitivity of our system is better than 1 nSv/h in a 60 s acquisition with a 22Na source. The project TEMPORAL is funded by the ANDRA/PAI under the grant No. RTSCNADAA160019.

Pre-hibernation performances of the OSIRIS cameras onboard the Rosetta spacecraft

NASA Astrophysics Data System (ADS)

Magrin, S.; La Forgia, F.; Da Deppo, V.; Lazzarin, M.; Bertini, I.; Ferri, F.; Pajola, M.; Barbieri, M.; Naletto, G.; Barbieri, C.; Tubiana, C.; Küppers, M.; Fornasier, S.; Jorda, L.; Sierks, H.

2015-02-01

Context. The ESA cometary mission Rosetta was launched in 2004. In the past years and until the spacecraft hibernation in June 2011, the two cameras of the OSIRIS imaging system (Narrow Angle and Wide Angle Camera, NAC and WAC) observed many different sources. On 20 January 2014 the spacecraft successfully exited hibernation to start observing the primary scientific target of the mission, comet 67P/Churyumov-Gerasimenko. Aims: A study of the past performances of the cameras is now mandatory to be able to determine whether the system has been stable through the time and to derive, if necessary, additional analysis methods for the future precise calibration of the cometary data. Methods: The instrumental responses and filter passbands were used to estimate the efficiency of the system. A comparison with acquired images of specific calibration stars was made, and a refined photometric calibration was computed, both for the absolute flux and for the reflectivity of small bodies of the solar system. Results: We found a stability of the instrumental performances within ±1.5% from 2007 to 2010, with no evidence of an aging effect on the optics or detectors. The efficiency of the instrumentation is found to be as expected in the visible range, but lower than expected in the UV and IR range. A photometric calibration implementation was discussed for the two cameras. Conclusions: The calibration derived from pre-hibernation phases of the mission will be checked as soon as possible after the awakening of OSIRIS and will be continuously monitored until the end of the mission in December 2015. A list of additional calibration sources has been determined that are to be observed during the forthcoming phases of the mission to ensure a better coverage across the wavelength range of the cameras and to study the possible dust contamination of the optics.

Olympus Mons in Color

NASA Technical Reports Server (NTRS)

1997-01-01

Sections of MOC images P024_01 and P024_02, shown here in color composite form, were acquired with the low resolution red and blue wide angle cameras over a 5 minute period starting when Mars Global Surveyor was at its closest point to the planet at the beginning of its 24th orbit (around 4:00 AM PDT on October 20, 1997). To make this image, a third component (green) was synthesized from the red and blue images. During the imaging period, the camera was pointed straight down towards the martian surface, 176 km (109 miles) below the spacecraft. During the time it took to acquire the image, the spacecraft rose to an altitude of 310 km (193 miles). Owing to data camera scanning rate and data volume constraints, the image was acquired at a resolution of roughly 1 km (0.609 mile) per pixel. The image shown here covers an area from 12o to 26o N latitude and 126o N to 138o W longitude. The image is oriented with north to the top.

As has been noted in other MOC releases, Olympus Mons is the largest of the major Tharsis volcanoes, rising 25 km (15.5 miles) and stretching over nearly 550 km (340 miles) east-west. The summit caldera, a composite of as many as seven roughly circular collapse depressions, is 66 by 83 km (41 by 52 miles) across. Also seen in this image are water-ice clouds that accumulate around and above the volcano during the late afternoon (at the time the image was acquired, the summit was at 5:30 PM local solar time). To understand the value of orbital observations, compare this image with the two taken during approach (PIA00929 and PIA00936), that are representative of the best resolution from Earth.

Through Monday, October 28, the MOC had acquired a total of 132 images, most of which were at low sun elevation angles. Of these images, 74 were taken with the high resolution narrow angle camera and 58 with the low resolution wide angle cameras. Twenty-eight narrow angle and 24 wide angle images were taken after the suspension of aerobraking. These images, including the one shown above, are among the best returned so far.

Launched on November 7, 1996, Mars Global Surveyor entered Mars orbit on Thursday, September 11, 1997. The original mission plan called for using friction with the planet's atmosphere to reduce the orbital energy, leading to a two-year mapping mission from close, circular orbit (beginning in March 1998). Owing to difficulties with one of the two solar panels, aerobraking was suspended in mid-October and is scheduled to resume in mid-November. Many of the original objectives of the mission, and in particular those of the camera, are likely to be accomplished as the mission progresses.

Malin Space Science Systems and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO.

Remote sensing and implications for variable-rate application using agricultural aircraft

NASA Astrophysics Data System (ADS)

Thomson, Steven J.; Smith, Lowrey A.; Ray, Jeffrey D.; Zimba, Paul V.

2004-01-01

Aircraft routinely used for agricultural spray application are finding utility for remote sensing. Data obtained from remote sensing can be used for prescription application of pesticides, fertilizers, cotton growth regulators, and water (the latter with the assistance of hyperspectral indices and thermal imaging). Digital video was used to detect weeds in early cotton, and preliminary data were obtained to see if nitrogen status could be detected in early soybeans. Weeds were differentiable from early cotton at very low altitudes (65-m), with the aid of supervised classification algorithms in the ENVI image analysis software. The camera was flown at very low altitude for acceptable pixel resolution. Nitrogen status was not detectable by statistical analysis of digital numbers (DNs) obtained from images, but soybean cultivar differences were statistically discernable (F=26, p=0.01). Spectroradiometer data are being analyzed to identify narrow spectral bands that might aid in selecting camera filters for determination of plant nitrogen status. Multiple camera configurations are proposed to allow vegetative indices to be developed more readily. Both remotely sensed field images and ground data are to be used for decision-making in a proposed variable-rate application system for agricultural aircraft. For this system, prescriptions generated from digital imagery and data will be coupled with GPS-based swath guidance and programmable flow control.

Label-free biodetection using a smartphone.

PubMed

Gallegos, Dustin; Long, Kenneth D; Yu, Hojeong; Clark, Peter P; Lin, Yixiao; George, Sherine; Nath, Pabitra; Cunningham, Brian T

2013-06-07

Utilizing its integrated camera as a spectrometer, we demonstrate the use of a smartphone as the detection instrument for a label-free photonic crystal biosensor. A custom-designed cradle holds the smartphone in fixed alignment with optical components, allowing for accurate and repeatable measurements of shifts in the resonant wavelength of the sensor. Externally provided broadband light incident upon an entrance pinhole is subsequently collimated and linearly polarized before passing through the biosensor, which resonantly reflects only a narrow band of wavelengths. A diffraction grating spreads the remaining wavelengths over the camera's pixels to display a high resolution transmission spectrum. The photonic crystal biosensor is fabricated on a plastic substrate and attached to a standard glass microscope slide that can easily be removed and replaced within the optical path. A custom software app was developed to convert the camera images into the photonic crystal transmission spectrum in the visible wavelength range, including curve-fitting analysis that computes the photonic crystal resonant wavelength with 0.009 nm accuracy. We demonstrate the functionality of the system through detection of an immobilized protein monolayer, and selective detection of concentration-dependent antibody binding to a functionalized photonic crystal. We envision the capability for an inexpensive, handheld biosensor instrument with web connectivity to enable point-of-care sensing in environments that have not been practical previously.

Immersive viewing engine

NASA Astrophysics Data System (ADS)

Schonlau, William J.

2006-05-01

An immersive viewing engine providing basic telepresence functionality for a variety of application types is presented. Augmented reality, teleoperation and virtual reality applications all benefit from the use of head mounted display devices that present imagery appropriate to the user's head orientation at full frame rates. Our primary application is the viewing of remote environments, as with a camera equipped teleoperated vehicle. The conventional approach where imagery from a narrow field camera onboard the vehicle is presented to the user on a small rectangular screen is contrasted with an immersive viewing system where a cylindrical or spherical format image is received from a panoramic camera on the vehicle, resampled in response to sensed user head orientation and presented via wide field eyewear display, approaching 180 degrees of horizontal field. Of primary interest is the user's enhanced ability to perceive and understand image content, even when image resolution parameters are poor, due to the innate visual integration and 3-D model generation capabilities of the human visual system. A mathematical model for tracking user head position and resampling the panoramic image to attain distortion free viewing of the region appropriate to the user's current head pose is presented and consideration is given to providing the user with stereo viewing generated from depth map information derived using stereo from motion algorithms.

Autonomous Aerial Refueling Ground Test Demonstration—A Sensor-in-the-Loop, Non-Tracking Method

PubMed Central

Chen, Chao-I; Koseluk, Robert; Buchanan, Chase; Duerner, Andrew; Jeppesen, Brian; Laux, Hunter

2015-01-01

An essential capability for an unmanned aerial vehicle (UAV) to extend its airborne duration without increasing the size of the aircraft is called the autonomous aerial refueling (AAR). This paper proposes a sensor-in-the-loop, non-tracking method for probe-and-drogue style autonomous aerial refueling tasks by combining sensitivity adjustments of a 3D Flash LIDAR camera with computer vision based image-processing techniques. The method overcomes the inherit ambiguity issues when reconstructing 3D information from traditional 2D images by taking advantage of ready to use 3D point cloud data from the camera, followed by well-established computer vision techniques. These techniques include curve fitting algorithms and outlier removal with the random sample consensus (RANSAC) algorithm to reliably estimate the drogue center in 3D space, as well as to establish the relative position between the probe and the drogue. To demonstrate the feasibility of the proposed method on a real system, a ground navigation robot was designed and fabricated. Results presented in the paper show that using images acquired from a 3D Flash LIDAR camera as real time visual feedback, the ground robot is able to track a moving simulated drogue and continuously narrow the gap between the robot and the target autonomously. PMID:25970254

Compact Hyperspectral Imaging System (cosi) for Small Remotely Piloted Aircraft Systems (rpas) - System Overview and First Performance Evaluation Results

NASA Astrophysics Data System (ADS)

Sima, A. A.; Baeck, P.; Nuyts, D.; Delalieux, S.; Livens, S.; Blommaert, J.; Delauré, B.; Boonen, M.

2016-06-01

This paper gives an overview of the new COmpact hyperSpectral Imaging (COSI) system recently developed at the Flemish Institute for Technological Research (VITO, Belgium) and suitable for remotely piloted aircraft systems. A hyperspectral dataset captured from a multirotor platform over a strawberry field is presented and explored in order to assess spectral bands co-registration quality. Thanks to application of line based interference filters deposited directly on the detector wafer the COSI camera is compact and lightweight (total mass of 500g), and captures 72 narrow (FWHM: 5nm to 10 nm) bands in the spectral range of 600-900 nm. Covering the region of red edge (680 nm to 730 nm) allows for deriving plant chlorophyll content, biomass and hydric status indicators, making the camera suitable for agriculture purposes. Additionally to the orthorectified hypercube digital terrain model can be derived enabling various analyses requiring object height, e.g. plant height in vegetation growth monitoring. Geometric data quality assessment proves that the COSI camera and the dedicated data processing chain are capable to deliver very high resolution data (centimetre level) where spectral information can be correctly derived. Obtained results are comparable or better than results reported in similar studies for an alternative system based on the Fabry-Pérot interferometer.

Photogrammetric Processing of Planetary Linear Pushbroom Images Based on Approximate Orthophotos

NASA Astrophysics Data System (ADS)

Geng, X.; Xu, Q.; Xing, S.; Hou, Y. F.; Lan, C. Z.; Zhang, J. J.

2018-04-01

It is still a great challenging task to efficiently produce planetary mapping products from orbital remote sensing images. There are many disadvantages in photogrammetric processing of planetary stereo images, such as lacking ground control information and informative features. Among which, image matching is the most difficult job in planetary photogrammetry. This paper designs a photogrammetric processing framework for planetary remote sensing images based on approximate orthophotos. Both tie points extraction for bundle adjustment and dense image matching for generating digital terrain model (DTM) are performed on approximate orthophotos. Since most of planetary remote sensing images are acquired by linear scanner cameras, we mainly deal with linear pushbroom images. In order to improve the computational efficiency of orthophotos generation and coordinates transformation, a fast back-projection algorithm of linear pushbroom images is introduced. Moreover, an iteratively refined DTM and orthophotos scheme was adopted in the DTM generation process, which is helpful to reduce search space of image matching and improve matching accuracy of conjugate points. With the advantages of approximate orthophotos, the matching results of planetary remote sensing images can be greatly improved. We tested the proposed approach with Mars Express (MEX) High Resolution Stereo Camera (HRSC) and Lunar Reconnaissance Orbiter (LRO) Narrow Angle Camera (NAC) images. The preliminary experimental results demonstrate the feasibility of the proposed approach.

A Fractured Pole

NASA Image and Video Library

2015-10-15

NASA's Cassini spacecraft zoomed by Saturn's icy moon Enceladus on Oct. 14, 2015, capturing this stunning image of the moon's north pole. A companion view from the wide-angle camera (PIA20010) shows a zoomed out view of the same region for context. Scientists expected the north polar region of Enceladus to be heavily cratered, based on low-resolution images from the Voyager mission, but high-resolution Cassini images show a landscape of stark contrasts. Thin cracks cross over the pole -- the northernmost extent of a global system of such fractures. Before this Cassini flyby, scientists did not know if the fractures extended so far north on Enceladus. North on Enceladus is up. The image was taken in visible green light with the Cassini spacecraft narrow-angle camera. The view was acquired at a distance of approximately 4,000 miles (6,000 kilometers) from Enceladus and at a Sun-Enceladus-spacecraft, or phase, angle of 9 degrees. Image scale is 115 feet (35 meters) per pixel. http://photojournal.jpl.nasa.gov/catalog/PIA19660

ARC-1989-A89-7004

NASA Image and Video Library

1989-08-19

Range : 8.6 million kilometers (5.3 million miles) The Voyager took this 61 second exposure through the clear filter with the narrow angle camera of Neptune. The Voyager cameras were programmed to make a systematic search for faint ring arcs and new satellites. The bright upper corner of the image is due to a residual image from a previous long exposure of the planet. The portion of the arc visible here is approximately 35 degrees in longitudinal extent, making it approximately 38,000 kilometers (24,000 miles) in length, and is broken up into three segments separated from each other by approximately 5 degrees. The trailing edge is at the upper right and has an abrupt end while the leading edge seems to fade into the background more gradually. This arc orbits very close to one of the newly discovered Neptune satellites, 1989N4. Close-up studies of this ring arc will be carried out in the coming days which will give higher spatial resolution at different lighting angles. (JPL Ref: P-34617)

Real-time detection and data acquisition system for the left ventricular outline. Ph.D. Thesis - Stanford Univ.

NASA Technical Reports Server (NTRS)

Reiber, J. H. C.

1976-01-01

To automate the data acquisition procedure, a real-time contour detection and data acquisition system for the left ventricular outline was developed using video techniques. The X-ray image of the contrast-filled left ventricle is stored for subsequent processing on film (cineangiogram), video tape or disc. The cineangiogram is converted into video format using a television camera. The video signal from either the TV camera, video tape or disc is the input signal to the system. The contour detection is based on a dynamic thresholding technique. Since the left ventricular outline is a smooth continuous function, for each contour side a narrow expectation window is defined in which the next borderpoint will be detected. A computer interface was designed and built for the online acquisition of the coordinates using a PDP-12 computer. The advantage of this system over other available systems is its potential for online, real-time acquisition of the left ventricular size and shape during angiocardiography.

Electric Field Reconstruction in the Image Plane of a High-Contrast Coronagraph Using a Set of Pinholes around the Lyot Plane

NASA Technical Reports Server (NTRS)

Giveona, Amir; Shaklan, Stuart; Kern, Brian; Noecker, Charley; Kendrick, Steve; Wallace, Kent

2012-01-01

In a setup similar to the self coherent camera, we have added a set of pinholes in the diffraction ring of the Lyot plane in a high-contrast stellar Lyot coronagraph. We describe a novel complex electric field reconstruction from image plane intensity measurements consisting of light in the coronagraph's dark hole interfering with light from the pinholes. The image plane field is modified by letting light through one pinhole at a time. In addition to estimation of the field at the science camera, this method allows for self-calibration of the probes by letting light through the pinholes in various permutations while blocking the main Lyot opening. We present results of estimation and calibration from the High Contrast Imaging Testbed along with a comparison to the pair-wise deformable mirror diversity based estimation technique. Tests are carried out in narrow-band light and over a composite 10% bandpass.

A Precise Visual Method for Narrow Butt Detection in Specular Reflection Workpiece Welding

PubMed Central

Zeng, Jinle; Chang, Baohua; Du, Dong; Hong, Yuxiang; Chang, Shuhe; Zou, Yirong

2016-01-01

During the complex path workpiece welding, it is important to keep the welding torch aligned with the groove center using a visual seam detection method, so that the deviation between the torch and the groove can be corrected automatically. However, when detecting the narrow butt of a specular reflection workpiece, the existing methods may fail because of the extremely small groove width and the poor imaging quality. This paper proposes a novel detection method to solve these issues. We design a uniform surface light source to get high signal-to-noise ratio images against the specular reflection effect, and a double-line laser light source is used to obtain the workpiece surface equation relative to the torch. Two light sources are switched on alternately and the camera is synchronized to capture images when each light is on; then the position and pose between the torch and the groove can be obtained nearly at the same time. Experimental results show that our method can detect the groove effectively and efficiently during the welding process. The image resolution is 12.5 μm and the processing time is less than 10 ms per frame. This indicates our method can be applied to real-time narrow butt detection during high-speed welding process. PMID:27649173

A Precise Visual Method for Narrow Butt Detection in Specular Reflection Workpiece Welding.

PubMed

Zeng, Jinle; Chang, Baohua; Du, Dong; Hong, Yuxiang; Chang, Shuhe; Zou, Yirong

2016-09-13

During the complex path workpiece welding, it is important to keep the welding torch aligned with the groove center using a visual seam detection method, so that the deviation between the torch and the groove can be corrected automatically. However, when detecting the narrow butt of a specular reflection workpiece, the existing methods may fail because of the extremely small groove width and the poor imaging quality. This paper proposes a novel detection method to solve these issues. We design a uniform surface light source to get high signal-to-noise ratio images against the specular reflection effect, and a double-line laser light source is used to obtain the workpiece surface equation relative to the torch. Two light sources are switched on alternately and the camera is synchronized to capture images when each light is on; then the position and pose between the torch and the groove can be obtained nearly at the same time. Experimental results show that our method can detect the groove effectively and efficiently during the welding process. The image resolution is 12.5 μm and the processing time is less than 10 ms per frame. This indicates our method can be applied to real-time narrow butt detection during high-speed welding process.

Solar System Portrait - Earth as Pale Blue Dot

NASA Image and Video Library

1996-09-12

This narrow-angle color image of the Earth, dubbed Pale Blue Dot, is a part of the first ever 'portrait' of the solar system taken by NASA’s Voyager 1. The spacecraft acquired a total of 60 frames for a mosaic of the solar system from a distance of more than 4 billion miles from Earth and about 32 degrees above the ecliptic. From Voyager's great distance Earth is a mere point of light, less than the size of a picture element even in the narrow-angle camera. Earth was a crescent only 0.12 pixel in size. Coincidentally, Earth lies right in the center of one of the scattered light rays resulting from taking the image so close to the sun. This blown-up image of the Earth was taken through three color filters -- violet, blue and green -- and recombined to produce the color image. The background features in the image are artifacts resulting from the magnification. http://photojournal.jpl.nasa.gov/catalog/PIA00452

Light-efficient photography.

PubMed

Hasinoff, Samuel W; Kutulakos, Kiriakos N

2011-11-01

In this paper, we consider the problem of imaging a scene with a given depth of field at a given exposure level in the shortest amount of time possible. We show that by 1) collecting a sequence of photos and 2) controlling the aperture, focus, and exposure time of each photo individually, we can span the given depth of field in less total time than it takes to expose a single narrower-aperture photo. Using this as a starting point, we obtain two key results. First, for lenses with continuously variable apertures, we derive a closed-form solution for the globally optimal capture sequence, i.e., that collects light from the specified depth of field in the most efficient way possible. Second, for lenses with discrete apertures, we derive an integer programming problem whose solution is the optimal sequence. Our results are applicable to off-the-shelf cameras and typical photography conditions, and advocate the use of dense, wide-aperture photo sequences as a light-efficient alternative to single-shot, narrow-aperture photography.

Single Still Image

NASA Technical Reports Server (NTRS)

1999-01-01

This narrow angle image taken by Cassini's camera system of the Moon is one of the best of a sequence of narrow angle frames taken as the spacecraft passed by the Moon on the way to its closest approach with Earth on August 17, 1999. The 80 millisecond exposure was taken through a spectral filter centered at 0.33 microns; the filter bandpass was 85 Angstroms wide. The spatial scale of the image is about 1.4 miles per pixel (about 2.3 kilometers). The imaging data were processed and released by the Cassini Imaging Central Laboratory for Operations (CICLOPS) at the University of Arizona's Lunar and Planetary Laboratory, Tucson, AZ.

Photo Credit: NASA/JPL/Cassini Imaging Team/University of Arizona

Cassini, launched in 1997, is a joint mission of NASA, the European Space Agency and Italian Space Agency. The mission is managed by NASA's Jet Propulsion Laboratory, Pasadena, CA, for NASA's Office of Space Science, Washington DC. JPL is a division of the California Institute of Technology, Pasadena, CA.

KSC-2009-3755

NASA Image and Video Library

2009-06-18

CAPE CANAVERAL, Fla. – A closeup of NASA's Lunar Reconnaissance Orbiter, or LRO, and NASA's Lunar Crater Observation and Sensing Satellite, known as LCROSS, ready for liftoff on an Atlas V/Centaur rocket from Launch Pad 41 at Cape Canaveral Air Force Station in Florida. LRO and LCROSS are the first missions in NASA's plan to return humans to the moon and begin establishing a lunar outpost by 2020. The LRO also includes seven instruments that will help NASA characterize the moon's surface: DIVINER, LAMP, LEND, LOLA , CRATER, Mini-RF and LROC. Launch is scheduled for 5:12 p.m. EDT June 18. Photo credit: NASA/Ken Thornsley

KSC-2009-3753

NASA Image and Video Library

2009-06-18

CAPE CANAVERAL, Fla. – NASA's Lunar Reconnaissance Orbiter, or LRO, and NASA's Lunar Crater Observation and Sensing Satellite, known as LCROSS, stand ready for liftoff on an Atlas V/Centaur rocket from Launch Pad 41 at Cape Canaveral Air Force Station in Florida. LRO and LCROSS are the first missions in NASA's plan to return humans to the moon and begin establishing a lunar outpost by 2020. The LRO also includes seven instruments that will help NASA characterize the moon's surface: DIVINER, LAMP, LEND, LOLA , CRATER, Mini-RF and LROC. Launch is scheduled for 5:12 p.m. EDT June 18. Photo credit: NASA/Ken Thornsley

KSC-2009-3765

NASA Image and Video Library

2009-06-18

CAPE CANAVERAL, Fla. – Trailing a column of smoke, NASA's Lunar Reconnaissance Orbiter, or LRO, and NASA's Lunar Crater Observation and Sensing Satellite, known as LCROSS, lifts off from Launch Pad 41 at Cape Canaveral Air Force Station in Florida. LRO and LCROSS are the first missions in NASA's plan to return humans to the moon and begin establishing a lunar outpost by 2020. The LRO also includes seven instruments that will help NASA characterize the moon's surface: DIVINER, LAMP, LEND, LOLA , CRATER, Mini-RF and LROC. Launch was on-time at 5:32 p.m. EDT June 18. Photo credit: NASA/Tom Farrar

KSC-2009-3763

NASA Image and Video Library

2009-06-18

CAPE CANAVERAL, Fla. – Rising above the lightning towers around the pad, NASA's Lunar Reconnaissance Orbiter, or LRO, and NASA's Lunar Crater Observation and Sensing Satellite, known as LCROSS, lifts off from Launch Pad 41 at Cape Canaveral Air Force Station in Florida. LRO and LCROSS are the first missions in NASA's plan to return humans to the moon and begin establishing a lunar outpost by 2020. The LRO also includes seven instruments that will help NASA characterize the moon's surface: DIVINER, LAMP, LEND, LOLA , CRATER, Mini-RF and LROC. Launch was on-time at 5:32 p.m. EDT June 18. Photo credit: NASA/Sandra Joseph

KSC-2009-3764

NASA Image and Video Library

2009-06-18

CAPE CANAVERAL, Fla. – Trailing a column of smoke, NASA's Lunar Reconnaissance Orbiter, or LRO, and NASA's Lunar Crater Observation and Sensing Satellite, known as LCROSS, lifts off from Launch Pad 41 at Cape Canaveral Air Force Station in Florida. LRO and LCROSS are the first missions in NASA's plan to return humans to the moon and begin establishing a lunar outpost by 2020. The LRO also includes seven instruments that will help NASA characterize the moon's surface: DIVINER, LAMP, LEND, LOLA , CRATER, Mini-RF and LROC. Launch was on-time at 5:32 p.m. EDT June 18. Photo credit: NASA/Tom Farrar

KSC-2009-3782

NASA Image and Video Library

2009-06-18

CAPE CANAVERAL, Fla. – NASA's Lunar Reconnaissance Orbiter, or LRO, and NASA's Lunar Crater Observation and Sensing Satellite, known as LCROSS, lifts off from Launch Pad 41 at Cape Canaveral Air Force Station in Florida atop an Atlas V/Centaur rocket. LRO and LCROSS are the first missions in NASA's plan to return humans to the moon and begin establishing a lunar outpost by 2020. The LRO also includes seven instruments that will help NASA characterize the moon's surface: DIVINER, LAMP, LEND, LOLA , CRATER, Mini-RF and LROC. Launch was on-time at 5:32 p.m. EDT. Photo credit: NASA/Tom Farrar, Kevin O'Connell

KSC-2009-3786

NASA Image and Video Library

2009-06-18

CAPE CANAVERAL, Fla. – Trailing a column of fire, the Atlas V/Centaur carrying NASA's Lunar Reconnaissance Orbiter, or LRO, and NASA's Lunar Crater Observation and Sensing Satellite, known as LCROSS, hurtles off Launch Complex 41 at Cape Canaveral Air Force Station in Florida. LRO and LCROSS are the first missions in NASA's plan to return humans to the moon and begin establishing a lunar outpost by 2020. The LRO also includes seven instruments that will help NASA characterize the moon's surface: DIVINER, LAMP, LEND, LOLA , CRATER, Mini-RF and LROC. Launch was on-time at 5:32 p.m. EDT. Photo credit: NASA/Sandra Joseph, Tony Gray

KSC-2009-3749

NASA Image and Video Library

2009-06-17

CAPE CANAVERAL, Fla. – The Atlas V/Centaur rocket with NASA's Lunar Reconnaissance Orbiter, or LRO, and NASA's Lunar Crater Observation and Sensing Satellite, known as LCROSS, on top are on the pad at Launch Complex-41 on Cape Canaveral Air Force Station in Florida. LRO and LCROSS are the first missions in NASA's plan to return humans to the moon and begin establishing a lunar outpost by 2020. The LRO also includes seven instruments that will help NASA characterize the moon's surface: DIVINER, LAMP, LEND, LOLA, CRATER, Mini-RF and LROC. Launch is scheduled for 5:22 p.m. EDT June 18 . Photo credit: NASA/Jack Pfaller

KSC-2009-3785

NASA Image and Video Library

2009-06-18

CAPE CANAVERAL, Fla. – Trailing a column of fire, the Atlas V/Centaur carrying NASA's Lunar Reconnaissance Orbiter, or LRO, and NASA's Lunar Crater Observation and Sensing Satellite, known as LCROSS, hurtles off Launch Complex 41 at Cape Canaveral Air Force Station in Florida. LRO and LCROSS are the first missions in NASA's plan to return humans to the moon and begin establishing a lunar outpost by 2020. The LRO also includes seven instruments that will help NASA characterize the moon's surface: DIVINER, LAMP, LEND, LOLA , CRATER, Mini-RF and LROC. Launch was on-time at 5:32 p.m. EDT. Photo credit: NASA/Sandra Joseph, Tony Gray

Mastcam Special Filters Help Locate Variations Ahead

NASA Image and Video Library

2017-11-01

This pair of images from the Mast Camera (Mastcam) on NASA's Curiosity rover illustrates how special filters are used to scout terrain ahead for variations in the local bedrock. The upper panorama is in the Mastcam's usual full color, for comparison. The lower panorama of the same scene, in false color, combines three exposures taken through different "science filters," each selecting for a narrow band of wavelengths. Filters and image processing steps were selected to make stronger signatures of hematite, an iron-oxide mineral, evident as purple. Hematite is of interest in this area of Mars -- partway up "Vera Rubin Ridge" on lower Mount Sharp -- as holding clues about ancient environmental conditions under which that mineral originated. In this pair of panoramas, the strongest indications of hematite appear related to areas where the bedrock is broken up. With information from this Mastcam reconnaissance, the rover team selected destinations in the scene for close-up investigations to gain understanding about the apparent patchiness in hematite spectral features. The Mastcam's left-eye camera took the component images of both panoramas on Sept. 12, 2017, during the 1,814th Martian day, or sol, of Curiosity's work on Mars. The view spans from south-southeast on the left to south-southwest on the right. The foreground across the bottom of the scene is about 50 feet (about 15 meters) wide. Figure 1 includes scale bars of 1 meter (3.3 feet) in the middle distance and 5 meters (16 feet) at upper right. Curiosity's Mastcam combines two cameras: the right eye with a telephoto lens and the left eye with a wider-angle lens. Each camera has a filter wheel that can be rotated in front of the lens for a choice of eight different filters. One filter for each camera is clear to all visible light, for regular full-color photos, and another is specifically for viewing the Sun. Some of the other filters were selected to admit wavelengths of light that are useful for identifying iron minerals. Each of the filters used for the lower panorama shown here admits light from a narrow band of wavelengths, extending to only about 5 to 10 nanometers longer or shorter than the filter's central wavelength. The three observations combined into this product used filters centered at three near-infrared wavelengths: 751 nanometers, 867 nanometers and 1,012 nanometers. Hematite distinctively absorbs some frequencies of infrared light more than others. Usual color photographs from digital cameras -- such as the upper panorama here from Mastcam -- combine information from red, green and blue filtering. The filters are in a microscopic grid in a "Bayer" filter array situated directly over the detector behind the lens, with wider bands of wavelengths. The colors of the upper panorama, as with most featured images from Mastcam, have been tuned with a color adjustment similar to white balancing for approximating how the rocks and sand would appear under daytime lighting conditions on Earth. https://photojournal.jpl.nasa.gov/catalog/PIA22065

High-resolution, high-sensitivity, ground-based solar spectropolarimetry with a new fast imaging polarimeter. I. Prototype characterization

NASA Astrophysics Data System (ADS)

Iglesias, F. A.; Feller, A.; Nagaraju, K.; Solanki, S. K.

2016-05-01

Context. Remote sensing of weak and small-scale solar magnetic fields is of utmost relevance when attempting to respond to a number of important open questions in solar physics. This requires the acquisition of spectropolarimetric data with high spatial resolution (~10-1 arcsec) and low noise (10-3 to 10-5 of the continuum intensity). The main limitations to obtain these measurements from the ground, are the degradation of the image resolution produced by atmospheric seeing and the seeing-induced crosstalk (SIC). Aims: We introduce the prototype of the Fast Solar Polarimeter (FSP), a new ground-based, high-cadence polarimeter that tackles the above-mentioned limitations by producing data that are optimally suited for the application of post-facto image restoration, and by operating at a modulation frequency of 100 Hz to reduce SIC. Methods: We describe the instrument in depth, including the fast pnCCD camera employed, the achromatic modulator package, the main calibration steps, the effects of the modulation frequency on the levels of seeing-induced spurious signals, and the effect of the camera properties on the image restoration quality. Results: The pnCCD camera reaches 400 fps while keeping a high duty cycle (98.6%) and very low noise (4.94 e- rms). The modulator is optimized to have high (>80%) total polarimetric efficiency in the visible spectral range. This allows FSP to acquire 100 photon-noise-limited, full-Stokes measurements per second. We found that the seeing induced signals that are present in narrow-band, non-modulated, quiet-sun measurements are (a) lower than the noise (7 × 10-5) after integrating 7.66 min, (b) lower than the noise (2.3 × 10-4) after integrating 1.16 min and (c) slightly above the noise (4 × 10-3) after restoring case (b) by means of a multi-object multi-frame blind deconvolution. In addition, we demonstrate that by using only narrow-band images (with low S/N of 13.9) of an active region, we can obtain one complete set of high-quality restored measurements about every 2 s.

14. View toward the northwest corner of the basement in ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

14. View toward the northwest corner of the basement in the north segment of the building. Portions of the basement floor are earth, and portions are concrete. For some undetermined reason an unbonded, narrow panel of brick occurs in the west (left) wall. A corbeled brick footing is seen under this panel, as if the panel is carrying a concentrated load. An identical element occurs to the left, outside the camera's view. These 'columns' may support the second-story brick facade over the ground floor store windows. Credit GADA/MRM. - Stroud Building, 31-33 North Central Avenue, Phoenix, Maricopa County, AZ

Northern Summer on Titan

NASA Image and Video Library

2017-06-14

NASA's Cassini spacecraft sees bright methane clouds drifting in the summer skies of Saturn's moon Titan, along with dark hydrocarbon lakes and seas clustered around the north pole. Compared to earlier in Cassini's mission, most of the surface in the moon's northern high latitudes is now illuminated by the sun. The image was taken with the Cassini spacecraft narrow-angle camera on June 9, 2017, using a spectral filter that preferentially admits wavelengths of near-infrared light centered at 938 nanometers. Cassini obtained the view at a distance of about 315,000 miles (507,000 kilometers) from Titan. https://photojournal.jpl.nasa.gov/catalog/PIA21615

Rhea and Her Craters

NASA Image and Video Library

2005-01-17

This Cassini image shows predominantly the impact-scarred leading hemisphere of Saturn's icy moon Rhea (1,528 kilometers, or 949 miles across). The image was taken in visible light with the Cassini spacecraft narrow angle camera on Dec. 12, 2004, at a distance of 2 million kilometers (1.2 million miles) from Rhea and at a Sun-Rhea-spacecraft, or phase, angle of 30 degrees. The image scale is about 12 kilometers (7.5 miles) per pixel. The image has been magnified by a factor of two and contrast enhanced to aid visibility. http://photojournal.jpl.nasa.gov/catalog/PIA06564

Ultraviolet Enceladus

NASA Image and Video Library

2004-09-23

Looking beyond Saturn's south pole, this was the Cassini spacecraft's view of the distant, icy moon Enceladus on July 28, 2004. The planet itself shows few obvious features at these ultraviolet wavelengths, due to scattering of light by molecules of the gases high in the atmosphere. Enceladus is 499 kilometers (310 miles) wide. The image was taken with the Cassini spacecraft narrow angle camera at a distance of 7.4 million kilometers (4.6 million miles) from Saturn through a filter sensitive to ultraviolet wavelengths of light. The image scale is 44 kilometers (27 miles) per pixel of Saturn. http://photojournal.jpl.nasa.gov/catalog/PIA06483

Enhanced video indirect ophthalmoscopy (VIO) via robust mosaicing.

PubMed

Estrada, Rolando; Tomasi, Carlo; Cabrera, Michelle T; Wallace, David K; Freedman, Sharon F; Farsiu, Sina

2011-10-01

Indirect ophthalmoscopy (IO) is the standard of care for evaluation of the neonatal retina. When recorded on video from a head-mounted camera, IO images have low quality and narrow Field of View (FOV). We present an image fusion methodology for converting a video IO recording into a single, high quality, wide-FOV mosaic that seamlessly blends the best frames in the video. To this end, we have developed fast and robust algorithms for automatic evaluation of video quality, artifact detection and removal, vessel mapping, registration, and multi-frame image fusion. Our experiments show the effectiveness of the proposed methods.

Fluorescence excited in a thunderstorm atmosphere by relativistic runaway electron avalanches

NASA Astrophysics Data System (ADS)

Babich, L. P.; Bochkov, E. I.

2017-05-01

The spectrum and spatiotemporal evolution of the fluorescence of an atmospheric discharge developing in the regime of relativistic runaway electron avalanche (RREA) generation have been calculated without involving the relativistic feedback. The discharges generating narrow bipolar pulses, along with the discharges responsible for terrestrial gamma-ray flashes, are shown to be relatively dark. Nevertheless, the fluorescence excited by a discharge involving RREAs can be recorded with cameras used to record high-altitude optical phenomena. A possible connection between a certain class of optical phenomena observed at the tops of thunderclouds and RREA emission is pointed out.

Preliminary optical design of PANIC, a wide-field infrared camera for CAHA

NASA Astrophysics Data System (ADS)

Cárdenas, M. C.; Rodríguez Gómez, J.; Lenzen, R.; Sánchez-Blanco, E.

2008-07-01

In this paper, we present the preliminary optical design of PANIC (PAnoramic Near Infrared camera for Calar Alto), a wide-field infrared imager for the Calar Alto 2.2 m telescope. The camera optical design is a folded single optical train that images the sky onto the focal plane with a plate scale of 0.45 arcsec per 18 μm pixel. A mosaic of four Hawaii 2RG of 2k x 2k made by Teledyne is used as detector and will give a field of view of 31.9 arcmin x 31.9 arcmin. This cryogenic instrument has been optimized for the Y, J, H and K bands. Special care has been taken in the selection of the standard IR materials used for the optics in order to maximize the instrument throughput and to include the z band. The main challenges of this design are: to produce a well defined internal pupil which allows reducing the thermal background by a cryogenic pupil stop; the correction of off-axis aberrations due to the large field available; the correction of chromatic aberration because of the wide spectral coverage; and the capability of introduction of narrow band filters (~1%) in the system minimizing the degradation in the filter passband without a collimated stage in the camera. We show the optomechanical error budget and compensation strategy that allows our as built design to met the performances from an optical point of view. Finally, we demonstrate the flexibility of the design showing the performances of PANIC at the CAHA 3.5m telescope.

Sublimation of icy aggregates in the coma of comet 67P/Churyumov-Gerasimenko detected with the OSIRIS cameras on board Rosetta

NASA Astrophysics Data System (ADS)

Gicquel, A.; Vincent, J.-B.; Agarwal, J.; A'Hearn, M. F.; Bertini, I.; Bodewits, D.; Sierks, H.; Lin, Z.-Y.; Barbieri, C.; Lamy, P. L.; Rodrigo, R.; Koschny, D.; Rickman, H.; Keller, H. U.; Barucci, M. A.; Bertaux, J.-L.; Besse, S.; Cremonese, G.; Da Deppo, V.; Davidsson, B.; Debei, S.; Deller, J.; De Cecco, M.; Frattin, E.; El-Maarry, M. R.; Fornasier, S.; Fulle, M.; Groussin, O.; Gutiérrez, P. J.; Gutiérrez-Marquez, P.; Güttler, C.; Höfner, S.; Hofmann, M.; Hu, X.; Hviid, S. F.; Ip, W.-H.; Jorda, L.; Knollenberg, J.; Kovacs, G.; Kramm, J.-R.; Kührt, E.; Küppers, M.; Lara, L. M.; Lazzarin, M.; Moreno, J. J. Lopez; Lowry, S.; Marzari, F.; Masoumzadeh, N.; Massironi, M.; Moreno, F.; Mottola, S.; Naletto, G.; Oklay, N.; Pajola, M.; Pommerol, A.; Preusker, F.; Scholten, F.; Shi, X.; Thomas, N.; Toth, I.; Tubiana, C.

2016-11-01

Beginning in 2014 March, the OSIRIS (Optical, Spectroscopic, and Infrared Remote Imaging System) cameras began capturing images of the nucleus and coma (gas and dust) of comet 67P/Churyumov-Gerasimenko using both the wide angle camera (WAC) and the narrow angle camera (NAC). The many observations taken since July of 2014 have been used to study the morphology, location, and temporal variation of the comet's dust jets. We analysed the dust monitoring observations shortly after the southern vernal equinox on 2015 May 30 and 31 with the WAC at the heliocentric distance Rh = 1.53 AU, where it is possible to observe that the jet rotates with the nucleus. We found that the decline of brightness as a function of the distance of the jet is much steeper than the background coma, which is a first indication of sublimation. We adapted a model of sublimation of icy aggregates and studied the effect as a function of the physical properties of the aggregates (composition and size). The major finding of this paper was that through the sublimation of the aggregates of dirty grains (radius a between 5 and 50 μm) we were able to completely reproduce the radial brightness profile of a jet beyond 4 km from the nucleus. To reproduce the data, we needed to inject a number of aggregates between 8.5 × 1013 and 8.5 × 1010 for a = 5 and 50 μm, respectively, or an initial mass of H2O ice around 22 kg.

LROC assessment of non-linear filtering methods in Ga-67 SPECT imaging

NASA Astrophysics Data System (ADS)

De Clercq, Stijn; Staelens, Steven; De Beenhouwer, Jan; D'Asseler, Yves; Lemahieu, Ignace

2006-03-01

In emission tomography, iterative reconstruction is usually followed by a linear smoothing filter to make such images more appropriate for visual inspection and diagnosis by a physician. This will result in a global blurring of the images, smoothing across edges and possibly discarding valuable image information for detection tasks. The purpose of this study is to investigate which possible advantages a non-linear, edge-preserving postfilter could have on lesion detection in Ga-67 SPECT imaging. Image quality can be defined based on the task that has to be performed on the image. This study used LROC observer studies based on a dataset created by CPU-intensive Gate Monte Carlo simulations of a voxelized digital phantom. The filters considered in this study were a linear Gaussian filter, a bilateral filter, the Perona-Malik anisotropic diffusion filter and the Catte filtering scheme. The 3D MCAT software phantom was used to simulate the distribution of Ga-67 citrate in the abdomen. Tumor-present cases had a 1-cm diameter tumor randomly placed near the edges of the anatomical boundaries of the kidneys, bone, liver and spleen. Our data set was generated out of a single noisy background simulation using the bootstrap method, to significantly reduce the simulation time and to allow for a larger observer data set. Lesions were simulated separately and added to the background afterwards. These were then reconstructed with an iterative approach, using a sufficiently large number of MLEM iterations to establish convergence. The output of a numerical observer was used in a simplex optimization method to estimate an optimal set of parameters for each postfilter. No significant improvement was found for using edge-preserving filtering techniques over standard linear Gaussian filtering.

Chappy Oblique

NASA Image and Video Library

2017-12-08

Looking east to west across the rim and down into Chaplygin crater reveals this beautiful example of a fresh young crater and its perfectly preserved ejecta blanket. The delicate patterns of flow across, over, and down local topography clearly show that ejecta traveled as a ground hugging flow for great distances, rather than simply being tossed out on a ballistic trajectory. Very near the rim lies a dark, lacy, discontinuous crust of now frozen impact melt. Clearly this dark material is on top of the bright material so it was the very last material ejected from the crater. The melt was formed as the tremendous energy of impact was converted to heat and the lunar crust was melted at the impact point. As the crater rebounded and material sloughed down the walls of the deforming crater the melt was splashed out over the rim and froze. Its low reflectance is mostly due to a high percentage of glass because the melt cooled so quickly that minerals did not have time to crystallize. The fact that the delicate splash patterns are so well preserved testifies to the very young age of this crater. But how young? For comparison "Chappy" (informal name) is 200 m larger than Meteor crater (1200 m diameter) in Arizona, which is about 50,000 years old. Craters of this size form every 100,000 years or so on the Moon and the Earth. Since there are very few superposed craters on Chappy, and its ejecta is so perfectly preserved it may be much younger than Meteor crater. However, we can't know the true true absolute age of "Chappy" until we can obtain a sample of its impact melt for radiometric age dating. Investigate all of Chappy's ejecta, at full resolution: lroc.sese.asu.edu/posts/901 Credit: NASA/Goddard/Arizona State University/LRO/LROC

Utility as a rationale for choosing observer performance assessment paradigms for detection tasks in medical imaging.

PubMed

Wunderlich, Adam; Abbey, Craig K

2013-11-01

Studies of lesion detectability are often carried out to evaluate medical imaging technology. For such studies, several approaches have been proposed to measure observer performance, such as the receiver operating characteristic (ROC), the localization ROC (LROC), the free-response ROC (FROC), the alternative free-response ROC (AFROC), and the exponentially transformed FROC (EFROC) paradigms. Therefore, an experimenter seeking to carry out such a study is confronted with an array of choices. Traditionally, arguments for different approaches have been made on the basis of practical considerations (statistical power, etc.) or the gross level of analysis (case-level or lesion-level). This article contends that a careful consideration of utility should form the rationale for matching the assessment paradigm to the clinical task of interest. In utility theory, task performance is commonly evaluated with total expected utility, which integrates the various event utilities against the probability of each event. To formalize the relationship between expected utility and the summary curve associated with each assessment paradigm, the concept of a "natural" utility structure is proposed. A natural utility structure is defined for a summary curve when the variables associated with the summary curve axes are sufficient for computing total expected utility, assuming that the disease prevalence is known. Natural utility structures for ROC, LROC, FROC, AFROC, and EFROC curves are introduced, clarifying how the utilities of correct and incorrect decisions are aggregated by summary curves. Further, conditions are given under which general utility structures for localization-based methodologies reduce to case-based assessment. Overall, the findings reveal how summary curves correspond to natural utility structures of diagnostic tasks, suggesting utility as a motivating principle for choosing an assessment paradigm.

Task Equivalence for Model and Human-Observer Comparisons in SPECT Localization Studies

NASA Astrophysics Data System (ADS)

Sen, Anando; Kalantari, Faraz; Gifford, Howard C.

2016-06-01

While mathematical model observers are intended for efficient assessment of medical imaging systems, their findings should be relevant for human observers as the primary clinical end users. We have investigated whether pursuing equivalence between the model and human-observer tasks can help ensure this goal. A localization receiver operating characteristic (LROC) study tested prostate lesion detection in simulated In-111 SPECT imaging with anthropomorphic phantoms. The test images were 2D slices extracted from reconstructed volumes. The iterative ordered sets expectation-maximization (OSEM) reconstruction algorithm was used with Gaussian postsmoothing. Variations in the number of iterations and the level of postfiltering defined the test strategies in the study. Human-observer performance was compared with that of a visual-search (VS) observer, a scanning channelized Hotelling observer, and a scanning channelized nonprewhitening (CNPW) observer. These model observers were applied with precise information about the target regions of interest (ROIs). ROI knowledge was a study variable for the human observers. In one study format, the humans read the SPECT image alone. With a dual-modality format, the SPECT image was presented alongside an anatomical image slice extracted from the density map of the phantom. Performance was scored by area under the LROC curve. The human observers performed significantly better with the dual-modality format, and correlation with the model observers was also improved. Given the human-observer data from the SPECT study format, the Pearson correlation coefficients for the model observers were 0.58 (VS), -0.12 (CH), and -0.23 (CNPW). The respective coefficients based on the human-observer data from the dual-modality study were 0.72, 0.27, and -0.11. These results point towards the continued development of the VS observer for enhancing task equivalence in model-observer studies.

Effect of Using 2 mm Voxels on Observer Performance for PET Lesion Detection

NASA Astrophysics Data System (ADS)

Morey, A. M.; Noo, Frédéric; Kadrmas, Dan J.

2016-06-01

Positron emission tomography (PET) images are typically reconstructed with an in-plane pixel size of approximately 4 mm for cancer imaging. The objective of this work was to evaluate the effect of using smaller pixels on general oncologic lesion-detection. A series of observer studies was performed using experimental phantom data from the Utah PET Lesion Detection Database, which modeled whole-body FDG PET cancer imaging of a 92 kg patient. The data comprised 24 scans over 4 days on a Biograph mCT time-of-flight (TOF) PET/CT scanner, with up to 23 lesions (diam. 6-16 mm) distributed throughout the phantom each day. Images were reconstructed with 2.036 mm and 4.073 mm pixels using ordered-subsets expectation-maximization (OSEM) both with and without point spread function (PSF) modeling and TOF. Detection performance was assessed using the channelized non-prewhitened numerical observer with localization receiver operating characteristic (LROC) analysis. Tumor localization performance and the area under the LROC curve were then analyzed as functions of the pixel size. In all cases, the images with 2 mm pixels provided higher detection performance than those with 4 mm pixels. The degree of improvement from the smaller pixels was larger than that offered by PSF modeling for these data, and provided roughly half the benefit of using TOF. Key results were confirmed by two human observers, who read subsets of the test data. This study suggests that a significant improvement in tumor detection performance for PET can be attained by using smaller voxel sizes than commonly used at many centers. The primary drawback is a 4-fold increase in reconstruction time and data storage requirements.

A Co-Investigator Project for the Cornell University Cleft Accelerated Plasma Experimental Rocket-CAPER

NASA Technical Reports Server (NTRS)

Deehr, Charles S.

1999-01-01

The CAPER rocket campaign was to follow the SCIFER experiment as a detailed study of the ion acceleration processes in the Cleft Ion Fountain (CIF) above 1000 km altitude. The SCIFER rocket demonstrated that the experiment was feasible and that the CIF acceleration processes on the dayside are different from those observed in the discrete aurora on the nightside. The responsibility of the GI/UAF co-investigator project was to provide the real-time acquisition and display of large-and small-scale ground observations, and satellite solar wind data at the launch control center at Longyearbyen, Svalbard for the determination of the launch conditions and the later interpretation of the rocket observations. The rocket campaign was proposed for January of 1998, but was slipped to January of 1999. The rocket was launched on January 21, 1999 at 06 h 13 m 30 s UT. All of the GI/UAF co-investigator systems functioned well, except the narrow-field TV camera which was to follow the 140 km conjugate of the payload on command from GPS tracking data sent from Andoya. The data were not available during the flight, and the camera tracked the nominal conjugate. Unfortunately, the trajectory was well west of nominal, so no useful narrow-field conjugate data were acquired . In addition, the payload missed the region of more intense precipitation, brighter aurora, stronger currents, and likely large fluxes of transverse ion acceleration. On the other hand, good data were acquired across a region of the ionosphere that appears to have had a double convection boundary because of the IMF switching its z component shortly before launch. These data are important for understanding the reaction of the magnetosphere and ionosphere to changes in the IMF.

Detection of rip current using camera monitoring techniques

NASA Astrophysics Data System (ADS)

Kim, T.

2016-02-01

Rip currents are approximately shore normal seaward flows which are strong, localized and rather narrow. They are known that stacked water by longshore currents suddenly flow back out to sea as rip currents. They are transient phenomena and their generation time and location are unpredictable. They are also doing significant roles for offshore sediment transport and beach erosion. Rip currents can be very hazardous to swimmers or floaters because of their strong seaward flows and sudden depth changes by narrow and strong flows. Because of its importance in terms of safety, shoreline evolution and pollutant transport, a number of studies have been attempted to find out their mechanisms. However, understanding of rip currents is still not enough to make warning to people in the water by predicting their location and time. This paper investigates the development of rip currents using camera images. Since rip currents are developed by longshore currents, the observed longshore current variations in space and time can be used to detect rip current generation. Most of the time convergence of two longshore currents in the opposite direction is the outbreak of rip current. In order to observe longshore currents, an optical current meter(OCM) technique proposed by Chickadel et al.(2003) is used. The relationship between rip current generation time and longshore current velocity variation observed by OCM is analyzed from the images taken on the shore. The direct measurement of rip current velocity is also tested using image analysis techniques. Quantitative estimation of rip current strength is also conducted by using average and variance image of rip current area. These efforts will contribute to reduce the hazards of swimmers by prediction and warning of rip current generation.

Stellar Occultations in the Coma of Comet 67/P Chuyumov-Gerasimenko Observed by the OSIRIS Camera System

NASA Astrophysics Data System (ADS)

Moissl, Richard; Kueppers, Michael

2016-10-01

In this paper we present the results of an analysis on a large part of the existing Image data from the OSIRIS camera system onboard the Rosetta Spacecraft, in which stars of sufficient brightness (down to a limiting magnitude of 6) have been observed through the coma of Comet 67/P Churyumov-Gerasimenko ("C-G"). Over the course of the Rosetta main mission the Coma of the comet underwent large changes in density and structure, owed to the changing insolation along the orbit of C-G. We report on the changes of the stellar signals in the wavelength ranges, covered by the filters of the OSIRIS Narrow-Angle (NAC) and Wide-Angle (WAC) cameras.Acknowledgements: OSIRIS was built by a consortium led by the Max-Planck-Institut für Sonnensystemforschung, Göttingen, Germany, in collaboration with CISAS, University of Padova, Italy, the Laboratoire d'Astrophysique de Marseille, France, the Instituto de Astrofísica de Andalucia, CSIC, Granada, Spain, the Scientific Support Office of the European Space Agency, Noordwijk, The Netherlands, the Instituto Nacional de Técnica Aeroespacial, Madrid, Spain, the Universidad Politéchnica de Madrid, Spain, the Department of Physics and Astronomy of Uppsala University, Sweden, and the Institut für Datentechnik und Kommunikationsnetze der Technischen Universität Braunschweig, Germany.

Morphology and Dynamics of Jets of Comet 67P Churyumov-Gerasimenko: Early Phase Development

NASA Astrophysics Data System (ADS)

Lin, Zhong-Yi; Ip, Wing-Huen; Lai, Ian-Lin; Lee, Jui-Chi; Pajola, Maurizio; Lara, Luisa; Gutierrez, Pedro; Rodrigo, Rafael; Bodewits, Dennis; A'Hearn, Mike; Vincent, Jean-Baptiste; Agarwal, Jessica; Keller, Uwe; Mottola, Stefano; Bertini, Ivano; Lowry, Stephen; Rozek, Agata; Liao, Ying; Rosetta Osiris Coi Team

2015-04-01

The scientific camera, OSIRIS (Optical, Spectroscopic, and Infrared Remote Imaging System), onboard the Rosetta spacecraft comprises a Narrow Angle Camera (NAC) for nucleus surface and dust studies and a Wide Angle Camera (WAC) for the wide field of dust and gas coma investigations. The dynamical behavior of jets in the dust coma continuously monitored by using dust filters from the arrival at the comet (August 2014) throughout the mapping phase (Oct. 2014) is described here. The analysis will cover the study of the time variability of jets, the source regions of these jets, the excess brightness of jets relative to the averaged coma brightness, and the brightness distribution of dust jets along the projected distance. The jets detected between August and September originated mostly from the neck region (Hapi). Morphological changes appeared over a time scale of several days in September. The brightness slope of the dust jets is much steeper than the background coma. This might be related to the sublimation or fragmentation of the emitted dust grains. Inter-comparison with results from other experiments will be necessary to understand the difference between the dust emitted from Hapi and those from the head and the body of the nucleus surface. The physical properties of the Hapi jets will be compared to dust jets (and their source regions) to emerge as comet 67P moves around the perihelion.

MicroCameras and Photometers (MCP) on board the TARANIS satellite

NASA Astrophysics Data System (ADS)

Farges, T.; Hébert, P.; Le Mer-Dachard, F.; Ravel, K.; Gaillac, S.

2017-12-01

TARANIS (Tool for the Analysis of Radiations from lightNing and Sprites) is a CNES micro satellite. Its main objective is to study impulsive transfers of energy between the Earth atmosphere and the space environment. It will be sun-synchronous at an altitude of 700 km. It will be launched in 2019 for at least 2 years. Its payload is composed of several electromagnetic instruments in different wavelengths (from gamma-rays to radio waves including optical). TARANIS instruments are currently in calibration and qualification phase. The purpose is to present the MicroCameras and Photometers (MCP) design, to show its performances after its recent characterization and at last to discuss the scientific objectives and how we want to answer it with the MCP observations. The MicroCameras, developed by Sodern, are dedicated to the spatial description of TLEs and their parent lightning. They are able to differentiate sprite and lightning thanks to two narrow bands ([757-767 nm] and [772-782 nm]) that provide simultaneous pairs of images of an Event. Simulation results of the differentiation method will be shown. After calibration and tests, the MicroCameras are now delivered to the CNES for integration on the payload. The Photometers, developed by Bertin Technologies, will provide temporal measurements and spectral characteristics of TLEs and lightning. There are key instrument because of their capability to detect on-board TLEs and then switch all the instruments of the scientific payload in their high resolution acquisition mode. Photometers use four spectral bands in the [170-260 nm], [332-342 nm], [757-767 nm] and [600-900 nm] and have the same field of view as cameras. The on-board TLE detection algorithm remote-controlled parameters have been tuned before launch using the electronic board and simulated or real events waveforms. After calibration, the Photometers are now going through the environmental tests. They will be delivered to the CNES for integration on the payload in September 2017.

KSC-2009-3192

NASA Image and Video Library

2009-05-15

CAPE CANAVERAL, Fla. – At Astrotech Space Operations Facility in Titusville, Fla., technicians closely watch as the fairing halves move together to enclose NASA's Lunar Reconnaissance Orbiter, or LRO, and NASA's Lunar Crater Observation and Sensing Satellite, known as LCROSS. The fairing is a molded structure that fits flush with the outside surface of the rocket and forms an aerodynamically smooth nose cone, protecting the spacecraft during launch and ascent. The LRO includes five instruments: DIVINER, LAMP, LEND, LOLA and LROC. They will be launched aboard an Atlas V/Centaur rocket no earlier than June 17 from Launch Complex-41 on Cape Canaveral Air Force Station in Florida. Photo credit: NASA/Jack Pfaller

KSC-2009-3787

NASA Image and Video Library

2009-06-18

CAPE CANAVERAL, Fla. – Trailing a column of fire, the Atlas V/Centaur carrying NASA's Lunar Reconnaissance Orbiter, or LRO, and NASA's Lunar Crater Observation and Sensing Satellite, known as LCROSS, races above the lightning tower at left on Launch Complex 41 at Cape Canaveral Air Force Station in Florida. LRO and LCROSS are the first missions in NASA's plan to return humans to the moon and begin establishing a lunar outpost by 2020. The LRO also includes seven instruments that will help NASA characterize the moon's surface: DIVINER, LAMP, LEND, LOLA , CRATER, Mini-RF and LROC. Launch was on-time at 5:32 p.m. EDT. Photo credit: NASA/Sandra Joseph, Tony Gray

KSC-2009-3748

NASA Image and Video Library

2009-06-17

CAPE CANAVERAL, Fla. – On Launch Complex-41 on Cape Canaveral Air Force Station in Florida, the Atlas V/Centaur rocket with NASA's Lunar Reconnaissance Orbiter, or LRO, and NASA's Lunar Crater Observation and Sensing Satellite, known as LCROSS, on top reach the launch pad. Circling the pad are the protective lightning towers. LRO and LCROSS are the first missions in NASA's plan to return humans to the moon and begin establishing a lunar outpost by 2020. The LRO also includes seven instruments that will help NASA characterize the moon's surface: DIVINER, LAMP, LEND, LOLA, CRATER, Mini-RF and LROC. Launch is scheduled for 5:22 p.m. EDT June 18 . Photo credit: NASA/Jack Pfaller

KSC-2009-3742

NASA Image and Video Library

2009-06-17

CAPE CANAVERAL, Fla. – On Launch Complex-41 on Cape Canaveral Air Force Station in Florida, NASA's Lunar Reconnaissance Orbiter, or LRO, and NASA's Lunar Crater Observation and Sensing Satellite, known as LCROSS, and launch gantry roll out to the launch pad. They are atop their launch vehicle, the Atlas V/Centaur rocket. LRO and LCROSS are the first missions in NASA's plan to return humans to the moon and begin establishing a lunar outpost by 2020. The LRO also includes seven instruments that will help NASA characterize the moon's surface: DIVINER, LAMP, LEND, LOLA, CRATER, Mini-RF and LROC. Launch is scheduled for 5:22 p.m. EDT June 18 . Photo credit: NASA/Jack Pfaller

KSC-2009-3766

NASA Image and Video Library

2009-06-18

CAPE CANAVERAL, Fla. – With smoke and steam rolling from the launch pad, NASA's Lunar Reconnaissance Orbiter, or LRO, and NASA's Lunar Crater Observation and Sensing Satellite, known as LCROSS, lifts off from Launch Complex 41 at Cape Canaveral Air Force Station in Florida. Surrounding the pad are lightning towers. LRO and LCROSS are the first missions in NASA's plan to return humans to the moon and begin establishing a lunar outpost by 2020. The LRO also includes seven instruments that will help NASA characterize the moon's surface: DIVINER, LAMP, LEND, LOLA , CRATER, Mini-RF and LROC. Launch was on-time at 5:32 p.m. EDT June 18. Photo credit: NASA/Tom Farrar

KSC-2009-3188

NASA Image and Video Library

2009-05-15

CAPE CANAVERAL, Fla. – At Astrotech Space Operations Facility in Titusville, Fla., technicians closely watch the joining of the fairing halves around NASA's Lunar Reconnaissance Orbiter, or LRO, and and NASA's Lunar Crater Observation and Sensing Satellite, known as LCROSS. The fairing is a molded structure that fits flush with the outside surface of the rocket and forms an aerodynamically smooth nose cone, protecting the spacecraft during launch and ascent. The LRO includes five instruments: DIVINER, LAMP, LEND, LOLA and LROC. They will be launched aboard an Atlas V/Centaur rocket no earlier than June 17 from Launch Complex-41 on Cape Canaveral Air Force Station in Florida. Photo credit: NASA/Jack Pfaller

KSC-2009-3190

NASA Image and Video Library

2009-05-15

CAPE CANAVERAL, Fla. – At Astrotech Space Operations Facility in Titusville, Fla., the fairing halves are moved together for another attempt at installation around NASA's Lunar Reconnaissance Orbiter, or LRO, and NASA's Lunar Crater Observation and Sensing Satellite, known as LCROSS. The fairing is a molded structure that fits flush with the outside surface of the rocket and forms an aerodynamically smooth nose cone, protecting the spacecraft during launch and ascent. The LRO includes five instruments: DIVINER, LAMP, LEND, LOLA and LROC. They will be launched aboard an Atlas V/Centaur rocket no earlier than June 17 from Launch Complex-41 on Cape Canaveral Air Force Station in Florida. Photo credit: NASA/Jack Pfaller

KSC-2009-3184

NASA Image and Video Library

2009-05-15

CAPE CANAVERAL, Fla. – At Astrotech Space Operations Facility in Titusville, Fla., technicians move the first half of the fairing toward NASA's Lunar Reconnaissance Orbiter, or LRO, with NASA's Lunar Crater Observation and Sensing Satellite, known as LCROSS, for installation. The fairing is a molded structure that fits flush with the outside surface of the rocket and forms an aerodynamically smooth nose cone, protecting the spacecraft during launch and ascent. The LRO includes five instruments: DIVINER, LAMP, LEND, LOLA and LROC. They will be launched aboard an Atlas V/Centaur rocket no earlier than June 17 from Launch Complex-41 on Cape Canaveral Air Force Station in Florida. Photo credit: NASA/Jack Pfaller

KSC-2009-3793

NASA Image and Video Library

2009-06-18

CAPE CANAVERAL, Fla. – Smoke rolls across Launch Pad 41 at Cape Canaveral Air force Station in Florida as the Atlas V/Centaur rocket topped with NASA's Lunar Reconnaissance Orbiter, or LRO, and NASA's Lunar Crater Observation and Sensing Satellite, known as LCROSS, lifts off. Launch was on-time at 5:32 p.m. EDT June 18. LRO and LCROSS are the first missions in NASA's plan to return humans to the moon and begin establishing a lunar outpost by 2020. The LRO also includes seven instruments that will help NASA characterize the moon's surface: DIVINER, LAMP, LEND, LOLA , CRATER, Mini-RF and LROC. Photo courtesy of Scott Andrews

KSC-2009-3189

NASA Image and Video Library

2009-05-15

CAPE CANAVERAL, Fla. – At Astrotech Space Operations Facility in Titusville, Fla., the fairing halves are moved apart for another attempt at installation around NASA's Lunar Reconnaissance Orbiter, or LRO, and and NASA's Lunar Crater Observation and Sensing Satellite, known as LCROSS. The fairing is a molded structure that fits flush with the outside surface of the rocket and forms an aerodynamically smooth nose cone, protecting the spacecraft during launch and ascent. The LRO includes five instruments: DIVINER, LAMP, LEND, LOLA and LROC. They will be launched aboard an Atlas V/Centaur rocket no earlier than June 17 from Launch Complex-41 on Cape Canaveral Air Force Station in Florida. Photo credit: NASA/Jack Pfaller

KSC-2009-3740

NASA Image and Video Library

2009-06-17

CAPE CANAVERAL, Fla. – On Launch Complex-41 on Cape Canaveral Air Force Station in Florida, NASA's Lunar Reconnaissance Orbiter, or LRO, and NASA's Lunar Crater Observation and Sensing Satellite, known as LCROSS, are ready to roll out to the launch pad atop the Atlas V/Centaur rocket. LRO and LCROSS are the first missions in NASA's plan to return humans to the moon and begin establishing a lunar outpost by 2020. The LRO also includes seven instruments that will help NASA characterize the moon's surface: DIVINER, LAMP, LEND, LOLA, CRATER, Mini-RF and LROC. Launch is scheduled for 5:22 p.m. EDT June 18 . Photo credit: NASA/Jack Pfaller

KSC-2009-3781

NASA Image and Video Library

2009-06-18

CAPE CANAVERAL, Fla. – Trailing a column of fire, the Atlas V/Centaur carrying NASA's Lunar Reconnaissance Orbiter, or LRO, and NASA's Lunar Crater Observation and Sensing Satellite, known as LCROSS, hurtles off Launch Complex 41 at Cape Canaveral Air Force Station in Florida. LRO and LCROSS are the first missions in NASA's plan to return humans to the moon and begin establishing a lunar outpost by 2020. The LRO also includes seven instruments that will help NASA characterize the moon's surface: DIVINER, LAMP, LEND, LOLA , CRATER, Mini-RF and LROC. Launch was on-time at 5:32 p.m. EDT. Photo credit: NASA/Tom Farrar, Kevin O'Connell

KSC-2009-3788

NASA Image and Video Library

2009-06-18

CAPE CANAVERAL, Fla. – Lightning towers stand like guards around Launch Complex 41 at Cape Canaveral Air Force Station in Florida as the Atlas V/Centaur carrying NASA's Lunar Reconnaissance Orbiter, or LRO, and NASA's Lunar Crater Observation and Sensing Satellite, known as LCROSS, lifts off. LRO and LCROSS are the first missions in NASA's plan to return humans to the moon and begin establishing a lunar outpost by 2020. The LRO also includes seven instruments that will help NASA characterize the moon's surface: DIVINER, LAMP, LEND, LOLA , CRATER, Mini-RF and LROC. Launch was on-time at 5:32 p.m. EDT. Photo credit: NASA/Sandra Joseph, Tony Gray

KSC-2009-3185

NASA Image and Video Library

2009-05-15

CAPE CANAVERAL, Fla. – At Astrotech Space Operations Facility in Titusville, Fla., technicians observe NASA's Lunar Reconnaissance Orbiter, or LRO, with and NASA's Lunar Crater Observation and Sensing Satellite, known as LCROSS, during installation of the fairing. The fairing is a molded structure that fits flush with the outside surface of the rocket and forms an aerodynamically smooth nose cone, protecting the spacecraft during launch and ascent. The LRO includes five instruments: DIVINER, LAMP, LEND, LOLA and LROC. They will be launched aboard an Atlas V/Centaur rocket no earlier than June 17 from Launch Complex-41 on Cape Canaveral Air Force Station in Florida. Photo credit: NASA/Jack Pfaller

KSC-2009-3790

NASA Image and Video Library

2009-06-18

CAPE CANAVERAL, Fla. – On Launch Complex 41 at Cape Canaveral Air Force Station in Florida, smoke fills the pad as the Atlas V/Centaur carrying NASA's Lunar Reconnaissance Orbiter, or LRO, and NASA's Lunar Crater Observation and Sensing Satellite, known as LCROSS, lifts off. LRO and LCROSS are the first missions in NASA's plan to return humans to the moon and begin establishing a lunar outpost by 2020. The LRO also includes seven instruments that will help NASA characterize the moon's surface: DIVINER, LAMP, LEND, LOLA , CRATER, Mini-RF and LROC. Launch was on-time at 5:32 p.m. EDT. Photo credit: NASA/Sandra Joseph, Tony Gray

KSC-2009-3187

NASA Image and Video Library

2009-05-15

CAPE CANAVERAL, Fla. – At Astrotech Space Operations Facility in Titusville, Fla., technicians closely watch as the fairing halves come together around NASA's Lunar Reconnaissance Orbiter, or LRO, and and NASA's Lunar Crater Observation and Sensing Satellite, known as LCROSS. The fairing is a molded structure that fits flush with the outside surface of the rocket and forms an aerodynamically smooth nose cone, protecting the spacecraft during launch and ascent.The LRO includes five instruments: DIVINER, LAMP, LEND, LOLA and LROC. They will be launched aboard an Atlas V/Centaur rocket no earlier than June 17 from Launch Complex-41 on Cape Canaveral Air Force Station in Florida. Photo credit: NASA/Jack Pfaller

KSC-2009-3193

NASA Image and Video Library

2009-05-15

CAPE CANAVERAL, Fla. – At Astrotech Space Operations Facility in Titusville, Fla., the fairing halves have been joined to enclose NASA's Lunar Reconnaissance Orbiter, or LRO, and NASA's Lunar Crater Observation and Sensing Satellite, known as LCROSS. The fairing is a molded structure that fits flush with the outside surface of the rocket and forms an aerodynamically smooth nose cone, protecting the spacecraft during launch and ascent. The LRO includes five instruments: DIVINER, LAMP, LEND, LOLA and LROC. They will be launched aboard an Atlas V/Centaur rocket no earlier than June 17 from Launch Complex-41 on Cape Canaveral Air Force Station in Florida. Photo credit: NASA/Jack Pfaller

KSC-2009-3191

NASA Image and Video Library

2009-05-15

CAPE CANAVERAL, Fla. – At Astrotech Space Operations Facility in Titusville, Fla., technicians closely watch as the fairing halves move together to enclose NASA's Lunar Reconnaissance Orbiter, or LRO, and NASA's Lunar Crater Observation and Sensing Satellite, known as LCROSS. The fairing is a molded structure that fits flush with the outside surface of the rocket and forms an aerodynamically smooth nose cone, protecting the spacecraft during launch and ascent. The LRO includes five instruments: DIVINER, LAMP, LEND, LOLA and LROC. They will be launched aboard an Atlas V/Centaur rocket no earlier than June 17 from Launch Complex-41 on Cape Canaveral Air Force Station in Florida. Photo credit: NASA/Jack Pfaller

KSC-2009-3792

NASA Image and Video Library

2009-06-18

CAPE CANAVERAL, Fla. – The Atlas V/Centaur rocket with NASA's Lunar Reconnaissance Orbiter, or LRO, and NASA's Lunar Crater Observation and Sensing Satellite, known as LCROSS, on top leaps from Launch Pad 41 at Cape Canaveral Air force Station in Florida. Surrounding the pad are the towers that provide lightning protection. Launch was on-time at 5:32 p.m. EDT June 18. LRO and LCROSS are the first missions in NASA's plan to return humans to the moon and begin establishing a lunar outpost by 2020. The LRO also includes seven instruments that will help NASA characterize the moon's surface: DIVINER, LAMP, LEND, LOLA , CRATER, Mini-RF and LROC. Photo courtesy of Scott Andrews

KSC-2009-3783

NASA Image and Video Library

2009-06-18

CAPE CANAVERAL, Fla. – Trailing a column of fire, the Atlas V/Centaur carrying NASA's Lunar Reconnaissance Orbiter, or LRO, and NASA's Lunar Crater Observation and Sensing Satellite, known as LCROSS, hurtles off Launch Complex 41 at Cape Canaveral Air Force Station in Florida. LRO and LCROSS are the first missions in NASA's plan to return humans to the moon and begin establishing a lunar outpost by 2020. The LRO also includes seven instruments that will help NASA characterize the moon's surface: DIVINER, LAMP, LEND, LOLA , CRATER, Mini-RF and LROC. Launch was on-time at 5:32 p.m. EDT. Photo credit: NASA/Tom Farrar, Kevin O'Connell

KSC-2009-3746

NASA Image and Video Library

2009-06-17

CAPE CANAVERAL, Fla. – On Launch Complex-41 on Cape Canaveral Air Force Station in Florida, the Atlas V/Centaur rocket with NASA's Lunar Reconnaissance Orbiter, or LRO, and NASA's Lunar Crater Observation and Sensing Satellite, known as LCROSS, on top reach the launch pad. Circling the pad are the protective lightning towers. LRO and LCROSS are the first missions in NASA's plan to return humans to the moon and begin establishing a lunar outpost by 2020. The LRO also includes seven instruments that will help NASA characterize the moon's surface: DIVINER, LAMP, LEND, LOLA, CRATER, Mini-RF and LROC. Launch is scheduled for 5:22 p.m. EDT June 18 . Photo credit: NASA/Jack Pfaller

KSC-2009-3767

NASA Image and Video Library

2009-06-18

CAPE CANAVERAL, Fla. – Smoke fills the pad and trails behind the Atlas V/Centaur rocket as it roars into space carrying NASA's Lunar Reconnaissance Orbiter, or LRO, and NASA's Lunar Crater Observation and Sensing Satellite, known as LCROSS. Surrounding the pad are lightning towers. LRO and LCROSS are the first missions in NASA's plan to return humans to the moon and begin establishing a lunar outpost by 2020. The LRO also includes seven instruments that will help NASA characterize the moon's surface: DIVINER, LAMP, LEND, LOLA , CRATER, Mini-RF and LROC. Launch was on-time at 5:32 p.m. EDT June 18. Photo credit: NASA/Tom Farrar

KSC-2009-3747

NASA Image and Video Library

2009-06-17

CAPE CANAVERAL, Fla. – On Launch Complex-41 on Cape Canaveral Air Force Station in Florida, the Atlas V/Centaur rocket with NASA's Lunar Reconnaissance Orbiter, or LRO, and NASA's Lunar Crater Observation and Sensing Satellite, known as LCROSS, on top reach the launch pad. Circling the pad are the protective lightning towers. LRO and LCROSS are the first missions in NASA's plan to return humans to the moon and begin establishing a lunar outpost by 2020. The LRO also includes seven instruments that will help NASA characterize the moon's surface: DIVINER, LAMP, LEND, LOLA, CRATER, Mini-RF and LROC. Launch is scheduled for 5:22 p.m. EDT June 18 . Photo credit: NASA/Jack Pfaller

Americas from the Moon

NASA Image and Video Library

2010-09-15

The western hemisphere of our home planet Earth. North (upper left), Central, and South America (lower right) were nicely free of clouds when LRO pointed home on 9 August 2010 to acquire this beautiful view. LROC NAC E136013771. As LRO orbits the Moon every two hours sending down a stream of science data, it is easy to forget how close the Moon is to the Earth. The average distance between the two heavenly bodies is just 384,399 km (238,854 miles). Check your airline frequent flyer totals, perhaps you have already flown the distance to the Moon and back on a single airline. http://photojournal.jpl.nasa.gov/catalog/PIA13519

MACS-Himalaya: A photogrammetric aerial oblique camera system designed for highly accurate 3D-reconstruction and monitoring in steep terrain and under extreme illumination conditions

NASA Astrophysics Data System (ADS)

Brauchle, Joerg; Berger, Ralf; Hein, Daniel; Bucher, Tilman

2017-04-01

The DLR Institute of Optical Sensor Systems has developed the MACS-Himalaya, a custom built Modular Aerial Camera System specifically designed for the extreme geometric (steep slopes) and radiometric (high contrast) conditions of high mountain areas. It has an overall field of view of 116° across-track consisting of a nadir and two oblique looking RGB camera heads and a fourth nadir looking near-infrared camera. This design provides the capability to fly along narrow valleys and simultaneously cover ground and steep valley flank topography with similar ground resolution. To compensate for extreme contrasts between fresh snow and dark shadows in high altitudes a High Dynamic Range (HDR) mode was implemented, which typically takes a sequence of 3 images with graded integration times, each covering 12 bit radiometric depth, resulting in a total dynamic range of 15-16 bit. This enables dense image matching and interpretation for sunlit snow and glaciers as well as for dark shaded rock faces in the same scene. Small and lightweight industrial grade camera heads are used and operated at a rate of 3.3 frames per second with 3-step HDR, which is sufficient to achieve a longitudinal overlap of approximately 90% per exposure time at 1,000 m above ground at a velocity of 180 km/h. Direct georeferencing and multitemporal monitoring without the need of ground control points is possible due to the use of a high end GPS/INS system, a stable calibrated inner geometry of the camera heads and a fully photogrammetric workflow at DLR. In 2014 a survey was performed on the Nepalese side of the Himalayas. The remote sensing system was carried in a wingpod by a Stemme S10 motor glider. Amongst other targets, the Seti Valley, Kali-Gandaki Valley and the Mt. Everest/Khumbu Region were imaged at altitudes up to 9,200 m. Products such as dense point clouds, DSMs and true orthomosaics with a ground pixel resolution of up to 15 cm were produced in regions and outcrops normally inaccessible to aerial imagery. These data are used in the fields of natural hazards, geomorphology and glaciology (see Thompson et al., CR4.3). In the presentation the camera system is introduced and examples and applications from the Nepal campaign are given.

Ortho-Rectification of Narrow Band Multi-Spectral Imagery Assisted by Dslr RGB Imagery Acquired by a Fixed-Wing Uas

NASA Astrophysics Data System (ADS)

Rau, J.-Y.; Jhan, J.-P.; Huang, C.-Y.

2015-08-01

Miniature Multiple Camera Array (MiniMCA-12) is a frame-based multilens/multispectral sensor composed of 12 lenses with narrow band filters. Due to its small size and light weight, it is suitable to mount on an Unmanned Aerial System (UAS) for acquiring high spectral, spatial and temporal resolution imagery used in various remote sensing applications. However, due to its wavelength range is only 10 nm that results in low image resolution and signal-to-noise ratio which are not suitable for image matching and digital surface model (DSM) generation. In the meantime, the spectral correlation among all 12 bands of MiniMCA images are low, it is difficult to perform tie-point matching and aerial triangulation at the same time. In this study, we thus propose the use of a DSLR camera to assist automatic aerial triangulation of MiniMCA-12 imagery and to produce higher spatial resolution DSM for MiniMCA12 ortho-image generation. Depending on the maximum payload weight of the used UAS, these two kinds of sensors could be collected at the same time or individually. In this study, we adopt a fixed-wing UAS to carry a Canon EOS 5D Mark2 DSLR camera and a MiniMCA-12 multi-spectral camera. For the purpose to perform automatic aerial triangulation between a DSLR camera and the MiniMCA-12, we choose one master band from MiniMCA-12 whose spectral range has overlap with the DSLR camera. However, all lenses of MiniMCA-12 have different perspective centers and viewing angles, the original 12 channels have significant band misregistration effect. Thus, the first issue encountered is to reduce the band misregistration effect. Due to all 12 MiniMCA lenses being frame-based, their spatial offsets are smaller than 15 cm and all images are almost 98% overlapped, we thus propose a modified projective transformation (MPT) method together with two systematic error correction procedures to register all 12 bands of imagery on the same image space. It means that those 12 bands of images acquired at the same exposure time will have same interior orientation parameters (IOPs) and exterior orientation parameters (EOPs) after band-to-band registration (BBR). Thus, in the aerial triangulation stage, the master band of MiniMCA-12 was treated as a reference channel to link with DSLR RGB images. It means, all reference images from the master band of MiniMCA-12 and all RGB images were triangulated at the same time with same coordinate system of ground control points (GCP). Due to the spatial resolution of RGB images is higher than the MiniMCA-12, the GCP can be marked on the RGB images only even they cannot be recognized on the MiniMCA images. Furthermore, a one meter gridded digital surface model (DSM) is created by the RGB images and applied to the MiniMCA imagery for ortho-rectification. Quantitative error analyses show that the proposed BBR scheme can achieve 0.33 pixels of average misregistration residuals length and the co-registration errors among 12 MiniMCA ortho-images and between MiniMCA and Canon RGB ortho-images are all less than 0.6 pixels. The experimental results demonstrate that the proposed method is robust, reliable and accurate for future remote sensing applications.

High-angular-resolution NIR astronomy with large arrays (SHARP I and SHARP II)

NASA Astrophysics Data System (ADS)

Hofmann, Reiner; Brandl, Bernhard; Eckart, Andreas; Eisenhauer, Frank; Tacconi-Garman, Lowell E.

1995-06-01

SHARP I and SHARP II are near infrared cameras for high-angular-resolution imaging. Both cameras are built around a 256 X 256 pixel NICMOS 3 HgCdTe array from Rockwell which is sensitive in the 1 - 2.5 micrometers range. With a 0.05'/pixel scale, they can produce diffraction limited K-band images at 4-m-class telescopes. For a 256 X 256 array, this pixel scale results in a field of view of 12.8' X 12.8' which is well suited for the observation of galactic and extragalactic near-infrared sources. Photometric and low resolution spectroscopic capabilities are added by photometric band filters (J, H, K), narrow band filters ((lambda) /(Delta) (lambda) approximately equals 100) for selected spectral lines, and a CVF ((lambda) /(Delta) (lambda) approximately equals 70). A cold shutter permits short exposure times down to about 10 ms. The data acquisition electronics permanently accepts the maximum frame rate of 8 Hz which is defined by the detector time constants (data rate 1 Mbyte/s). SHARP I has been especially designed for speckle observations at ESO's 3.5 m New Technology Telescope and is in operation since 1991. SHARP II is used at ESO's 3.6 m telescope together with the adaptive optics system COME-ON + since 1993. A new version of SHARP II is presently under test, which incorporates exchangeable camera optics for observations with scales of 0.035, 0.05, and 0.1'/pixel. The first scale extends diffraction limited observations down to the J-band, while the last one provides a larger field of view. To demonstrate the power of the cameras, images of the galactic center obtained with SHARP I, and images of the R136 region in 30 Doradus observed with SHARP II are presented.

3D Modeling from Multi-views Images for Cultural Heritage in Wat-Pho, Thailand

NASA Astrophysics Data System (ADS)

Soontranon, N.; Srestasathiern, P.; Lawawirojwong, S.

2015-08-01

In Thailand, there are several types of (tangible) cultural heritages. This work focuses on 3D modeling of the heritage objects from multi-views images. The images are acquired by using a DSLR camera which costs around 1,500 (camera and lens). Comparing with a 3D laser scanner, the camera is cheaper and lighter than the 3D scanner. Hence, the camera is available for public users and convenient for accessing narrow areas. The acquired images consist of various sculptures and architectures in Wat-Pho which is a Buddhist temple located behind the Grand Palace (Bangkok, Thailand). Wat-Pho is known as temple of the reclining Buddha and the birthplace of traditional Thai massage. To compute the 3D models, a diagram is separated into following steps; Data acquisition, Image matching, Image calibration and orientation, Dense matching and Point cloud processing. For the initial work, small heritages less than 3 meters height are considered for the experimental results. A set of multi-views images of an interested object is used as input data for 3D modeling. In our experiments, 3D models are obtained from MICMAC (open source) software developed by IGN, France. The output of 3D models will be represented by using standard formats of 3D point clouds and triangulated surfaces such as .ply, .off, .obj, etc. To compute for the efficient 3D models, post-processing techniques are required for the final results e.g. noise reduction, surface simplification and reconstruction. The reconstructed 3D models can be provided for public access such as website, DVD, printed materials. The high accurate 3D models can also be used as reference data of the heritage objects that must be restored due to deterioration of a lifetime, natural disasters, etc.

Photogrammetric application of viking orbital photography

USGS Publications Warehouse

Wu, S.S.C.; Elassal, A.A.; Jordan, R.; Schafer, F.J.

1982-01-01

Special techniques are described for the photogrammetric compilation of topographic maps and profiles from stereoscopic photographs taken by the two Viking Orbiter spacecraft. These techniques were developed because the extremely narrow field of view of the Viking cameras precludes compilation by conventional photogrammetric methods. The techniques adjust for internal consistency the Supplementary Experiment Data Record (SEDR-the record of spacecraft orientation when photographs were taken) and the computation of geometric orientation parameters of the stereo models. A series of contour maps of Mars is being compiled by these new methods using a wide variety of Viking Orbiter photographs, to provide the planetary research community with topographic information. ?? 1982.

ARC-1986-A86-7010

NASA Image and Video Library

1986-01-22

Range : 2.52 million miles (1.56 million miles) Resolution : 47km. ( 29 mi.) Closest Approach: 127,000 km. (79,000 mi.) P-29479B/W This Voyager 2 image of the brightest Uranian satellite of the five largest, Ariel, was shot through a clear filter with the narrow angle camera. Ariel is about 1,300 km. ( 800 mi. )in diameter. This image shows several distinct bright areas that reflect nearly 45 % of the incident sunlight. On average, the satellite displays reflectivity of about 25-30 %. The bright areas are probably fresh water ice, perhaps excavated by impacts. the south pole of Ariel is slightly off center of the disk in this view.

Modeling of the Terminal Velocities of the Dust Ejected Material by the Impact

NASA Astrophysics Data System (ADS)

Rengel, M.; Küppers, M.; Keller, H. U.; Gutiérrez, P.

We compute the distribution of velocities of the particles ejected by the impact of the projectile released from NASA Deep Impact spacecraft on the nucleus of comet 9P/Tempel 1 on the successive 20 h following the collision. This is performed by the development and use of an ill-conditioned inverse problem approach, whose main ingredients are a set of observations taken by the Narrow Angle Camera (NAC) of OSIRIS onboard the Rosetta spacecraft, and a set of simple models of the expansion of the dust ejecta plume for different velocities. Terminal velocities are derived using a maximum likelihood estimator.

Coastal Asia as seen from the ISS

NASA Image and Video Library

2001-03-30

ISS01-E-5082 (December 2000) --- This image of coastal Asia was taken from the International Space Station with a digital still camera and a 400mm lens with a very narrow field of view. Early in the Space Station Program, communications with the crew are less direct, and the exact time that this image was taken could not be determined. Because there are relatively few photograph of Earth taken with this long lens, and because the times are not available to calculate the exact position of the Station over the Earth when the photograph was taken, the exact location of the photograph cannot be determined. Many of these logistical problems will be resolved as camera equipment is replaced and communications with the crew improve. Catalogers believe the coast most resembles Indonesia, and this determination will be maintained until future images allow correction and refinement of the location. The photograph is a striking example of the degree to which humans modify coastal environments. The large green squares in the image probably represent a combination of rice cultivation and aquaculture.

ARC-1989-AC89-7001

NASA Image and Video Library

1989-08-21

Photo by Voyager 2 (JPL) During August 16 and 17, 1989, the Voyager 2 narrow-angle camera was used to photograph Neptune almost continuously, recording approximately two and one-half rotations of the planet. These images represent the most complete set of full disk Neptune images that the spacecraft will acquire. This picture from the sequence shows two of the four cloud features which have been tracked by the Voyager cameras during the past two months. The large dark oval near the western limb (the left edge) is at a latitude of 22 degrees south and circuits Neptune every 18.3 hours. The bright clouds immediately to the south and east of this oval are seen to substantially change their appearances in periods as short as four hours. The second dark spot, at 54 degrees south latitude near the terminator (lower right edge), circuits Neptune every 16.1 hours. This image has been processed to enchance the visibility of small features, at some sacrifice of color fidelity. The Voyager Mission is conducted by JPL for NASA's Office of Space Science and Applications. (JPL Ref: A-34611 Voyager 2-N29)

Automatic Generation of Wide Dynamic Range Image without Pseudo-Edge Using Integration of Multi-Steps Exposure Images

NASA Astrophysics Data System (ADS)

Migiyama, Go; Sugimura, Atsuhiko; Osa, Atsushi; Miike, Hidetoshi

Recently, digital cameras are offering technical advantages rapidly. However, the shot image is different from the sight image generated when that scenery is seen with the naked eye. There are blown-out highlights and crushed blacks in the image that photographed the scenery of wide dynamic range. The problems are hardly generated in the sight image. These are contributory cause of difference between the shot image and the sight image. Blown-out highlights and crushed blacks are caused by the difference of dynamic range between the image sensor installed in a digital camera such as CCD and CMOS and the human visual system. Dynamic range of the shot image is narrower than dynamic range of the sight image. In order to solve the problem, we propose an automatic method to decide an effective exposure range in superposition of edges. We integrate multi-step exposure images using the method. In addition, we try to erase pseudo-edges using the process to blend exposure values. Afterwards, we get a pseudo wide dynamic range image automatically.

Visualization of hump formation in high-speed gas metal arc welding

NASA Astrophysics Data System (ADS)

Wu, C. S.; Zhong, L. M.; Gao, J. Q.

2009-11-01

The hump bead is a typical weld defect observed in high-speed welding. Its occurrence limits the improvement of welding productivity. Visualization of hump formation during high-speed gas metal arc welding (GMAW) is helpful in the better understanding of the humping phenomena so that effective measures can be taken to suppress or decrease the tendency of hump formation and achieve higher productivity welding. In this study, an experimental system was developed to implement vision-based observation of the weld pool behavior during high-speed GMAW. Considering the weld pool characteristics in high-speed welding, a narrow band-pass and neutral density filter was equipped for the CCD camera, the suitable exposure time was selected and side view orientation of the CCD camera was employed. The events that took place at the rear portion of the weld pools were imaged during the welding processes with and without hump bead formation, respectively. It was found that the variation of the weld pool surface height and the solid-liquid interface at the pool trailing with time shows some useful information to judge whether the humping phenomenon occurs or not.

Lakes Through the Haze

NASA Image and Video Library

2013-12-23

Using a special spectral filter, the high-resolution camera aboard NASA's Cassini spacecraft was able to peer through the hazy atmosphere of Saturn's moon Titan. It captured this image, which features the largest seas and some of the many hydrocarbon lakes that are present on Titan's surface. Titan is the only place in the solar system, other than Earth, that has stable liquids on its surface. In this case, the liquid consists of ethane and methane rather than water. This view looks towards the side of Titan (3,200 miles or 5,150 kilometers across) that leads in its orbit around Saturn. North on Titan is up and rotated 36 degrees to the left. Images taken using red, green and blue spectral filters were combined to create this natural-color view. The images were taken with the Cassini spacecraft narrow-angle camera on Oct. 7, 2013. The view was acquired at a distance of approximately 809,000 miles (1.303 million kilometers) from Titan. Image scale is 5 miles (8 kilometers) per pixel. http://photojournal.jpl.nasa.gov/catalog/PIA17179

Aspects of Voyager photogrammetry

NASA Technical Reports Server (NTRS)

Wu, Sherman S. C.; Schafer, Francis J.; Jordan, Raymond; Howington, Annie-Elpis

1987-01-01

In January 1986, Voyager 2 took a series of pictures of Uranus and its satellites with the Imaging Science System (ISS) on board the spacecraft. Based on six stereo images from the ISS narrow-angle camera, a topographic map was compiled of the Southern Hemisphere of Miranda, one of Uranus' moons. Assuming a spherical figure, a 20-km surface relief is shown on the map. With three additional images from the ISS wide-angle camera, a control network of Miranda's Southern Hemisphere was established by analytical photogrammetry, producing 88 ground points for the control of multiple-model compilation on the AS-11AM analytical stereoplotter. Digital terrain data from the topographic map of Miranda have also been produced. By combining these data and the image data from the Voyager 2 mission, perspective views or even a movie of the mapped area can be made. The application of these newly developed techniques to Voyager 1 imagery, which includes a few overlapping pictures of Io and Ganymede, permits the compilation of contour maps or topographic profiles of these bodies on the analytical stereoplotters.

Autonomous Navigation by a Mobile Robot

NASA Technical Reports Server (NTRS)

Huntsberger, Terrance; Aghazarian, Hrand

2005-01-01

ROAMAN is a computer program for autonomous navigation of a mobile robot on a long (as much as hundreds of meters) traversal of terrain. Developed for use aboard a robotic vehicle (rover) exploring the surface of a remote planet, ROAMAN could also be adapted to similar use on terrestrial mobile robots. ROAMAN implements a combination of algorithms for (1) long-range path planning based on images acquired by mast-mounted, wide-baseline stereoscopic cameras, and (2) local path planning based on images acquired by body-mounted, narrow-baseline stereoscopic cameras. The long-range path-planning algorithm autonomously generates a series of waypoints that are passed to the local path-planning algorithm, which plans obstacle-avoiding legs between the waypoints. Both the long- and short-range algorithms use an occupancy-grid representation in computations to detect obstacles and plan paths. Maps that are maintained by the long- and short-range portions of the software are not shared because substantial localization errors can accumulate during any long traverse. ROAMAN is not guaranteed to generate an optimal shortest path, but does maintain the safety of the rover.

The Activity of Comet 67P/Churyumov-Gerasimenko as Seen by Rosetta/OSIRIS

NASA Astrophysics Data System (ADS)

Sierks, H.; Barbieri, C.; Lamy, P. L.; Rodrigo, R.; Rickman, H.; Koschny, D.

2015-12-01

The Rosetta mission of the European Space Agency arrived on August 6, 2014, at the target comet 67P/Churyumov-Gerasimenko. OSIRIS (Optical, Spectroscopic, and Infrared Remote Imaging System) is the scientific imaging system onboard Rosetta. OSIRIS consists of a Narrow Angle Camera (NAC) for the nucleus surface and dust studies and a Wide Angle Camera (WAC) for the wide field gas and dust coma investigations. OSIRIS observed the coma and the nucleus of comet 67P/C-G during approach, arrival, and landing of PHILAE. OSIRIS continued comet monitoring and mapping of surface and activity in 2015 with close fly-bys with high resolution and remote, wide angle observations. The scientific results reveal a nucleus with two lobes and varied morphology. Active regions are located at steep cliffs and collapsed pits which form collimated gas jets. Dust is accelerated by the gas, forming bright jet filaments and the large scale, diffuse coma of the comet. We will present activity and surface changes observed in the Northern and Southern hemisphere and around perihelion passage.

Lunar cryptomare: Analysis of mineralogy and distribution of ancient volcanic deposits

NASA Astrophysics Data System (ADS)

Whitten, J.; Head, J. W.; Pieters, C. M.; Kreslavsky, M. A.; Hiesinger, H.

2012-12-01

Early volcanic deposits have been almost completely erased by plate tectonics on Earth, but they remain relatively well preserved on some of the other terrestrial planetary bodies, especially the Moon. Ancient volcanic smooth plains on the Moon are referred to as cryptomaria [Head and Wilson, 1992], described as smooth volcanic deposits that have been covered post-emplacement with high albedo feldspathic regolith. Identification of cryptomare deposits is facilitated by the presence of dark-halo craters, which are typically simple craters excavating mafic material from below the feldspathic light plains regolith layer [e.g., Schultz and Spudis, 1979], and highly mafic soils. Isotopic age data from the Apollo and lunar meteorite sample collections combined with crater statistics and stratigraphic relationships indicate that cryptomare deposits were emplaced around the period of latest basin formation. Many questions about cryptomare deposits remain: Were they emplaced in ancient lunar basins or are they associated with intercrater areas? What is their areal extent? What is the mineralogy of these deposits? Does it vary spatially or temporally? Analysis with the highest resolution datasets could address several of these questions and help to refine our knowledge of the extent and character of early lunar volcanism. For this study cryptomare to the west of Oceanus Procellarum, as well as other previously identified regions (e.g., Mendel-Ryberg, Tsiolkovskiy, etc.), were selected for analysis based on their different geologic settings. To better understand early eruption conditions it is important to compare deposit locations and look for trends in geologic setting. Analysis of previously mapped cryptomare in the Schiller-Schickard region has established a method for deposit identification and is applied in this study to map and characterize the composition of the early volcanic deposits in other areas of the Moon [Whitten et al., 2012]. Lunar Orbiter Laser Altimeter (LOLA) data are being used to understand the geologic context and surface roughness of these ancient volcanic deposits and Lunar Reconnaissance Orbiter Camera (LROC) image data are used to identify the exposure of lower albedo material or small dark-halo craters and also to help narrow down the boundary of the cryptomare deposits. In addition to topographic and image data, mineralogy data from the Moon Mineralogy Mapper (M3) instrument are being used to identify cryptomare deposits and to measure the compositional variability of the exposed mafic regions in these deposits. The measured mineral compositions of cryptomare deposits from dark-halo craters are compared with spectra collected from exposed mare deposits to determine if there are observable compositional differences. Our analyses support previous interpretations in the Schiller-Schickard region that suggest that the composition of volcanic deposits did not changed significantly during the ≥100 Ma of volcanic activity and that at least some of the cryptomare deposits in the region were emplaced in the Schiller-Zucchius basin. References Head, J.W. and L. Wilson, (1992) GCA, 55, 2155-2175. Schultz, P.H. and P.D. Spudis, (1079) Proc. Lunar Planet. Sci. Conf., 10th, 2899-2918. Whitten, J.L., J.W. Head, C.M. Pieters and H. Hiesinger, (2012) Lunar Sci. Forum, Abstract #592.

Shallow Lunar Seismic Activity and the Current Stress State of the Moon

NASA Technical Reports Server (NTRS)

Watters, T. R.; Weber, R. C.; Collins, G. C.; Johnson, C. L.

2017-01-01

A vast, global network of more than 3200 lobate thrust fault scarps has been revealed in high resolution Lunar Reconnaissance Orbiter Camera (LROC) images. The fault scarps very young, less than 50 Ma, based on their small scale and crisp appearance, crosscutting relations with small-diameter impact craters, and rates of infilling of associated small, shallow graben and may be actively forming today. The population of young thrust fault scarps provides a window into the recent stress state of the Moon and offers insight into the origin of global lunar stresses. The distribution of orientations of the fault scarps is non-random, inconsistent with isotropic stresses from late-stage global contraction as the sole source of stress Modeling shows that tidal stresses contribute significantly to the current stress state of the lunar crust. Tidal stresses (orbital recession and diurnal tides) superimposed on stresses from global contraction result in non-isotropic compressional stress and thrust faults consistent with lobate scarp orientations. Stresses due to orbital recession do not change with orbital position, thus it is with the addition of diurnal stresses that peak stresses are reached. At apogee, diurnal and recession stresses are most compressive near the tidal axis, while at perigee they are most compressive 90 degrees away from the tidal axis. Coseismic slip events on currently active thrust faults are expected to be triggered when peak stresses are reached. Analysis of the timing of the 28 the shallow moonquakes recorded by the Apollo seismic network shows that 19 indeed occur when the Moon is closer to apogee, while only 9 shallow events occur when the Moon is closer to perigee. Here we show the results of relocating the shallow moonquake using an algorithm designed for sparse networks to better constrain their epicentral locations in order to compare them with stress models. The model for the current stress state of the Moon is refined by investigating the contribution of polar wander.

Mineralogy and chemistry of Ti-bearing lunar soils: Effects on reflectance spectra and remote sensing observations

NASA Astrophysics Data System (ADS)

Coman, Ecaterina O.; Jolliff, Bradley L.; Carpenter, Paul

2018-05-01

This paper presents results of coordinated ultraviolet and visible wavelength reflectance measurements, X-ray diffraction analyses of mineral components, and micro X-ray fluorescence analyses of Ti concentrations of 13 lunar soil samples (<210 μm) that span a range of maturity and TiO2 contents. Results of these analyses are used to determine the effects of soil maturity, TiO2 concentration, and specific mineralogical makeup, especially ilmenite content, on the ultraviolet/visible (UV/VIS) ratio for application to remote sensing observations of the Moon and other airless bodies. We find that measured ilmenite weight percent correlates highly with measured TiO2 concentrations. Thus, the ilmenite content is a good predictor of TiO2 concentration. Ilmenite is the main contributor of TiO2 for soils with greater than about 2 wt.% TiO2, so we take the effects of TiO2 on reflectance spectra to be essentially those of ilmenite. Constraining the data set to eight mature Apollo soils, we find that among the UV/VIS ratios from laboratory-measured spectra, the 321/415 nm ratio shows the best correlation with TiO2 and ilmenite. Moreover, for soils with similar maturity in the submature to mature range, those with higher TiO2 have higher 321/415 UV/VIS ratios. Finally, the correlation between TiO2 content and 321/415 ratio in samples measured in the lab appears weaker than for the same relationship using the Lunar Reconnaissance Orbiter (LRO) Wide Angle Camera (WAC) spectral data for the 321/415 ratio of Apollo ground-truth sites. The correlation between lab-derived 321/415 ratios and TiO2 content for measured samples improves when low-maturity samples are excluded from the dataset, implying that the LROC WAC spectra at 400 m/pix spatial resolution senses mostly mature soil.

KSC-2009-3778

NASA Image and Video Library

2009-06-18

CAPE CANAVERAL, Fla. – Smoke pours across Launch Complex 41 at Cape Canaveral Air Force Station in Florida as the Atlas V/Centaur carrying NASA's Lunar Reconnaissance Orbiter, or LRO, and NASA's Lunar Crater Observation and Sensing Satellite, known as LCROSS, roars into the sky. The towers around the pad are part of the lightning protection system. LRO and LCROSS are the first missions in NASA's plan to return humans to the moon and begin establishing a lunar outpost by 2020. The LRO also includes seven instruments that will help NASA characterize the moon's surface: DIVINER, LAMP, LEND, LOLA , CRATER, Mini-RF and LROC. Launch was on-time at 5:32 p.m. EDT. Photo credit: NASA/Tom Farrar, Kevin O'Connell

KSC-2009-3774

NASA Image and Video Library

2009-06-18

CAPE CANAVERAL, Fla. – On Launch Complex 41 at Cape Canaveral Air Force Station in Florida, bursts of smoke and steam signal liftoff for the Atlas V/Centaur rocket carrying NASA's Lunar Reconnaissance Orbiter, or LRO, and NASA's Lunar Crater Observation and Sensing Satellite, known as LCROSS, toward space. Surrounding the pad are lightning towers. LRO and LCROSS are the first missions in NASA's plan to return humans to the moon and begin establishing a lunar outpost by 2020. The LRO also includes seven instruments that will help NASA characterize the moon's surface: DIVINER, LAMP, LEND, LOLA , CRATER, Mini-RF and LROC. Launch was on-time at 5:32 p.m. EDT June 18. Photo credit: NASA/Jeffery Marino

KSC-2009-3775

NASA Image and Video Library

2009-06-18

CAPE CANAVERAL, Fla. – The Atlas V/Centaur rocket carrying NASA's Lunar Reconnaissance Orbiter, or LRO, and NASA's Lunar Crater Observation and Sensing Satellite, known as LCROSS, leaps into the sky with a tail of smoke behind as it lifts off from Launch Complex 41 at Cape Canaveral Air Force Station in Florida. Surrounding the pad below are lightning towers. LRO and LCROSS are the first missions in NASA's plan to return humans to the moon and begin establishing a lunar outpost by 2020. The LRO also includes seven instruments that will help NASA characterize the moon's surface: DIVINER, LAMP, LEND, LOLA , CRATER, Mini-RF and LROC. Launch was on-time at 5:32 p.m. EDT June 18. Photo credit: NASA/Jeffery Marino

KSC-2009-3183

NASA Image and Video Library

2009-05-15

CAPE CANAVERAL, Fla. – At Astrotech Space Operations Facility in Titusville, Fla., NASA's Lunar Reconnaissance Orbiter, or LRO, and NASA's Lunar Crater Observation and Sensing Satellite, known as LCROSS,wait for fairing installation. The fairing halves are on left and right of the spacecraft. The fairing is a molded structure that fits flush with the outside surface of the rocket and forms an aerodynamically smooth nose cone, protecting the spacecraft during launch and ascent. The LRO includes five instruments: DIVINER, LAMP, LEND, LOLA and LROC. They will be launched aboard an Atlas V/Centaur rocket no earlier than June 17 from Launch Complex-41 on Cape Canaveral Air Force Station in Florida. Photo credit: NASA/Jack Pfaller

KSC-2009-3779

NASA Image and Video Library

2009-06-18

CAPE CANAVERAL, Fla. – Fire signals liftoff of the Atlas V/Centaur carrying NASA's Lunar Reconnaissance Orbiter, or LRO, and NASA's Lunar Crater Observation and Sensing Satellite, known as LCROSS, from Launch Complex 41 at Cape Canaveral Air Force Station in Florida. The tower at left is part of the lightning protection system on the pad. LRO and LCROSS are the first missions in NASA's plan to return humans to the moon and begin establishing a lunar outpost by 2020. The LRO also includes seven instruments that will help NASA characterize the moon's surface: DIVINER, LAMP, LEND, LOLA , CRATER, Mini-RF and LROC. Launch was on-time at 5:32 p.m. EDT. Photo credit: NASA/Tom Farrar, Kevin O'Connell

KSC-2009-3769

NASA Image and Video Library

2009-06-18

CAPE CANAVERAL, Fla. – Smoke and steam roll across the launch pad as NASA's Lunar Reconnaissance Orbiter, or LRO, and NASA's Lunar Crater Observation and Sensing Satellite, known as LCROSS, lifts off atop the Atlas V/Centaur rocket from Launch Complex 41 at Cape Canaveral Air Force Station in Florida. Surrounding the pad are lightning towers. LRO and LCROSS are the first missions in NASA's plan to return humans to the moon and begin establishing a lunar outpost by 2020. The LRO also includes seven instruments that will help NASA characterize the moon's surface: DIVINER, LAMP, LEND, LOLA , CRATER, Mini-RF and LROC. Launch was on-time at 5:32 p.m. EDT June 18. Photo credit: NASA/Kim Shiflett

KSC-2009-3784

NASA Image and Video Library

2009-06-18

CAPE CANAVERAL, Fla. – Smoke pours across Launch Complex 41 at Cape Canaveral Air Force Station in Florida as the Atlas V/Centaur carrying NASA's Lunar Reconnaissance Orbiter, or LRO, and NASA's Lunar Crater Observation and Sensing Satellite, known as LCROSS, roars into the sky. The towers around the pad are part of the lightning protection system. LRO and LCROSS are the first missions in NASA's plan to return humans to the moon and begin establishing a lunar outpost by 2020. The LRO also includes seven instruments that will help NASA characterize the moon's surface: DIVINER, LAMP, LEND, LOLA , CRATER, Mini-RF and LROC. Launch was on-time at 5:32 p.m. EDT. Photo credit: NASA/Tom Farrar, Kevin O'Connell

KSC-2009-3754

NASA Image and Video Library

2009-06-18

CAPE CANAVERAL, Fla. – Photographer Joel Powell, with Spaceflight Magazine, captures a closeup of NASA's Lunar Reconnaissance Orbiter, or LRO, and NASA's Lunar Crater Observation and Sensing Satellite, known as LCROSS, atop the Atlas V/Centaur rocket on Launch Pad 41 at Cape Canaveral Air Force Station in Florida. Around the pad are the lightning towers. LRO and LCROSS are the first missions in NASA's plan to return humans to the moon and begin establishing a lunar outpost by 2020. The LRO also includes seven instruments that will help NASA characterize the moon's surface: DIVINER, LAMP, LEND, LOLA , CRATER, Mini-RF and LROC. Launch is scheduled for 5:12 p.m. EDT June 18. Photo credit: NASA/Ken Thornsley

KSC-2009-3745

NASA Image and Video Library

2009-06-17

CAPE CANAVERAL, Fla. – On Launch Complex-41 on Cape Canaveral Air Force Station in Florida, the Atlas V/Centaur rocket with NASA's Lunar Reconnaissance Orbiter, or LRO, and NASA's Lunar Crater Observation and Sensing Satellite, known as LCROSS, on top roll out to the launch pad. At right are the protective lightning towers that surround the pad. LRO and LCROSS are the first missions in NASA's plan to return humans to the moon and begin establishing a lunar outpost by 2020. The LRO also includes seven instruments that will help NASA characterize the moon's surface: DIVINER, LAMP, LEND, LOLA, CRATER, Mini-RF and LROC. Launch is scheduled for 5:22 p.m. EDT June 18 . Photo credit: NASA/Jack Pfaller

KSC-2009-3773

NASA Image and Video Library

2009-06-18

CAPE CANAVERAL, Fla. – On Launch Complex 41 at Cape Canaveral Air Force Station in Florida, bursts of smoke and steam signal liftoff for the Atlas V/Centaur rocket carrying NASA's Lunar Reconnaissance Orbiter, or LRO, and NASA's Lunar Crater Observation and Sensing Satellite, known as LCROSS, toward space. Surrounding the pad are lightning towers. LRO and LCROSS are the first missions in NASA's plan to return humans to the moon and begin establishing a lunar outpost by 2020. The LRO also includes seven instruments that will help NASA characterize the moon's surface: DIVINER, LAMP, LEND, LOLA , CRATER, Mini-RF and LROC. Launch was on-time at 5:32 p.m. EDT June 18. Photo credit: NASA/Jeffery Marino

KSC-2009-3768

NASA Image and Video Library

2009-06-18

CAPE CANAVERAL, Fla. – Smoke and steam roll across the launch pad as NASA's Lunar Reconnaissance Orbiter, or LRO, and NASA's Lunar Crater Observation and Sensing Satellite, known as LCROSS, lifts off atop the Atlas V/Centaur rocket from Launch Complex 41 at Cape Canaveral Air Force Station in Florida. Surrounding the pad are lightning towers. LRO and LCROSS are the first missions in NASA's plan to return humans to the moon and begin establishing a lunar outpost by 2020. The LRO also includes seven instruments that will help NASA characterize the moon's surface: DIVINER, LAMP, LEND, LOLA , CRATER, Mini-RF and LROC. Launch was on-time at 5:32 p.m. EDT June 18. Photo credit: NASA/Kim Shiflett

Morphometric analysis of a fresh simple crater on the Moon.

NASA Astrophysics Data System (ADS)

Vivaldi, V.; Ninfo, A.; Massironi, M.; Martellato, E.; Cremonese, G.

In this research we are proposing an innovative method to determine and quantify the morphology of a simple fresh impact crater. Linné is a well preserved impact crater of 2.2 km in diameter, located at 27.7oN 11.8oE, near the western edge of Mare Serenitatis on the Moon. The crater was photographed by the Lunar Orbiter and the Apollo space missions. Its particular morphology may place Linné as the most striking example of small fresh simple crater. Morphometric analysis, conducted on recent high resolution DTM from LROC (NASA), quantitatively confirmed the pristine morphology of the crater, revealing a clear inner layering which highlight a sequence of lava emplacement events.

KSC-2009-3771

NASA Image and Video Library

2009-06-18

CAPE CANAVERAL, Fla. – Viewed across the Indian River Lagoon, the Atlas V/Centaur rocket carrying NASA's Lunar Reconnaissance Orbiter, or LRO, and NASA's Lunar Crater Observation and Sensing Satellite, known as LCROSS, lifts off from Launch Complex 41 at Cape Canaveral Air Force Station in Florida. Surrounding the pad are lightning towers. LRO and LCROSS are the first missions in NASA's plan to return humans to the moon and begin establishing a lunar outpost by 2020. The LRO also includes seven instruments that will help NASA characterize the moon's surface: DIVINER, LAMP, LEND, LOLA , CRATER, Mini-RF and LROC. Launch was on-time at 5:32 p.m. EDT June 18. Photo credit: NASA/Tony Gray

KSC-2009-3770

NASA Image and Video Library

2009-06-18

CAPE CANAVERAL, Fla. – Viewed across the Indian River Lagoon, the Atlas V/Centaur rocket carrying NASA's Lunar Reconnaissance Orbiter, or LRO, and NASA's Lunar Crater Observation and Sensing Satellite, known as LCROSS, lifts off from Launch Complex 41 at Cape Canaveral Air Force Station in Florida. Surrounding the pad are lightning towers. LRO and LCROSS are the first missions in NASA's plan to return humans to the moon and begin establishing a lunar outpost by 2020. The LRO also includes seven instruments that will help NASA characterize the moon's surface: DIVINER, LAMP, LEND, LOLA , CRATER, Mini-RF and LROC. Launch was on-time at 5:32 p.m. EDT June 18. Photo credit: NASA/Tony Gray

CONSTRUCTION OF A SMALL AUTOMATED CORONAGRAPH FOR OBSERVATIONS OF THE LUNAR Na EXOSPHERE

NASA Astrophysics Data System (ADS)

Tucker, Roy; Morgan, T. H.; Killen, R. M.

2013-10-01

We report on the final optical and mechanical design and the construction and initial testing of a small coronagraph at the Winer Observatory, near Sonoita, Arizona. The coronagraph includes a narrow band filter and low-light level camera to observe lunar exospheric sodium in the resonance lines of that element near 590 nm. Without the use of a coronagraph, the signal from sodium would be lost against light scattered by the Earth’s atmosphere and scattered light in the telescope. The design uses Commercial Off the Shelf Technology (COTS), and our goal is to obtain observations while the Lunar Atmosphere and Dust Environment Explorer (LADEE) mission is still in orbit.

Analysis of single quantum-dot mobility inside 1D nanochannel devices

NASA Astrophysics Data System (ADS)

Hoang, H. T.; Segers-Nolten, I. M.; Tas, N. R.; van Honschoten, J. W.; Subramaniam, V.; Elwenspoek, M. C.

2011-07-01

We visualized individual quantum dots using a combination of a confining nanochannel and an ultra-sensitive microscope system, equipped with a high numerical aperture lens and a highly sensitive camera. The diffusion coefficients of the confined quantum dots were determined from the experimentally recorded trajectories according to the classical diffusion theory for Brownian motion in two dimensions. The calculated diffusion coefficients were three times smaller than those in bulk solution. These observations confirm and extend the results of Eichmann et al (2008 Langmuir 24 714-21) to smaller particle diameters and more narrow confinement. A detailed analysis shows that the observed reduction in mobility cannot be explained by conventional hydrodynamic theory.

Dramatic Dione

NASA Image and Video Library

2018-03-12

Cassini captured this striking view of Saturn's moon Dione on July 23, 2012. Dione is about 698 miles (1,123 kilometers) across. Its density suggests that about a third of the moon is made up of a dense core (probably silicate rock) with the remainder of its material being water ice. At Dione's average temperature of -304 degrees Fahrenheit (-186 degrees Celsius), ice is so hard it behaves like rock. The image was taken with Cassini's narrow-angle camera at a distance of approximately 260,000 miles (418,000 kilometers) from Dione, through a polarized filter and a spectral filter sensitive to green light. The Cassini spacecraft ended its mission on Sept. 15, 2017. https://photojournal.jpl.nasa.gov/catalog/PIA17197

Near-surface Thermal Infrared Imaging of a Mixed Forest

NASA Astrophysics Data System (ADS)

Aubrecht, D. M.; Helliker, B. R.; Richardson, A. D.

2014-12-01

Measurement of an organism's temperature is of basic physiological importance and therefore necessary for ecosystem modeling, yet most models derive leaf temperature from energy balance arguments or assume it is equal to air temperature. This is because continuous, direct measurement of leaf temperature outside of a controlled environment is difficult and rarely done. Of even greater challenge is measuring leaf temperature with the resolution required to understand the underlying energy balance and regulation of plant processes. To measure leaf temperature through the year, we have mounted a high-resolution, thermal infrared camera overlooking the canopy of a temperate deciduous forest. The camera is co-located with an eddy covariance system and a suite of radiometric sensors. Our camera measures longwave thermal infrared (λ = 7.5-14 microns) using a microbolometer array. Suspended in the canopy within the camera FOV is a matte black copper plate instrumented with fine wire thermocouples that acts as a thermal reference for each image. In this presentation, I will discuss the challenges of continuous, long-term field operation of the camera, as well as measurement sensitivity to physical and environmental parameters. Based on this analysis, I will show that the uncertainties in converting radiometric signal to leaf temperature are well constrained. The key parameter for minimizing uncertainty is the emissivity of the objects being imaged: measuring the emissivity to within 0.01 enables leaf temperature to be calculated to within 0.5°C. Finally, I will present differences in leaf temperature observed amongst species. From our two-year record, we characterize high frequency, daily, and seasonal thermal signatures of leaves and crowns, in relation to environmental conditions. Our images are taken with sufficient spatial and temporal resolution to quantify the preferential heating of sunlit portions of the canopy and the cooling effect of wind gusts. Future work will be focused on correlations between hyperspectral vegetation indices, fluxes, and thermal signatures to characterize vegetation stress. As water stress increases, causing photosynthesis and transpiration to shutdown, heat fluxes, leaf temperature, and narrow band vegetation indices should report signatures of the affected processes.

Implementation of a Real-Time Stacking Algorithm in a Photogrammetric Digital Camera for Uavs

NASA Astrophysics Data System (ADS)

Audi, A.; Pierrot-Deseilligny, M.; Meynard, C.; Thom, C.

2017-08-01

In the recent years, unmanned aerial vehicles (UAVs) have become an interesting tool in aerial photography and photogrammetry activities. In this context, some applications (like cloudy sky surveys, narrow-spectral imagery and night-vision imagery) need a longexposure time where one of the main problems is the motion blur caused by the erratic camera movements during image acquisition. This paper describes an automatic real-time stacking algorithm which produces a high photogrammetric quality final composite image with an equivalent long-exposure time using several images acquired with short-exposure times. Our method is inspired by feature-based image registration technique. The algorithm is implemented on the light-weight IGN camera, which has an IMU sensor and a SoC/FPGA. To obtain the correct parameters for the resampling of images, the presented method accurately estimates the geometrical relation between the first and the Nth image, taking into account the internal parameters and the distortion of the camera. Features are detected in the first image by the FAST detector, than homologous points on other images are obtained by template matching aided by the IMU sensors. The SoC/FPGA in the camera is used to speed up time-consuming parts of the algorithm such as features detection and images resampling in order to achieve a real-time performance as we want to write only the resulting final image to save bandwidth on the storage device. The paper includes a detailed description of the implemented algorithm, resource usage summary, resulting processing time, resulting images, as well as block diagrams of the described architecture. The resulting stacked image obtained on real surveys doesn't seem visually impaired. Timing results demonstrate that our algorithm can be used in real-time since its processing time is less than the writing time of an image in the storage device. An interesting by-product of this algorithm is the 3D rotation estimated by a photogrammetric method between poses, which can be used to recalibrate in real-time the gyrometers of the IMU.

Tectonics of short-offset, slow-slipping transform zones in the FAMOUS area, Mid-Atlantic Ridge

NASA Astrophysics Data System (ADS)

Goud, Margaret R.; Karson, Jeffrey A.

1985-12-01

ANGUS photographs and ALVIN observational data from Fracture Zones A and B on the Mid-Atlantic Ridge near 37°N were examined for structural and sedimentological indications of the area's tectonics. Both transform fault zones are characterized by volcanic rubble, breccias, chalks, and undisturbed sediments typical of slow-slipping transforms. The photographic data consist of 16 camera-sled traverses from the FAMOUS Expedition using the ANGUS deep-towed camera system. These data cover several different morphotectonic provinces along the strike of both slow-slipping (2 cm yr-1) fracture zones. ALVIN data come from two dives in the central part of Fracture Zone B. The two fracture zones differ in their distribution of fractured and sheared chalks which indicate regions of strike-slip deformation along the transform. Evidence of shearing is confined to a very narrow region in the center of FZ A, whereas the zone of shear deformation is as much as 6 km wide across FZ B. Other differences include the morphology and depth of the transform valleys and their contiguous nodal basins and the extent of exposures of fresh-looking volcanic ridges in the nodal basin.

Visual cueing considerations in Nap-of-the-Earth helicopter flight head-slaved helmet-mounted displays

NASA Technical Reports Server (NTRS)

Grunwald, Arthur J.; Kohn, Silvia

1993-01-01

The pilot's ability to derive Control-Oriented Visual Field Information from teleoperated Helmet-Mounted displays in Nap-of-the-Earth flight, is investigated. The visual field with these types of displays, commonly used in Apache and Cobra helicopter night operations, originates from a relatively narrow field-of-view Forward Looking Infrared Radiation Camera, gimbal-mounted at the nose of the aircraft and slaved to the pilot's line-of-sight, in order to obtain a wide-angle field-of-regard. Pilots have encountered considerable difficulties in controlling the aircraft by these devices. Experimental simulator results presented here indicate that part of these difficulties can be attributed to head/camera slaving system phase lags and errors. In the presence of voluntary head rotation, these slaving system imperfections are shown to impair the Control-Oriented Visual Field Information vital in vehicular control, such as the perception of the anticipated flight path or the vehicle yaw rate. Since, in the presence of slaving system imperfections, the pilot will tend to minimize head rotation, the full wide-angle field-of-regard of the line-of-sight slaved Helmet-Mounted Display, is not always fully utilized.

VizieR Online Data Catalog: Multiwavelenght photometry of Sh 2-138 YSOs (Baug+, 2015)

NASA Astrophysics Data System (ADS)

Baug, T.; Ojha, D. K.; Dewangan, L. K.; Ninan, J. P.; Bhatt, B. C.; Ghosh, S. K.; Mallick, K. K.

2016-07-01

Optical BVRI imaging observations of the Sh2-138 region were carried out on 2005 September 8 using the Himalaya Faint Object Spectrograph and Camera (HFOSC) mounted on the 2 m Himalayan Chandra Telescope (HCT). In order to identify strong Hα emission sources in the Sh2-138 region, slitless Hα spectra were obtained using the HFOSC on 2007 November 16. Optical spectroscopic observations of the central brightest source were performed using the HFOSC on 2014 November 18. The newly installed TIFR Near Infrared Spectrometer and Imager Camera (TIRSPEC) on the HCT was used for NIR observations on 2014 November 18 under photometric conditions with an average seeing of 1.4 arcsec. We obtained NIR spectra of the central brightest source on 2014 May 29, using the TIRSPEC, in NIR Y (1.02-1.20um), J (1.21-1.48um), H (1.49-1.78um), and K (2.04-2.35um) bands. We conducted optical narrow-band imaging observations of the region in Hα filter (λ~6563Å, Δλ~100Å) with exposure times of 600s, 250s, and 50s on 2005 September 8 using the HFOSC. (1 data file).

Imaging of four planetary nebulae in the Magellanic Clouds using the Hubble Space Telescope Faint Object Camera

NASA Technical Reports Server (NTRS)

Blades, J. C.; Barlow, M. J.; Albrecht, R.; Barbieri, C.; Boksenberg, A.; Crane, P.; Deharveng, J. M.; Disney, M. J.; Jakobsen, P.; Kamperman, T. M.

1992-01-01

Using the Faint Object Camera on-board the Hubble Space Telescope, we have obtained images of four planetary nebulae (PNe) in the Magellanic Clouds, namely N2 and N5 in the SMC and N66 and N201 in the LMC. Each nebula was imaged through two narrow-band filters isolating forbidden O III 5007 and H-beta, for a nominal exposure time of 1000 s in each filter. In forbidden O III, SMC N5 shows a circular ring structure, with a peak-to-peak diameter of 0.26 arcsec and a FWHM of 0.35 arcsec while SMC N2 shows an elliptical ring structure with a peak-to-peak diameter of 0.26 x 0.21. The expansion ages corresponding to the observed structures in SMC N2 and N5 are of the order of 3000 yr. LMC N201 is very compact, with a FWHM of 0.2 arcsec in H-beta. The Type I PN LMC N66 is a multipolar nebula, with the brightest part having an extent of about 2 arcsec and with fainter structures extending over 4 arcsec.

Imminent Approach to Dione

NASA Image and Video Library

2015-08-20

This view from NASA Cassini spacecraft looks toward Saturn icy moon Dione, with giant Saturn and its rings in the background, just prior to the mission final close approach to the moon on August 17, 2015. At lower right is the large, multi-ringed impact basin named Evander, which is about 220 miles (350 kilometers) wide. The canyons of Padua Chasma, features that form part of Dione's bright, wispy terrain, reach into the darkness at left. Imaging scientists combined nine visible light (clear spectral filter) images to create this mosaic view: eight from the narrow-angle camera and one from the wide-angle camera, which fills in an area at lower left. The scene is an orthographic projection centered on terrain at 0.2 degrees north latitude, 179 degrees west longitude on Dione. An orthographic view is most like the view seen by a distant observer looking through a telescope. North on Dione is up. The view was acquired at distances ranging from approximately 106,000 miles (170,000 kilometers) to 39,000 miles (63,000 kilometers) from Dione and at a sun-Dione-spacecraft, or phase, angle of 35 degrees. Image scale is about 1,500 feet (450 meters) per pixel. http://photojournal.jpl.nasa.gov/catalog/PIA19650

Interdisciplinary scientist participation in the Phobos mission

NASA Technical Reports Server (NTRS)

1992-01-01

Data was acquired from VSK (2 wide-angle visible-NIR TV cameras at 0.4 to 0.6 micrometers and 0.8 to 1.1 micrometers, and a narrow-angle TV camera), KRFM (10-band UV-visible spectrometer at 0.3 to 0.6 micrometers and a 6-band radiometer at 5-50 micrometers), and ISM (a 128-channel NIR imaging spectrometer at 0.8 to 3 micrometers). These data provided improved mapping coverage of Phobos; improved mass, shape, and volume determinations, with the density shown to be lower than that of all known meteorites, suggesting a porous interior; evidence for a physically, spectrally and possibly compositionally heterogeneous surface; and proof that the spectral properties do not closely resemble those of unaltered carbonaceous chondrites, but show more resemblance to the spectra of altered mafic material. For Mars, the data show that the underlying rock type can be distinguished through the global dust cover; that the spectral properties and possibly composition vary laterally between and within the geologic provinces; that the surface physical properties vary laterally, and in many cases, the boundaries coincide with those of the geologic units; and the acquired data also demonstrate the value of reflectance spectroscopy and radiometry to the study of Martian geology.

2MASS J00423991+3017515: An AGN On The Run?

NASA Astrophysics Data System (ADS)

Hogg, James

2016-10-01

We have discovered a peculiar AGN, 2MASS J00423991+3017515, in a local (z=0.14), disturbed galaxy whose optical spectrum has multiple broad lines that are consistently offset from the narrow line emission and host galaxy absorption by 1530 km/s. The morphology of the host galaxy and spectral properties thus suggest this AGN may be a recoiling supermassive black hole (SMBH). Gravitational-wave recoil kicks result from the coalescence of two SMBHs and have implications for the early growth of high-redshift quasars and SMBH-galaxy co-evolution. We propose high-resolution imaging in the NIR, optical, and UV with the WFC3 camera on Hubble and high-resolution X-ray imaging and spectral follow-ups with the ACIS camera on Chandra to determine if the source of the kinematically-offset broad line emission is also spatially offset from the nucleus of the host galaxy. We request 3 orbits with Hubble and 8 ksec with Chandra to conduct these follow-up observations. If a single, spatially offset AGN is detected, this source will be strongest candidate for a recoiling AGN candidate discovered to date, providing a new, indirect constraint on SMBH spin evolution and merger rates.

Estimating the coordinates of pillars and posts in the parking lots for intelligent parking assist system

NASA Astrophysics Data System (ADS)

Choi, Jae Hyung; Kuk, Jung Gap; Kim, Young Il; Cho, Nam Ik

2012-01-01

This paper proposes an algorithm for the detection of pillars or posts in the video captured by a single camera implemented on the fore side of a room mirror in a car. The main purpose of this algorithm is to complement the weakness of current ultrasonic parking assist system, which does not well find the exact position of pillars or does not recognize narrow posts. The proposed algorithm is consisted of three steps: straight line detection, line tracking, and the estimation of 3D position of pillars. In the first step, the strong lines are found by the Hough transform. Second step is the combination of detection and tracking, and the third is the calculation of 3D position of the line by the analysis of trajectory of relative positions and the parameters of camera. Experiments on synthetic and real images show that the proposed method successfully locates and tracks the position of pillars, which helps the ultrasonic system to correctly locate the edges of pillars. It is believed that the proposed algorithm can also be employed as a basic element for vision based autonomous driving system.

Recurring Lineae on Slopes at Hale Crater, Mars

NASA Image and Video Library

2015-09-28

Dark, narrow streaks on Martian slopes such as these at Hale Crater are inferred to be formed by seasonal flow of water on contemporary Mars. The streaks are roughly the length of a football field. The imaging and topographical information in this processed, false-color view come from the High Resolution Imaging Science Experiment (HiRISE) camera on NASA's Mars Reconnaissance Orbiter. These dark features on the slopes are called "recurring slope lineae" or RSL. Planetary scientists using observations with the Compact Reconnaissance Imaging Spectrometer on the same orbiter detected hydrated salts on these slopes at Hale Crater, corroborating the hypothesis that the streaks are formed by briny liquid water. The image was produced by first creating a 3-D computer model (a digital terrain map) of the area based on stereo information from two HiRISE observations, and then draping a false-color image over the land-shape model. The vertical dimension is exaggerated by a factor of 1.5 compared to horizontal dimensions. The camera records brightness in three wavelength bands: infrared, red and blue-green. The draped image is one product from HiRISE observation ESP_03070_1440. http://photojournal.jpl.nasa.gov/catalog/PIA19916

VCSELs in short-pulse operation for time-of-flight applications

NASA Astrophysics Data System (ADS)

Moench, Holger; Gronenborn, Stephan; Gu, Xi; Gudde, Ralph; Herper, Markus; Kolb, Johanna; Miller, Michael; Smeets, Michael; Weigl, Alexander

2018-02-01

VCSEL arrays are the ideal light source for 3D imaging applications. The narrow emission spectrum and the ability for short pulses make them superior to LEDs. Combined with fast photodiodes or special camera chips spatial information can be obtained which is needed in diverse applications like camera autofocus, indoor navigation, 3D-object recognition, augmented reality or autonomously driving vehicles. Pulse operation at the ns scale and at low duty cycle can work with significantly higher current than traditionally used for VCSELs in continuous wave operation. With reduced thermal limitations at low average heat dissipation very high currents become feasible and tens of Watts output power have been realized with small VCSEL chips. The optical emission pattern of VCSELs can be tailored to the desired field of view using beam shaping elements. Such optical elements also enable laser safe class 1 products. A detailed analysis of the complete system and the operation mode is required to calculate the maximum permitted power for a safe system. The good VCSEL properties like robustness, stability over temperature and the potential for integrated solutions open a huge potential for VCSELs in new mass applications in the consumer and automotive markets.

Imaging experiment: The Viking Mars orbiter

USGS Publications Warehouse

Carr, M.H.; Baum, W.A.; Briggs, G.A.; Masursky, H.; Wise, D.W.; Montgomery, D.R.

1972-01-01

The general objectives of the Imaging Experiment on the Viking Orbiter are to aid the selection of Viking Lander sites, to map and monitor the chosen sites during lander operations, to aid in the selection of future landing sites, and to extend our knowledge of the planet. The imaging system consists of two identical vidicon cameras each attached to a 1026 mm T/8 telescope giving approximately 1?? square field of view. From an altitude of 1500 km the picture elements will be approximately 24m apart. The vidicon is coupled with an image intensifier which provides increased sensitivity and permits electronic shuttering and image motion compensation. A vidicon readout time of 2.24 sec enables pictures to be taken in rapid sequence for contiguous coverage at high resolution. The camera differs from those previously flown to Mars by providing contiguous coverage at high resolution on a single orbital pass, by having sufficient sensitivity to use narrow band color filters at maximum resolution, and by having response in the ultraviolet. These capabilities will be utelized to supplement lander observations and to extend our knowledge particularly of volcanic, erosional, and atmospheric phenomena on Mars. ?? 1972.

Thin-Film Quantum Dot Photodiode for Monolithic Infrared Image Sensors.

PubMed

Malinowski, Pawel E; Georgitzikis, Epimitheas; Maes, Jorick; Vamvaka, Ioanna; Frazzica, Fortunato; Van Olmen, Jan; De Moor, Piet; Heremans, Paul; Hens, Zeger; Cheyns, David

2017-12-10

Imaging in the infrared wavelength range has been fundamental in scientific, military and surveillance applications. Currently, it is a crucial enabler of new industries such as autonomous mobility (for obstacle detection), augmented reality (for eye tracking) and biometrics. Ubiquitous deployment of infrared cameras (on a scale similar to visible cameras) is however prevented by high manufacturing cost and low resolution related to the need of using image sensors based on flip-chip hybridization. One way to enable monolithic integration is by replacing expensive, small-scale III-V-based detector chips with narrow bandgap thin-films compatible with 8- and 12-inch full-wafer processing. This work describes a CMOS-compatible pixel stack based on lead sulfide quantum dots (PbS QD) with tunable absorption peak. Photodiode with a 150-nm thick absorber in an inverted architecture shows dark current of 10 -6 A/cm² at -2 V reverse bias and EQE above 20% at 1440 nm wavelength. Optical modeling for top illumination architecture can improve the contact transparency to 70%. Additional cooling (193 K) can improve the sensitivity to 60 dB. This stack can be integrated on a CMOS ROIC, enabling order-of-magnitude cost reduction for infrared sensors.

Narrow band vacuum ultraviolet radiation, produced by fast conical discharge

NASA Astrophysics Data System (ADS)

Antsiferov, P. S.; Dorokhin, L. A.; Koshelev, K. N.

2018-04-01

The article presents the experimental study of discharges in a conical cavity, filled with Ar at pressure 80 Pa. The electrical current driver (inductive storage with plasma erosion opening switch) supplies to the load electrical current pulse with growth rate about 1012 A s‑1 and maximal value 30–40 kA. The convergent conical shock wave starts from the inner surface of the discharge cavity and collapses in ‘zippering’ mode. The pin hole camera imaging with MCP detector (time resolution 5 ns) have demonstrated the appearance of effectively fast moving compact plasma with visible velocity v  =  (1.5  ±  0.14)  ×  107 cm s‑1. Plasma emits narrow band radiation in the spectral range of Rydberg series transitions of Ar VII, Ar VIII with quantum number up to n  =  9 (wavelength about 11 nm). The intensity of radiation is comparable with the total plasma emission in the range 10–50 nm. Charge exchange between multiply charged Ar ions and cold Ar atoms of working gas is proposed as the possible mechanism of the origin of the radiation.

Effects of age, blood pressure and antihypertensive treatments on retinal arterioles remodeling assessed by adaptive optics.

PubMed

Rosenbaum, David; Mattina, Alessandro; Koch, Edouard; Rossant, Florence; Gallo, Antonio; Kachenoura, Nadjia; Paques, Michel; Redheuil, Alban; Girerd, Xavier

2016-06-01

In humans, adaptive optics camera enables precise large-scale noninvasive retinal microcirculation evaluation to assess ageing, blood pressure and antihypertensive treatments respective roles on retinal arterioles anatomy. We used adaptive optics camera rtx1 (Imagine-Eyes, Orsay, France) to measure wall thickness, internal diameter and to calculate wall-to-lumen ratio (WLR) and wall cross-sectional area of retinal arterioles. This assessment was repeated within a short period in two subgroups of hypertensive individuals without or with a drug-induced blood pressure drop. In 1000 individuals, mean wall thickness, lumen diameter and WLR were 23.2 ± 3.9, 78.0 ± 10.9 and 0.300 ± 0.054 μm, respectively. Blood pressure and age both independently increased WLR by thickening arterial wall. In opposite, hypertension narrowed lumen in younger as compared to older individuals (73.2 ± 9.0 vs. 81.7 ± 10.2 μm; P < 0.001), whereas age exerted no influence on lumen diameter. Short-term blood pressure drop (-29.3 ± 17.3/-14.4 ± 10.0 mmHg) induced a WLR decrease (-6.0 ± 8.0%) because of lumen dilatation (+4.4 ± 5.9%) without wall thickness changes. By contrast, no modifications were observed in individuals with stable blood pressure. In treated and controlled hypertensives under monotherapy WLR normalization was observed because of combined wall decrease and lumen dilatation independently of antihypertensive pharmacological classes. In multivariate analysis, hypertension drug regimen was not an independent predictor of any retinal anatomical indices. Retinal arteriolar remodeling comprised blood pressure and age-driven wall thickening as well as blood pressure-triggered lumen narrowing in younger individuals. Remodeling reversal observed in controlled hypertensives seems to include short-term functional and long-term structural changes.

Built-in hyperspectral camera for smartphone in visible, near-infrared and middle-infrared lights region (second report): sensitivity improvement of Fourier-spectroscopic imaging to detect diffuse reflection lights from internal human tissues for healthcare sensors

NASA Astrophysics Data System (ADS)

Kawashima, Natsumi; Hosono, Satsuki; Ishimaru, Ichiro

2016-05-01

We proposed the snapshot-type Fourier spectroscopic imaging for smartphone that was mentioned in 1st. report in this conference. For spectroscopic components analysis, such as non-invasive blood glucose sensors, the diffuse reflection lights from internal human skins are very weak for conventional hyperspectral cameras, such as AOTF (Acousto-Optic Tunable Filter) type. Furthermore, it is well known that the spectral absorption of mid-infrared lights or Raman spectroscopy especially in long wavelength region is effective to distinguish specific biomedical components quantitatively, such as glucose concentration. But the main issue was that photon energies of middle infrared lights and light intensities of Raman scattering are extremely weak. For improving sensitivity of our spectroscopic imager, the wide-field-stop & beam-expansion method was proposed. Our line spectroscopic imager introduced a single slit for field stop on the conjugate objective plane. Obviously to increase detected light intensities, the wider slit width of the field stop makes light intensities higher, regardless of deterioration of spatial resolutions. Because our method is based on wavefront-division interferometry, it becomes problems that the wider width of single slit makes the diffraction angle narrower. This means that the narrower diameter of collimated objective beams deteriorates visibilities of interferograms. By installing the relative inclined phaseshifter onto optical Fourier transform plane of infinity corrected optical systems, the collimated half flux of objective beams derived from single-bright points on objective surface penetrate through the wedge prism and the cuboid glass respectively. These two beams interfere each other and form the infererogram as spatial fringe patterns. Thus, we installed concave-cylindrical lens between the wider slit and objective lens as a beam expander. We successfully obtained the spectroscopic characters of hemoglobin from reflected lights from human fingers.

Predicting grain yield using canopy hyperspectral reflectance in wheat breeding data.

PubMed

Montesinos-López, Osval A; Montesinos-López, Abelardo; Crossa, José; de Los Campos, Gustavo; Alvarado, Gregorio; Suchismita, Mondal; Rutkoski, Jessica; González-Pérez, Lorena; Burgueño, Juan

2017-01-01

Modern agriculture uses hyperspectral cameras to obtain hundreds of reflectance data measured at discrete narrow bands to cover the whole visible light spectrum and part of the infrared and ultraviolet light spectra, depending on the camera. This information is used to construct vegetation indices (VI) (e.g., green normalized difference vegetation index or GNDVI, simple ratio or SRa, etc.) which are used for the prediction of primary traits (e.g., biomass). However, these indices only use some bands and are cultivar-specific; therefore they lose considerable information and are not robust for all cultivars. This study proposes models that use all available bands as predictors to increase prediction accuracy; we compared these approaches with eight conventional vegetation indexes (VIs) constructed using only some bands. The data set we used comes from CIMMYT's global wheat program and comprises 1170 genotypes evaluated for grain yield (ton/ha) in five environments (Drought, Irrigated, EarlyHeat, Melgas and Reduced Irrigated); the reflectance data were measured in 250 discrete narrow bands ranging between 392 and 851 nm. The proposed models for the simultaneous analysis of all the bands were ordinal least square (OLS), Bayes B, principal components with Bayes B, functional B-spline, functional Fourier and functional partial least square. The results of these models were compared with the OLS performed using as predictors each of the eight VIs individually and combined. We found that using all bands simultaneously increased prediction accuracy more than using VI alone. The Splines and Fourier models had the best prediction accuracy for each of the nine time-points under study. Combining image data collected at different time-points led to a small increase in prediction accuracy relative to models that use data from a single time-point. Also, using bands with heritabilities larger than 0.5 only in Drought as predictor variables showed improvements in prediction accuracy.

Public-Requested Mars Image: Crater on Pavonis Mons

NASA Technical Reports Server (NTRS)

2003-01-01

MGS MOC Release No. MOC2-481, 12 September 2003

This image is in the first pair obtained in the Public Target Request program, which accepts suggestions for sites to photograph with the Mars Orbiter Camera on NASA's Mars Global Surveyor spacecraft.

It is a narrow-angle (high-resolution) view of a portion of the lower wall and floor of the caldera at the top of a martian volcano named Pavonis Mons. A companion picture is a wide-angle context image, taken at the same time as the high-resolution view. The white box in the context frame shows the location of the high-resolution picture.

[figure removed for brevity, see original site]

Pavonis Mons is a broad shield volcano. Its summit region is about 14 kilometers (8.7 miles) above the martian datum (zero-elevation reference level). The caldera is about 4.6 kilometers (2.8 miles) deep. The caldera formed by collapse--long ago--as molten rock withdrew to greater depths within the volcano. The high-resolution picture shows that today the floor and walls of this caldera are covered by a thick, textured mantle of dust, perhaps more than 1 meter (1 yard) deep. Larger boulders and rock outcroppings poke out from within this dust mantle. They are seen as small, dark dots and mounds on the lower slopes of the wall in the high-resolution image.

The narrow-angle Mars Orbiter Camera image has a resolution of 1.5 meters (about 5 feet) per pixel and covers an area 1.5 kilometers (0.9 mile) wide by 9 kilometers (5.6 miles) long. The context image, covering much of the summit region of Pavonis Mons, is about 115 kilometers (72 miles) wide. Sunlight illuminates both images from the lower left; north is toward the upper right; east to the right. The high-resolution view is located near 0.4 degrees north latitude, 112.8 degrees west longitude.

KSC-2009-3776

NASA Image and Video Library

2009-06-18

CAPE CANAVERAL, Fla. – Fire and smoke signal the liftoff of the Atlas V/Centaur carrying NASA's Lunar Reconnaissance Orbiter, or LRO, and NASA's Lunar Crater Observation and Sensing Satellite, known as LCROSS, toward orbit around the moon. Launch from Launch Complex 41 at Cape Canaveral Air Force Station in Florida was on-time at 5:32 p.m. EDT. The towers around the pad are part of the lightning protection system. LRO and LCROSS are the first missions in NASA's plan to return humans to the moon and begin establishing a lunar outpost by 2020. The LRO also includes seven instruments that will help NASA characterize the moon's surface: DIVINER, LAMP, LEND, LOLA , CRATER, Mini-RF and LROC. Photo credit: NASA/Tom Farrar, Kevin O'Connell

KSC-2009-3777

NASA Image and Video Library

2009-06-18

CAPE CANAVERAL, Fla. – Fire and smoke signal the liftoff of the Atlas V/Centaur carrying NASA's Lunar Reconnaissance Orbiter, or LRO, and NASA's Lunar Crater Observation and Sensing Satellite, known as LCROSS, toward orbit around the moon. Launch from Launch Complex 41 at Cape Canaveral Air Force Station in Florida was on-time at 5:32 p.m. EDT. The towers around the pad are part of the lightning protection system. LRO and LCROSS are the first missions in NASA's plan to return humans to the moon and begin establishing a lunar outpost by 2020. The LRO also includes seven instruments that will help NASA characterize the moon's surface: DIVINER, LAMP, LEND, LOLA , CRATER, Mini-RF and LROC. Photo credit: NASA/Tom Farrar, Kevin O'Connell

KSC-2009-3181

NASA Image and Video Library

2009-05-15

CAPE CANAVERAL, Fla. – At Astrotech Space Operations Facility in Titusville, Fla., NASA's Lunar Reconnaissance Orbiter, or LRO, and NASA's Lunar Crater Observation and Sensing Satellite, known as LCROSS, are being prepared for fairing installation. On either side are the two fairing sections that will be installed around the spacecraft for launch. The fairing is a molded structure that fits flush with the outside surface of the rocket and forms an aerodynamically smooth nose cone, protecting the spacecraft during launch and ascent. The LRO includes five instruments: DIVINER, LAMP, LEND, LOLA and LROC. They will be launched aboard an Atlas V/Centaur rocket no earlier than June 17 from Launch Complex-41 on Cape Canaveral Air Force Station in Florida. Photo credit: NASA/Jack Pfaller

KSC-2009-3186

NASA Image and Video Library

2009-05-15

CAPE CANAVERAL, Fla. – At Astrotech Space Operations Facility in Titusville, Fla., technicians closely watch as the first half of the fairing is moved into place for installation around NASA's Lunar Reconnaissance Orbiter, or LRO, and and NASA's Lunar Crater Observation and Sensing Satellite, known as LCROSS. At right is the second half. The fairing is a molded structure that fits flush with the outside surface of the rocket and forms an aerodynamically smooth nose cone, protecting the spacecraft during launch and ascent. The LRO includes five instruments: DIVINER, LAMP, LEND, LOLA and LROC. They will be launched aboard an Atlas V/Centaur rocket no earlier than June 17 from Launch Complex-41 on Cape Canaveral Air Force Station in Florida. Photo credit: NASA/Jack Pfaller

KSC-2009-3772

NASA Image and Video Library

2009-06-18

CAPE CANAVERAL, Fla. – Viewed across the Indian River Lagoon, the Atlas V/Centaur rocket carrying NASA's Lunar Reconnaissance Orbiter, or LRO, and NASA's Lunar Crater Observation and Sensing Satellite, known as LCROSS, trails a tail of smoke as it roars into the sky after launch from Launch Complex 41 at Cape Canaveral Air Force Station in Florida. Surrounding the pad are lightning towers. LRO and LCROSS are the first missions in NASA's plan to return humans to the moon and begin establishing a lunar outpost by 2020. The LRO also includes seven instruments that will help NASA characterize the moon's surface: DIVINER, LAMP, LEND, LOLA , CRATER, Mini-RF and LROC. Launch was on-time at 5:32 p.m. EDT June 18. Photo credit: NASA/Tony Gray

Lava Tubes as Martian Analog sites on Hawaii Island

NASA Astrophysics Data System (ADS)

Andersen, Christian; Hamilton, J. C.; Adams, M.

2013-10-01

The existence of geologic features similar to skylights seen in Mars Reconnaissance Orbiter HIRISE imagery suggest Martian lava tube networks. Along with pit craters, these features are evidence of a past era of vulcanism. If these were contemporary with the wet Mars eras, then it is suggestive that any Martian life may have retreated into these subsurface oases. Hawaii island has numerous lava tubes of differing ages, humidity, lengths and sizes that make ideal analog test environments for future Mars exploration. PISCES has surveyed multiple candidate sites during the past summer with a team of University of Hawaii at Hilo student interns. It should be noted that Lunar features have also been similarly discovered via Lunar Reconnaissance Orbiter LROC imagery.

Retinal arteriolar remodeling evaluated with adaptive optics camera: Relationship with blood pressure levels.

PubMed

Gallo, A; Mattina, A; Rosenbaum, D; Koch, E; Paques, M; Girerd, X

2016-06-01

To research a retinal arterioles wall-to-lumen ratio or lumen diameter cut-off that would discriminate hypertensive from normal subjects using adaptive optics camera. One thousand and five hundred subjects were consecutively recruited and Adaptive Optics Camera rtx1™ (Imagine-Eyes, Orsay, France) was used to measure wall thickness, internal diameter, to calculate wall-to-lumen ratio (WLR) and wall cross-sectional area of retinal arterioles. Sitting office blood pressure was measured once, just before retinal measurements and office blood pressure was defined as systolic blood pressure>=140mmHg and diastolic blood pressure>=90mmHg. ROC curves were constructed to determine cut-off values for retinal parameters to diagnose office hypertension. In another population of 276 subjects office BP, retinal arterioles evaluation and home blood pressure monitoring were obtained. The applicability of retinal WLR or diameter cut-off values were compared in patients with controlled, masked, white-coat and sustained hypertension. In 1500 patients, a WLR>0.31 discriminated office hypertensive subjects with a 0.57 sensitivity and 0.71 specificity. Lumen diameter<78.2μm discriminated office hypertension with a 0.73 sensitivity and a 0.52 specificity. In the other 276 patients, WLR was higher in sustained hypertension vs normotensive patients (0.330±0.06 vs 0.292±0.05; P<0.001) and diameter was narrower in masked hypertensive vs normotensive subjects (73.0±11.2 vs 78.5±11.6μm; P<0.005). A WLR higher than 0.31 is in favour of office arterial hypertension; a diameter under<78μm may indicate a masked hypertension. Retinal arterioles analysis through adaptive optics camera may help the diagnosis of arterial hypertension, in particular in case of masked hypertension. Copyright © 2016. Published by Elsevier SAS.

Design and implementation of a dual-wavelength intrinsic fluorescence camera system

NASA Astrophysics Data System (ADS)

Ortega-Martinez, Antonio; Musacchia, Joseph J.; Gutierrez-Herrera, Enoch; Wang, Ying; Franco, Walfre

2017-03-01

Intrinsic UV fluorescence imaging is a technique that permits the observation of spatial differences in emitted fluorescence. It relies on the fluorescence produced by the innate fluorophores in the sample, and thus can be used for marker-less in-vivo assessment of tissue. It has been studied as a tool for the study of the skin, specifically for the classification of lesions, the delimitation of lesion borders and the study of wound healing, among others. In its most basic setup, a sample is excited with a narrow-band UV light source and the resulting fluorescence is imaged with a UV sensitive camera filtered to the emission wavelength of interest. By carefully selecting the excitation/emission pair, we can observe changes in fluorescence associated with physiological processes. One of the main drawbacks of this simple setup is the inability to observe more than a single excitation/emission pair at the same time, as some phenomena are better studied when two or more different pairs are studied simultaneously. In this work, we describe the design and the hardware and software implementation of a dual wavelength portable UV fluorescence imaging system. Its main components are an UV camera, a dual wavelength UV LED illuminator (295 and 345 nm) and two different emission filters (345 and 390 nm) that can be swapped by a mechanical filter wheel. The system is operated using a laptop computer and custom software that performs basic pre-processing to improve the image. The system was designed to allow us to image fluorescent peaks of tryptophan and collagen cross links in order to study wound healing progression.

Section 1: Interfacial reactions and grain growth in ferroelectric SrBi{sub 2}Ta{sub 2}O (SBT) thin films on Si substrates

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dickerson, B.D.; Zhang, X.; Desu, S.B.

1997-04-01

Much of the cost of traditional infrared cameras based on narrow-bandgap photoelectric semiconductors comes from the cryogenic cooling systems required to achieve high detectivity. Detectivity is inversely proportional to noise. Generation-recombination noise in photoelectric detectors increases roughly exponentially with temperature, but thermal noise in photoelectric detectors increases only linearly with temperature. Therefore `thermal detectors perform far better at room temperature than 8-14 {mu}m photon detectors.` Although potentially more affordable, uncooled pyroelectric cameras are less sensitive than cryogenic photoelectric cameras. One way to improve the sensitivity to cost ratio is to deposit ferroelectric pixels with good electrical properties directly on mass-produced,more » image-processing chips. `Good` properties include a strong temperature dependence of the remanent polarization, P{sub r}, or the relative dielectric constant, {epsilon}{sub r}, for sensitive operation in pyroelectric or dielectric mode, respectively, below or above the Curie temperature, which is 320 C for SBT. When incident infrared radiation is chopped, small oscillations in pixel temperature produce pyroelectric or dielectric alternating currents. The sensitivity of ferroelectric thermal detectors depends strongly on pixel microstructure, since P{sub r} and {epsilon}{sub r} increase with grain size during annealing. To manufacture SBT pixels on Si chips, acceptable SBT grain growth must be achieved at the lowest possible oxygen annealing temperature, to avoid damaging the Si chip below. Therefore current technical progress describes how grain size, reaction layer thickness, and electrical properties develop during the annealing of SBT pixels deposited on Si.« less

II-VI Narrow-Bandgap Semiconductors for Optoelectronics

NASA Astrophysics Data System (ADS)

Baker, Ian

The field of narrow-gap II-VI materials is dominated by the compound semiconductor mercury cadmium telluride, (Hg1-x Cd x Te or MCT), which supports a large industry in infrared detectors, cameras and infrared systems. It is probably true to say that HgCdTe is the third most studied semiconductor after silicon and gallium arsenide. Hg1-x Cd x Te is the material most widely used in high-performance infrared detectors at present. By changing the composition x the spectral response of the detector can be made to cover the range from 1 μm to beyond 17 μm. The advantages of this system arise from a number of features, notably: close lattice matching, high optical absorption coefficient, low carrier generation rate, high electron mobility and readily available doping techniques. These advantages mean that very sensitive infrared detectors can be produced at relatively high operating temperatures. Hg1-x Cd x Te multilayers can be readily grown in vapor-phase epitaxial processes. This provides the device engineer with complex doping and composition profiles that can be used to further enhance the electro-optic performance, leading to low-cost, large-area detectors in the future. The main purpose of this chapter is to describe the applications, device physics and technology of II-VI narrow-bandgap devices, focusing on HgCdTe but also including Hg1-x Mn x Te and Hg1-x Zn x Te. It concludes with a review of the research and development programs into third-generation infrared detector technology (so-called GEN III detectors) being performed in centers around the world.

Narrow bandpass steep edge optical filter for the JAST/T80 telescope instrumentation

NASA Astrophysics Data System (ADS)

Reichel, S.; Brauneck, U.; Bourquin, S.; Marín-Franch, A.

2013-09-01

The Observatorio Astrofisico de Javalambre in Spain observes with its JAST/T80 telescope galaxies in the Local Universe in a systematic study. This is accomplished with a multi-band photometric all sky survey called Javalambre Photometric Local Universe Survey (J-PLUS). A wide field camera receives the signals from universe via optical filters. In this presentation the development and design of a narrow bandpass steep edge filter with wide suppression will be shown. The filter has a full width half maximum in the range of 13-15 nm (with <1 nm tolerance) with central wavelengths in the range 350-860nm and an average transmission larger than 90% in the passband. Signals beyond the passband (blocking range) have to be suppressed down to 250nm and up to 1050nm (spectral regime), where a blocking of OD 5 (transmission < 10-5) is required. The edges have to be steep for a small transition width from 5% to 80%. The spectral requirements result in a large number of layers which are deposited with magnetron sputtering. The transmitted wavefront error of the optical filter must be less than lambda/2 over the 100mm aperture and the central wavelength uniformity must be better than +/- 0.4% over the clear aperture. The filter consists of optical filter glass and a coated substrate in order to reach the spectral requirements. The substrate is coated with more than 120 layers. The total filter thickness was specified to be 8.0mm. Results of steep edge narrow bandpass filters will be demonstrated fulfilling all these demanding requirements.

Sex differences in knee joint loading: Cross-sectional study in geriatric population.

PubMed

Ro, Du Hyun; Lee, Dong Yeon; Moon, Giho; Lee, Sahnghoon; Seo, Sang Gyo; Kim, Seong Hwan; Park, In Woong; Lee, Myung Chul

2017-06-01

This study investigated sex differences in knee biomechanics and investigated determinants for difference in a geriatric population. Age-matched healthy volunteers (42 males and 42 females, average age 65 years) without knee OA were included in the study. Subjects underwent physical examination on their knee and standing full-limb radiography for anthropometric measurements. Linear, kinetic, and kinematic parameters were compared using a three-dimensional, 12-camera motion capture system. Gait parameters were evaluated and determinants for sex difference were evaluated with multiple regression analysis. Females had a higher peak knee adduction moment (KAM) during gait (p = 0.004). Females had relatively wider pelvis and narrower step width (both p < 0.001). However, coronal knee alignment was not significantly different between the sexes. Multiple regression analysis revealed that coronal alignment (b = 0.014, p < 0.001), step width (b = -0.010, p = 0.011), and pelvic width/height ratio (b = 1.703, p = 0.046) were significant determinants of peak KAM. Because coronal alignment was not different between the sexes, narrow step width and high pelvic width/height ratio of female were the main contributors to higher peak KAM in females. Sex differences in knee biomechanics were present in the geriatric population. Increased mechanical loading on the female knee, which was associated with narrow step width and wide pelvis, may play an important role in future development and progression of OA. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:1283-1289, 2017. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

The Magsat three axis arc second precision attitude transfer system

NASA Technical Reports Server (NTRS)

Schenkel, F. W.; Heins, R. J.

1981-01-01

The Magsat Attitude Transfer System (ATS), which provides attitude alteration in pitch, yaw, and roll is described. A remote vector magnetometer extends from Magsat on a 20 ft boom, requiring vector orientation by reference to coordinate axes determined by a set of star mapping cameras. The ATS was designed to perform in a solar illuminated environment by using an optically narrow bandwidth with synchronous demodulation at 9300 A. The pitch/yaw optical design, the electrooptics, and signal and switching diagrams are provided. Simple mirrors with no moving parts are placed on the magnetometer to reflect a collimated beam from the ATS for attitude indication, which is accurate to one part in 96. Alignment was completed within 24 hr after launch.

Moon Zoo: Making the public part of a crater survey algorithm

NASA Astrophysics Data System (ADS)

Gay, P. L.; Brown, S.; Huang, D.; Daus, C.; Lehan, C.; Robbins, S.

2011-10-01

The Moon Zoo citizen science website launched in May 2010 and invited the public to annotate images from the Lunar Reconnaissance Orbiter's Narrow Angle Camera (NAC). Tasks included marking the edges of craters with an ellipse tool, indicating where linear features (e.g. scarps) and special types of craters (e.g. dark haloed) are located with a box, and rating the number of boulders in an image. The goal of this project is to create crater and feature catalogues for large areas of the moon. In addition to doing science, Moon Zoo also seeks to educate its audience through educational content, to engage them through social media, and to understand them through research into their motivations and behaviors.

SOFIA/FORCAST Resolves 30 - 40 μm Extended Emission in Nearby AGN

NASA Astrophysics Data System (ADS)

Fuller, Lindsay; Lopez-Rodriguez, Enrique; Packham, Christopher C.; Ichikawa, Kohei; Togi, Aditya

2018-06-01

We present arcsecond-scale observations in the 30 - 40 μm range of seven nearby Seyfert galaxies observed from the Stratospheric Observatory For Infrared Astronomy (SOFIA) using the 31.5 and 37.1 μm filters of the Faint Object infraRed CAmera for the SOFIA Telescope (FORCAST). We find extended diffuse emission in the 37.1 μm images in our sample, and isolate this from unresolved torus emission. Using Spitzer/IRS spectra, we determine the dominant mid-infrared (MIR) emission source and attribute it to dust in the narrow line region (NLR) or star formation. We compare the optical NLR and radio jet axes to the extended 37.1 μm emission and find coincident axes for three sources.

Postcard from the Ring Plane

NASA Image and Video Library

2018-05-07

On March 13, 2006 Cassini's narrow-angle camera captured this look at Saturn and its rings, seen here nearly edge on. The frame also features Mimas and tiny Janus (above the rings), and Tethys (below the rings). "Above" and "below" the rings is mostly a matter of perspective here. All three moons and the rings orbit Saturn in roughly the same plane. The night side of Mimas is gently illuminated by "Saturnshine," sunlight reflected from the planet's cloud tops. Images taken using red, green and blue spectral filters were combined to create this natural color view, taken at a distance of approximately 1.7 million miles (2.7 million kilometers) from Saturn. The Cassini spacecraft ended its mission on Sept. 15, 2017. https://photojournal.jpl.nasa.gov/catalog/PIA18323

Faraday imaging at high temperatures

DOEpatents

Hackel, L.A.; Reichert, P.

1997-03-18

A Faraday filter rejects background light from self-luminous thermal objects, but transmits laser light at the passband wavelength, thus providing an ultra-narrow optical bandpass filter. The filter preserves images so a camera looking through a Faraday filter at a hot target illuminated by a laser will not see the thermal radiation but will see the laser radiation. Faraday filters are useful for monitoring or inspecting the uranium separator chamber in an atomic vapor laser isotope separation process. Other uses include viewing welds, furnaces, plasma jets, combustion chambers, and other high temperature objects. These filters are can be produced at many discrete wavelengths. A Faraday filter consists of a pair of crossed polarizers on either side of a heated vapor cell mounted inside a solenoid. 3 figs.

Regarding Rhea

NASA Image and Video Library

2016-08-01

Rhea, like many moons in the outer solar system, appears dazzlingly bright in full sunlight. This is the signature of the water ice that forms most of the moon's surface. Rhea (949 miles or 1,527 kilometers across) is Saturn's second largest moon after Titan. Its ancient surface is one of the most heavily cratered of all of Saturn's moons. Subtle albedo variations across the disk of Rhea hint at past geologic activity. This view looks toward the anti-Saturn hemisphere of Rhea. North on Rhea is up and rotated 36 degrees to the right. The image was taken with the Cassini spacecraft narrow-angle camera on June 3, 2016 using a spectral filter which preferentially admits wavelengths of ultraviolet light centered at 338 nanometers. http://photojournal.jpl.nasa.gov/catalog/PIA20495

Gravity's Rainbow

NASA Image and Video Library

2018-04-23

Saturn's rings display their subtle colors in this view captured on Aug. 22, 2009, by NASA's Cassini spacecraft. The particles that make up the rings range in size from smaller than a grain of sand to as large as mountains, and are mostly made of water ice. The exact nature of the material responsible for bestowing color on the rings remains a matter of intense debate among scientists. Images taken using red, green and blue spectral filters were combined to create this natural color view. Cassini's narrow-angle camera took the images at a distance of approximately 1.27 million miles (2.05 million kilometers) from the center of the rings. The Cassini spacecraft ended its mission on Sept. 15, 2017 https://photojournal.jpl.nasa.gov/catalog/PIA22418

Faraday imaging at high temperatures

DOEpatents

Hackel, Lloyd A.; Reichert, Patrick

1997-01-01

A Faraday filter rejects background light from self-luminous thermal objects, but transmits laser light at the passband wavelength, thus providing an ultra-narrow optical bandpass filter. The filter preserves images so a camera looking through a Faraday filter at a hot target illuminated by a laser will not see the thermal radiation but will see the laser radiation. Faraday filters are useful for monitoring or inspecting the uranium separator chamber in an atomic vapor laser isotope separation process. Other uses include viewing welds, furnaces, plasma jets, combustion chambers, and other high temperature objects. These filters are can be produced at many discrete wavelengths. A Faraday filter consists of a pair of crossed polarizers on either side of a heated vapor cell mounted inside a solenoid.

A unified planar measurement technique for compressible flows using laser-induced iodine fluorescence

NASA Technical Reports Server (NTRS)

Hartfield, Roy J., Jr.; Hollo, Steven D.; Mcdaniel, James C.

1992-01-01

A unified laser-induced fluorescence technique for conducting planar measurements of temperature, pressure and velocity in nonreacting, highly compressible flows has been developed, validated and demonstrated. Planar fluorescence from iodine, seeded into air, was induced by an argon-ion laser and collected using a liquid-nitrogen cooled CCD camera. In the measurement technique, temperature is determined from the fluorescence induced with the laser operated broad band. Pressure and velocity are determined from the shape and position of the fluorescence excitation spectrum which is measured with the laser operated narrow band. The measurement approach described herein provides a means of obtaining accurate, spatially-complete maps of the primary flow field parameters in a wide variety of cold supersonic and transonic flows.

Pair-Wise, Deformable Mirror, Image Plane-Based Diversity Electric Field Estimation for High Contrast Coronagraphy

NASA Technical Reports Server (NTRS)

Give'on, Amir; Kern, Brian D.; Shaklan, Stuart

2011-01-01

In this paper we describe the complex electric field reconstruction from image plane intensity measurements for high contrast coronagraphic imaging. A deformable mirror (DM) surface is modied with pairs of complementary shapes to create diversity in the image plane of the science camera where the intensity of the light is measured. Along with the Electric Field Conjugation correction algorithm, this estimation method has been used in various high contrast imaging testbeds to achieve the best contrasts to date both in narrow and in broad band light. We present the basic methodology of estimation in easy to follow list of steps, present results from HCIT and raise several open quations we are confronted with using this method.

Video Mosaicking for Inspection of Gas Pipelines

NASA Technical Reports Server (NTRS)

Magruder, Darby; Chien, Chiun-Hong

2005-01-01

A vision system that includes a specially designed video camera and an image-data-processing computer is under development as a prototype of robotic systems for visual inspection of the interior surfaces of pipes and especially of gas pipelines. The system is capable of providing both forward views and mosaicked radial views that can be displayed in real time or after inspection. To avoid the complexities associated with moving parts and to provide simultaneous forward and radial views, the video camera is equipped with a wide-angle (>165 ) fish-eye lens aimed along the axis of a pipe to be inspected. Nine white-light-emitting diodes (LEDs) placed just outside the field of view of the lens (see Figure 1) provide ample diffuse illumination for a high-contrast image of the interior pipe wall. The video camera contains a 2/3-in. (1.7-cm) charge-coupled-device (CCD) photodetector array and functions according to the National Television Standards Committee (NTSC) standard. The video output of the camera is sent to an off-the-shelf video capture board (frame grabber) by use of a peripheral component interconnect (PCI) interface in the computer, which is of the 400-MHz, Pentium II (or equivalent) class. Prior video-mosaicking techniques are applicable to narrow-field-of-view (low-distortion) images of evenly illuminated, relatively flat surfaces viewed along approximately perpendicular lines by cameras that do not rotate and that move approximately parallel to the viewed surfaces. One such technique for real-time creation of mosaic images of the ocean floor involves the use of visual correspondences based on area correlation, during both the acquisition of separate images of adjacent areas and the consolidation (equivalently, integration) of the separate images into a mosaic image, in order to insure that there are no gaps in the mosaic image. The data-processing technique used for mosaicking in the present system also involves area correlation, but with several notable differences: Because the wide-angle lens introduces considerable distortion, the image data must be processed to effectively unwarp the images (see Figure 2). The computer executes special software that includes an unwarping algorithm that takes explicit account of the cylindrical pipe geometry. To reduce the processing time needed for unwarping, parameters of the geometric mapping between the circular view of a fisheye lens and pipe wall are determined in advance from calibration images and compiled into an electronic lookup table. The software incorporates the assumption that the optical axis of the camera is parallel (rather than perpendicular) to the direction of motion of the camera. The software also compensates for the decrease in illumination with distance from the ring of LEDs.

Hubble Tarantula Treasury Project: Unraveling Tarantula's Web. I. Observational Overview and First Results

NASA Technical Reports Server (NTRS)

Sabbi, E.; Anderson, J.; Lennon, D. J.; van der Marel, R. P.; Aloisi, A.; Boyer, Martha L.; Cignoni, M.; De Marchi, G.; De Mink, S. E.; Evans, C. J.;

Dust Devil Tracks and Wind Streaks in the North Polar Region of Mars: A Study of the 2007 Phoenix Mars Lander Sites

NASA Technical Reports Server (NTRS)

Drake, Nathan B.; Tamppari, Leslie K.; Baker, R. David; Cantor, Bruce A.; Hale, Amy S.

2006-01-01

The 65-72 latitude band of the North Polar Region of Mars, where the 2007 Phoenix Mars Lander will land, was studied using satellite images from the Mars Global Surveyor (MGS) Mars Orbiter Camera Narrow-Angle (MOC-NA) camera. Dust devil tracks (DDT) and wind streaks (WS) were observed and recorded as surface evidence for winds. No active dust devils (DDs) were observed. 162 MOC-NA images, 10.3% of total images, contained DDT/WS. Phoenix landing Region C (295-315W) had the highest concentration of images containing DDT/WS per number of available images (20.9%); Region D (130-150W) had the lowest (3.5%). DDT and WS direction were recorded for Phoenix landing regions A (110-130W), B (240-260W), and C to infer local wind direction. Region A showed dominant northwest-southeast DDT/WS, Region B showed dominant north-south, east-west and northeast-southwest DDT/WS, and region C showed dominant west/northwest - east/southeast DDT/ WS. Results indicate the 2007 Phoenix Lander has the highest probability of landing near DDT/WS in landing Region C. Based on DDT/WS linearity, we infer Phoenix would likely encounter directionally consistent background wind in any of the three regions.

Visual field information in Nap-of-the-Earth flight by teleoperated Helmet-Mounted displays

NASA Technical Reports Server (NTRS)

Grunwald, Arthur J.; Kohn, S.; Merhav, S. J.

1991-01-01

The human ability to derive Control-Oriented Visual Field Information from teleoperated Helmet-Mounted displays in Nap-of-the-Earth flight, is investigated. The visual field with these types of displays originates from a Forward Looking Infrared Radiation Camera, gimbal-mounted at the front of the aircraft and slaved to the pilot's line-of-sight, to obtain wide-angle visual coverage. Although these displays are proved to be effective in Apache and Cobra helicopter night operations, they demand very high pilot proficiency and work load. Experimental work presented in the paper has shown that part of the difficulties encountered in vehicular control by means of these displays can be attributed to the narrow viewing aperture and head/camera slaving system phase lags. Both these shortcomings will impair visuo-vestibular coordination, when voluntary head rotation is present. This might result in errors in estimating the Control-Oriented Visual Field Information vital in vehicular control, such as the vehicle yaw rate or the anticipated flight path, or might even lead to visuo-vestibular conflicts (motion sickness). Since, under these conditions, the pilot will tend to minimize head rotation, the full wide-angle coverage of the Helmet-Mounted Display, provided by the line-of-sight slaving system, is not always fully utilized.

Visualization of Projectile Flying at High Speed in Dusty Atmosphere

NASA Astrophysics Data System (ADS)

Masaki, Chihiro; Watanabe, Yasumasa; Suzuki, Kojiro

2017-10-01

Considering a spacecraft that encounters particle-laden environment, such as dust particles flying up over the regolith by the jet of the landing thruster, high-speed flight of a projectile in such environment was experimentally simulated by using the ballistic range. At high-speed collision of particles on the projectile surface, they may be reflected with cracking into smaller pieces. On the other hand, the projectile surface will be damaged by the collision. To obtain the fundamental characteristics of such complicated phenomena, a projectile was launched at the velocity up to 400 m/s and the collective behaviour of particles around projectile was observed by the high-speed camera. To eliminate the effect of the gas-particle interaction and to focus on only the effect of the interaction between the particles and the projectile's surface, the test chamber pressure was evacuated down to 30 Pa. The particles about 400μm diameter were scattered and formed a sheet of particles in the test chamber by using two-dimensional funnel with a narrow slit. The projectile was launched into the particle sheet in the tangential direction, and the high-speed camera captured both projectile and particle motions. From the movie, the interaction between the projectile and particle sheet was clarified.

Implementation of remote monitoring and managing switches

NASA Astrophysics Data System (ADS)

Leng, Junmin; Fu, Guo

2010-12-01

In order to strengthen the safety performance of the network and provide the big convenience and efficiency for the operator and the manager, the system of remote monitoring and managing switches has been designed and achieved using the advanced network technology and present network resources. The fast speed Internet Protocol Cameras (FS IP Camera) is selected, which has 32-bit RSIC embedded processor and can support a number of protocols. An Optimal image compress algorithm Motion-JPEG is adopted so that high resolution images can be transmitted by narrow network bandwidth. The architecture of the whole monitoring and managing system is designed and implemented according to the current infrastructure of the network and switches. The control and administrative software is projected. The dynamical webpage Java Server Pages (JSP) development platform is utilized in the system. SQL (Structured Query Language) Server database is applied to save and access images information, network messages and users' data. The reliability and security of the system is further strengthened by the access control. The software in the system is made to be cross-platform so that multiple operating systems (UNIX, Linux and Windows operating systems) are supported. The application of the system can greatly reduce manpower cost, and can quickly find and solve problems.

Dunelands of Titan

NASA Image and Video Library

2015-11-02

Saturn's frigid moon Titan has some characteristics that are oddly similar to Earth, but still slightly alien. It has clouds, rain and lakes (made of methane and ethane), a solid surface (made of water ice), and vast dune fields (filled with hydrocarbon sands). The dark, H-shaped area seen here contains two of the dune-filled regions, Fensal (in the north) and Aztlan (to the south). Cassini's cameras have frequently monitored the surface of Titan (3200 miles or 5150 kilometers across) to look for changes in its features over the course of the mission. Any changes would help scientists better understand different phenomena like winds and dune formation on this strangely earth-like moon. For a closer view of Fensal-Aztlan, see PIA07732 . This view looks toward the leading side of Titan. North on Titan is up. The image was taken with the Cassini spacecraft narrow-angle camera on July 25, 2015 using a spectral filter sensitive to wavelengths of near-infrared light centered at 938 nanometers. The view was obtained at a distance of approximately 450,000 miles (730,000 kilometers) from Titan and at a Sun-Titan-spacecraft, or phase, angle of 32 degrees. Image scale is 3 miles (4 kilometers) per pixel. http://photojournal.jpl.nasa.gov/catalog/PIA18341

Effects of superhydrophobic surface on the propeller wake

NASA Astrophysics Data System (ADS)

Choi, Hongseok; Lee, Jungjin; Park, Hyungmin

2017-11-01

This study investigates the change in propeller wake when the superhydrophobic surface is applied on the propeller blade. The propeller rotates in a quiescent water tank, facing its bottom, with a rotational Reynolds number of 96000. To measure the three-dimensional flow fields, we use stereo PIV and a water prism is installed at the camera-side tank wall. Two cameras are tilted 30 degrees from the normal axis of the tank wall, satisfying schiempflug condition. Superhydrophobic surface is made by coating hydrophobic nanoparticles on the propeller blade. Measurements are done on two vertical planes (at the center of propeller hub and the blade tip), and are ensemble averaged being classified by blade phase of 0 and 90 degrees. Velocity fluctuation, turbulent kinetic energy, and vorticity are evaluated. With superhydrophobic surface, it is found that the turbulence level is significantly (20 - 30 %) reduced with a small penalty (less than 5%) in the streamwise momentum (i.e., thrust) generation. This is because the cone shaped propeller wake gets narrower and organized vortex structures are broken with the superhydrophobic surfaces. More detailed flow analysis will be given. Supported by NRF (NRF-2016R1C1B2012775, NRF-2016M2B2A9A02945068) programs of Korea government.

Hellas as a Possible Site of Ancient Ice-Covered Lakes on Mars

NASA Technical Reports Server (NTRS)

Moore, Jeffrey M.; Wilhelms, Don E.; DeVincenzi, Donald (Technical Monitor)

2002-01-01

Based on topographic, morphologic, and stratigraphic evidence, we propose that ancient water-laid sediment is the dominant component of deposits within Hellas Planitia, Mars. Multiply layered sediment is manifested by alternating benches and scarps visible in Mars Orbiting Camera narrow-angle (MOC NA) images. Viking Orbiter camera and MOC NA images were used to map contacts and stratigraphically order the different materials units within Hellas. Mar's Orbiting Laser Altimeter (MOLA) data reveal that the contacts of these sedimentary units, as well as a number of scarps or other abrupt changes in landscape texture, trace contours of constant elevation for thousands of km, and in one case all around the basin. Channels, consensually interpreted to be cut by water, lead into the basin. MOLA results indicate that the area encompassed by greater Hellas' highest closed contour is nearly one-fifth that of the entire northern plains, making the Hellas 'drainage' area much larger than previously reported. If lakes formed under climatic conditions similar to the modern Martian climate, they would develop thick ice carapaces, then the lakes would eventually sublimate away. Two units within Hellas exhibit a reticulate or honeycomb pattern we speculate are impressions made by lake-lowered ice blocks grounding into initially soft mud.

Spectrally resolved laser interference microscopy

NASA Astrophysics Data System (ADS)

Butola, Ankit; Ahmad, Azeem; Dubey, Vishesh; Senthilkumaran, P.; Singh Mehta, Dalip

2018-07-01

We developed a new quantitative phase microscopy technique, namely, spectrally resolved laser interference microscopy (SR-LIM), with which it is possible to quantify multi-spectral phase information related to biological specimens without color crosstalk using a color CCD camera. It is a single shot technique where sequential switched on/off of red, green, and blue (RGB) wavelength light sources are not required. The method is implemented using a three-wavelength interference microscope and a customized compact grating based imaging spectrometer fitted at the output port. The results of the USAF resolution chart while employing three different light sources, namely, a halogen lamp, light emitting diodes, and lasers, are discussed and compared. The broadband light sources like the halogen lamp and light emitting diodes lead to stretching in the spectrally decomposed images, whereas it is not observed in the case of narrow-band light sources, i.e. lasers. The proposed technique is further successfully employed for single-shot quantitative phase imaging of human red blood cells at three wavelengths simultaneously without color crosstalk. Using the present technique, one can also use a monochrome camera, even though the experiments are performed using multi-color light sources. Finally, SR-LIM is not only limited to RGB wavelengths, it can be further extended to red, near infra-red, and infra-red wavelengths, which are suitable for various biological applications.

Aspects of detection and tracking of ground targets from an airborne EO/IR sensor

NASA Astrophysics Data System (ADS)

Balaji, Bhashyam; Sithiravel, Rajiv; Daya, Zahir; Kirubarajan, Thiagalingam

2015-05-01

An airborne EO/IR (electro-optical/infrared) camera system comprises of a suite of sensors, such as a narrow and wide field of view (FOV) EO and mid-wave IR sensors. EO/IR camera systems are regularly employed on military and search and rescue aircrafts. The EO/IR system can be used to detect and identify objects rapidly in daylight and at night, often with superior performance in challenging conditions such as fog. There exist several algorithms for detecting potential targets in the bearing elevation grid. The nonlinear filtering problem is one of estimation of the kinematic parameters from bearing and elevation measurements from a moving platform. In this paper, we developed a complete model for the state of a target as detected by an airborne EO/IR system and simulated a typical scenario with single target with 1 or 2 airborne sensors. We have demonstrated the ability to track the target with `high precision' and noted the improvement from using two sensors on a single platform or on separate platforms. The performance of the Extended Kalman filter (EKF) is investigated on simulated data. Image/video data collected from an IR sensor on an airborne platform are processed using an image tracking by detection algorithm.

Hellas as a possible site of ancient ice-covered lakes on Mars

USGS Publications Warehouse

Moore, Johnnie N.; Wilhelms, D.E.

2001-01-01

Based on topographic, morphologic, and stratigraphic evidence, we propose that ancient water-laid sediment is the dominant component of deposits within Hellas Planitia, Mars. Multiple-layered sediment is manifested by alternating benches and scarps visible in Mars orbiting camera narrow-angle (MOC NA) images. Viking Orbiter camera and MOC NA images were used to map contacts and stratigraphically order the different materials units within Hellas. Mars orbiting laser altimeter (MOLA) data reveal that the contacts of these sedimentary units, as well as a number of scarps or other abrupt changes in landscape texture, trace contours of constant elevation for thousands of km, and in one case all around the basin. Channels, consensually interpreted to be cut by water, lead into the basin. MOLA results indicate that the area encompassed by greater Hellas' highest closed contour is nearly one-fifth that of the entire northern plains, making the Hellas "drainage" area much larger than previously reported. If lakes formed under climatic conditions similar to the modern Martian climate, they would develop thick ice carapaces, then the lakes would eventually sublimate away. Two units within Hellas exhibit a reticulate or honeycomb pattern, which we speculate are impressions made by lake-lowered ice blocks grounding into initially soft mud.

Novel instrumentation of multispectral imaging technology for detecting tissue abnormity

NASA Astrophysics Data System (ADS)

Yi, Dingrong; Kong, Linghua

2012-10-01

Multispectral imaging is becoming a powerful tool in a wide range of biological and clinical studies by adding spectral, spatial and temporal dimensions to visualize tissue abnormity and the underlying biological processes. A conventional spectral imaging system includes two physically separated major components: a band-passing selection device (such as liquid crystal tunable filter and diffraction grating) and a scientific-grade monochromatic camera, and is expensive and bulky. Recently micro-arrayed narrow-band optical mosaic filter was invented and successfully fabricated to reduce the size and cost of multispectral imaging devices in order to meet the clinical requirement for medical diagnostic imaging applications. However the challenging issue of how to integrate and place the micro filter mosaic chip to the targeting focal plane, i.e., the imaging sensor, of an off-shelf CMOS/CCD camera is not reported anywhere. This paper presents the methods and results of integrating such a miniaturized filter with off-shelf CMOS imaging sensors to produce handheld real-time multispectral imaging devices for the application of early stage pressure ulcer (ESPU) detection. Unlike conventional multispectral imaging devices which are bulky and expensive, the resulting handheld real-time multispectral ESPU detector can produce multiple images at different center wavelengths with a single shot, therefore eliminates the image registration procedure required by traditional multispectral imaging technologies.

Spatial Variations of Spectral Properties of (21) Lutetia as Observed by OSIRIS/Rosetta

NASA Astrophysics Data System (ADS)

Leyrat, Cedric; Sierks, H.; Barbieri, C.; Barucci, A.; Da Deppo, V.; De Leon, J.; Fulchignoni, M.; Fornasier, S.; Groussin, O.; Hviid, S. F.; Jorda, L.; Keller, H. U.; La Forgia, F.; Lara, L.; Lazzarin, M.; Magrin, S.; Marchi, S.; Thomas, N.; Schroder, S. E.; OSIRIS Team

2010-10-01

On July 10, 2010, the Rosetta ESA/NASA spacecraft successfully flew by the asteroid (21) Lutetia, which becomes the largest asteroid observed by a space probe. The closest approach occurred at 15H45 UTC at a relative speed of 15km/s and a relative distance of 3160 km. The Narrow Angle Camera (NAC) and the Wide Angle Camera (WAC) of the OSIRIS instrument onboard Rosetta acquired images at different phase angles ranging from almost zero to more than 150 degrees. The best spatial resolution (60 m/pixel) allowed to reveal a very complex topography with several features and different crater's surface densities. Spectrophotometric analysis of the data could suggest spatial variations of the albedo and spectral properties at the surface of the asteroid, at least in the northern hemisphere. Numerous sets of data have been obtained at different wavelengths from 270nm to 980nm. We will first present a color-color analysis of data in order to locate landscapes where surface variegation is present. We will also present a more accurate study of spectral properties using the shape model and different statistical methods. Possible variations of the surface spectral properties with the slope of the ground and the gravity field orientation will be discussed as well.

Geomorphological Mapping on the Southern Hemisphere of Comet 67P/Churyumov-Gerasimenko

NASA Astrophysics Data System (ADS)

Lee, Jui-Chi; Massironi, Matteo; Giacomini, Lorenza; Ip, Wing-Huen; El-Maarry, Mohamed R.

2016-04-01

Since its rendezvous with comet 67P/Churyumov-Gerasimenko on the sixth of August, 2014, the Rosetta spacecraft has carried out close-up observations of the nucleus and coma of this Jupiter family comet. The OSIRIS, the Scientific Imaging Camera System onboard the Rosetta spacecraft, which consists of a narrow-angle and wide-angle camera (NAC and WAC), has made detailed investigations of the physical properties and surface morphology of the comet. From May 2015, the southern hemisphere of the comet became visible and the adaptical resolution was high enough for us to do a detailed analysis of the surface. Previous work shows that the fine particle deposits are the most extensive geomorphological unit in the northern hemisphere. On the contrary, southern hemisphere is dominated by rocky-like stratified terrain. The southern hemisphere of the nucleus surface reveals quite different morphologies from the northern hemisphere. This could be linked to the different insolation condition between northern and southern hemisphere. As a result, surface geological processes could operate with a diverse intensity on the different sides of the comet nucleus. In this work, we provide the geomorphological maps of the southern hemisphere with linear features and geological units identified. The geomorphological maps described in this study allow us to understand the processes and the origin of the comet.

Soft gamma-ray detector for the ASTRO-H Mission

NASA Astrophysics Data System (ADS)

Watanabe, Shin; Tajima, Hiroyasu; Fukazawa, Yasushi; Blandford, Roger; Enoto, Teruaki; Kataoka, Jun; Kawaharada, Madoka; Kokubun, Motohide; Laurent, Philippe; Lebrun, François; Limousin, Olivier; Madejski, Greg; Makishima, Kazuo; Mizuno, Tsunefumi; Nakamori, Takeshi; Nakazawa, Kazuhiro; Mori, Kunishiro; Odaka, Hirokazu; Ohno, Masanori; Ohta, Masayuki; Sato, Goro; Sato, Rie; Takeda, Shin'ichiro; Takahashi, Hiromitsu; Takahashi, Tadayuki; Tanaka, Takaaki; Tashiro, Makoto; Terada, Yukikatsu; Uchiyama, Hideki; Uchiyama, Yasunobu; Yamada, Shinya; Yatsu, Yoichi; Yonetoku, Daisuke; Yuasa, Takayuki

2012-09-01

ASTRO-H is the next generation JAXA X-ray satellite, intended to carry instruments with broad energy coverage and exquisite energy resolution. The Soft Gamma-ray Detector (SGD) is one of ASTRO-H instruments and will feature wide energy band (60-600 keV) at a background level 10 times better than the current instruments on orbit. The SGD is complimentary to ASTRO-H’s Hard X-ray Imager covering the energy range of 5-80 keV. The SGD achieves low background by combining a Compton camera scheme with a narrow field-of-view active shield where Compton kinematics is utilized to reject backgrounds. The Compton camera in the SGD is realized as a hybrid semiconductor detector system which consists of silicon and CdTe (cadmium telluride) sensors. Good energy resolution is afforded by semiconductor sensors, and it results in good background rejection capability due to better constraints on Compton kinematics. Utilization of Compton kinematics also makes the SGD sensitive to the gamma-ray polarization, opening up a new window to study properties of gamma-ray emission processes. In this paper, we will present the detailed design of the SGD and the results of the final prototype developments and evaluations. Moreover, we will also present expected performance based on the measurements with prototypes.

Thin-Film Quantum Dot Photodiode for Monolithic Infrared Image Sensors †

PubMed Central

Georgitzikis, Epimitheas; Vamvaka, Ioanna; Frazzica, Fortunato; Van Olmen, Jan; De Moor, Piet; Heremans, Paul; Hens, Zeger; Cheyns, David

2017-01-01

Imaging in the infrared wavelength range has been fundamental in scientific, military and surveillance applications. Currently, it is a crucial enabler of new industries such as autonomous mobility (for obstacle detection), augmented reality (for eye tracking) and biometrics. Ubiquitous deployment of infrared cameras (on a scale similar to visible cameras) is however prevented by high manufacturing cost and low resolution related to the need of using image sensors based on flip-chip hybridization. One way to enable monolithic integration is by replacing expensive, small-scale III–V-based detector chips with narrow bandgap thin-films compatible with 8- and 12-inch full-wafer processing. This work describes a CMOS-compatible pixel stack based on lead sulfide quantum dots (PbS QD) with tunable absorption peak. Photodiode with a 150-nm thick absorber in an inverted architecture shows dark current of 10−6 A/cm2 at −2 V reverse bias and EQE above 20% at 1440 nm wavelength. Optical modeling for top illumination architecture can improve the contact transparency to 70%. Additional cooling (193 K) can improve the sensitivity to 60 dB. This stack can be integrated on a CMOS ROIC, enabling order-of-magnitude cost reduction for infrared sensors. PMID:29232871

SPADAS: a high-speed 3D single-photon camera for advanced driver assistance systems

NASA Astrophysics Data System (ADS)

Bronzi, D.; Zou, Y.; Bellisai, S.; Villa, F.; Tisa, S.; Tosi, A.; Zappa, F.

2015-02-01

Advanced Driver Assistance Systems (ADAS) are the most advanced technologies to fight road accidents. Within ADAS, an important role is played by radar- and lidar-based sensors, which are mostly employed for collision avoidance and adaptive cruise control. Nonetheless, they have a narrow field-of-view and a limited ability to detect and differentiate objects. Standard camera-based technologies (e.g. stereovision) could balance these weaknesses, but they are currently not able to fulfill all automotive requirements (distance range, accuracy, acquisition speed, and frame-rate). To this purpose, we developed an automotive-oriented CMOS single-photon camera for optical 3D ranging based on indirect time-of-flight (iTOF) measurements. Imagers based on Single-photon avalanche diode (SPAD) arrays offer higher sensitivity with respect to CCD/CMOS rangefinders, have inherent better time resolution, higher accuracy and better linearity. Moreover, iTOF requires neither high bandwidth electronics nor short-pulsed lasers, hence allowing the development of cost-effective systems. The CMOS SPAD sensor is based on 64 × 32 pixels, each able to process both 2D intensity-data and 3D depth-ranging information, with background suppression. Pixel-level memories allow fully parallel imaging and prevents motion artefacts (skew, wobble, motion blur) and partial exposure effects, which otherwise would hinder the detection of fast moving objects. The camera is housed in an aluminum case supporting a 12 mm F/1.4 C-mount imaging lens, with a 40°×20° field-of-view. The whole system is very rugged and compact and a perfect solution for vehicle's cockpit, with dimensions of 80 mm × 45 mm × 70 mm, and less that 1 W consumption. To provide the required optical power (1.5 W, eye safe) and to allow fast (up to 25 MHz) modulation of the active illumination, we developed a modular laser source, based on five laser driver cards, with three 808 nm lasers each. We present the full characterization of the 3D automotive system, operated both at night and during daytime, in both indoor and outdoor, in real traffic, scenario. The achieved long-range (up to 45m), high dynamic-range (118 dB), highspeed (over 200 fps) 3D depth measurement, and high precision (better than 90 cm at 45 m), highlight the excellent performance of this CMOS SPAD camera for automotive applications.

Dark Spots on Titan

NASA Image and Video Library

2005-05-02

This recent image of Titan reveals more complex patterns of bright and dark regions on the surface, including a small, dark, circular feature, completely surrounded by brighter material. During the two most recent flybys of Titan, on March 31 and April 16, 2005, Cassini captured a number of images of the hemisphere of Titan that faces Saturn. The image at the left is taken from a mosaic of images obtained in March 2005 (see PIA06222) and shows the location of the more recently acquired image at the right. The new image shows intriguing details in the bright and dark patterns near an 80-kilometer-wide (50-mile) crater seen first by Cassini's synthetic aperture radar experiment during a Titan flyby in February 2005 (see PIA07368) and subsequently seen by the imaging science subsystem cameras as a dark spot (center of the image at the left). Interestingly, a smaller, roughly 20-kilometer-wide (12-mile), dark and circular feature can be seen within an irregularly-shaped, brighter ring, and is similar to the larger dark spot associated with the radar crater. However, the imaging cameras see only brightness variations, and without topographic information, the identity of this feature as an impact crater cannot be conclusively determined from this image. The visual infrared mapping spectrometer, which is sensitive to longer wavelengths where Titan's atmospheric haze is less obscuring -- observed this area simultaneously with the imaging cameras, so those data, and perhaps future observations by Cassini's radar, may help to answer the question of this feature's origin. The new image at the right consists of five images that have been added together and enhanced to bring out surface detail and to reduce noise, although some camera artifacts remain. These images were taken with the Cassini spacecraft narrow-angle camera using a filter sensitive to wavelengths of infrared light centered at 938 nanometers -- considered to be the imaging science subsystem's best spectral filter for observing the surface of Titan. This view was acquired from a distance of 33,000 kilometers (20,500 miles). The pixel scale of this image is 390 meters (0.2 miles) per pixel, although the actual resolution is likely to be several times larger. http://photojournal.jpl.nasa.gov/catalog/PIA06234

Hα imaging for BeXRBs in the Small Magellanic Cloud

NASA Astrophysics Data System (ADS)

Maravelias, G.; Zezas, A.; Antoniou, V.; Hatzidimitriou, D.; Haberl, F.

2017-11-01

The Small Magellanic Cloud (SMC) hosts a large number of high-mass X-ray binaries, and in particular of Be/X-ray Binaries (BeXRBs; neutron stars orbiting OBe-type stars), offering a unique laboratory to address the effect of metalicity. One key property of their optical companion is Hα in emission, which makes them bright sources when observed through a narrow-band Hα filter. We performed a survey of the SMC Bar and Wing regions using wide-field cameras (WFI@MPG/ESO and MOSAIC@CTIO/Blanco) in order to identify the counterparts of the sources detected in our XMM-Newton survey of the same area. We obtained broad-band R and narrow-band Hα photometry, and identified ~10000 Hα emission sources down to a sensitivity limit of 18.7 mag (equivalent to ~B8 type Main Sequence stars). We find the fraction of OBe/OB stars to be 13% down to this limit, and by investigating this fraction as a function of the brightness of the stars we deduce that Hα excess peaks at the O9-B2 spectral range. Using the most up-to-date numbers of SMC BeXRBs we find their fraction over their parent population to be ~0.002 - 0.025 BeXRBs/OBe, a direct measurement of their formation rate.

Research on Distribution Characteristics of Lunar Faults

NASA Astrophysics Data System (ADS)

Lu, T.; Chen, S.; Lu, P.

2017-12-01

Circular and linear tectonics are two major types of tectonics on lunar surface. Tectonic characteristics are of significance for researching about lunar geological evolution. Linear tectonics refers to those structures extending linearly on a lunar surface. Their distribution are closely related to the internal geological actions of the moon. Linear tectonics can integrally or locally express the structural feature and the stress status as well as showing the geological information of the interior of the moon. Faults are of the largest number and are of a certain distribution regularity among the linear tectonics, and are always the focus of domestic and overseas lunar tectonic research. Based on remote sensing geology and theory of traditional tectonic geology, We use a variety of remote sensing data processing to establish lunar linear tectonic interpretation keys with lunar spectral, terrain and gravity data. On this basis, interpretation of faults of the whole moon was primarily conducted from Chang'e-2 CCD image data and reference to wide-angle camera data of LROC, laser altimeter data of LOLA and gravity data of GRAIL. Statistical analysis of the number and distribution characteristics of whole lunar faults are counted from three latitude ranges of low, middle and high latitudes, then analyze the azimuth characteristics of the faults at different latitudes. We concluded that S-N direction is a relatively developed orientation at low latitudes. Middle latitudes reveal six preferred orientations of N-E, N-W, NN-E, NN-W, N-EE and N-WW directions. There are sparse faults of E-W direction distribution at low and middle latitudes. Meanwhile, the largest number of faults of E-W direction on lunar surface are mainly distributed along high latitudes with continuity and regularity. Analyzing faults of Mare Imbrium by the method of Euler deconvolution. The result show that there are two different properties of faults in Mare Imbrium. In conclusion, we suggest that the dynamics mechanism of the formation of the lunar faults is mainly affected by despinning, followed by tidal force and global contraction.

Orbit Determination of the Lunar Reconnaissance Orbiter: Status and Recent Development

NASA Astrophysics Data System (ADS)

Neumann, G. A.; Mazarico, E.; Goossens, S. J.; Nicholas, J. B.; Wagner, R.; Speyerer, E. J.; Smith, D. E.; Zuber, M. T.

2016-12-01

The LRO mission has been operated since June 2009, and the productivity of its seven instruments has led to a wealth of new data and scientific results. The high-resolution data acquired benefit from precise orbit determination (OD), alleviating human intervention in their geolocation and co-registration. The initial position knowledge requirement (50 meters) was met with radio tracking data from the primary NASA White Sands ground station supported by USN, after combination with LOLA altimetric crossovers. LRO-specific gravity field solutions were thus determined and allowed radio-only OD to perform adequately, although secular inclination changes required frequent updates. The high-accuracy gravity fields from GRAIL, with <10 km resolution, further improved the radio-only orbit reconstruction quality. However, it is in part limited by the 0.3-0.5 mm/s measurement noise level in the S-band. One-way tracking through Laser Ranging can supplement the tracking available for OD with 28 Hz ranges with 20 cm single-shot precision, but is available only on the nearside. The LOLA altimetric data afford accurate, independent information about LRO's orbit, with a very different geometry that includes coverage over the lunar farside. With LOLA's highest-quality topographic model of the Moon and the Kaguya Terrain Camera stereo-derived elevation model, and their combination named SLDEM2015, another altimetric measurement is now possible to use in OD. This `direct altimetry' tracking type was developed to calibrate the laser boresight pointing of the IceSAT/GLAS altimeter, as differences in geolocated height of profiles with respect to an ocean surface reference geoid were primarily attributed to pointing errors. We extended this technique to short-scale, high-resolution targets, and can now use the SLDEM2015 topographic model as a basemap to match individual LOLA tracks during OD, adjusting both spacecraft position and pointing to minimize the discrepancies. Comparisons with the radio-only orbits through the mission are used to evaluate the benefit of this new tracking data type, which might be used for the OD of future lunar orbiters carrying a laser altimeter. LROC NAC images provide independent accuracy estimation, through the repeated views taken of anthropogenic features for instance.

Birth of the International Lunar Impact Astronomical Detection (ILIAD) network : first detections in Morocco

NASA Astrophysics Data System (ADS)

Ait Moulay Larbi, E.; Bouley, S.; Dassou, A.; Benkhaldoun, Z.; Baratoux, D.; Lazrek, M.

2013-12-01

We present the research environment of our network. We highlight some results of the analysis of the first Lunar Meteorides impacts detected in Morocco. We present an exemple of ground-based instrumentation to carry out a successful search for lunar flashes phenomena. We also discuss the interest to monotoring these phenomena by focusing on the interest of determining the positions of the craters on the moon. The precise determination of impact flashes is very advantageous, especially in the near future there will be several new craters identified by LROC or other robotic spacecraft cameras. The two flashes reported in this study are optimally situated on central region of the lunar disk, which reduce the mismatch between the barycenter of radiation and the actual position of the impact. Smaller-scale lunar features are easily identified after superposition of a large number of images in order to increase the signal to noise ratio and produce an optimal image of the non-illuminated fraction of the moon. The sub-pixel shift of each image relative to the first frame (base frame) was determined by fitting the correlation peak obtained in the Fourier space to a 2- dimensional gaussian following Schaum and McHugh [1996]; Baratoux et al. [2001]. To increase further the positioning, the signal of the flash is is fitted to a 2-dimensional gaussian for each frame (previously shifted to the base image) where the flash is present. The barycenter of the flash is given as the rounded to the nearest integer of the average centers of the 2-dimensional gaussian functions. Two impact flashes are detected from AGM observatory in Marrakech, respectively on the February 6, 2013, at 06:29:56.7 UT and April 14, 2013, 20:00:45.4 UT. The characteristics of each flash are given in the table below. the diameter of the crater formed on the lunar surface can be estimated using Gault's formula for craters of less than 100 m in diameter, the results show that the meteoroids are likely producing craters of about 2.5 m and 4.4 m in diameter for Flash 1 and 2, respectively.Characteristics of lunar impact flashes

Agreement in Cone Density Derived from Gaze-Directed Single Images Versus Wide-Field Montage Using Adaptive Optics Flood Illumination Ophthalmoscopy

PubMed Central

Chew, Avenell L.; Sampson, Danuta M.; Kashani, Irwin; Chen, Fred K.

2017-01-01

Purpose We compared cone density measurements derived from the center of gaze-directed single images with reconstructed wide-field montages using the rtx1 adaptive optics (AO) retinal camera. Methods A total of 29 eyes from 29 healthy subjects were imaged with the rtx1 camera. Of 20 overlapping AO images acquired, 12 (at 3.2°, 5°, and 7°) were used for calculating gaze-directed cone densities. Wide-field AO montages were reconstructed and cone densities were measured at the corresponding 12 loci as determined by field projection relative to the foveal center aligned to the foveal dip on optical coherence tomography. Limits of agreement in cone density measurement between single AO images and wide-field AO montages were calculated. Results Cone density measurements failed in 1 or more gaze directions or retinal loci in up to 58% and 33% of the subjects using single AO images or wide-field AO montage, respectively. Although there were no significant overall differences between cone densities derived from single AO images and wide-field AO montages at any of the 12 gazes and locations (P = 0.01–0.65), the limits of agreement between the two methods ranged from as narrow as −2200 to +2600, to as wide as −4200 to +3800 cones/mm2. Conclusions Cone density measurement using the rtx1 AO camera is feasible using both methods. Local variation in image quality and altered visibility of cones after generating montages may contribute to the discrepancies. Translational Relevance Cone densities from single AO images are not interchangeable with wide-field montage derived–measurements. PMID:29285417

Snapshot hyperspectral fovea vision system (HyperVideo)

NASA Astrophysics Data System (ADS)

Kriesel, Jason; Scriven, Gordon; Gat, Nahum; Nagaraj, Sheela; Willson, Paul; Swaminathan, V.

2012-06-01

The development and demonstration of a new snapshot hyperspectral sensor is described. The system is a significant extension of the four dimensional imaging spectrometer (4DIS) concept, which resolves all four dimensions of hyperspectral imaging data (2D spatial, spectral, and temporal) in real-time. The new sensor, dubbed "4×4DIS" uses a single fiber optic reformatter that feeds into four separate, miniature visible to near-infrared (VNIR) imaging spectrometers, providing significantly better spatial resolution than previous systems. Full data cubes are captured in each frame period without scanning, i.e., "HyperVideo". The current system operates up to 30 Hz (i.e., 30 cubes/s), has 300 spectral bands from 400 to 1100 nm (~2.4 nm resolution), and a spatial resolution of 44×40 pixels. An additional 1.4 Megapixel video camera provides scene context and effectively sharpens the spatial resolution of the hyperspectral data. Essentially, the 4×4DIS provides a 2D spatially resolved grid of 44×40 = 1760 separate spectral measurements every 33 ms, which is overlaid on the detailed spatial information provided by the context camera. The system can use a wide range of off-the-shelf lenses and can either be operated so that the fields of view match, or in a "spectral fovea" mode, in which the 4×4DIS system uses narrow field of view optics, and is cued by a wider field of view context camera. Unlike other hyperspectral snapshot schemes, which require intensive computations to deconvolve the data (e.g., Computed Tomographic Imaging Spectrometer), the 4×4DIS requires only a linear remapping, enabling real-time display and analysis. The system concept has a range of applications including biomedical imaging, missile defense, infrared counter measure (IRCM) threat characterization, and ground based remote sensing.

A hybrid thermal video and FTIR spectrometer system for rapidly locating and characterizing gas leaks

NASA Astrophysics Data System (ADS)

Williams, David J.; Wadsworth, Winthrop; Salvaggio, Carl; Messinger, David W.

2006-08-01

Undiscovered gas leaks, known as fugitive emissions, in chemical plants and refinery operations can impact regional air quality and present a loss of product for industry. Surveying a facility for potential gas leaks can be a daunting task. Industrial leak detection and repair programs can be expensive to administer. An efficient, accurate and cost effective method for detecting and quantifying gas leaks would both save industries money by identifying production losses and improve regional air quality. Specialized thermal video systems have proven effective in rapidly locating gas leaks. These systems, however, do not have the spectral resolution for compound identification. Passive FTIR spectrometers can be used for gas compound identification, but using these systems for facility surveys is problematic due to their small field of view. A hybrid approach has been developed that utilizes the thermal video system to locate gas plumes using real time visualization of the leaks, coupled with the high spectral resolution FTIR spectrometer for compound identification and quantification. The prototype hybrid video/spectrometer system uses a sterling cooled thermal camera, operating in the MWIR (3-5 μm) with an additional notch filter set at around 3.4 μm, which allows for the visualization of gas compounds that absorb in this narrow spectral range, such as alkane hydrocarbons. This camera is positioned alongside of a portable, high speed passive FTIR spectrometer, which has a spectral range of 2 - 25 μm and operates at 4 cm -1 resolution. This system uses a 10 cm telescope foreoptic with an onboard blackbody for calibration. The two units are optically aligned using a turning mirror on the spectrometer's telescope with the video camera's output.

Co-registration of Laser Altimeter Tracks with Digital Terrain Models and Applications in Planetary Science

NASA Technical Reports Server (NTRS)

Glaeser, P.; Haase, I.; Oberst, J.; Neumann, G. A.

2013-01-01

We have derived algorithms and techniques to precisely co-register laser altimeter profiles with gridded Digital Terrain Models (DTMs), typically derived from stereo images. The algorithm consists of an initial grid search followed by a least-squares matching and yields the translation parameters at sub-pixel level needed to align the DTM and the laser profiles in 3D space. This software tool was primarily developed and tested for co-registration of laser profiles from the Lunar Orbiter Laser Altimeter (LOLA) with DTMs derived from the Lunar Reconnaissance Orbiter (LRO) Narrow Angle Camera (NAC) stereo images. Data sets can be co-registered with positional accuracy between 0.13 m and several meters depending on the pixel resolution and amount of laser shots, where rough surfaces typically result in more accurate co-registrations. Residual heights of the data sets are as small as 0.18 m. The software can be used to identify instrument misalignment, orbit errors, pointing jitter, or problems associated with reference frames being used. Also, assessments of DTM effective resolutions can be obtained. From the correct position between the two data sets, comparisons of surface morphology and roughness can be made at laser footprint- or DTM pixel-level. The precise co-registration allows us to carry out joint analysis of the data sets and ultimately to derive merged high-quality data products. Examples of matching other planetary data sets, like LOLA with LRO Wide Angle Camera (WAC) DTMs or Mars Orbiter Laser Altimeter (MOLA) with stereo models from the High Resolution Stereo Camera (HRSC) as well as Mercury Laser Altimeter (MLA) with Mercury Dual Imaging System (MDIS) are shown to demonstrate the broad science applications of the software tool.

ARC-1986-AC86-7009

NASA Image and Video Library

1986-01-17

Range : 9.1 million miles (5.7 million miles) P-29478C These two images pictures of Uranus, one in true color and the other in false color, were shot by Voyager 2's narrow angle camera. The picture at left has been processed to show Uranus as the human eye would see from the vantage point of the spacecraft. The image is a composite of shots taken through blue, green, and orange filters. The darker shadings on the upper right of the disk correspond to day-night boundaries on the planet. Beyond this boundary lies the hidden northern hemisphere of Uranus, which currently remains in total darkness as the planet rotates. The blue-green color results from the aborption of red light by methane gas in Uranus' deep, cold, and remarkably clear atmosphere. The picture at right uses false color and extreme contrast to bring out subtle details in the polar region of Uranus. Images obtained through ultraviolet, violet, and orange filters were respectively converted to the same blue, green, and red colors used to produce the picture at left. The very slight contrasts visible in true color are greatly exaggerated here. In this false colr picture, Uranus reveals a dark polar hood surrounded by aseries of progressively lighter concentric bands. One possible explanation is that a brownish haze or smog, concentrated around the pole, is arranged into bands of zonal motions of the upper atmosphere. Several artifacts of the optics and processing are visible. The occasional donut shapes are shadows cast by dust in the camera optics;the processing needed to bring ot faint features also bring out camera blemishes. in addition, the bright pink strip at the lower edge of the planets limb is an artifact of the image enhancement. In fact, the limb is dark and uniform in color around the planet.

Memoris, A Wide Angle Camera For Bepicolombo

NASA Astrophysics Data System (ADS)

Cremonese, G.; Memoris Team

In order to answer to the Announcement of Opportunity of ESA for the BepiColombo payload, we are working on a wide angle camera concept named MEMORIS (MEr- cury MOderate Resolution Imaging System). MEMORIS will performe stereoscopic images of the whole Mercury surface using two different channels at +/- 20 degrees from the nadir point. It will achieve a spatial resolution of 50m per pixel at 400 km from the surface (peri-Herm), corresponding to a vertical resolution of about 75m with the stereo performances. The scientific objectives will be addressed by MEMORIS may be identified as follows: Estimate of surface age based on crater counting Crater morphology and degrada- tion Stratigraphic sequence of geological units Identification of volcanic features and related deposits Origin of plain units from morphological observations Distribution and type of the tectonic structures Determination of relative age among the structures based on cross-cutting relationships 3D Tectonics Global mineralogical mapping of main geological units Identification of weathering products The last two items will come from the multispectral capabilities of the camera utilizing 8 to 12 (TBD) broad band filters. MEMORIS will be equipped by a further channel devoted to the observations of the tenuous exosphere. It will look at the limb on a given arc of the BepiColombo orbit, in so doing it will observe the exosphere above a surface latitude range of 25-75 degrees in the northern emisphere. The exosphere images will be obtained above the surface just observed by the other two channels, trying to find possible relantionship, as ground-based observations suggest. The exospheric channel will have four narrow-band filters centered on the sodium and potassium emissions and the adjacent continua.

Miranda - 'Chevron' Grooves

NASA Technical Reports Server (NTRS)

1986-01-01

This image of Miranda, obtained by Voyager 2 on approach, shows an unusual 'chevron' figure and regions of distinctly differing terrain on the Uranian moon. Voyager was 42,000 kilometers (26,000 miles) away when its narrow-angle camera acquired this clear-filter view. Grooved areas baring light and dark bands, distinct from other areas of mottled terrain, are visible at this resolution of about 600 meters (2,000 feet). The bright V-shaped feature in the grooved areas is the 'chevron' observed in earlier, lower-resolution images. Cutting across the bands are sinuous scarps, probably faults. Superimposed on both types of terrain are many bowl-shaped impact craters less than 5 km (3 mi) wide. The entire picture spans an area about 220 km (140 mi) across. The Voyager project is managed for NASA by the Jet Propulsion Laboratory.

Tethys the Spy

NASA Image and Video Library

2014-12-15

Tethys appears to be peeking out from behind Rhea, watching the watcher. Scientists believe that Tethys' surprisingly high albedo is due to the water ice jets emerging from its neighbor, Enceladus. The fresh water ice becomes the E ring and can eventually arrive at Tethys, giving it a fresh surface layer of clean ice. Lit terrain seen here is on the anti-Saturn side of Rhea. North on Rhea is up. The image was taken in red light with the Cassini spacecraft narrow-angle camera on April 20, 2012. The view was obtained at a distance of approximately 1.1 million miles (1.8 million kilometers) from Rhea and at a Sun-Rhea-spacecraft, or phase, angle of 59 degrees. Image scale is 7 miles (11 kilometers) per pixel. http://photojournal.jpl.nasa.gov/catalog/PIA18293

Path to the Dark Side

NASA Image and Video Library

2015-03-09

The moon Iapetus, like the "force" in Star Wars, has both a light side and a dark side. Scientists think that Iapetus' (914 miles or 1471 kilometers across) dark/light asymmetry was actually created by material migrating away from the dark side. For a simulation of how scientists think the asymmetry formed, see Thermal Runaway Model . Lit terrain seen here is on the Saturn-facing hemisphere of Iapetus. North on Iapetus is up and rotated 43 degrees to the right. The image was taken in green light with the Cassini spacecraft narrow-angle camera on Jan. 4, 2015. The view was acquired at a distance of approximately 2.5 million miles (4 million kilometers) from Iapetus. Image scale is 15 miles (24 kilometers) per pixel. http://photojournal.jpl.nasa.gov/catalog/pia18307

Dreamy Swirls on Saturn

NASA Image and Video Library

2017-09-12

NASA's Cassini spacecraft gazed toward the northern hemisphere of Saturn to spy subtle, multi-hued bands in the clouds there. This view looks toward the terminator -- the dividing line between night and day -- at lower left. The sun shines at low angles along this boundary, in places highlighting vertical structure in the clouds. Some vertical relief is apparent in this view, with higher clouds casting shadows over those at lower altitude. Images taken with the Cassini spacecraft narrow-angle camera using red, green and blue spectral filters were combined to create this natural-color view. The images were acquired on Aug. 31, 2017, at a distance of approximately 700,000 miles (1.1 million kilometers) from Saturn. Image scale is about 4 miles (6 kilometers) per pixel. https://photojournal.jpl.nasa.gov/catalog/PIA21888

Neptune's Southern Hemisphere

NASA Technical Reports Server (NTRS)

1989-01-01

This photograph of Neptune's southern hemisphere was taken by the narrow-angle camera on NASA's Voyager 2 when the spacecraft was 4.2 million km (2.6 million miles) from the planet. The smallest features that can be seen are 38 km (24 miles) across. The almond-shaped structure at the left is a large cloud system that has been seen for several weeks. Internal details in the feature have become increasingly apparent as Voyager 2 has approached. Systems with similar shapes in Jupiter's atmosphere rotate about their centers, rolling in the local winds that increase toward the south. However, the wispy nature of the white central clouds in this Neptunian feature make confirmation of the system's rotation difficult. The Voyager Mission is conducted by JPL for NASA's Office of Space Science and Applications.

Structure of the runaway electron loss during induced disruptions in TEXTOR

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wongrach, K.; Finken, K. H.; Willi, O.

2015-10-15

The loss of runaway electrons during an induced disruption is recorded by a synchrotron imaging technique using a fast infrared CCD camera. The loss is predominantly diffuse. During the “spiky-loss phase”, when the runaway beam moves close to the wall, a narrow channel between the runaway column and a scintillator probe is formed and lasts until the runaway beam is terminated. In some cases, the processed images show a stripe pattern at the plasma edge. A comparison between the MHD dominated disruptions and the MHD-free disruption is performed. A new mechanism of plasma disruptions with the runaway electron generation andmore » a novel model which reproduces many characteristic features of the plasma beam evolution during a disruption is briefly described.« less

2MASS J00423991+3017515: An AGN On The Run?

NASA Astrophysics Data System (ADS)

Hogg, James

2016-09-01

We have discovered a peculiar AGN, 2MASS J00423991+3017515, in a local (z=0.14), disturbed galaxy whose optical spectrum has multiple broad lines that are consistently offset from the narrow line emission and host galaxy absorption by 1530 km/s. The morphology of the host galaxy and spectral properties thus suggest this AGN may be a recoiling supermassive black hole (SMBH). We propose high-resolution X-ray imaging and spectral follow-ups with the ACIS camera on Chandra to determine if the source of the kinematically-offset broad line emission is also spatially offset from the nucleus of the host galaxy. If a single, spatially offset AGN is detected, this source will be strongest candidate for a recoiling AGN candidate discovered to date.

A Glimpse of Atlas

NASA Technical Reports Server (NTRS)

2005-01-01

Saturn's little moon Atlas orbits Saturn between the outer edge of the A ring and the fascinating, twisted F ring. This image just barely resolves the disk of Atlas, and also shows some of the knotted structure for which the F ring is known. Atlas is 32 kilometers (20 miles) across.

The bright outer edge of the A ring is overexposed here, but farther down the image several bright ring features can be seen.

The image was taken in visible light with the Cassini spacecraft narrow-angle camera on April 25, 2005, at a distance of approximately 2.4 million kilometers (1.5 million miles) from Atlas and at a Sun-Atlas-spacecraft, or phase, angle of 60 degrees. Resolution in the original image was 14 kilometers (9 miles) per pixel.

Neptune's small dark spot (D2)

NASA Technical Reports Server (NTRS)

1999-01-01

This bulls-eye view of Neptune's small dark spot (D2) was obtained by Voyager 2's narrow-angle camera. Banding surrounding the feature indicates unseen strong winds, while structures within the bright spot suggest both active upwelling of clouds and rotation about the center. A rotation rate has not yet been measured, but the V-shaped structure near the right edge of the bright area indicates that the spot rotates clockwise. Unlike the Great Red Spot on Jupiter, which rotates counterclockwise, if the D2 spot on Neptune rotates clockwise, the material will be descending in the dark oval region. The fact that infrared data will yield temperature information about the region above the clouds makes this observation especially valuable. The Voyager Mission is conducted by JPL for NASA's Office of Space Science and Applications.

Common Raven (Corvus corax) kleptoparasitism at a Golden Eagle (Aquila chyrsaetos) nest in southern Nevada

USGS Publications Warehouse

Simes, Matthew; Johnson, Diego R.; Streit, Justin; Longshore, Kathleen M.; Nussear, Kenneth E.; Esque, Todd C.

2017-01-01

The Common Raven (Corvus corax) is a ubiquitous species in the Mojave Desert of southern Nevada and California. From 5 to 24 May 2014, using remote trail cameras, we observed ravens repeatedly kleptoparasitizing food resources from the nest of a pair of Golden Eagles (Aquila chyrsaetos) in the Spring Mountains of southern Nevada. The ravens fed on nine (30%) of the 30 prey items delivered to the nest during the chick rearing period. Kleptoparasitic behavior by the ravens decreased as the eagle nestling matured to seven weeks of age, suggesting a narrow temporal window in which ravens can successfully engage in kleptoparasitic behavior at eagle nests. The observation of kleptoparasitism by Common Ravens at the nest suggests potential risks to young Golden Eagles from Common Ravens.

Technical Summary of the Half-Degree Imager (HDI)

NASA Astrophysics Data System (ADS)

Richmond, Michael W.

2017-01-01

The Half-Degree Imager (HDI) was first attached to the WIYN 0.9-m Telescope in October, 2013. In the three years since then, it has served a large community of astronomers throughout the WIYN 0.9-m consortium. The large field of view and relatively short readout time, combined with a large selection of broad-band and narrow-band filters, make HDI a powerful tool for large-area surveys. I will provide a summary of the technical features of this CCD camera and its operations, and present statistics on its use -- showing the fraction of time lost due to bad weather and technical problems. I will reserve time to answer questions from the audience, including those who may be interested in using HDI for their own projects.

Parental history of hypertension is associated with narrower retinal arteriolar caliber in young girls.

PubMed

Gopinath, Bamini; Baur, Louise A; Hardy, Louise L; Wang, Jie Jin; Teber, Erdahl; Wong, Tien Y; Mitchell, Paul

2011-09-01

We aimed to assess the associations between parental history of hypertension and indicators of cardiovascular risk (retinal vessel diameter, presence of obesity, and elevated blood pressure) in prepubertal children. There were 1739 (77.7% of those eligible) 6-year-old students (863 girls and 876 boys) who were examined from a random cluster sample of 34 Sydney schools. Parents completed questionnaires about their medical conditions, including whether they have/had hypertension. Retinal images were taken with a digital fundus camera, and retinal vessel caliber was quantified using computer software. Anthropometric (height, weight, percentage of body fat, and body mass index) and blood pressure measures were collected. There were 160 children (9.2%) with a positive parental history of hypertension (either biological mother and/or father). Children with a positive versus negative parental history of hypertension had significantly higher body mass index (16.8 versus 16.5 kg/m(2); P=0.04) and systolic blood pressure (101.3 versus 99.8 mm Hg; P=0.01). Girls with positive versus negative parental history of hypertension had significantly higher diastolic blood pressure (≈3.1 mm Hg; P=0.01) and narrower retinal arteriolar caliber (≈4.3 μm; P=0.0004). Positive parental history of hypertension was not associated with mean retinal vascular caliber among boys. We show that a positive parental history of hypertension in healthy prepubertal girls, but not boys, is associated with narrower retinal arteriolar vessels, likely conveying a predisposition to develop hypertension later in life. These findings may indicate the need for cardiovascular disease prevention measures starting early in life among offspring of hypertensive parents.

Moon Convention

NASA Image and Video Library

2015-03-23

People with similar jobs or interests hold conventions and meetings, so why shouldn't moons? Pandora, Prometheus, and Pan -- seen here, from right to left -- also appear to be holding some sort of convention in this image. Some moons control the structure of nearby rings via gravitational "tugs." The cumulative effect of the moon's tugs on the ring particles can keep the rings' edges from spreading out as they are naturally inclined to do, much like shepherds control their flock. Pan is a prototypical shepherding moon, shaping and controlling the locations of the inner and outer edges of the Encke gap through a mechanism suggested in 1978 to explain the narrow Uranian rings. However, though Prometheus and Pandora have historically been called "the F ring shepherd moons" due to their close proximity to the ring, it has long been known that the standard shepherding mechanism that works so well for Pan does not apply to these two moons. The mechanism for keeping the F ring narrow, and the roles played -- if at all -- by Prometheus and Pandora in the F ring's configuration are not well understood. This is an ongoing topic for study by Cassini scientists. This view looks toward the sunlit side of the rings from about 29 degrees above the ringplane. The image was taken in visible light with the Cassini spacecraft narrow-angle camera on Jan. 2, 2015. The view was obtained at a distance of approximately 1.6 million miles (2.6 million kilometers) from the rings and at a Sun-ring-spacecraft, or phase, angle of 86 degrees. Image scale is 10 miles (15 kilometers) per pixel. http://photojournal.jpl.nasa.gov/catalog/pia18306

Calculations of mechanisms for balance control during narrow and single-leg standing in fit older adults: A reliability study.

PubMed

Aberg, A C; Thorstensson, A; Tarassova, O; Halvorsen, K

2011-07-01

For older people balance control in standing is critical for performance of activities of daily living without falling. The aims were to investigate reliability of quantification of the usage of the two balance mechanisms M(1) 'moving the centre of pressure' and M(2) 'segment acceleration' and also to compare calculation methods based on a combination of kinetic (K) and kinematic (Km) data, (K-Km), or Km data only concerning M(2). For this purpose nine physically fit persons aged 70-78 years were tested in narrow and single-leg standing. Data were collected by a 7-camera motion capture system and two force plates. Repeated measure ANOVA and Tukey's post hoc tests were used to detect differences between the standing tasks. Reliability was estimated by ICCs, standard error of measurement including its 95% CI, and minimal detectable change, whereas Pearson's correlation coefficient was used to investigate agreement between the two calculation methods. The results indicated that for the tasks investigated, M(1) and M(2) can be measured with acceptable inter- and intrasession reliability, and that both Km and K-Km based calculations may be useful for M(2), although Km data may give slightly lower values. The proportional M(1):M(2) usage was approximately 9:1, in both anterio-posterior (AP) and medio-lateral (ML) directions for narrow standing, and about 2:1 in the AP and of 1:2 in the ML direction in single-leg standing, respectively. In conclusion, the tested measurements and calculations appear to constitute a reliable way of quantifying one important aspect of balance capacity in fit older people. Copyright © 2011 Elsevier B.V. All rights reserved.

A Colorful Look at the Birt E Crater on the Moon

NASA Image and Video Library

2014-07-17

This false color image of Birt E crater shows the topography of the moon and it is thought to be the source region for lava that carved out Rima Birt, a rille in Mare Nubium. This mare is older than 3.4 billion years, and so is this vent! LROC NAC M1144849711L/R with the a color DTM overlaid; North is up. Download high res: lroc.sese.asu.edu/posts/794 Credit: NASA/GSFC/Arizona State University More info: Birt E crater was not created like most craters on the Moon; there was no meteorite impact. Lava sputtered out of this pyroclastic vent in Mare Nubium over 3.4 billion years ago, dispersing lava onto the surface and leaving the crater we see today. How can we tell it is a volcanic vent and not an impact crater? Impact craters and volcanic vents can be differentiated because vents often have an irregular or elongated shape (as with Birt E). Impact craters are usually circular in shape, created by the shockwave during an impact event. Also, the vee-shape of this crater is likely a product of the formation mechanism. Vee-shaped vents are thought to be formed from a pyroclastic eruption. Gasses fractionating out of the liquid rock create violent events during eruptions. Explosive eruptions created the shape that we see today, but Birt E could have had a complex history with effusive eruptions forming Rima Birt, a rille flowing from Birt E to the SE. Over long enough time scales Birt E will be filled in with ejecta from newly formed craters around Mare Nubium or by mass wasting of the walls into the crater. Let’s enjoy this ancient crater today while we still can! NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

Impact of Time-of-Flight on PET Tumor Detection

PubMed Central

Kadrmas, Dan J.; Casey, Michael E.; Conti, Maurizio; Jakoby, Bjoern W.; Lois, Cristina; Townsend, David W.

2009-01-01

Time-of-flight (TOF) PET uses very fast detectors to improve localization of events along coincidence lines-of-response. This information is then utilized to improve the tomographic reconstruction. This work evaluates the effect of TOF upon an observer's performance for detecting and localizing focal warm lesions in noisy PET images. Methods An advanced anthropomorphic lesion-detection phantom was scanned 12 times over 3 days on a prototype TOF PET/CT scanner (Siemens Medical Solutions). The phantom was devised to mimic whole-body oncologic 18F-FDG PET imaging, and a number of spheric lesions (diameters 6–16 mm) were distributed throughout the phantom. The data were reconstructed with the baseline line-of-response ordered-subsets expectation-maximization algorithm, with the baseline algorithm plus point spread function model (PSF), baseline plus TOF, and with both PSF+TOF. The lesion-detection performance of each reconstruction was compared and ranked using localization receiver operating characteristics (LROC) analysis with both human and numeric observers. The phantom results were then subjectively compared to 2 illustrative patient scans reconstructed with PSF and with PSF+TOF. Results Inclusion of TOF information provides a significant improvement in the area under the LROC curve compared to the baseline algorithm without TOF data (P = 0.002), providing a degree of improvement similar to that obtained with the PSF model. Use of both PSF+TOF together provided a cumulative benefit in lesion-detection performance, significantly outperforming either PSF or TOF alone (P < 0.002). Example patient images reflected the same image characteristics that gave rise to improved performance in the phantom data. Conclusion Time-of-flight PET provides a significant improvement in observer performance for detecting focal warm lesions in a noisy background. These improvements in image quality can be expected to improve performance for the clinical tasks of detecting lesions and staging disease. Further study in a large clinical population is warranted to assess the benefit of TOF for various patient sizes and count levels, and to demonstrate effective performance in the clinical environment. PMID:19617317

MO-DE-207A-01: Impact of Statistical Weights On Detection of Low-Contrast Details in Model-Based Iterative CT Reconstruction

DOE Office of Scientific and Technical Information (OSTI.GOV)

Noo, F; Guo, Z

2016-06-15

Purpose: Penalized-weighted least-square reconstruction has become an important research topic in CT, to reduce dose without affecting image quality. Two components impact image quality in this reconstruction: the statistical weights and the use of an edge-preserving penalty term. We are interested in assessing the influence of statistical weights on their own, without the edge-preserving feature. Methods: The influence of statistical weights on image quality was assessed in terms of low-contrast detail detection using LROC analysis. The task amounted to detect and localize a 6-mm lesion with random contrast inside the FORBILD head phantom. A two-alternative forced-choice experiment was used withmore » two human observers performing the task. Reconstructions without and with statistical weights were compared, both using the same quadratic penalty term. The beam energy was set to 30keV to amplify spatial differences in attenuation and thereby the role of statistical weights. A fan-beam data acquisition geometry was used. Results: Visual inspection of images clearly showed a difference in noise between the two reconstructions methods. As expected, the reconstruction without statistical weights exhibited noise streaks. The other reconstruction appeared better in this aspect, but presented other disturbing noise patterns and artifacts induced by the weights. The LROC analysis yield the following 95-percent confidence interval for the difference in reader-averaged AUC (reconstruction without weights minus reconstruction with weights): [0.0026,0.0599]. The mean AUC value was 0.9094. Conclusion: We have investigated the impact of statistical weights without the use of edge-preserving penalty in penalized weighted least-square reconstruction. A decrease rather than increase in image quality was observed when using statistical weights. Thus, the observers were better able to cope with the noise streaks than the noise patterns and artifacts induced by the statistical weights. It may be that different results would be obtained if the penalty term was used with a pixel-dependent weight. F Noo receives research support from Siemens Healthcare GmbH.« less

Structure of Dilute Pyroclastic Density Currents During Transport, Buoyancy Reversal and Liftoff

NASA Astrophysics Data System (ADS)

Andrews, B. J.

2014-12-01

Scaled laboratory experiments provide insight into structure, entrainment and liftoff in pyroclastic density currents (PDCs). Experiments are conducted in a 8.5×6.1×2.6 m air-filled tank and comprise turbulently suspended mixtures of heated 20-μm talc particles introduced to the tank at steady and sustained rates; the tank is large enough that the currents are effectively unconfined. Experiments are scaled with bulk (densimetric and thermal Richardson numbers, Froude number) and turbulent (Stokes and settling numbers) parameters dynamically similar to natural currents. The Reynolds numbers of experiments are smaller than those of natural PDCs, but analysis of the experiments demonstrates that they are fully turbulent. Red, green, and blue laser sheets illuminate orthogonal planes within the currents for imaging and recording with HD video cameras; those data are reprojected into cross-sectional and map-view planes for analysis of turbulent velocity fields and fluctuations in particle concentration. A green laser sheet can be swept through the tank at 60 Hz and imaged with a high-speed CCD camera at up to 3000 fps; sequences of 60-300 images are used to make 3D volumetric reconstructions of the currents at up to 10 Hz. Currents typically comprise a lower "bypass" region and an upper entraining region that turbulently mixes with the ambient air. The bypass region is generally about half of the total current thickness and moves faster than the overlying, entraining region. The bypass region controls runout distance and steadiness of currents. If turbulent structures in the entraining region penetrate through the bypass region, the trailing portion of the current can stall before resuming forward progress; thus a single, "steady" current can generate multiple currents. When a current lifts off, it focuses along a narrow axis beneath the rising (coignimbrite) plume. At that time, ambient air entrainment occurs primarily through the lateral margins of the narrow bypass region. Eddies that entrain air through the lateral margins grow in size with transport distance such that at the maximum runout distance, eddies have lengthscales comparable to the current width. The largest structures within the rising plumes have lengthscales comparable to the cross-stream plume width.

Clumps in the F Ring

NASA Image and Video Library

2004-03-12

Scientists have only a rough idea of the lifetime of clumps in Saturn's rings - a mystery that Cassini may help answer. The latest images taken by the Cassini-Huygens spacecraft show clumps seemingly embedded within Saturn's narrow, outermost F ring. The narrow angle camera took the images on Feb. 23, 2004, from a distance of 62.9 million kilometers (39 million miles). The two images taken nearly two hours apart show these clumps as they revolve about the planet. The small dot at center right in the second image is one of Saturn's small moons, Janus, which is 181 kilometers, (112 miles) across. Like all particles in Saturn's ring system, these clump features orbit the planet in the same direction in which the planet rotates. This direction is clockwise as seen from Cassini's southern vantage point below the ring plane. Two clumps in particular, one of them extended, is visible in the upper part of the F ring in the image on the left, and in the lower part of the ring in the image on the right. Other knot-like irregularities in the ring's brightness are visible in the image on the right. The core of the F ring is about 50 kilometers (31miles) wide, and from Cassini's current distance, is not fully visible. The imaging team enhanced the contrast of the images and magnified them to aid visibility of the F ring and the clump features. The camera took the images with the green filter, which is centered at 568 nanometers. The image scale is 377 kilometers (234 miles) per pixel. NASA's two Voyager spacecraft that flew past Saturn in 1980 and 1981 were the first to see these clumps. The Voyager data suggest that the clumps change very little and can be tracked as they orbit for 30 days or more. No clump survived from the time of the first Voyager flyby to the Voyager 2 flyby nine months later. Scientists are not certain of the cause of these features. Among the theories proposed are meteoroid bombardments and inter-particle collisions in the F ring. http://photojournal.jpl.nasa.gov/catalog/PIA05382

Mars Orbiter Camera Views the 'Face on Mars' - Best View from Viking

NASA Technical Reports Server (NTRS)

1998-01-01

Shortly after midnight Sunday morning (5 April 1998 12:39 AM PST), the Mars Orbiter Camera (MOC) on the Mars Global Surveyor (MGS) spacecraft successfully acquired a high resolution image of the 'Face on Mars' feature in the Cydonia region. The image was transmitted to Earth on Sunday, and retrieved from the mission computer data base Monday morning (6 April 1998). The image was processed at the Malin Space Science Systems (MSSS) facility 9:15 AM and the raw image immediately transferred to the Jet Propulsion Laboratory (JPL) for release to the Internet. The images shown here were subsequently processed at MSSS.

The picture was acquired 375 seconds after the spacecraft's 220th close approach to Mars. At that time, the 'Face', located at approximately 40.8o N, 9.6o W, was 275 miles (444 km) from the spacecraft. The 'morning' sun was 25o above the horizon. The picture has a resolution of 14.1 feet (4.3 meters) per pixel, making it ten times higher resolution than the best previous image of the feature, which was taken by the Viking Mission in the mid-1970's. The full image covers an area 2.7 miles (4.4 km) wide and 25.7 miles (41.5 km) long.

This Viking Orbiter image is one of the best Viking pictures of the area Cydonia where the 'Face' is located. Marked on the image are the 'footprint' of the high resolution (narrow angle) Mars Orbiter Camera image and the area seen in enlarged views (dashed box). See PIA01440-1442 for these images in raw and processed form.

Malin Space Science Systems and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO.

Feasibility Study of Compton Cameras for X-ray Fluorescence Computed Tomography with Humans

PubMed Central

Vernekohl, Don; Ahmad, Moiz; Chinn, Garry; Xing, Lei

2017-01-01

X-ray fluorescence imaging is a promising imaging technique able to depict the spatial distributions of low amounts of molecular agents in vivo. Currently, the translation of the technique to preclinical and clinical applications is hindered by long scanning times as objects are scanned with flux-limited narrow pencil beams. The study presents a novel imaging approach combining x-ray fluorescence imaging with Compton imaging. Compton cameras leverage the imaging performance of XFCT and abolish the need of pencil beam excitation. The study examines the potential of this new imaging approach on the base of Monte-Carlo simulations. In the work, it is first presented that the particular option of slice/fan-beam x-ray excitation has advantages in image reconstruction in regard of processing time and image quality compared to traditional volumetric Compton imaging. In a second experiment, the feasibility of the approach for clinical applications with tracer agents made from gold nano-particles is examined in a simulated lung scan scenario. The high energy of characteristic x-ray photons from gold is advantageous for deep tissue penetration and has lower angular blurring in the Compton camera. It is found that Doppler broadening in the first detector stage of the Compton camera adds the largest contribution on the angular blurring; physically limiting the spatial resolution. Following the analysis of the results from the spatial resolution test, resolutions in the order of one centimeter are achievable with the approach in the center of the lung. The concept of Compton imaging allows to distinguish to some extend between scattered photons and x-ray fluorescent photons based on their difference in emission position. The results predict that molecular sensitivities down to 240 pM/l for 5 mm diameter lesions at 15 mGy for 50 nm diameter gold nano-particles are achievable. A 45-fold speed up time for data acquisition compared to traditional pencil beam XFCT could be achieved for lung imaging on cost of a small sensitivity decrease. PMID:27845933