Sample records for zorbax eclipse xdb-c8

  1. Separation and identification of corticosterone metabolites by liquid chromatography--electrospray ionization mass spectrometry.

    PubMed

    Miksík, I; Vylitová, M; Pácha, J; Deyl, Z

    1999-04-16

    High-performance liquid chromatography coupled to atmospheric pressure ionization-electrospray ionization mass spectrometry (API-ESI-MS) was investigated for the analysis of corticosterone metabolites; their characterization was obtained by combining the separation on Zorbax Eclipse XDB C18 column (eluted with a methanol-water-acetic acid gradient) with identification using positive ion mode API-ESI-MS and selected ion analysis. The applicability of this method was verified by monitoring the activity of steroid converting enzymes (20beta-hydroxysteroid dehydrogenase and 11beta-hydroxysteroid dehydrogenase) in avian intestines.

  2. Characterization of bonded stationary phase performance as a function of qualitative and quantitative chromatographic factors in chaotropic chromatography with risperidone and its impurities as model substances.

    PubMed

    Čolović, Jelena; Rmandić, Milena; Malenović, Anđelija

    2018-05-17

    Numerous stationary phases have been developed with the aim to provide desired performances during chromatographic analysis of the basic solutes in their protonated form. In this work, the procedure for the characterization of bonded stationary phase performance, when both qualitative and quantitative chromatographic factors were varied in chaotropic chromatography, was proposed. Risperidone and its three impurities were selected as model substances, while acetonitrile content in the mobile phase (20-30%), the pH of the aqueous phase (3.00-5.00), the content of chaotropic agents in the aqueous phase (10-100 mM), type of chaotropic agent (NaClO 4 , CF 3 COONa), and stationary phase type (Zorbax Eclipse XDB, Zorbax Extend) were studied as chromatographic factors. The proposed procedure implies the combination of D-optimal experimental design, indirect modeling, and polynomial-modified Gaussian model, while grid point search method was selected for the final choice of the experimental conditions which lead to the best possible stationary phase performance for basic solutes. Good agreement between experimentally obtained chromatogram and simulated chromatogram for chosen experimental conditions (25% acetonitrile, 75 mM of NaClO 4 , pH 4.00 on Zorbax Eclipse XDB column) confirmed the applicability of the proposed procedure. The additional point was selected for the verification of proposed procedure ability to distinguish changes in solutes' elution order. Simulated chromatogram for 21.5% acetonitrile, 85 mM of NaClO 4 , pH 5.00 on Zorbax Eclipse XDB column was in line with experimental data. Furthermore, the values of left and right peak half-widths obtained from indirect modeling were used in order to evaluate performances of differently modified stationary phases applying a half-width plots approach. The results from half-width plot approach as well as from the proposed procedure indicate higher efficiency and better separation performance of the stationary phase

  3. Development and validation of a simple high-performance liquid chromatography analytical method for simultaneous determination of phytosterols, cholesterol and squalene in parenteral lipid emulsions.

    PubMed

    Novak, Ana; Gutiérrez-Zamora, Mercè; Domenech, Lluís; Suñé-Negre, Josep M; Miñarro, Montserrat; García-Montoya, Encarna; Llop, Josep M; Ticó, Josep R; Pérez-Lozano, Pilar

    2018-02-01

    A simple analytical method for simultaneous determination of phytosterols, cholesterol and squalene in lipid emulsions was developed owing to increased interest in their clinical effects. Method development was based on commonly used stationary (C 18 , C 8 and phenyl) and mobile phases (mixtures of acetonitrile, methanol and water) under isocratic conditions. Differences in stationary phases resulted in peak overlapping or coelution of different peaks. The best separation of all analyzed compounds was achieved on Zorbax Eclipse XDB C 8 (150 × 4.6 mm, 5 μm; Agilent) and ACN-H 2 O-MeOH, 80:19.5:0.5 (v/v/v). In order to achieve a shorter time of analysis, the method was further optimized and gradient separation was established. The optimized analytical method was validated and tested for routine use in lipid emulsion analyses. Copyright © 2017 John Wiley & Sons, Ltd.

  4. Application of liquid chromatography-electrospray ionization mass spectrometry for study of steroid-converting enzymes.

    PubMed

    Miksík, Ivan; Mikulíková, Katerina; Pácha, Jirí; Kucka, Marek; Deyl, Zdenek

    2004-02-05

    A high-performance liquid chromatography-atmospheric pressure ionization-electrospray ionization mass spectrometry (HPLC-API-ESI-MS) method was developed for the analysis of steroids in a study of steroid-converting enzymes. Separations ware done on a Zorbax Eclipse XDB-C18 column (eluted with a linear methanol-water-acetic acid gradient) and identification of the steroids involved was done by API-ESI-MS using positive ion mode and extracted ion analysis. The applicability of the present method for studying steroid metabolism was proven in assaying two steroid-converting enzymes (20beta-hydroxysteroid dehydrogenase and 11beta-hydroxysteroid dehydrogenase) in various biological samples (rat and chicken intestine, chicken oviduct).

  5. Authentication and Quantitation of Fraud in Extra Virgin Olive Oils Based on HPLC-UV Fingerprinting and Multivariate Calibration

    PubMed Central

    Carranco, Núria; Farrés-Cebrián, Mireia; Saurina, Javier

    2018-01-01

    High performance liquid chromatography method with ultra-violet detection (HPLC-UV) fingerprinting was applied for the analysis and characterization of olive oils, and was performed using a Zorbax Eclipse XDB-C8 reversed-phase column under gradient elution, employing 0.1% formic acid aqueous solution and methanol as mobile phase. More than 130 edible oils, including monovarietal extra-virgin olive oils (EVOOs) and other vegetable oils, were analyzed. Principal component analysis results showed a noticeable discrimination between olive oils and other vegetable oils using raw HPLC-UV chromatographic profiles as data descriptors. However, selected HPLC-UV chromatographic time-window segments were necessary to achieve discrimination among monovarietal EVOOs. Partial least square (PLS) regression was employed to tackle olive oil authentication of Arbequina EVOO adulterated with Picual EVOO, a refined olive oil, and sunflower oil. Highly satisfactory results were obtained after PLS analysis, with overall errors in the quantitation of adulteration in the Arbequina EVOO (minimum 2.5% adulterant) below 2.9%. PMID:29561820

  6. High-performance liquid chromatographic determination of pantoprazole and its main impurities in pharmaceuticals.

    PubMed

    Letica, Jelena; Marković, Slavko; Zirojević, Jelena; Nikolić, Katarina; Agbaba, Danica

    2010-01-01

    An RP-HPLC method for simultaneous separation and quantification of pantoprazole and its five main impurities in pharmaceutical formulations was developed and validated. The separation was accomplished on a Zorbax Eclipse XDB C18 column (5 microm particle size, 150 x 4.6 mm id) using a gradient with mobile phase A [buffer-acetonitrile (70 + 30, v/v)], and mobile phase B [buffer-acetonitrile (30 + 70, v/v)]. The buffer was 0.01 M ammonium acetate solution with addition of 1 mL triethylamine/L of the solution, adjusted to pH 4.5 with orthophosphoric acid. The eluent flow rate was 1 mL/min, the temperature of the column was 30 degrees C, and the eluate was monitored at 290 nm. Linearity (r = 0.999), recovery (97.6-105.8%), RSD (0.55-1.90%), and LOQ (0.099-1.48 microg/mL) were evaluated and found to be satisfactory. The proposed method can be used for simultaneous identification and quantification of the analyzed compounds in pharmaceutical formulations.

  7. [Determination of four alkaloids in Corydalis decumbens by HPLC].

    PubMed

    Shen, Yan; Han, Chao; Xia, Biqi; Zhou, Yongfang; Liu, Cuiping; Liu, Aili

    2011-08-01

    To establish a quantitative HPLC method for determination of protopine, palmatine hydrochloride, bicuculline and tetrahydropalmatine, in Corydalis decumbens. The separation was performed on a ZORBAX Eclipse XDB-C18 column (4.6 mm x 150 mm, 5 microm) at a flow rate of 1.0 mL x min(-1) using mixtures of two solvents [A(20 mmol x L(-1) ammonium acetate)-B(acetonitrile)]: with a gradient elution. The column oven temperature was 30 degrees C and the detection wavelength was set at 280 nm. The 4 alkaloids were well separated by this HPLC method. Linearifies of protopine, palmatine hydrochloride, bicuculline and tetrahydropalmatine were good in the ranges of 1.44-46.0 (r = 0.999 4), 1.2640.2 (r = 0.999 8), 1.37-44.0 (r = 0.999 9), and 1.3643.6 mg x L(-1) (r = 0.999 9), respectively. The average recoveries were 98.2% with RSD 2.7% for protopine, 101.9% with RSD 2.5% for palmatine hydrochloride, 102.8% with RSD 3.5% for tetrahydropalmatine, and 98.8% with RSD 3.1% for tetrahydropalmatine. This method is proved to be convenient, reliable and accurate., and it can be used for quality control of C. decumbens.

  8. Green Chromatographic Separation of Coumarin and Vanillins Using Subcritical Water as the Mobile Phase.

    PubMed

    Kayan, Berkant; Akay, Sema; Yang, Yu

    2016-08-01

    Pure water was used as the eluent for separation of coumarin, vanillin and ethyl vanillin at temperatures ranging from 100 to 200°C using a homemade subcritical water chromatography (SBWC) system. Chromatographic separations were performed on five commercial columns including XTerra MS C18, XBridge C18, Zorbax RRHD Eclipse Plus, Zorbax SB-Phenyl and Zorbax SB-C18 columns. The retention time of all three solutes decreased with increasing water temperature. The shortest retention time among all acceptable separations, less than 4 min, was achieved on the Zorbax SB-C18 column at 200°C. While separations on the XTerra MS C18 column resulted in fronting peaks and a degradation peak from ethyl vanillin on the Zorbax RRHD Eclipse Plus column was observed, all three other columns yielded reasonable separations under SBWC conditions. In addition to separation of the standard test mixture, separation of coumarin contained in a skincare cream sample was also carried out using SBWC. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  9. Eclipse program C-141A aircraft

    NASA Technical Reports Server (NTRS)

    1997-01-01

    This photograph shows the Air Force C-141A that was used in the Eclipse project as a tow vehicle. In 1997 and 1998, the Dryden Flight Research Center at Edwards, California, supported and hosted a Kelly Space & Technology, Inc. project called Eclipse, which sought to demonstrate the feasibility of a reusable tow-launch vehicle concept. The project goal was to successfully tow, inflight, a modified QF-106 delta-wing aircraft with an Air Force C-141A transport aircraft. This would demonstrate the possibility of towing and launching an actual launch vehicle from behind a tow plane. Dryden was the responsible test organization and had flight safety responsibility for the Eclipse project. Dryden provided engineering, instrumentation, simulation, modification, maintenance, range support, and research pilots for the test program. The Air Force Flight Test Center (AFFTC), Edwards, California, supplied the C-141A transport aircraft and crew and configured the aircraft as needed for the tests. The AFFTC also provided the concept and detail design and analysis as well as hardware for the tow system and QF-106 modifications. Dryden performed the modifications to convert the QF-106 drone into the piloted EXD-01 (Eclipse eXperimental Demonstrator-01) experimental aircraft. Kelly Space & Technology hoped to use the results gleaned from the tow test in developing a series of low-cost, reusable launch vehicles. These tests demonstrated the validity of towing a delta-wing aircraft having high wind loading, validated the tow simulation model, and demonstrated various operational procedures, such as ground processing of in-flight maneuvers and emergency abort scenarios.

  10. Eclipse program C-141A aircraft

    NASA Technical Reports Server (NTRS)

    1997-01-01

    This photograph shows the Air Force C-141A that was used in the Eclipse project as a tow vehicle. The project used a QF-106 interceptor aircraft to simulate a future orbiter, which would be towed to a high altitude and released to fire its own engines and carry a payload into space. In 1997 and 1998, the Dryden Flight Research Center at Edwards, California, supported and hosted a Kelly Space & Technology, Inc. project called Eclipse, which sought to demonstrate the feasibility of a reusable tow-launch vehicle concept. The project goal was to successfully tow, inflight, a modified QF-106 delta-wing aircraft with an Air Force C-141A transport aircraft. This would demonstrate the possibility of towing and launching an actual launch vehicle from behind a tow plane. Dryden was the responsible test organization and had flight safety responsibility for the Eclipse project. Dryden provided engineering, instrumentation, simulation, modification, maintenance, range support, and research pilots for the test program. The Air Force Flight Test Center (AFFTC), Edwards, California, supplied the C-141A transport aircraft and crew and configured the aircraft as needed for the tests. The AFFTC also provided the concept and detail design and analysis as well as hardware for the tow system and QF-106 modifications. Dryden performed the modifications to convert the QF-106 drone into the piloted EXD-01 (Eclipse eXperimental Demonstrator-01) experimental aircraft. Kelly Space & Technology hoped to use the results gleaned from the tow test in developing a series of low-cost, reusable launch vehicles. These tests demonstrated the validity of towing a delta-wing aircraft having high wing loading, validated the tow simulation model, and demonstrated various operational procedures, such as ground processing of in-flight maneuvers and emergency abort scenarios.

  11. [Simultaneous determination of canthaxanthin and astaxanthin in feedstuffs using solid phase extraction-reversed-phase high performance liquid chromatography].

    PubMed

    Zhang, Hua; Yang, Xin; Ma, Ying; Dong, Aijun; Zhang, Yingchun

    2008-05-01

    A method was developed for the simultaneous determination of canthaxanthin and astaxanthin in feedstuffs using reversed-phase high performance liquid chromatography (RP-HPLC). The sample was extracted by acetonitrile, and cleaned up by an LC-NH2 column. An Agilent ZORBAX Eclipse XDB-C18 analytical column (150 mm x 4.6 mm, 5 microm) was used and kept at 25 degrees C. Acetonitrile-methanol (95 : 5, v/v) was used as the mobile phase at a flow rate of 1.0 mL/min. The detection was performed by a diode array detector at 474 nm. The quantitive analysis of external standard calibration curves was used. The linear ranges of the method for canthaxanthin and astaxanthin were 1.0 - 30.0 mg/L (r = 0.999 0) and 1.0 - 20.0 mg/L (r = 0.999 1), respectively. The average recoveries were 90% - 101% with the relative standard deviations of 0.62% - 3.68%. The detection limits were 0.84 and 0.60 mg/L for canthaxanthin and astaxanthin, respectively. The method is simple, precise, sensitive and reproductive. It can be used to determine the contents of canthaxanthin and astaxanthin in feedstuffs.

  12. The Xeno-glycomics database (XDB): a relational database of qualitative and quantitative pig glycome repertoire.

    PubMed

    Park, Hae-Min; Park, Ju-Hyeong; Kim, Yoon-Woo; Kim, Kyoung-Jin; Jeong, Hee-Jin; Jang, Kyoung-Soon; Kim, Byung-Gee; Kim, Yun-Gon

    2013-11-15

    In recent years, the improvement of mass spectrometry-based glycomics techniques (i.e. highly sensitive, quantitative and high-throughput analytical tools) has enabled us to obtain a large dataset of glycans. Here we present a database named Xeno-glycomics database (XDB) that contains cell- or tissue-specific pig glycomes analyzed with mass spectrometry-based techniques, including a comprehensive pig glycan information on chemical structures, mass values, types and relative quantities. It was designed as a user-friendly web-based interface that allows users to query the database according to pig tissue/cell types or glycan masses. This database will contribute in providing qualitative and quantitative information on glycomes characterized from various pig cells/organs in xenotransplantation and might eventually provide new targets in the α1,3-galactosyltransferase gene-knock out pigs era. The database can be accessed on the web at http://bioinformatics.snu.ac.kr/xdb.

  13. Vigabatrin in dried plasma spots: validation of a novel LC-MS/MS method and application to clinical practice.

    PubMed

    Kostić, Nađa; Dotsikas, Yannis; Jović, Nebojša; Stevanović, Galina; Malenović, Anđelija; Medenica, Mirjana

    2014-07-01

    This paper presents a LC-MS/MS method for the determination of antiepileptic drug vigabatrin in dried plasma spots (DPS). Due to its zwitterionic chemical structure, a pre-column derivatization procedure was performed, aiming to yield enhanced ionization efficiency and improved chromatographic behaviour. Propyl chloroformate, in the presence of propanol, was selected as the best derivatization reagent, providing a strong signal along with reasonable run time. A relatively novel sample collection technique, DPS, was utilized, offering easy sample handling and analysis, using a sample in micro amount (∼5μL). Derivatized vigabatrin and its internal standard, 4-aminocyclohexanecarboxylic acid, were extracted by liquid-liquid extraction (LLE) and determined in positive ion mode by applying two SRM transitions per analyte. A Zorbax Eclipse XDB-C8 column (150×4.6mm, 5μm particle size) maintained at 30°C, was utilized with running mobile phase composed of acetonitrile: 0.15% formic acid (85:15, v/v). Flow rate was 550μL/min and total run time 4.5min. The assay exhibited excellent linearity over the concentration range of 0.500-50.0μg/mL, which is suitable for the determination of vigabatrin level after per os administration in children and youths with epilepsy, who were on vigabatrin therapy, with or without co-medication. Specificity, accuracy, precision, recovery, matrix-effect and stability were also estimated and assessed within acceptance criteria. Copyright © 2014 Elsevier B.V. All rights reserved.

  14. A simple, fast and sensitive screening LC-ESI-MS/MS method for antibiotics in fish.

    PubMed

    Guidi, Letícia Rocha; Santos, Flávio Alves; Ribeiro, Ana Cláudia S R; Fernandes, Christian; Silva, Luiza H M; Gloria, Maria Beatriz A

    2017-01-15

    The objective of this study was to develop and validate a fast, sensitive and simple liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS) method for the screening of six classes of antibiotics (aminoglycosides, beta-lactams, macrolides, quinolones, sulfonamides and tetracyclines) in fish. Samples were extracted with trichloroacetic acid. LC separation was achieved on a Zorbax Eclipse XDB C18 column and gradient elution using 0.1% heptafluorobutyric acid in water and acetonitrile as mobile phase. Analysis was carried out in multiple reaction monitoring mode via electrospray interface operated in the positive ionization mode, with sulfaphenazole as internal standard. The method was suitable for routine screening purposes of 40 antibiotics, according to EC Guidelines for the Validation of Screening Methods for Residues of Veterinary Medicines, taking into consideration threshold value, cut-off factor, detection capability, limit of detection, sensitivity and specificity. Real fish samples (n=193) from aquaculture were analyzed and 15% were positive for enrofloxacin (quinolone), one of them at a higher concentration than the level of interest (50µgkg -1 ), suggesting possible contamination or illegal use of that antibiotic. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. Quantitation of the immunological adjuvants, monophosphoryl lipid A and Quil A in poly (lactic-co-glycolic acid) nanoparticles using high performance liquid chromatography with evaporative light scattering detection.

    PubMed

    Bobbala, Sharan; McDowell, Arlene; Hook, Sarah

    2015-01-15

    Monophosphoryl lipid A (MPL) and Quil A are two immunological adjuvants commonly used in vaccines. At present no simple, validated methods for the quantification of Quil A and MPL have been previously reported therefore the aim of the current study was to develop a simple, fast and validated method to quantify MPL and Quil A using high performance liquid chromatography evaporative light scattering detection (HPLC-ELSD). The HPLC-ELSD technique was carried out using a ZORBAX Eclipse XDB-C8 column (2.1×50 mm; particle size, 3.5 μm) in an isocratic elution mode at 25 °C. MPL was eluted at a retention time of 1.8 min with methanol-water as the mobile phase and a detector temperature of 75 °C. Quil A was resolved as three peaks with retention times of 4.1, 5.5 and 6.4 min with a detector temperature of 30 °C and with water-acetonitrile and 0.01% formic acid as the mobile phase. The nebulizer pressure and gain were set at 3.5 bar and 10, respectively. Calibration curves plotted for both the adjuvants had an R(2)>0.997. Accuracy, intra- and inter-day precision were within the accepted limits. The limit of detection for MPL and Quil A were calculated as 1.343 and 2.06 μg/mL, respectively. The limit of quantification was 2.445 for MPL and 8.97 μg/mL for Quil A. This analytical method was used to quantify the entrapment and in vitro release of MPL and Quil A in a poly lactic-co-glycolic acid (PLGA) nanoparticle vaccine. Copyright © 2014 Elsevier B.V. All rights reserved.

  16. Simultaneous determination of five free and total flavonoids in rat plasma by ultra HPLC-MS/MS and its application to a comparative pharmacokinetic study in normal and hyperlipidemic rats.

    PubMed

    Wang, Xiaofan; Zhao, Xu; Gu, Liqiang; Lv, Chunxiao; He, Bosai; Liu, Zhenzhen; Hou, Pengyi; Bi, Kaishun; Chen, Xiaohui

    2014-03-15

    A simple and rapid ultra-high performance liquid chromatography-tandem mass spectrometry (uHPLC-MS/MS) method has been developed for the simultaneous determination of five free flavonoids (amentoflavone, isorhamnetin, naringenin, kaempferol and quercetin) and their total (free and conjugated) forms, and to compare the pharmacokinetics of these active ingredients in normal and hyperlipidemic rats. The free and total forms of these flavonoids were extracted by liquid-liquid extraction with ethyl acetate. The conjugated flavonoids were deconjugated by the enzyme β-Glucuronidase and Sulfatase. Chromatographic separation was accomplished on a ZORBAX Eclipse XDB-C8 USP L7 column using gradient elution. Detection was performed on a 4000Q uHPLC-MS/MS system from AB Sciex using negative ion mode in the multiple reaction monitoring (MRM) mode. The lower limits of quantification were 2.0-5.0ng/mL for all the analytes. Intra-day and inter-day precision were less than 15% and accuracy ranged from -9.3% to 11.0%, and the mean extraction recoveries of analytes and internal standard (IS) from rat plasma were all more than 81.7%. The validated method was successfully applied to a comparative pharmacokinetic study of five free and total analytes in rat plasma. The results indicated that the absorption of five total flavonoids in hyperlipidemia group were significantly higher than those in normal group with similar concentration-time curves. Copyright © 2014 Elsevier B.V. All rights reserved.

  17. Rapid and sensitive ultra-high-pressure liquid chromatography-tandem mass spectrometry analysis of the novel anticancer agent PR-104 and its major metabolites in human plasma: Application to a pharmacokinetic study.

    PubMed

    Gu, Yongchuan; Wilson, William R

    2009-10-01

    PR-104 is a dinitrobenzamide mustard currently in clinical trial as a hypoxia-activated prodrug. It is converted systemically to the corresponding alcohol, PR-104A, which is activated by nitroreduction to the hydroxylamine (PR-104H) and amine (PR-104M). PR-104A is also metabolised to the O-glucuronide (PR-104G), and by oxidative debromoethylation to the semi-mustard PR-104S. We now report a validated ultra-high-pressure liquid chromatography and tandem mass spectrometry (UHPLC-MS/MS) method for the determination of these metabolites in human plasma. Plasma proteins were precipitated with acidified methanol and the supernatant diluted into water. Aliquots were analysed by UHPLC-MS/MS using a Zorbax Eclipse XDB-C18 Rapid Resolution HT (50mmx2.1mm, 1.8microm) column and gradient of acetonitrile and 0.01% formic acid with a 6min run time. The method had a linear range of 0.1-50microM for PR-104, PR-104A and PR-104G, 0.05-5microM for PR-104H, 0.025-2.5microM for PR-104M and 0.01-1microM for PR-104S. The intra-day and inter-day precision and accuracy were within 14%. The extraction recovery of all analytes was over 87%. The validated method was illustrated by using it to study the pharmacokinetics of PR-104 and its metabolites in a human patient.

  18. solar eclipse 2016

    NASA Image and Video Library

    2017-12-08

    NASA TV video from yesterday's total solar eclipse, when the moon pass directly in front of the sun. It happened from 8:38 to 8:42 p.m. EST March 8. As the moon passed precisely between the sun and Earth – a relatively rare occurrence that happens only about once a year because of the fact that the moon and the sun do not orbit in the exact same plane – it blocked the sun’s bright face, revealing the tenuous and comparatively faint solar atmosphere, the corona. The total eclipse was only visible in parts of Southeast Asia Learn more about this event: youtu.be/MQjPFwcjh9c ‪ 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 ‬

  19. Application of high performance liquid chromatography for the profiling of complex chemical mixtures with the aid of chemometrics.

    PubMed

    Ni, Yongnian; Zhang, Liangsheng; Churchill, Jane; Kokot, Serge

    2007-06-15

    In this paper, chemometrics methods were applied to resolve the high performance liquid chromatography (HPLC) fingerprints of complex, many-component substances to compare samples from a batch from a given manufacturer, or from those of different producers. As an example of such complex substances, we used a common Chinese traditional medicine, Huoxiang Zhengqi Tincture (HZT) for this research. Twenty-one samples, each representing a separate HZT production batch from one of three manufacturers were analyzed by HPLC with the aid of a diode array detector (DAD). An Agilent Zorbax Eclipse XDB-C18 column with an Agilent Zorbax high pressure reliance cartridge guard-column were used. The mobile phase consisted of water (A) and methanol (B) with a gradient program of 25-65% (v/v, B) during 0-30min, 65-55% (v/v, B) during 30-35min and 55-100% (v/v, B) during 35-60min (flow rate, 1.0mlmin(-1); injection volume, 20mul; and column temperature-ambient). The detection wavelength was adjusted for maximum sensitivity at different time periods. A peak area matrix with 21objectsx14HPLC variables was obtained by sampling each chromatogram at 14 common retention times. Similarities were then calculated to discriminate the batch-to-batch samples and also, a more informative multi-criteria decision making methodology (MCDM), PROMETHEE and GAIA, was applied to obtain more information from the chromatograms in order to rank and compare the complex HZT profiles. The results showed that with the MCDM analysis, it was possible to match and discriminate correctly the batch samples from the three different manufacturers. Fourier transform infrared (FT-IR) spectra taken from samples from several batches were compared by the common similarity method with the HPLC results. It was found that the FT-IR spectra did not discriminate the samples from the different batches.

  20. How Accurately Can We Predict Eclipses for Algol? (Poster abstract)

    NASA Astrophysics Data System (ADS)

    Turner, D.

    2016-06-01

    (Abstract only) beta Persei, or Algol, is a very well known eclipsing binary system consisting of a late B-type dwarf that is regularly eclipsed by a GK subgiant every 2.867 days. Eclipses, which last about 8 hours, are regular enough that predictions for times of minima are published in various places, Sky & Telescope magazine and The Observer's Handbook, for example. But eclipse minimum lasts for less than a half hour, whereas subtle mistakes in the current ephemeris for the star can result in predictions that are off by a few hours or more. The Algol system is fairly complex, with the Algol A and Algol B eclipsing system also orbited by Algol C with an orbital period of nearly 2 years. Added to that are complex long-term O-C variations with a periodicity of almost two centuries that, although suggested by Hoffmeister to be spurious, fit the type of light travel time variations expected for a fourth star also belonging to the system. The AB sub-system also undergoes mass transfer events that add complexities to its O-C behavior. Is it actually possible to predict precise times of eclipse minima for Algol months in advance given such complications, or is it better to encourage ongoing observations of the star so that O-C variations can be tracked in real time?

  1. [Determination of carcinogenic aromatic amines derived from azo colorants in plastic components of electrical and electronic products by high performance liquid chromatography-mass spectrometry].

    PubMed

    Niu, Zengyuan; Luo, Xin; Ye, Xiwen; Wang, Huihui; Li, Jingying

    2014-01-01

    A study for the simultaneous determination of 21 primary aromatic amines derived from the reduction of the azo colorants in plastic components of electrical and electronic products was conducted. Organic solvents were used to dissolve or swell the plastics to release the azo dyes existing in the plastic components. The azo colorants were reduced to aromatic amines under strong reducing condition of dithionite. Aromatic amines were extracted with methyl tert-butyl ether. Methanol-water (1: 1, v/v) was used to concentrate the extract to constant-volume for HPLC-MS analysis. The analytes were separated on a ZORBAX Eclipse XDB C18 column using the gradient elution with acetonitrile and 0.1% (v/v) formic acid aqueous solution at a flow rate of 0.6 mL/min. The analyte confirmation was performed using retention time and characteristic ions in selected ion monitoring (SIM) mode. The correlation coefficients (r) of all the standard curves were more than 0.998, and the limits of quantification of the analytes were 0.5 mg/kg. The recoveries were 60.1% - 129.5% for the 21 aromatic amines with the RSDs not more than 14.0% except for a few compounds. The results showed that the banned azo colorants in the plastic products can be analyzed qualitatively and quantitatively through reductive conversion into aromatic amines. In addition, this method has high accuracy and good precision.

  2. Is an eclipse described in the Odyssey?

    PubMed

    Baikouzis, Constantino; Magnasco, Marcelo O

    2008-07-01

    Plutarch and Heraclitus believed a certain passage in the 20th book of the Odyssey ("Theoclymenus's prophecy") to be a poetic description of a total solar eclipse. In the late 1920s, Schoch and Neugebauer computed that the solar eclipse of 16 April 1178 B.C.E. was total over the Ionian Islands and was the only suitable eclipse in more than a century to agree with classical estimates of the decade-earlier sack of Troy around 1192-1184 B.C.E. However, much skepticism remains about whether the verses refer to this, or any, eclipse. To contribute to the issue independently of the disputed eclipse reference, we analyze other astronomical references in the Epic, without assuming the existence of an eclipse, and search for dates matching the astronomical phenomena we believe they describe. We use three overt astronomical references in the epic: to Boötes and the Pleiades, Venus, and the New Moon; we supplement them with a conjectural identification of Hermes's trip to Ogygia as relating to the motion of planet Mercury. Performing an exhaustive search of all possible dates in the span 1250-1115 B.C., we looked to match these phenomena in the order and manner that the text describes. In that period, a single date closely matches our references: 16 April 1178 B.C.E. We speculate that these references, plus the disputed eclipse reference, may refer to that specific eclipse.

  3. Is an eclipse described in the Odyssey?

    PubMed Central

    Baikouzis, Constantino; Magnasco, Marcelo O.

    2008-01-01

    Plutarch and Heraclitus believed a certain passage in the 20th book of the Odyssey (“Theoclymenus's prophecy”) to be a poetic description of a total solar eclipse. In the late 1920s, Schoch and Neugebauer computed that the solar eclipse of 16 April 1178 B.C.E. was total over the Ionian Islands and was the only suitable eclipse in more than a century to agree with classical estimates of the decade-earlier sack of Troy around 1192–1184 B.C.E. However, much skepticism remains about whether the verses refer to this, or any, eclipse. To contribute to the issue independently of the disputed eclipse reference, we analyze other astronomical references in the Epic, without assuming the existence of an eclipse, and search for dates matching the astronomical phenomena we believe they describe. We use three overt astronomical references in the epic: to Boötes and the Pleiades, Venus, and the New Moon; we supplement them with a conjectural identification of Hermes's trip to Ogygia as relating to the motion of planet Mercury. Performing an exhaustive search of all possible dates in the span 1250–1115 B.C., we looked to match these phenomena in the order and manner that the text describes. In that period, a single date closely matches our references: 16 April 1178 B.C.E. We speculate that these references, plus the disputed eclipse reference, may refer to that specific eclipse. PMID:18577587

  4. Mechanism of adsorption and eclipse of bacteriophage phi X174. I. In vitro conformational change under conditions of eclipse.

    PubMed

    Incardona, N L; Blonski, R; Feeney, W

    1972-01-01

    Bacteriophage phiX174 undergoes a conformational change during viral eclipse when virus-host cell complexes are incubated briefly at 37 C in a complex starvation buffer at pH 8. In this report, basically the same transition is demonstrated in vitro. Incubation of phiX alone for 2 to 3 hr at 35 C in 0.1 m CaCl(2) (pH 7.2) results in an irreversible decrease in S(20,w) because of an increase in the frictional coefficient that occurs during the change in conformation. The slower sedimenting conformation is noninfectious. These properties are remarkably similar to those of the eclipsed particles characterized by Newbold and Sinsheimer. Therefore, the key structural requirements for the molecular mechanism must reside within the architecture of the virus itself. This extremely simplified system uncovered the calcium ion requirement and pronounced dependence on pH between 6 and 7, both inherent properties of adsorption. This and the more than 10-fold greater rate of the in vivo conformational transition allude to the cooperative nature of attachment and eclipse for phiX.

  5. Searching Planets Around Some Selected Eclipsing Close Binary Stars Systems

    NASA Astrophysics Data System (ADS)

    Nasiroglu, Ilham; Slowikowska, Agnieszka; Krzeszowski, Krzysztof; Zejmo, M. Michal; Er, Hüseyin; Goździewski, Krzysztof; Zola, Stanislaw; Koziel-Wierzbowska, Dorota; Debski, Bartholomew; Ogloza, Waldemar; Drozdz, Marek

    2016-07-01

    We present updated O-C diagrams of selected short period eclipsing binaries observed since 2009 with the T100 Telescope at the TUBITAK National Observatory (Antalya, Turkey), the T60 Telescope at the Adiyaman University Observatory (Adiyaman, Turkey), the 60cm at the Mt. Suhora Observatory of the Pedagogical University (Poland) and the 50cm Cassegrain telescope at the Fort Skala Astronomical Observatory of the Jagiellonian University in Krakow, Poland. All four telescopes are equipped with sensitive, back-illuminated CCD cameras and sets of wide band filters. One of the targets in our sample is a post-common envelope eclipsing binary NSVS 14256825. We collected more than 50 new eclipses for this system that together with the literature data gives more than 120 eclipse timings over the time span of 8.5 years. The obtained O-C diagram shows quasi-periodic variations that can be well explained by the existence of the third body on Jupiter-like orbit. We also present new results indicating a possible light time travel effect inferred from the O-C diagrams of two other binary systems: HU Aqr and V470 Cam.

  6. David Levy's Guide to Eclipses, Transits, and Occultations

    NASA Astrophysics Data System (ADS)

    Levy, David H.

    2010-08-01

    Introduction; Part I. The Magic and History of Eclipses: 1. Shakespeare, King Lear, and the Great Eclipse of 1605; 2. Three centuries later: Einstein, relativity, and the solar eclipse of 1919; 3. What causes solar and lunar eclipses; Part II. Observing Solar Eclipses: 4. Safety considerations; 5. What to expect during a partial eclipse; 6. Annular eclipses and what to see in them; 7. Total eclipse of the Sun: introduction to the magic; 8. The onset: temperature drop, Baily's Beads, Diamond Ring; 9. Totality: Corona, Prominences, Chromosphere, and surrounding area; 10. Photographing and imaging a solar eclipse; Part III. Observing Lunar Eclipses: 11. Don't forget the penumbral eclipses!; 12. Partial lunar eclipses; 13. Total lunar eclipses; 14. Photographing and imaging lunar eclipses; Part IV. Occultations: 15. When the Moon occults a star; Part V. Transits: 16. When planets cross the Sun; Part VI. My Favorite Eclipses: 17. A personal canon of eclipses, occultations, and transits I have seen; Appendices; Index.

  7. Solar Eclipse Effect on Shelter Air Temperature

    NASA Technical Reports Server (NTRS)

    Segal, M.; Turner, R. W.; Prusa, J.; Bitzer, R. J.; Finley, S. V.

    1996-01-01

    Decreases in shelter temperature during eclipse events were quantified on the basis of observations, numerical model simulations, and complementary conceptual evaluations. Observations for the annular eclipse on 10 May 1994 over the United States are presented, and these provide insights into the temporal and spatial changes in the shelter temperature. The observations indicated near-surface temperature drops of as much as 6 C. Numerical model simulations for this eclipse event, which provide a complementary evaluation of the spatial and temporal patterns of the temperature drops, predict similar decreases. Interrelationships between the temperature drop, degree of solar irradiance reduction, and timing of the peak eclipse are also evaluated for late spring, summer, and winter sun conditions. These simulations suggest that for total eclipses the drops in shelter temperature in midlatitudes can be as high as 7 C for a spring morning eclipse.

  8. Development of anion-exchange/reversed-phase high performance liquid chromatography-inductively coupled plasma-mass spectrometry methods for the speciation of bio-available iodine and bromine from edible seaweed.

    PubMed

    Romarís-Hortas, Vanessa; Bermejo-Barrera, Pilar; Moreda-Piñeiro, Antonio

    2012-05-04

    Anion exchange high performance liquid chromatography hyphenated with inductively coupled plasma-mass spectrometry has been novelly applied to assess inorganic (iodide and iodate) and organic (3-iodotyrosine - MIT, and 3,5-diiodotyrosine - DIT) iodine species in a single chromatographic run. The optimized operating conditions (Dionex IonPac AS7, gradient elution with 175 mM ammonium nitrate plus 15% (v/v) methanol, pH 3.8, as a mobile phase and flow rates within the 0.5-1.5 mL min(-1) range) have also been used to perform inorganic bromine speciation analysis (bromide and bromate). The developed method has been applied for determining the bio-available contents of iodine and bromine species in dialyzates from edible seaweed. Reverse phase high performance liquid chromatography (Zorbax Eclipse XDB-C8, gradient elution with 0.2% (m/m) acetic acid, and 0.2% (m/m) acetic acid in methanol, as mobile phases, and a constant flow rate of 0.75 mL min(-1)) also hyphenated with inductively coupled plasma-mass spectrometry was used to confirm the presence of organic iodine species (MIT and DIT) in the dialyzates. The verification of the presence of iodinated amino acids (MIT and DIT) in the extracts was also performed by reverse phase high performance liquid chromatography-electrospray ionization-mass spectrometry (LTQ Orbitrap). The developed methods have provided good repeatability (RSD values lower than 10% for both anion exchange and reverse phase separations) and analytical recoveries within the 90-105% range for all cases. The in vitro bio-availability method consisted of a simulated gastric and an intestinal digestion/dialysis (10 kDa molecular weight cut-off - MWCO) two-stage procedure. Iodide and MIT were the main bio-available species quantified, whereas bromide was the major bromine species found in the extracts. Copyright © 2012 Elsevier B.V. All rights reserved.

  9. HPLC-FLD determination of 4-nonylphenol and 4-tert-octylphenol in surface water samples.

    PubMed

    Cruceru, Ioana; Iancu, Vasile; Petre, Jana; Badea, Irinel Adriana; Vladescu, Luminita

    2012-05-01

    A simple, sensitive and reliable HPLC-FLD method for the routine determination of 4-nonylphenol, 4-NP and 4-tert-octylphenol, 4-t-OP content in water samples was developed. The method consists in a liquid-liquid extraction of the target analytes with dichloromethane at pH  3.0-3.5 followed by the HPLC-FLD analysis of the organic extract using a Zorbax Eclipse XDB C8 column, isocratic elution with a mixed solvent acetonitrile/water 65:35, at a flow rate of 1.0 mL/min and applying a column temperature of 40°C. The method was validated and then applied with good results for the determination of 4-NP and 4-t-OP in Ialomiţa River water samples collected each month during 2006. The concentration levels of 4-NP and 4-t-OP vary between 0.08-0.17 μg/L with higher values of 0.24-0.37 μg/L in the summer months for 4-NP, and frequently <0.05 μg/L but also between 0.06-0.09 μg/L with higher values of 0.12-0.16 μg/L in July and August for 4-t-OP and were strongly influenced by sesonial and anthropic factors. The method was also applied on samples collected over 2 years 2007 and 2008 from urban wastewaters discharged into sewage or directly into the rivers by economic agents located in 30 Romanian towns. Good results were obtained when the method was used for analysis of effluents discharged into surface waters by 16 municipal wastewater treatment plants, during the year 2008.

  10. A validated stability-indicating HPLC method for determination of varenicline in its bulk and tablets

    PubMed Central

    2011-01-01

    A simple, sensitive and accurate stability-indicating HPLC method has been developed and validated for determination of varenicline (VRC) in its bulk form and pharmaceutical tablets. Chromatographic separation was achieved on a Zorbax Eclipse XDB-C8 column (150 mm × 4.6 mm i.d., particle size 5 μm, maintained at ambient temperature) by a mobile phase consisted of acetonitrile and 50 mM potassium dihydrogen phosphate buffer (10:90, v/v) with apparent pH of 3.5 ± 0.1 and a flow rate of 1.0 ml/min. The detection wavelength was set at 235 nm. VRC was subjected to different accelerated stress conditions. The degradation products, when any, were well resolved from the pure drug with significantly different retention time values. The method was linear (r = 0.9998) at a concentration range of 2 - 14 μg/ml. The limit of detection and limit of quantitation were 0.38 and 1.11 μg/ml, respectively. The intra- and inter-assay precisions were satisfactory; the relative standard deviations did not exceed 2%. The accuracy of the method was proved; the mean recovery of VRC was 100.10 ± 1.08%. The proposed method has high throughput as the analysis involved short run-time (~ 6 min). The method met the ICH/FDA regulatory requirements. The proposed method was successfully applied for the determination of VRC in bulk and tablets with acceptable accuracy and precisions; the label claim percentages were 99.65 ± 0.32%. The results demonstrated that the method would have a great value when applied in quality control and stability studies for VRC. PMID:21672253

  11. Living matter: the "lunar eclipse" phenomena.

    PubMed

    Korpan, Nikolai N

    2010-01-01

    The present investigations describe a unique phenomenon, namely the phenomenon of the "lunar eclipse", which has been observed and discovered by the author in living substance during the freeze-thawing processes in vivo using temperatures of various intensities and its cryosurgical response in animal experiment. Similar phenomena author has observed in nature, namely the total lunar eclipse and total solar eclipse. In this experimental study 76 animals (mongrel dogs) were investigated. A disc cryogenic probe was placed on the pancreas after the laparotomy. For cryosurgical exposure a temperature range of -40 degrees C, -80 degrees C, -120 degrees C and -180 degrees C was selected in contact with pancreas parenchyma. The freeze-thaw cycle was monitored by intraoperative ultrasound before, during and after cryosurgery. Each cryolesion was observed for one hour after thawing intraoperatively. Immediately after freezing, during the thawing process, the snow-white pancreas parenchyma, frozen hard to an ice block and resembling a full moon with a sharp demarcation line, gradually assumed a ruby-red shade and a hemispherical shape as it grew in size depend on reconstruction vascular circulation from the periphery to the center. This snow-white cryogenic lesion dissolved in the same manner in all animal tissues. The "lunar eclipse" phenomenon contributes to a fundamental understanding of the mechanisms of biological tissue damage during low temperature exposure in cryoscience and cryomedicine. Properties of the pancreas parenchyma response during the phenomenon of the "lunar eclipse" provide important insights into the mechanisms of damage and the formation of cryogenic lesion immediately after thawing in cryosurgery. Vascular changes and circulatory stagnation are commonly considered to be the main mechanism of biological tissue injury during low temperature exposure. The phenomenon of the "lunar eclipse" suggests that cryosurgery is the first surgical technique to use

  12. IUE observations of the atmospheric eclipsing binary system Zeta Aurigae

    NASA Technical Reports Server (NTRS)

    Champman, R. D.

    1980-01-01

    IUE observations of the eclipsing binary system Zeta Aurigae made prior to and during the eclipse of the relatively small B8 V star by the cool supergiant star (spectral type K2 II) are reported. Spectral lines produced by the absorption of B star radiation in the atmosphere of the K star during eclipse can be used as a probe of the extended K star atmosphere, due to the negligible cool star continuum in the 1200-3200 A region. Spectra taken prior to eclipse are found to be similar to those of the single B8 V star 64 Ori, with the exception of very strong multi-component absorption lines of Si II, Si IV, C IV and the Mg resonance doublet with strong P Cygni profiles, indicating a double shell. Absorption lines including those corresponding to Al II, Al III, Cr II, Mn II, Fe II, Ni II and Ca II are observed to increase in strength and number as the eclipse progresses, with high-ionization-potential lines formed far from the K star, possibly in a shock wave, and low-ionization potential lines, formed in cool plasma, probably a cool wind, nearer to the K star. Finally, an emission-line spectra with lines corresponding to those previously observed in absorption is noted at the time the B-star continuum had disappeared.

  13. Resource Letter OSE-1: Observing Solar Eclipses

    NASA Astrophysics Data System (ADS)

    Pasachoff, Jay M.; Fraknoi, Andrew

    2017-07-01

    This Resource Letter provides a guide to the available literature, listing selected books, articles, and online resources about scientific, cultural, and practical issues related to observing solar eclipses. It is timely, given that a total solar eclipse will cross the continental United States on August 21, 2017. The next total solar eclipse path crossing the U.S. and Canada will be on April 8, 2024. In 2023, the path of annularity of an annular eclipse will cross Mexico, the United States, and Canada, with partial phases visible throughout those countries.

  14. March 7, 1970 solar eclipse investigation

    NASA Technical Reports Server (NTRS)

    Accardo, C. A.

    1972-01-01

    Studies from rockets directed toward establishing the solar X-ray fluxes during the 7 March 1970 total eclipse over the North American continent are reported. A map of the eclipse path is presented. The measured absorption profiles for the residual X-rays are useful in establishing their contribution to the D and E region ionization during the eclipse. The studies were performed with two Nike-Apache payloads launched over Wallops Island, Virginia. In addition to three X-ray detectors in the 1 to 8A, 8 to 20A and 44 to 60A bands, there was included in the payloads two additional experiments. These were an electric field experiment and an epithermal photoelectron experiment. The X-ray instrumentation, payload description, flight circumstances and finally, the X-ray results obtained are described. The various computer codes employed for the purpose of reducing the telemetered data as well as the eclipse codes are included.

  15. Eclipsing Binaries with Possible Tertiary Components

    NASA Astrophysics Data System (ADS)

    Snyder, LeRoy F.

    2013-05-01

    Many eclipsing binary star systems (EBS) show long-term variations in their orbital periods which are evident in their O-C (observed minus calculated period) diagrams. This research carried out an analysis of 324 eclipsing binary systems taken from the systems analyzed in the Bob Nelson's O-C Files database. Of these 18 systems displayed evidence of periodic variations of the arrival times of the eclipses. These rates of period changes are sinusoidal variations. The sinusoidal character of these variations is suggestive of Keplerian motion caused by an orbiting companion. The reason for these changes is unknown, but mass loss, apsidal motion, magnetic activity and the presence of a third body have been proposed. This paper has assumed light time effect as the cause of the sinusoidal variations caused by the gravitational pull of a tertiary companion orbiting around the eclipsing binary systems. An observed minus calculated (O-C) diagram of the 324 systems was plotted using a quadratic ephemeris to determine if the system displayed a sinusoidal trend in theO-C residuals. After analysis of the 18 systems, seven systems, AW UMa, BB PEG, OO Aql, V508 Oph, VW Cep, WCrv and YY ERI met the benchmark of the criteria of a possible orbiting companion. The other 11 systems displayed a sinusoidal variation in the O-C residuals of the primary eclipses but these systems in the Bob Nelson's O-C Files did not contain times of minimum (Tmin) of the secondary eclipses and therefore not conclusive in determining the presents of the effects of a tertiary companion. An analysis of the residuals of the seven systems yields a light-time semi-amplitude, orbital period, eccentricity and mass of the tertiary companion as the amplitude of the variation is proportional to the mass, period and inclination of the 3rd orbiting body. Knowing the low mass of the tertiary body in the seven cases the possibility of five of these tertiary companions being brown dwarfs is discussed.

  16. Nationwide Eclipse Ballooning Project

    NASA Astrophysics Data System (ADS)

    Colman Des Jardins, Angela; Berk Knighton, W.; Larimer, Randal; Mayer-Gawlik, Shane; Fowler, Jennifer; Harmon, Christina; Koehler, Christopher; Guzik, Gregory; Flaten, James; Nolby, Caitlin; Granger, Douglas; Stewart, Michael

    2016-05-01

    The purpose of the Nationwide Eclipse Ballooning Project is to make the most of the 2017 rare eclipse event in four main areas: public engagement, workforce development, partnership development, and science. The Project is focused on two efforts, both student-led: online live video of the eclipse from the edge of space and the study of the atmospheric response to the eclipse. These efforts, however, involving more than 60 teams across the US, are challenging in many ways. Therefore, the Project is leveraging the NASA Space Grant and NOAA atmospheric science communities to make it a success. The first and primary topic of this poster is the NASA Space Grant supported online live video effort. College and high school students on 48 teams from 31 states will conduct high altitude balloon flights from 15-20 locations across the 8/21/2017 total eclipse path, sending live video and images from near space to a national website. Video and images of a total solar eclipse from near space are fascinating and rare. It’s never been done live and certainly not in a network of coverage across a continent. In addition to the live video to the web, these teams are engaged in several other science experiments as secondary payloads. We also briefly highlight the eclipse atmospheric science effort, where about a dozen teams will launch over one hundred radiosondes from across the 2017 path, recording an unprecedented atmospheric data sample. Collected data will include temperature, density, wind, humidity, and ozone measurements.

  17. Glorious Eclipses

    NASA Astrophysics Data System (ADS)

    Brunier, Serge; Luminet, Jean-Pierre

    2000-12-01

    Stargazers who may have missed the last total solar eclipse of the 20th century this past summer have just been given another chance to observe this "once in a lifetime" occurrence. Inside Glorious Eclipses they will find startling images and rich personal accounts that fully capture this event and other recent eclipses. The book will also insure that readers will not miss another eclipse in the next 60 years! Specially designed in a beautiful, large format, the volume portrays eclipses of all kinds--lunar, solar, and those occurring elsewhere in the Solar System and beyond. Brunier and Luminet have gathered together all aspects of eclipses, and carefully selected a host of lavish images. The authors detail the history of eclipses, the celestial mechanics involved, their observation, and scientific interest. Personal accounts of recent eclipses are also included as well as all relevant information about forthcoming eclipses up to 2060. Complete with NASA maps and data, Glorious Eclipses is the ultimate source for all those interested in these remarkable (and rare) celestial events. Serge Brunier is chief editor of the journal Ciel et Espace, a photo-journalist, and the author of many nonfiction books aimed at both specialists and the general public. Jean-Pierre Luminet is an astrophysicist at the Paris-Meudon Observatory and director of research at the Centre pour la Recherche Scientifique. He is the author of many popular astronomy books, including Black Holes (Cambridge University Press, 1992).

  18. Eclipse 2017: Through the eyes of NASA

    NASA Astrophysics Data System (ADS)

    Mayo, Louis; NASA/GSFC Heliophysics Education Consortium

    2016-10-01

    The August 21, 2017 eclipse will be the first time a total solar eclipse has traversed the Continental US since June 8th, 1918. Anticipation y for energy for this eclipse is off the charts. Over 500 million in North America alone will catch the eclipse in either partial or total phase. Parts of South America, Africa, and Europe will see a partial eclipse as well. NASA is planning to take full advantage of this unique celestial event as an education and public engagement opportunity by leveraging its extensive networks of partners, numerous social media platforms, broadcast media, and its significant unique space assets and people to bring the eclipse to America and the world as only NASA can. This talk will outline NASA's education plans in some detail replicating our many Big Events successes including the 2012 Transit of Venus and the MSL/Curiosity landing and show how scientists and the public can get involved.

  19. Eclipse project QF-106 and C-141A takeoff on first tethered flight December 20, 1997

    NASA Technical Reports Server (NTRS)

    1997-01-01

    TOW ROPE TAKEOFF - The Kelly Space & Technology (KST)/USAF Eclipse project's modified QF-106 and a USAF C-141A takeoff for the project's first tethered flight on December 20, 1997. The successful 18-minute-long flight reached an altitude of 10,000 feet. NASA's Dryden Flight Research Center, Edwards, California, hosted the project, providing engineering and facility support as well as the project pilot. In 1997 and 1998, the Dryden Flight Research Center at Edwards, California, supported and hosted a Kelly Space & Technology, Inc. project called Eclipse, which sought to demonstrate the feasibility of a reusable tow-launch vehicle concept. The project goal was to successfully tow, inflight, a modified QF-106 delta-wing aircraft with an Air Force C-141A transport aircraft. This would demonstrate the possibility of towing and launching an actual launch vehicle from behind a tow plane. Dryden was the responsible test organization and had flight safety responsibility for the Eclipse project. Dryden provided engineering, instrumentation, simulation, modification, maintenance, range support, and research pilots for the test program. The Air Force Flight Test Center (AFFTC), Edwards, California, supplied the C-141A transport aircraft and crew and configured the aircraft as needed for the tests. The AFFTC also provided the concept and detail design and analysis as well as hardware for the tow system and QF-106 modifications. Dryden performed the modifications to convert the QF-106 drone into the piloted EXD-01 (Eclipse eXperimental Demonstrator-01) experimental aircraft. Kelly Space & Technology hoped to use the results gleaned from the tow test in developing a series of low-cost, reusable launch vehicles. These tests demonstrated the validity of towing a delta-wing aircraft having high wing loading, validated the tow simulation model, and demonstrated various operational procedures, such as ground processing of in-flight maneuvers and emergency abort scenarios.

  20. Determination of aflatoxins in food samples by automated on-line in-tube solid-phase microextraction coupled with liquid chromatography-mass spectrometry.

    PubMed

    Nonaka, Y; Saito, K; Hanioka, N; Narimatsu, S; Kataoka, H

    2009-05-15

    A simple and sensitive automated method for determination of aflatoxins (B1, B2, G1, and G2) in nuts, cereals, dried fruits, and spices was developed consisting of in-tube solid-phase microextraction (SPME) coupled with liquid chromatography-mass spectrometry (LC-MS). Aflatoxins were separated within 8 min by high-performance liquid chromatography using a Zorbax Eclipse XDB-C8 column with methanol/acetonitrile (60/40, v/v): 5mM ammonium formate (45:55) as the mobile phase. Electrospray ionization conditions in the positive ion mode were optimized for MS detection of aflatoxins. The pseudo-molecular ions [M+H](+) were used to detect aflatoxins in selected ion monitoring (SIM) mode. The optimum in-tube SPME conditions were 25draw/eject cycles of 40 microL of sample using a Supel-Q PLOT capillary column as an extraction device. The extracted aflatoxins were readily desorbed from the capillary by passage of the mobile phase, and no carryover was observed. Using the in-tube SPME LC-MS with SIM method, good linearity of the calibration curve (r>0.9994) was obtained in the concentration range of 0.05-2.0 ng/mL using aflatoxin M1 as an internal standard, and the detection limits (S/N=3) of aflatoxins were 2.1-2.8 pg/mL. The in-tube SPME method showed >23-fold higher sensitivity than the direct injection method (10 microL injection volume). The within-day and between-day precision (relative standard deviations) at the concentration of 1 ng/mL aflatoxin mixture were below 3.3% and 7.7% (n=5), respectively. This method was applied successfully to analysis of food samples without interference peaks. The recoveries of aflatoxins spiked into nuts and cereals were >80%, and the relative standard deviations were <11.2%. Aflatoxins were detected at <10 ng/g in several commercial food samples.

  1. Simultaneous determination of apatinib and its four major metabolites in human plasma using liquid chromatography-tandem mass spectrometry and its application to a pharmacokinetic study.

    PubMed

    Ding, Juefang; Chen, Xiaoyan; Dai, Xiaojian; Zhong, Dafang

    2012-05-01

    Apatinib, also known as YN968D1, is a novel antiangiogenic agent that selectively inhibits vascular endothelial growth factor receptor-2. Currently, apatinib is undergoing phase II/III clinical trials in China for the treatment of solid tumors. Apatinib is extensively metabolized in humans, and its major metabolites in circulation include cis-3-hydroxy-apatinib (M1-1), trans-3-hydroxy-apatinib (M1-2), apatinib-25-N-oxide (M1-6), and cis-3-hydroxy-apatinib-O-glucuronide (M9-2). To investigate the pharmacokinetics of apatinib and its four major metabolites in patients with advanced colorectal cancer, a sensitive and selective liquid chromatography-tandem mass spectrometry method was developed and validated for the simultaneous determination of apatinib, M1-1, M1-2, M1-6, and M9-2 in human plasma. After a simple protein precipitation using acetonitrile as the precipitation solvent, all the analytes and the internal standard vatalanib were separated on a Zorbax Eclipse XDB C(18) column (50 mm × 4.6 mm, 1.8 μm, Agilent) using acetonitrile: 5 mmol/L ammonium acetate with 0.1% formic acid as the mobile phase with gradient elution. A chromatographic total run time of 9 min was achieved. Mass spectrometry detection was conducted through electrospray ionization in positive ion multiple reaction monitoring modes. The method was linear over the concentration range of 3.00-2000 ng/mL for each analyte. The lower limit of quantification for each analyte was 3.00 ng/mL. The intra-assay precision for all the analytes was less than 11.3%, the inter-assay precision was less than 13.8%, and the accuracy was between -5.8% and 3.3%. The validated method was successfully applied to a clinical pharmacokinetic study following oral administration of 500 mg apatinib mesylate in patients with advanced colorectal cancer. Copyright © 2012 Elsevier B.V. All rights reserved.

  2. Practicing for 2023 and 2024: What the AAS Solar Eclipse Task Force Learned from the "Great American Eclipse" of 2017

    NASA Astrophysics Data System (ADS)

    Fienberg, R. T.; Speck, A. K.; Habbal, S. R.

    2017-12-01

    task force's activities, take stock of what went right and what went wrong, and consider how to do an even better job preparing the nation for the next two "Great American" solar eclipses: the annular eclipse of October 14, 2023, and the total eclipse of April 8, 2024.

  3. The earliest known solar eclipse record redated

    NASA Astrophysics Data System (ADS)

    de Jong, T.; van Soldt, W. H.

    1989-03-01

    An astronomical event recorded on a clay tablet found in 1948 among the ruins of the acient city of Ugarit, in what is now Syria, was identified 20 years ago as a description of a total solar eclipse that occurred on May 3, 1375 B.C. A new historical dating of the tablet, and mention in the text of the visibility of the planet Mars during the eclipse as well as the month it which it occurred, are used here to show that the recorded eclipse in fact occurred on March 5, 1223 B.C. This new date implies that the secular deceleration of the earth's rotation has changed very little during the past 3000 years.

  4. Eclipsing Binaries in Open Clusters

    NASA Astrophysics Data System (ADS)

    Southworth, John; Clausen, Jens Viggo

    2006-08-01

    The study of detached eclipsing binaries in open clusters can provide stringent tests of theoretical stellar evolutionary models, which must simultaneously fit the masses, radii, and luminosities of the eclipsing stars and the radiative properties of every other star in the cluster. We review recent progress in such studies and discuss two unusually interesting objects currently under analysis. GV Carinae is an A0 m + A8 m binary in the Southern open cluster NGC 3532; its eclipse depths have changed by 0.1 mag between 1990 and 2001, suggesting that its orbit is being perturbed by a relatively close third body. DW Carinae is a high-mass unevolved B1 V + B1 V binary in the very young open cluster Collinder 228, and displays double-peaked emission in the centre of the Hα line which is characteristic of Be stars. We conclude by pointing out that the great promise of eclipsing binaries in open clusters can only be satisfied when both the binaries and their parent clusters are well-observed, a situation which is less common than we would like.

  5. Characterization of constituents in Stellera chamaejasme L. by rapid-resolution liquid chromatography-diode array detection and electrospray ionization time-of-flight mass spectrometry.

    PubMed

    Zhao, Liang; Lou, Zi-Yang; Zhu, Zhen-Yu; Zhang, Guo-Qing; Chai, Yi-Feng

    2008-01-01

    A reliable and rapid method based on rapid-resolution liquid chromatography-diode array detection (RRLC-DAD) and electrospray ionization time-of-flight mass spectrometry (ESI-TOF/MS) has been developed for the isolation and characterization of multiple constituents in the root of Stellera chamaejasme L., which was extracted by sonication with methanol in an optimized procedure. Separation of the multiple constituents was achieved on an Agilent Zorbax XDB-C18 (50x3.0 mm i.d.; 1.8 microm) column using a gradient elution at a flow rate of 0.4 mL/min. The detection wavelength was 210 nm. Mass spectra were acquired in both positive and negative modes. A formula database of the known chemical constituents in the root of Stellera chamaejasme L. was established by an Agilent software. Twenty-two obvious peaks appeared in the total ion chromatogram and nine of them were characterized by TOF/MS. The RRLC-DAD and ESI-TOF/MS method with ultrasonic extraction would be useful for rapid and effective characterization of chemical constituents in the root of Stellera chamaejasme L. Copyright (c) 2007 John Wiley & Sons, Ltd.

  6. Evaluating the Eclipse: How good was it?

    NASA Astrophysics Data System (ADS)

    Noel-Storr, Jacob; InsightSTEM Evaluation Team

    2018-01-01

    We present findings from the evaluation program carried out of education, public outreach, and communication activities around the "Great American Eclipse" of August 21, 2017. We include findings drawn from the experiences of 30 participants in planning activities prior to the eclipse and 31 recipients of mini-grants for eclipse activities supported by the American Astronomical Society through a grant from the National Science Foundation. We synthesize evaluations gathered by these and other volunteering organizations to provide a multi-site picture of experiences and learning outcomes at eclipse-related events - both in the path of totality and in partial eclipse settings. We make use of qualitative and quantitative responses representing over 30,000 individuals who observed (or tried to observe) the eclipse. We will share findings from across the range of programs included in our evaluation network along with specific highlights. We emphasize a reflection on the motivation and activity behind the 2017 eclipse, and how to leverage the lessons learned for future events on this scale (such as the eclipse of April 8, 2024) along with messages relevant to other events connected with astronomical phenomena, or in multi-site settings.This work was supported in part by the National Science Foundation under Grant No. 1564535 awarded to the American Astronomical Society. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author and do not necessarily reflect the views of the National Science Foundation or the American Astronomical Society.

  7. Analysis of penumbral eclipse data

    NASA Technical Reports Server (NTRS)

    Garrett, H. B.

    1977-01-01

    Two days of data from the ATS-6 1976 eclipse season were analyzed to determine the effects of varying photoelectron flux on spacecraft potential. Particular emphasis was placed on the variation in potential as the satellite entered the earth's penumbra. Measurements from the AE-C satellite of the solar UV radiation were used to construct a model of atmospheric attenuation. This model was found to be consistent with direct measurements of the variations in photoelectron flux as Injun 5 passed into eclipse. Applying the model to the ATS-6 data gave the time dependency of the solar illumination/photoelectron flux as the satellite was eclipsed. This relationship, when combined with the ATS-6 measurements of satellite potential, revealed a nearly linear relation between the solar illumination/photoelectron flux and the logarithm of the satellite potential.

  8. GSC 4232.2850, a new eclipsing binary with elliptical orbit

    NASA Astrophysics Data System (ADS)

    Goranskij, V.; Shugarov, S.; Kroll, P.; Golovin, A.

    2005-04-01

    GSC 4232.2830 (20h 01m 28s.407, +61? 10' 17".18, 2000.0, v=12m.1) was suspected to be an eclipsing binary by VPG in the routine overview of photographical plates taken with 40-cm astrograph of SAI Crimean station. To define orbital elements of the binary, we searched for observations in Sonneberg Observatory plate collection, NSVS database (Wozniak et al., 2004), and carried out visual monitoring with a small telescope equipped with an electronic image tube, an analogue of a night vision device. Later, when we had found a preliminary solution, we carried out accurate CCD photometry to improve the orbital elements. We should note, that the depths of eclipses in the NSVS database do not exceed 0m.2, what contradicts to other observations. We suppose that NSVS measurements concern to integral light of two stars, a variable star, and a nearby brighter star, GSC 4232.2395, due to low resolution of this survey, 72". Using all the available observations we found the single orbital solution with an elliptical orbit and the period of 11,6 day. The center of the secondary minimum occurs at the orbital phase 0.69835 or 8.1 day after the primary minimum. The improved ephemeris derived using accurate CCD observations is following: HJD Min I = 2453278,3185(2) + 11.628188 (5) x E. O-C analysis does not show orbital period variations during the time interval of observations, or any evidence of apsidal motion. The observations show that both eclipses have about equal depth 0m.60, but essentially different duration, 0p.028 (7 h.8) for Min I, and 0 p.0175 (4 h.9) for Min II. The eclipses are partial. CCD photometry gives mean colors U-B = -0 m.06, B-V = 0 m.57, and V-R = 0 m.50 without notable color variations in the eclipse phases. Old Sonneberg photographic observations indicate that the eclipses were shallower in the middle of the past century than in the present time! Such contradictions may suggest that the depth of eclipses varied, as in the well-known system SSLac

  9. Parallel Eclipse Project Checkout

    NASA Technical Reports Server (NTRS)

    Crockett, Thomas M.; Joswig, Joseph C.; Shams, Khawaja S.; Powell, Mark W.; Bachmann, Andrew G.

    2011-01-01

    Parallel Eclipse Project Checkout (PEPC) is a program written to leverage parallelism and to automate the checkout process of plug-ins created in Eclipse RCP (Rich Client Platform). Eclipse plug-ins can be aggregated in a feature project. This innovation digests a feature description (xml file) and automatically checks out all of the plug-ins listed in the feature. This resolves the issue of manually checking out each plug-in required to work on the project. To minimize the amount of time necessary to checkout the plug-ins, this program makes the plug-in checkouts parallel. After parsing the feature, a request to checkout for each plug-in in the feature has been inserted. These requests are handled by a thread pool with a configurable number of threads. By checking out the plug-ins in parallel, the checkout process is streamlined before getting started on the project. For instance, projects that took 30 minutes to checkout now take less than 5 minutes. The effect is especially clear on a Mac, which has a network monitor displaying the bandwidth use. When running the client from a developer s home, the checkout process now saturates the bandwidth in order to get all the plug-ins checked out as fast as possible. For comparison, a checkout process that ranged from 8-200 Kbps from a developer s home is now able to saturate a pipe of 1.3 Mbps, resulting in significantly faster checkouts. Eclipse IDE (integrated development environment) tries to build a project as soon as it is downloaded. As part of another optimization, this innovation programmatically tells Eclipse to stop building while checkouts are happening, which dramatically reduces lock contention and enables plug-ins to continue downloading until all of them finish. Furthermore, the software re-enables automatic building, and forces Eclipse to do a clean build once it finishes checking out all of the plug-ins. This software is fully generic and does not contain any NASA-specific code. It can be applied to any

  10. Safety assessment of continuous glass filaments used in eclipse.

    PubMed

    Swauger, J E; Foy, J W

    2000-11-01

    Eclipse is a cigarette that produces smoke by primarily heating, rather than burning, tobacco. The Eclipse heat source assembly employs a continuous filament glass mat jacket to insulate the heat source. The glass mat insulator is composed of continuous glass filaments and a binder. The purpose of this article is to address the potential toxicological significance of the continuous glass filaments under the conditions of intended use. Transfer data and the unique physical characteristics of the filaments demonstrate that significant exposure of the smoker will not occur. The available environmental survey data clearly demonstrate that Eclipse smokers are extremely unlikely to be exposed to continuous glass filaments at a level that represents a biologically significant increase over background exposure to glass fibers. The chemical composition of the continuous glass filaments used in Eclipse is generally similar to C-glass fiber compositions such as MMVF 11 that have failed to produce either tumors or fibrosis in chronic inhalation studies conducted in rats. In vitro dissolution data demonstrate that the continuous glass filaments used in Eclipse are more soluble than biologically active fibers such as rock wool (MMVF 21) or asbestos. However, the continuous glass filaments used in Eclipse were not as soluble in simulated extracellular lung fluid as representative C-glass fibers (MMVF 10 and MMVF 11). In brief, exposure of Eclipse smokers to continuous glass filaments is extremely unlikely to occur at a level that may be construed to be of biological significance.

  11. Spectral irradiance curve calculations for any type of solar eclipse

    NASA Technical Reports Server (NTRS)

    Deepak, A.; Merrill, J. E.

    1974-01-01

    A simple procedure is described for calculating the eclipse function (EF), alpha, and hence the spectral irradiance curve (SIC), (1-alpha), for any type of solar eclipse: namely, the occultation (partial/total) eclipse and the transit (partial/annular) eclipse. The SIC (or the EF) gives the variation of the amount (or the loss) of solar radiation of a given wavelength reaching a distant observer for various positions of the moon across the sun. The scheme is based on the theory of light curves of eclipsing binaries, the results of which are tabulated in Merrill's Tables, and is valid for all wavelengths for which the solar limb-darkening obeys the cosine law: J = sub c (1 - X + X cost gamma). As an example of computing the SIC for an occultation eclipse which may be total, the calculations for the March 7, 1970, eclipse are described in detail.

  12. Solar Eclipse Computer API: Planning Ahead for August 2017

    NASA Astrophysics Data System (ADS)

    Bartlett, Jennifer L.; Chizek Frouard, Malynda; Lesniak, Michael V.; Bell, Steve

    2016-01-01

    2024 April 8 Solar Eclipse Resource page (http://aa.usno.navy.mil/data/docs/Eclipse2024.php) is also available.

  13. Infrasonic Effect of Solar Eclipses

    NASA Astrophysics Data System (ADS)

    Pushin, V. F.; Chernogor, L. F.

    2013-06-01

    The relevance of this study is due to the need to understand, physical effects associated with rare phenomenon, solar eclipse. Until recently, the features of internal gravity wave generation, have been studied in the 10 -100 min period range, while in this, study an attempt is made to confirm the fact of generation, and estimate the general parameters of infrasound oscillations, associated with solar eclipses in the 1-10 min period range. The observations were made with the HF Doppler radar at vertical, incidence. The data were subjected to spectral analysis and, band-pass filtering. The solar eclipses that had occurred over, Kharkiv city (Ukraine) within 1999-2011 are determined to be, associated with Doppler shift of frequency oscillations in the, infrasound frequency band ( 5-8 min period range) and with, amplitude of 20 -100 mHz. The corresponding amplitude, of electron density oscillations was approximately equal to, 0.1- 0.5 %.

  14. Fraction of free-base nicotine in fresh smoke particulate matter from the Eclipse "cigarette" by 1H NMR spectroscopy.

    PubMed

    Pankow, James F; Barsanti, Kelley C; Peyton, David H

    2003-01-01

    Solution 1H NMR (proton-NMR) spectroscopy was used to measure the distribution of nicotine between its free-base and protonated forms at 20 degrees C in (a) water; (b) glycerin/water mixtures; and (c) puff-averaged "smoke" particulate matter (PM) produced by the Eclipse cigarette, a so-called "harm reduction" cigarette manufactured by R. J. Reynolds (RJR) Tobacco Co. Smoke PM from the Eclipse contains glycerin, water, nicotine, and numerous other components. Smoke PM from the Eclipse yielded a signal for the three N-methyl protons on nicotine at a chemical shift of delta (ppm) = 2.79 relative to a trimethylsilane standard. With alpha fb = fraction of the total liquid nicotine in free-base form, and alpha a = fraction in the acidic, monoprotonated NicH+ form, then alpha a + alpha fb approximately 1. (The diprotonated form of nicotine was assumed negligible.) When the three types of solutions were adjusted so that alpha a approximately 1, the N-methyl protons yielded delta a = 2.82 (Eclipse smoke PM); 2.79 (35% water/65% glycerin); and 2.74 (water). When the solutions were adjusted so that alpha fb approximately 1, the N-methyl protons yielded delta fb = 2.16 (Eclipse smoke PM); 2.13 (35% water/65% glycerin); and 2.10 (water). In all of the solutions, the rate of proton exchange between NicH+ and Nic was fast relative to the 1H-NMR chemical shift difference in hertz. Each solution containing both NicH+ and Nic thus yielded a single N-methyl peak at a delta given by delta = alpha a delta a + alpha fb delta fb so that delta varied linearly between delta a and delta fb. Since alpha fb = (delta a-delta)/(delta a-delta fb), then delta = 2.79 for the unadjusted Eclipse smoke PM indicates alpha fb approximately 0.04. The effective pH of the Eclipse smoke PM at 20 degrees C may then be calculated as pHeff = 8.06 + log[alpha fb/(1-alpha fb)] = 6.69, where 8.06 is the pKa of NicH+ in water at 20 degrees C. The measurements obtained for the puff-averaged Eclipse smoke PM

  15. Eclipse project QF-106 and C-141A climbs out under tow on first tethered flight December 20, 1997

    NASA Technical Reports Server (NTRS)

    1997-01-01

    TOW LAUNCH DEMONSTRATION - The Kelly Space & Technology (KST)/USAF/NASA Eclipse project's modified QF-106 climbs out under tow by a USAF C-141A on the project's first tethered flight on December 20, 1997. The successful 18-minute-long flight reached an altitude of 10,000 feet. NASA's Dryden Flight Research Center, Edwards, California, hosted the project, providing engineering and facility support as well as the project pilot. In 1997 and 1998, the Dryden Flight Research Center at Edwards, California, supported and hosted a Kelly Space & Technology, Inc. project called Eclipse, which sought to demonstrate the feasibility of a reusable tow-launch vehicle concept. The project goal was to successfully tow, inflight, a modified QF-106 delta-wing aircraft with an Air Force C-141A transport aircraft. This would demonstrate the possibility of towing and launching an actual launch vehicle from behind a tow plane. Dryden was the responsible test organization and had flight safety responsibility for the Eclipse project. Dryden provided engineering, instrumentation, simulation, modification, maintenance, range support, and research pilots for the test program. The Air Force Flight Test Center (AFFTC), Edwards, California, supplied the C-141A transport aircraft and crew and configured the aircraft as needed for the tests. The AFFTC also provided the concept and detail design and analysis as well as hardware for the tow system and QF-106 modifications. Dryden performed the modifications to convert the QF-106 drone into the piloted EXD-01 (Eclipse eXperimental Demonstrator-01) experimental aircraft. Kelly Space & Technology hoped to use the results gleaned from the tow test in developing a series of low-cost, reusable launch vehicles. These tests demonstrated the validity of towing a delta-wing aircraft having high wing loading, validated the tow simulation model, and demonstrated various operational procedures, such as ground processing of in-flight maneuvers and emergency abort

  16. On-line Eclipse Resources from the U.S. Naval Observatory: Planning Ahead for April 2024

    NASA Astrophysics Data System (ADS)

    Fredericks, Amy C.; Bartlett, J. L.; Bell, S.; Stapleton, J. C.

    2014-01-01

    On 8 April 2024, “…night from mid-day…” (Archilochus, 648 BCE) will appear to fortunate observers along a narrow band, approximately 115 mi (185 km) wide, that crosses fifteen states from Texas to Maine. In response to growing interest in the two total solar eclipses that will sweep the continental United States in the next 11 years, the U.S. Naval Observatory has developed an on-line resource center with direct links to 2024-specific services: the 2024 April 8 Total Solar Eclipse page (http://aa.usno.navy.mil/data/docs/Eclipse2024.php). The Solar Eclipse Computer (http://aa.usno.navy.mil/data/docs/SolarEclipses.php) calculates tables of local circumstances for events visible throughout the world. A similar service is available for lunar eclipses, Lunar Eclipse Computer (http://aa.usno.navy.mil/data/docs/LunarEclipse.php). The USNO Eclipse Portal (http://astro.ukho.gov.uk/eclbin/query_usno.cgi) provides diagrams and animations showing the global circumstances for events visible throughout the world and local circumstances for events visible at selected locations. The Web site, which includes both solar and lunar eclipses, is a joint effort with Her Majesty’s Nautical Almanac Office. The Eclipses of the Sun and Moon page (http://aa.usno.navy.mil/data/docs/UpcomingEclipses.php) links to electronic copies of the visibility maps from The Astronomical Almanac. The Eclipse Reference List (http://aa.usno.navy.mil/faq/docs/eclipse_ref.php) is a representative survey of the available literature for those interested in delving into these phenomena, either technically or historically. As exciting as the 2024 total solar eclipse, another spectacular event will precede it; a total solar eclipse will cross a different swath of the continent on August 21, 2017. The U.S. Naval Observatory has a resource center for that event as well (http://aa.usno.navy.mil/data/docs/Eclipse2017.php) . If your plans for 2024 are not yet made, visit the 2024 April 8 Total Solar Eclipse

  17. The 2017 Total Solar Eclipse: Through the Eyes of NASA

    NASA Astrophysics Data System (ADS)

    Young, C. Alex; Mayo, Louis; Ng, Carolyn; Cline, Troy; Lewis, Elaine; Reed, Shannon; Debebe, Asidesach; Stephenson, Bryan; Odenwald, Sten; Hill, Steele; Wright, Ernest

    2017-01-01

    The August 21, 2017 eclipse will be the first time a total solar eclipse has traversed the Continental US since June 8th, 1918. Anticipation and energy for this eclipse is off the charts! Over 500 million in North America alone will catch the eclipse in either partial or total phase. Parts of South America, Africa, and Europe will see a partial eclipse as well. NASA is planning to take full advantage of this unique celestial event as an education and public engagement opportunity by leveraging its extensive networks of partners, numerous social media platforms, broadcast media, and its significant unique space assets and people to bring the eclipse to America and the world as only NASA can.This talk will outline NASA’s education plans in some detail replicating our many Big Events successes including the 2012 Transit of Venus and the MSL/Curiosity landing and show how scientists and the public can get involved.

  18. Lunar Surface Properties from Diviner Eclipse Observations

    NASA Astrophysics Data System (ADS)

    Hayne, Paul; Paige, David; Greenhagen, Benjamin; Bandfield, Joshua; Siegler, Matthew; Lucey, Paul

    2015-04-01

    presence of blocky ejecta material. Comparisons of the rock abundance derived from the eclipse measurements can be made to those derived from the standard Diviner diurnal data [2] in order to constrain the rock size distribution. At a small nighttime cold spot, we observed brightness temperatures during the eclipse that were more than 10K higher than those observed in surrounding non-cold-spot regions. This seemingly paradoxical result implies that the vertical stratigraphy of the Moon's near-surface regolith may be more complex than has been previously appreciated. We are in the process of evaluating several possible explanations for this phenomenon quantitatively. References: [1] Paige D. A., et al. (2010) Space Sci. Rev. 150, 125-160. [2] Bandfield J. L., et al. (2011) J. Geophys. Res., 116, E12. [3] Ghent R. R., et al. (2014) Geology, 42 (12), 1059-1062. [4] Paige D. A., et al. (2010) Science, 330, 479-482. [5] Hayne P. O., et al. (2015) Icarus, submitted. [6] Greenhagen B. T., et al. (2010) Science, 329, 1507-1509. [7] Glotch T. D., et al. (2010) Science, 329, 1510-1513. [8] Allen C. C., et al. (2012) J. Geophys. Res., 117, E12. [9] Bandfield J. L., et al. (2014) Icarus, 231, 221-231. [10] Hayne P. O., et al. (2011) AGU Fall Meeting Abstracts, p. 1712. [11] Hayne P. O., et al. (2010) Science, 330, 477-479. Acknowledgement: Part of this work was performed at the Jet Propulsion Laboratory, California Institute of Technology, under contract with the National Aeronautics and Space Administration.

  19. Annular and Total Solar Eclipses of 2010

    NASA Technical Reports Server (NTRS)

    Espenak, Fred; Anderson, J.

    2008-01-01

    While most NASA eclipse bulletins cover a single eclipse, this publication presents predictions for two solar eclipses during 2010. This has required a different organization of the material into the following sections. Section 1 -- Eclipse Predictions: The section consists of a general discussion about the eclipse path maps, Besselian elements, shadow contacts, eclipse path tables, local circumstances tables, and the lunar limb profile. Section 2 -- Annular Solar Eclipse of 2010 Ja n 15: The section covers predictions and weather prospects for the annular eclipse. Section 3 -- Total Solar Eclipse of 2010 Jul 11: The se ction covers predictions and weather prospects for the total eclipse. Section 4 -- Observing Eclipses: The section provides information on eye safety, solar filters, eclipse photography, and making contact timings from the path limits. Section 5 -- Eclipse Resources: The final section contains a number of resources including information on the IAU Working Group on Eclipses, the Solar Eclipse Mailing List, the NASA eclipse bulletins on the Internet, Web sites for the two 2010 eclipses, and a summary identifying the algorithms, ephemerides, and paramete rs used in the eclipse predictions.

  20. Observations of the eclipsing binary b Persei

    NASA Astrophysics Data System (ADS)

    Templeton, Matthew R.

    2015-01-01

    Dr. Robert Zavala (USNO-Flagstaff) et al. request V time-series observations of the bright variable star b Persei 7-21 January 2015 UT, in hopes of catching a predicted eclipse on January 15. This is a follow-up to the February 2013 campaign announced in Alert Notice 476, and will be used as a photometric comparison for upcoming interferometric observations with the Navy Precision Optical Interferometer (NPOI) in Arizona. b Per (V=4.598, B-V=0.054) is ideal for photoelectric photometers or DSLR cameras. Telescopic CCD observers may observe by stopping down larger apertures. Comparison and check stars assigned by PI: Comp: SAO 24412, V=4.285, B-V = -0.013; Check: SAO 24512, V=5.19, B-V = -0.05. From the PI: "[W]e wanted to try and involve AAVSO observers in a follow up to our successful detection of the b Persei eclipse of Feb 2013, AAVSO Alert Notice 476 and Special Notice 333. Our goal now is to get good time resolution photometry as the third star passes in front of the close ellipsoidal binary. The potential for multiple eclipses exists. The close binary has a 1.5 day orbital period, and the eclipsing C component requires about 4 days to pass across the close binary pair. The primary eclipse depth is 0.15 magnitude. Photometry to 0.02 or 0.03 mags would be fine to detect this eclipse. Eclipse prediction date (JD 2457033.79 = 2015 01 11 UT, ~+/- 1 day) is based on one orbital period from the 2013 eclipse." More information is available at PI's b Persei eclipse web page: http://inside.warren-wilson.edu/~dcollins/bPersei/. Finder charts with sequence may be created using the AAVSO Variable Star Plotter (https://www.aavso.org/vsp). Observations should be submitted to the AAVSO International Database. See full Alert Notice for more details and information on the targets.

  1. Relativistic apsidal motion in eccentric eclipsing binaries

    NASA Astrophysics Data System (ADS)

    Wolf, M.; Claret, A.; Kotková, L.; Kučáková, H.; Kocián, R.; Brát, L.; Svoboda, P.; Šmelcer, L.

    2010-01-01

    Context. The study of apsidal motion in detached eclipsing binary systems is known to be an important source of information about stellar internal structure as well as the possibility of verifying of General Relativity outside the Solar System. Aims: As part of the long-term Ondřejov and Ostrava observational projects, we aim to measure precise times of minima for eccentric eclipsing binaries, needed for the accurate determination of apsidal motion, providing a suitable test of the effects of General Relativity. Methods: About seventy new times of minimum light recorded with photoelectric or CCD photometers were obtained for ten eccentric-orbit eclipsing binaries with significant relativistic apsidal motion. Their O-C diagrams were analysed using all reliable timings found in the literature, and new or improved elements of apsidal motion were obtained. Results: We confirm very long periods of apsidal motion for all systems. For BF Dra and V1094 Tau, we present the first apsidal-motion solution. The relativistic effects are dominant, representing up to 100% of the total observable apsidal-motion rate in several systems. The theoretical and observed values of the internal structure constant k 2 were compared for systems with lower relativistic contribution. Using the light-time effect solution, we predict a faint third component for V1094 Tau orbiting with a short period of about 8 years. Partly based on photoelectric observations secured at the Hvar Observatory, Faculty of Geodesy, Zagreb, Croatia, in October 2008.

  2. Lunar Eclipse

    NASA Image and Video Library

    2003-11-09

    In this lunar eclipse viewed from Merritt Island, Fla., the full moon takes on a dark red color because it is being lighted slightly by sunlight passing through the Earth's atmosphere. This light has the blue component preferentially scattered out (this is also why the sky appears blue from the surface of the Earth), leaving faint reddish light to illuminate the Moon. Eclipses occur when the Sun, Earth and Moon line up. They are rare because the Moon usually passes above or below the imaginary line connecting Earth and the Sun. The Earth casts a shadow that the Moon can pass through - when it does, it is called a lunar eclipse.

  3. Asiago eclipsing binaries program IV. SZ Camelopardalis, a β Cephei pulsator in a quadruple, eclipsing system

    NASA Astrophysics Data System (ADS)

    Tamajo, E.; Munari, U.; Siviero, A.; Tomasella, L.; Dallaporta, S.

    2012-03-01

    We present a spectroscopic and photometric analysis of the multiple system and early-type eclipsing binary SZ Cam (O9 IV + B0.5 V), which consists of an eclipsing SB2 pair of orbital period P = 2.7 days in a long orbit (~55 yrs) around a non-eclipsing SB1 pair of orbital period P = 2.8 days. We have reconstructed the spectra of the individual components of SZ Cam from the observed composite spectra using the technique of spectral disentangling. We used them together with extensive and accurate BVIC CCD photometry to obtain an orbital solution. Our photometry revealed the presence of a β Cep variable in the SZ Cam hierarchical system, probably located within the non-eclipsing SB1 pair. The pulsation period is (0.33265 ± 0.00005) days and the observed total amplitude in the B band is (0.0105 ± 0.0005) mag. NLTE analysis of the disentangled spectra provided atmospheric parameters for all three components, consistent with those derived from orbital solution. Full Table 3 is only available at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/539/A139

  4. Searching for planets around eclipsing binary stars using timing method: NSVS 14256825

    NASA Astrophysics Data System (ADS)

    Nasiroglu, Ilham; Goździewski, Krzysztof; Słowikowska, Aga; Krzeszowski, Krzysztof; Żejmo, Michal; Zola, Staszek; Er, Huseyin

    2018-04-01

    We present four new mid eclipse times and an updated O-C diagram of the short period eclipsing binary NSVS14256825. The new data follow the (O-C) trend and its model proposed in Nasiroglu et al. (2017). The (O-C) diagram shows quasi-periodic variations that can be explained with the presence of a brown-dwarf in a quasi-circular circumbinary orbit.

  5. An Atlas of O-C Diagrams of Eclipsing Binary Stars

    NASA Astrophysics Data System (ADS)

    Kreiner, Jerzy M.; Kim, Chun-Hwey; Nha, Il-Seong

    The Atlas contains data for 1,138 eclipsing binaries represented by 91,798 minima timings, collected from the usual international and local journals, observatory publications and unpublished minima. Among this source material there is a considerable representation of amateur astronomers. Some timings were found in the card-index catalogue of the Astronomical Observatory of the Jagiellonian University, Cracow. Stars were included in the Atlas provided that they satisfied 3 criteria: (1) at least 20 minima had been times; (2) these minima spanned at least 2,500 cycles; and (3) the 2,500 cycles represented no fewer than 40 years. Some additional stars not strictly satisfying these criteria were also included if useful information was available. For each star, the Atlas contains the (O-C) diagram calculated by the authors and a table of general information containing: binary characteristics; assorted catalogue numbers; the statistics of the collected minima timings; the light elements (light ephemeris); comments and literature references. All of the data and diagrams in the Atlas are also available in electronic form on the Internet at c">http://www.as.ap.krakow.pl/o- c".

  6. Solar eclipse over the South Pacific Ocean

    NASA Image and Video Library

    2017-12-08

    During a total solar eclipse, the MODIS instrument on NASA's Aqua satellite recorded this image of the shadow of the moon over the South Pacific Ocean on March 8, 2016, at 10:05 pm EST. This total solar eclipse was the last one before an August 21, 2017, total solar eclipse that will be visible in much of the United States. Credit: NASA/Goddard/Jeff Schmaltz/MODIS Land Rapid Response Team 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

  7. Eclipses and dust formation by WC9 type Wolf-Rayet stars

    NASA Astrophysics Data System (ADS)

    Williams, P. M.

    2014-12-01

    Visual photometry of 16 WC8-9 dust-making Wolf-Rayet (WR) stars during 2001-2009 was extracted from the All-Sky Automated Survey All Star Catalogue (ASAS-3) to search for eclipses attributable to extinction by dust formed in clumps in our line of sight. Data for a comparable number of dust-free WC6-9 stars were also examined to help characterize the data set. Frequent eclipses were observed from WR 104, and several from WR 106, extending the 1994-2001 studies by Kato et al., but not supporting their phasing the variations in WR 104 with its `pinwheel' rotation period. Only four other stars showed eclipses, WR 50 (one of the dust-free stars), WR 69, WR 95 and WR 117, and there may have been an eclipse by WR 121, which had shown two eclipses in the past. No dust eclipses were shown by the `historic' eclipsers WR 103 and WR 113. The atmospheric eclipses of the latter were observed but the suggestion by David-Uraz et al. that dust may be partly responsible for these is not supported. Despite its frequent eclipses, there is no evidence in the infrared images of WR 104 for dust made in its eclipses, demonstrating that any dust formed in this process is not a significant contributor to its circumstellar dust cloud and suggesting that the same applies to the other stars showing fewer eclipses.

  8. Eclipse Soundscapes Project: Making the August 21, 2017 Total Solar Eclipse Accessible to Everyone

    NASA Astrophysics Data System (ADS)

    Winter, H. D., III

    2017-12-01

    The Eclipse Soundscapes Project delivered a multisensory experience that allowed the blind and visually impaired to engage with the August 21, 2017 total solar eclipse along with their sighted peers in a way that would not have been possible otherwise. The project, from the Smithsonian Astrophysical Observatory and NASA's Heliophysics Education Consortium, includes illustrative audio descriptions of the eclipse in real time, recordings of the changing environmental sounds during the eclipse, and an interactive "rumble map" app that allows users to experience the eclipse through touch and sound. The Eclipse Soundscapes Project is working with organizations such as the National Parks Service (NPS), Science Friday, and Brigham Young University and by WGBH's National Center for Accessible Media (NCAM) to bring the awe and wonder of the total solar eclipse and other astronomical phenomena to a segment of the population that has been excluded from and astronomy and astrophysics for far too long, while engaging all learners in new and exciting ways.

  9. Addressing Students' Misconceptions about Eclipses

    ERIC Educational Resources Information Center

    Slater, Timothy F.; Gelderman, Richard

    2017-01-01

    The upcoming Aug. 21, 2017, total solar eclipse, with its 70-mile wide path of totality stretching across much of North America, provides us with a unique opportunity to teach students about eclipses. One might naturally assume that students have little difficulty understanding the nature of eclipses. After all, the notion that eclipses occur when…

  10. The extraneous eclipses on binary light curves: KIC 5255552, KIC 10091110, and KIC 11495766

    NASA Astrophysics Data System (ADS)

    Zhang, J.; Qian, S. B.; Wang, S. M.; Sun, L. L.; Wu, Y.; Jiang, L. Q.

    2018-03-01

    Aims: We aim to find more eclipsing multiple systems and obtain their parameters, thus increasing our understanding of multiple systems. Methods: The extraneous eclipses on the Kepler binary light curves indicating extraneous bodies were searched. The binary light curves were analyzed using the binary model, and the extraneous eclipses were studied on their periodicity and shape changes. Results: Three binaries with extraneous eclipses on the binary light curves were found and studied based on the Kepler observations. The object KIC 5255552 is an eclipsing triple system with a fast changing inner binary and an outer companion uncovered by three groups of extraneous eclipses of 862.1(±0.1) d period. The KIC 10091110 is suggested to be a double eclipsing binary system with several possible extraordinary coincidences: the two binaries share similar extremely small mass ratios (0.060(13) and 0.0564(18)), similar mean primary densities (0.3264(42) ρ⊙ and 0.3019(28) ρ⊙), and, most notably, the ratio of the two binaries' periods is very close to integer 2 (8.5303353/4.2185174 = 2.022). The KIC 11495766 is a probable triple system with a 120.73 d period binary and (at least) one non-eclipse companion. Furthermore, very close to it in the celestial sphere, there is a blended background stellar binary of 8.3404432 d period. A first list of 25 eclipsing multiple candidates is presented, with the hope that it will be beneficial for study of eclipsing multiples.

  11. Exoplanet Characterization With Spitzer Eclipses

    NASA Astrophysics Data System (ADS)

    Harrington, Joseph

    We will analyze our existing Spitzer eclipse data for 11 exoplanets (GJ 436b, WASP-8b, WASP-29b, WASP-11b, TrES-1, WASP-34b, WASP-43b, HD 209458b, HAT-P-30b, HAT-P-13b, and WASP-12b) along with all other Spitzer eclipse and transit data for these systems (723 hours of total data). In combination with transit results, these measurements reveal the surface fluxes emitted by the planets' atmospheres in the six Spitzer bandpasses (3.6, 4.5, 5.8, 8.0, 16, and 24 1-4m), as well as orbital eccentricity and in a few cases possibly even precession rate. The fluxes, in turn, can constrain atmospheric composition and thermal profiles. We propose here to analyze data for these planets using Monte Carlo-driven, radiative-transfer, model-fitting codes; to conduct aggregate analyses; and to develop and share statistical modeling tools. Secondary eclipses provide us with a unique way to characterize exoplanetary atmospheres. Since other techniques like spectroscopy divide the planetary signal into many channels, they require very high signal-to-noise ratio (S/N) and are only possible for a few planets. Broadband eclipse photometry is thus the only technique that can measure dozens of atmospheres and identify the mechanisms that cause planets at a given irradiation level to behave so differently from one another. Until JWST becomes available, the broad variety of Spitzer data that we already have in hand, along with observations from the Hubble Space Telescope and possibly SOFIA, are our best way to understand the wide diversity of exoplanetary atmospheres. Since 2010, the team has produced six papers from a new, highly modular pipeline that implements optimal methods for analysis of Spitzer photometric time series, and our efficiency is increasing. The sensitivity needed for these measurements is up to 100 times better than Spitzer's design criteria, so careful treatment of systematic error is critically important and first-order approximations rarely work. The new pipeline

  12. Eclipses of the inner satellites of Jupiter observed in 2015

    NASA Astrophysics Data System (ADS)

    Saquet, E.; Emelyanov, N.; Colas, F.; Arlot, J.-E.; Robert, V.; Christophe, B.; Dechambre, O.

    2016-06-01

    Aims: During the 2014-2015 campaign of mutual events, we recorded ground-based photometric observations of eclipses of Amalthea (JV) and, for the first time, Thebe (JXIV) by the Galilean moons. We focused on estimating whether the positioning accuracy of the inner satellites determined with photometry is sufficient for dynamical studies. Methods: We observed two eclipses of Amalthea and one of Thebe with the 1 m telescope at Pic du Midi Observatory using an IR filter and a mask placed over the planetary image to avoid blooming features. A third observation of Amalthea was taken at Saint-Sulpice Observatory with a 60 cm telescope using a methane filter (890 nm) and a deep absorption band to decrease the contrast between the planet and the satellites. After background removal, we computed a differential aperture photometry to obtain the light flux, and followed with an astrometric reduction. Results: We provide astrometric results with an external precision of 53 mas for the eclipse of Thebe, and 20 mas for that of Amalthea. These observation accuracies largely override standard astrometric measurements. The (O - C)s for the eclipse of Thebe are 75 mas on the X-axis and 120 mas on the Y-axis. The (O - C)s for the total eclipses of Amalthea are 95 mas and 22 mas, along the orbit, for two of the three events. Taking into account the ratio of (O - C) to precision of the astrometric results, we show a significant discrepancy with the theory established by Avdyushev and Ban'shikova in 2008, and the JPL JUP 310 ephemeris. Three of the four eclipse observations where recorded at the 1 m telescope of Pic du Midi Observatory (S2P), the other at Saint-Sulpice Observatory.

  13. Modeling Amateur Radio Soundings of the Ionospheric Response to the 2017 Great American Eclipse

    NASA Astrophysics Data System (ADS)

    Frissell, N. A.; Katz, J. D.; Gunning, S. W.; Vega, J. S.; Gerrard, A. J.; Earle, G. D.; Moses, M. L.; West, M. L.; Huba, J. D.; Erickson, P. J.; Miller, E. S.; Gerzoff, R. B.; Liles, W.; Silver, H. W.

    2018-05-01

    On 21 August 2017, a total solar eclipse traversed the continental United States and caused large-scale changes in ionospheric densities. These were detected as changes in medium- and high-frequency radio propagation by the Solar Eclipse QSO Party citizen science experiment organized by the Ham Radio Science Citizen Investigation (hamsci.org). This is the first eclipse-ionospheric study to make use of measurements from a citizen-operated, global-scale HF propagation network and develop tools for comparison to a physics-based model ionosphere. Eclipse effects were observed ±0.3 hr on 1.8 MHz, ±0.75 hr on 3.5 and 7 MHz, and ±1 hr on 14 MHz and are consistent with eclipse-induced ionospheric densities. Observations were simulated using the PHaRLAP raytracing toolkit in conjunction with the eclipsed SAMI3 ionospheric model. Model results suggest 1.8, 3.5, and 7 MHz refracted at h≥125 km altitude with elevation angles θ≥22°, while 14 MHz signals refracted at h < 125 km with elevation angles θ < 10°.

  14. V380 Dra: New short-period totally eclipsing active binary

    NASA Astrophysics Data System (ADS)

    Özdarcan, O.

    2014-02-01

    In this study, first complete and standard BVR light curves and photometric analysis of the eclipsing binary system V380 Dra are presented. Photometric analysis result indicates that the system has components which are cool main sequence stars. In light and color curves, remarkable asymmetry is observed, especially after secondary minimum, which is believed to be a result of chromospheric activity in one or both components. O-C diagram of available small number of eclipse times, together with new eclipse timings in this work, exhibits no significant variation. Preliminary light curve solution shows that the secondary minimum is total eclipse. By using the advantage of total eclipse and mass-luminosity relation, it is found that the system has a possible mass ratio of q = 0.81. First estimation of masses and radii of primary and secondary components are M1 = 0.77 M⊙,M2 = 0.62 M⊙ and R1 = 0.93 R⊙,R2 = 0.77 R⊙, respectively.

  15. Solar Eclipses Observed from Antarctica

    NASA Astrophysics Data System (ADS)

    Pasachoff, Jay M.

    2013-01-01

    Aspects of the solar corona are still best observed during totality of solar eclipses, and other high-resolution observations of coronal active regions can be observed with radio telescopes by differentiation of occultation observations, as we did with the Jansky Very Large Array for the annular solar eclipse of 2012 May 20 in the US. Totality crossing Antarctica included the eclipse of 2003 November 23, and will next occur on 2021 December 4; annularity crossing Antarctica included the eclipse of 2008 February 7, and will next occur on 2014 April 29. Partial phases as high as 87% coverage were visible and were imaged in Antarctica on 2011 November 25, and in addition to partial phases of the total and annular eclipses listed above, partial phases were visible in Antarctica on 2001 July 2011, 2002 December 4, 2004 April 19, 2006 September 22, 2007 September 11, and 2009 January 26, and will be visible on 2015 September 13, 2016 September 1, 2017 February 26, 2018 February 15, and 2020 December 14. On behalf of the Working Group on Solar Eclipses of the IAU, the poster showed the solar eclipses visible from Antarctica and this article shows a subset (see www.eclipses.info for the full set). A variety of investigations of the Sun and of the response of the terrestrial atmosphere and ionosphere to the abrupt solar cutoff can be carried out at the future eclipses, making the Antarctic observations scientifically useful.

  16. Io Eclipse Montage

    NASA Technical Reports Server (NTRS)

    2007-01-01

    New Horizons took this montage of images of Jupiter's volcanic moon Io, glowing in the dark of Jupiter's shadow, as the Pluto-bound spacecraft sped through the Jupiter system on Feb. 27, 2007.

    (A): In this picture from the Long-Range Reconnaissance Imager (LORRI), dark blotches and straight lines are artifacts. The brightest spots (including the volcanoes Pele [P] and East Girru [EG]) are incandescent lava from active volcanoes. The more diffuse glows, and the many faint spots, are from gas in the plumes and atmosphere, glowing due to bombardment by plasma in Jupiter's magnetosphere, in a display similar to the Earth's aurorae. (B): The same image with a latitude/longitude grid, showing that the cluster of faint spots is centered near longitude 0 degrees, the point on Io that faces Jupiter. The image also shows the locations of the plumes seen in sunlit images (indicated by red diamonds), which glow with auroral emission in eclipse. (C): Simulated sunlit view of Io with the same geometry, based on sunlit LORRI images. (D): A combination of the sunlit image (in cyan) and the eclipse image (in red), showing that all point-like glows in the eclipse image arise from dark volcanoes in the eclipse image. (E): This infrared image, at a wavelength of 2.3 microns, obtained by New Horizons Linear Etalon Spectral Imaging Array (LEISA) an hour after the LORRI image, showing thermal emission from active volcanoes. Elongation of the hot spots is an artifact. (F): Combined visible albedo (cyan) and LEISA thermal emission (red) image, showing the sources of the volcanic emission. That most of the faint point-like glows near longitude zero, seen in visible light in images A, B, and D, do not appear in the infrared view of volcanic heat radiation, is one reason scientists believe that these glows are due to auroral emission, not heat radiation.

    This image appears in the Oct. 12, 2007, issue of Science magazine, in a paper by John Spencer, et al.

  17. Fall 2011 Eclipse Season Begins

    NASA Image and Video Library

    2017-12-08

    The Fall 2011 eclipse season started on September 11. Here is an AIA 171 image from 0657 UT with the first eclipse! SDO has eclipse seasons twice a year near each equinox. For three weeks near midnight Las Cruces time (about 0700 UT) our orbit has the Earth pass between SDO and the Sun. These eclipses can last up to 72 minutes in the middle of an eclipse season. The current eclipse season started on September 11 and lasts until October 4. To read more about SDO go to: sdo.gsfc.nasa.gov/ Credit: NASA/GSFC/SDO 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

  18. Modeling the Effects of Asynchronous Rotation on Secondary Eclipse Timings in HW VIr Binaries

    NASA Astrophysics Data System (ADS)

    Clancy, Padraig

    2018-01-01

    HW Vir binaries are post common envelope binaries consisting of a hot subdwarf and red dwarf, with light curves dominated by primary eclipses, a strong reflection effect, and secondary eclipses. They have orbital periods ranging from a few hours to half a day and are generally thought to be tidally locked; most studies assume both synchronous rotation and zero eccentricity when modeling HW Vir light curves and radial velocities. Their stable eclipse timings are frequently used in O-C studies to look for the presence of circumbinary objects, measure evolutionary changes in the orbital period, and even constrain the component masses through Roemer delay measurements of the secondary eclipse. While most systems are probably tidally locked or close to it, even slightly asynchronous rotation could theoretically shift the orbital phase of the reflection effect. Here we investigate how asynchronous rotation might affect measurements of secondary eclipse timings by generating thousands of synthetic light curves with a range of reflection effect phases, fitting eclipse timings, and creating O-C diagrams.

  19. 2017 Total Solar Eclipse

    NASA Image and Video Library

    2017-08-21

    NASA employees and contractors use protective glasses to view a partial solar eclipse from NASA Headquarters Monday, Aug. 21, 2017 in Washington. A total solar eclipse swept across a narrow portion of the contiguous United States from Lincoln Beach, Oregon to Charleston, South Carolina. A partial solar eclipse was visible across the entire North American continent along with parts of South America, Africa, and Europe. Photo Credit: (NASA/Gwen Pitman)

  20. 2017 Total Solar Eclipse

    NASA Image and Video Library

    2017-08-22

    NASA employees and contractors use protective glasses to view a partial solar eclipse from NASA Headquarters Tuesday, Aug. 22, 2017 in Washington. A total solar eclipse swept across a narrow portion of the contiguous United States from Lincoln Beach, Oregon to Charleston, South Carolina. A partial solar eclipse was visible across the entire North American continent along with parts of South America, Africa, and Europe. Photo Credit: (NASA/Gwen Pitman)

  1. 2017 Total Solar Eclipse

    NASA Image and Video Library

    2017-08-21

    Robert Lightfoot, acting NASA administrator and Thomas Zurbuchen NASA AA for the science mission directorate view a partial eclipse solar eclipse Monday, August 21, 2017, from onboard a NASA Armstrong Flight Research Center’s Gulfstream III 35,000 feet above the Oregon Coast. A total solar eclipse swept across a narrow portion of the contiguous United States from Lincoln Beach, Oregon to Charleston, South Carolina. Photo Credit: (NASA/Carla Thomas)

  2. 2017 Total Solar Eclipse

    NASA Image and Video Library

    2017-08-21

    This composite image of nine pictures shows the progression of a partial solar eclipse near Banner, Wyoming on Monday, Aug. 21, 2017. A total solar eclipse swept across a narrow portion of the contiguous United States from Lincoln Beach, Oregon to Charleston, South Carolina. A partial solar eclipse was visible across the entire North American continent along with parts of South America, Africa, and Europe. Photo Credit: (NASA/Joel Kowsky)

  3. In the Shadow of the Moon, What Type of Solar Eclipse Will We See?

    ERIC Educational Resources Information Center

    Brown, Todd; Brown, Katrina

    2017-01-01

    Solar eclipses occur several times a year, but most people will be lucky if they see one total solar eclipse in their lifetime. There are two upcoming total solar eclipses that can be seen from different parts of the United States (August 21, 2017 and April 8, 2024), and they provide teachers with an amazing opportunity to engage students with a…

  4. Massive eclipsing binary candidates

    NASA Technical Reports Server (NTRS)

    Garrison, R. F.; Schild, R. E.; Hiltner, W. A.

    1983-01-01

    New UBV data are provided for 63 southern OB stars which are either identified in the survey by Garrison, Hiltner, and Schild as having double lines or are known from Wood et al. to be eclipsing binaries. Twenty of the stars are known eclipsing variables. Four stars, not previously known as eclipsing, have both spectroscopic evidence of duplicity and significant photometric variations. Several additional stars have a marginally significant spread in V magnitude.

  5. 2017 Total Solar Eclipse

    NASA Image and Video Library

    2017-08-21

    The Moon is seen passing in front of the Sun during a solar eclipse from Ross Lake, Northern Cascades National Park, Washington on Monday, Aug. 21, 2017. A total solar eclipse swept across a narrow portion of the contiguous United States from Lincoln Beach, Oregon to Charleston, South Carolina. A partial solar eclipse was visible across the entire North American continent along with parts of South America, Africa, and Europe. Photo Credit: (NASA/Bill Ingalls)

  6. 2017 Total Solar Eclipse

    NASA Image and Video Library

    2017-08-21

    The Sun is seen as it rises behind Jack Mountain head of the solar eclipse, Monday, Aug. 21, 2017, Ross Lake, Northern Cascades National Park, Washington. A total solar eclipse will sweep across a narrow portion of the contiguous United States from Lincoln Beach, Oregon to Charleston, South Carolina. A partial solar eclipse was visible across the entire North American continent along with parts of South America, Africa, and Europe. Photo Credit: (NASA/Bill Ingalls)

  7. 2017 Total Solar Eclipse

    NASA Image and Video Library

    2017-08-21

    This composite image shows the progression of a partial solar eclipse over Ross Lake, in Northern Cascades National Park, Washington on Monday, Aug. 21, 2017. A total solar eclipse swept across a narrow portion of the contiguous United States from Lincoln Beach, Oregon to Charleston, South Carolina. A partial solar eclipse was visible across the entire North American continent along with parts of South America, Africa, and Europe. Photo Credit: (NASA/Bill Ingalls)

  8. Line Identifications in the Far Ultraviolet Spectrum of the Eclipsing Binary System 31 Cygni

    NASA Astrophysics Data System (ADS)

    Hagen Bauer, Wendy; Bennett, P. D.

    2011-05-01

    The eclipsing binary system 31 Cygni (K4 Ib + B3 V) was observed at several phases with the Far Ultraviolet Spectrosocopic Explorer (FUSE) satellite. During total eclipse, a rich emission spectrum was observed, produced by scattering of hot star photons in the extended wind of the K supergiant. The system was observed during deep chromospheric eclipse, and 2.5 months after total eclipse ended. We present an atlas of line identifications in these spectra. During total eclipse, emission features from C II , C III, N I, N II, N III, O I, Si II, P II, P III, S II, S III, Ar I, Cr III, Fe II, Fe III, and Ni II were detected. The strongest emission features arise from N II. These lines appear strongly in absorption during chromospheric eclipse, and even 2.5 months after total eclipse, the absorption bottoms out on the underlying emission seen during total eclipse. The second strongest features in the emission spectrum arise from Fe III. Any chromospheric Fe III absorption is buried within strong chromospheric absorption from other species, mainly Fe II. The emission profiles of most of the doubly-ionized species are red-shifted relative to the systemic velocity, with asymmetric profiles with a steeper long-wavelength edge. Emission profiles from singly-ionized species tend to be more symmetric and centered near the systemic velocity. In deep chromospheric eclipse, absorption features are seen from neutral and singly-ionized species, arising from lower levels up to 3 eV. Many strong chromospheric features are doubled in the observation obtained during egress from eclipse. The 31 Cygni spectrum taken 2.5 months after total eclipse ended ws compared to single-star B spectra from the FUSE archives. There was still some additional chromospheric absorption from strong low-excitation Fe II, O I and Ar I.

  9. Eclipse program QF-106 aircraft in flight

    NASA Technical Reports Server (NTRS)

    1997-01-01

    This photo shows one of the QF-106s used in the Eclipse project in flight. In 1997 and 1998, the Dryden Flight Research Center at Edwards, California, supported and hosted a Kelly Space & Technology, Inc. project called Eclipse, which sought to demonstrate the feasibility of a reusable tow-launch vehicle concept. The project goal was to successfully tow, inflight, a modified QF-106 delta-wing aircraft with an Air Force C-141A transport aircraft. This would demonstrate the possibility of towing and launching an actual launch vehicle from behind a tow plane. Dryden was the responsible test organization and had flight safety responsibility for the Eclipse project. Dryden provided engineering, instrumentation, simulation, modification, maintenance, range support, and research pilots for the test program. The Air Force Flight Test Center (AFFTC), Edwards, California, supplied the C-141A transport aircraft and crew and configured the aircraft as needed for the tests. The AFFTC also provided the concept and detail design and analysis as well as hardware for the tow system and QF-106 modifications. Dryden performed the modifications to convert the QF-106 drone into the piloted EXD-01 (Eclipse eXperimental Demonstrator-01) experimental aircraft. Kelly Space & Technology hoped to use the results gleaned from the tow test in developing a series of low-cost, reusable launch vehicles. These tests demonstrated the validity of towing a delta-wing aircraft having high wing loading, validated the tow simulation model, and demonstrated various operational procedures, such as ground processing of in-flight maneuvers and emergency abort scenarios.

  10. KIC 4150611: a rare multi-eclipsing quintuple with a hybrid pulsator

    NASA Astrophysics Data System (ADS)

    Hełminiak, K. G.; Ukita, N.; Kambe, E.; Kozłowski, S. K.; Pawłaszek, R.; Maehara, H.; Baranec, C.; Konacki, M.

    2017-06-01

    Aims: We aim to analyse KIC 4150611 (HD 181469) - an interesting, bright quintuple system that includes a hybrid δ Sct/γ Dor pulsator. Four periods of eclipses - 94.2, 8.65, 1.52 and 1.43 d - have been observed by the Kepler satellite, and three point sources (A, B, and C) are seen in high angular resolution images. Methods: From spectroscopic observations made with the HIDES spectrograph attached to the 1.88-m telescope of the Okayama Astrophysical Observatory (OAO), we have calculated for the first time radial velocities (RVs) of the component B - a pair of G-type stars - and combined them with Kepler photometry in order to obtain absolute physical parameters of this pair. We also managed to directly measure RVs of the pulsator, for the first time. Additionally, we modelled the light curves of the 1.52 and 1.43-day pairs, and measured their eclipse timing variations (ETVs). We also performed relative astrometry and photometry of three sources seen on the images taken with the NIRC2 camera of the Keck II telescope. Finally, we compared our results with theoretical isochrones. Results: The brightest component Aa is the hybrid pulsator, transited every 94.2 days by a pair of K/M-type stars (Ab1+Ab2), which themselves form a 1.52-day eclipsing binary. The components Ba and Bb are late G-type stars, forming another eclipsing pair with a 8.65 day period. Their masses and radii are MBa = 0.894 ± 0.010 M⊙, RBa = 0.802 ± 0.044 R⊙ for the primary, and MBb = 0.888 ± 0.010 M⊙, RBb = 0.856 ± 0.038 R⊙ for the secondary. The remaining period of 1.43 days is possibly related to a faint third star C, which itself is most likely a background object. The system's properties are well-represented by a 35 Myr isochrone, basing on which the masses of the pulsator and the 1.52-day pair are MAa = 1.64(6) M⊙, and MAb,tot = 0.90(13) M⊙, respectively. There are also suggestions of additional bodies in the system.

  11. Eclipses in Australian Aboriginal Astronomy

    NASA Astrophysics Data System (ADS)

    Hamacher, Duane W.; Norris, Ray P.

    2011-07-01

    We explore about fifty different Australian Aboriginal accounts of lunar and solar eclipses to determine how Aboriginal groups understood this phenomenon. We summarize the literature on Aboriginal references to eclipses. We show that many Aboriginal groups viewed eclipses negatively, frequently associating them with bad omens, evil magic, disease, blood and death. In many communities, elders or medicine men claimed to be able to control or avert eclipses by magical means, solidifying their roles as providers and protectors within their communities. We also show that some Aboriginal groups seem to have understood the motions of the Sun-Earth-Moon system, the connection between the lunar phases and tides, and acknowledged that solar eclipses were caused by the Moon blocking the Sun.

  12. Benchmark Transiting Brown Dwarf LHS 6343 C: Spitzer Secondary Eclipse Observations Yield Brightness Temperature and Mid-T Spectral Class

    NASA Astrophysics Data System (ADS)

    Montet, Benjamin T.; Johnson, John Asher; Fortney, Jonathan J.; Desert, Jean-Michel

    2016-05-01

    There are no field brown dwarf analogs with measured masses, radii, and luminosities, precluding our ability to connect the population of transiting brown dwarfs with measurable masses and radii and field brown dwarfs with measurable luminosities and atmospheric properties. LHS 6343 C, a weakly irradiated brown dwarf transiting one member of an M+M binary in the Kepler field, provides the first opportunity to probe the atmosphere of a non-inflated brown dwarf with a measured mass and radius. Here, we analyze four Spitzer observations of secondary eclipses of LHS 6343 C behind LHS 6343 A. Jointly fitting the eclipses with a Gaussian process noise model of the instrumental systematics, we measure eclipse depths of 1.06 ± 0.21 ppt at 3.6 μm and 2.09 ± 0.08 ppt at 4.5 μm, corresponding to brightness temperatures of 1026 ± 57 K and 1249 ± 36 K, respectively. We then apply brown dwarf evolutionary models to infer a bolometric luminosity {log}({L}\\star /{L}⊙ )=-5.16+/- 0.04. Given the known physical properties of the brown dwarf and the two M dwarfs in the LHS 6343 system, these depths are consistent with models of a 1100 K T dwarf at an age of 5 Gyr and empirical observations of field T5-6 dwarfs with temperatures of 1070 ± 130 K. We investigate the possibility that the orbit of LHS 6343 C has been altered by the Kozai-Lidov mechanism and propose additional astrometric or Rossiter-McLaughlin measurements of the system to probe the dynamical history of the system.

  13. Eclipse Megamovie: Solar Discoveries, Education, and Outreach through Crowdsourcing 2017 Eclipse Images

    NASA Astrophysics Data System (ADS)

    Peticolas, L. M.; Hudson, H. S.; Martinez Oliveros, J. C.; Johnson, C.; Zevin, D.; Krista, L. D.; Bender, M.; Mcintosh, S. W.; Konerding, D.; Koh, J.; Pasachoff, J.; Lorimore, B.; Jiang, G.; Storksdieck, M.; Yan, D.; Shore, L.; Fraknoi, A.; Filippenko, A.

    2016-12-01

    Since 2011, a team of solar scientists, eclipse chasers, education and outreach professionals, and film makers have been working to explore the possibility of gathering images from the public during the 2017 eclipse across the United States, to be used for scientific research, education, and enhancing the public's experience of the eclipse. After years of testing the initial ideas, engaging new organizations, and exploring new technologies, our team has developed a blueprint for this project. There are three main goals for this effort: 1. to learn more about the dynamic non-equilibrium processes in the corona and lower atmosphere of the Sun, 2. to educate the public about space physics, 3. provide different levels of engagement opportunities for an interested public, and 4. to understand how these various levels of engagement with a major scientific phenomena allow people to develop deeper personal connections to Science, Technology, Engineering, and Mathematics (STEM). We will meet these goals by training 1000 volunteers to take scientifically valid images and donate the images to this project, while also allowing the general public to share their images as well. During the Aug 21, 2017 eclipse, we will analyze these images in real-time to produce public-generated movies showing the corona of the Sun during totality from thousands of people. These movies will be disseminated in near real-time (on the order of 10s of minutes) to other eclipse programs, news organizations, and to the general public. Meanwhile, images collected during and after the eclipse will be available to scientists and the public for research purposes. To further engage the public, video clips, film, and a documentary will be produced prior and after the event. A science education research team will work alongside the team to understand how the project supports deeper connections to the eclipse experience.

  14. 2017 Total Solar Eclipse

    NASA Image and Video Library

    2017-08-21

    The Moon is seen passing in front of the Sun at the point of the maximum of the partial solar eclipse near Banner, Wyoming on Monday, Aug. 21, 2017. A total solar eclipse swept across a narrow portion of the contiguous United States from Lincoln Beach, Oregon to Charleston, South Carolina. A partial solar eclipse was visible across the entire North American continent along with parts of South America, Africa, and Europe. Photo Credit: (NASA/Joel Kowsky)

  15. 2017 Total Solar Eclipse

    NASA Image and Video Library

    2017-08-21

    The Moon is seen as it starts passing in front of the Sun during a solar eclipse from Ross Lake, Northern Cascades National Park, Washington on Monday, Aug. 21, 2017. A total solar eclipse swept across a narrow portion of the contiguous United States from Lincoln Beach, Oregon to Charleston, South Carolina. A partial solar eclipse was visible across the entire North American continent along with parts of South America, Africa, and Europe. Photo Credit: (NASA/Bill Ingalls)

  16. Observing the 2017 Total Solar Eclipse from the Pisgah Astronomical Research Institute

    NASA Astrophysics Data System (ADS)

    Kirwan, Sean Matthew; Cline, J. Donald; Krochmal, Mark; Donald Cline, Mark Krochmal

    2017-01-01

    The Pisgah Astronomical Research Institute (PARI) is located directly under the path of totality of next year’s solar eclipse and possesses two 26m radio telescopes capable of interferometry at simultaneously at 2.3 GHz and 8.4 GHZ. PARI is preparing these radio telescopes for use by the astronomical community to observe solar eclipse. We will present the status of PARI’s radio telescopes and information on access for the eclipse. We will also present the status and availability of several optical telescopes.

  17. The August 21, 2017 American total solar eclipse through the eyes of GPS

    NASA Astrophysics Data System (ADS)

    Kundu, Bhaskar; Panda, Dibyashakti; Gahalaut, Vineet K.; Catherine, J. K.

    2018-04-01

    We explored spatio-temporal variation in Total Electron Contents (TEC) in the ionosphere caused by the recent August 21, 2017 total solar eclipse, which was observed over the United States of America. The path of total solar eclipse passes through the continental parts of the United States of America, starting in the northwestern state of Oregon and ending in the southeastern state of South Carolina, approximately covering 4000 km length. Across this length EarthScope Plate Boundary Observatory (PBO) has been operating a dense cGPS/GNSS networks. During the course of passage of the solar eclipse, the sudden decline in solar radiation by temporarily obscuration by the Moon caused a drop of ˜6-9 × 1016 electrons/m2in the ionosphere with time-delay at the cGPS sites. The significant drop in TEC at cGPS sites captured the average migration velocity of shadow along the eclipse path (0.74 km/s), from which we estimated the Moon's orbital velocity (˜1 km/s). Further, this event also caused some marginal increase in TEC during the eclipse in the Earth's ionosphere in the magnetically conjugate region at the tip of South America and Antarctica, consistent with the model predictions of SAMI3 by Naval Research Laboratory.

  18. Symbolism and discovery: eclipses in art.

    PubMed

    Blatchford, Ian

    2016-09-28

    There is a fascinating tradition of depicting solar eclipses in Western art, although these representations have changed over time. Eclipses have often been an important feature of Christian iconography, but valued as much for their biblical significance as for the splendour of the physical event. However, as Western culture passed through the Renaissance and Enlightenment the depictions of eclipses came to reflect new astronomical knowledge and a thirst for rational learning well beyond the confines of the church and other elites. Artists also played a surprisingly important role in helping scientists in the nineteenth century understand and record the full phenomena of an eclipse, even as the advent of photography also came to solve a number of scientific puzzles. In the most recent century, artists have responded to eclipses with symbolism, abstraction and playfulness.This article is part of the themed issue 'Atmospheric effects of solar eclipses stimulated by the 2015 UK eclipse'. © 2016 The Author(s).

  19. 2017 Total Solar Eclipse

    NASA Image and Video Library

    2017-08-21

    The Moon is seen passing in front of the Sun during a total solar eclipse on Monday, August 21, 2017 from onboard a NASA Gulfstream III aircraft flying 25,000 feet above the Oregon coast. A total solar eclipse swept across a narrow portion of the contiguous United States from Lincoln Beach, Oregon to Charleston, South Carolina. A partial solar eclipse was visible across the entire North American continent along with parts of South America, Africa, and Europe. Photo Credit: (NASA/Carla Thomas)

  20. Discovery of Eclipses from the Accreting Millisecond X-Ray Pulsar Swift J1749.4-2807

    NASA Technical Reports Server (NTRS)

    Markwardt, C. B.; Stromhmayer, T. E.

    2010-01-01

    We report the discovery of X-ray eclipses in the recently discovered accreting millisecond X-ray pulsar SWIFT J1749.4-2807. This is the first detection of X-ray eclipses in a system of this type and should enable a precise neutron star mass measurement once the companion star is identified and studied. We present a combined pulse and eclipse timing solution that enables tight constraints on the orbital parameters and inclination and shows that the companion mass is in the range 0.6-0.8 solar mass for a likely range of neutron star masses, and that it is larger than a main-sequence star of the same mass. We observed two individual eclipse egresses and a single ingress. Our timing model shows that the eclipse features are symmetric about the time of 90 longitude from the ascending node, as expected. Our eclipse timing solution gives an eclipse duration (from the mid-points of ingress to egress) of 2172+/-13 s. This represents 6.85% of the 8.82 hr orbital period. This system also presents a potential measurement of "Shapiro" delay due to general relativity; through this technique alone, we set an upper limit to the companion mass of 2.2 Solar mass .

  1. Heliophysics at total solar eclipses

    NASA Astrophysics Data System (ADS)

    Pasachoff, Jay M.

    2017-08-01

    Observations during total solar eclipses have revealed many secrets about the solar corona, from its discovery in the 17th century to the measurement of its million-kelvin temperature in the 19th and 20th centuries, to details about its dynamics and its role in the solar-activity cycle in the 21st century. Today's heliophysicists benefit from continued instrumental and theoretical advances, but a solar eclipse still provides a unique occasion to study coronal science. In fact, the region of the corona best observed from the ground at total solar eclipses is not available for view from any space coronagraphs. In addition, eclipse views boast of much higher quality than those obtained with ground-based coronagraphs. On 21 August 2017, the first total solar eclipse visible solely from what is now United States territory since long before George Washington's presidency will occur. This event, which will cross coast-to-coast for the first time in 99 years, will provide an opportunity not only for massive expeditions with state-of-the-art ground-based equipment, but also for observations from aloft in aeroplanes and balloons. This set of eclipse observations will again complement space observations, this time near the minimum of the solar activity cycle. This review explores the past decade of solar eclipse studies, including advances in our understanding of the corona and its coronal mass ejections as well as terrestrial effects. We also discuss some additional bonus effects of eclipse observations, such as recreating the original verification of the general theory of relativity.

  2. Mapping the 2017 Eclipse: Education, Navigation, Inspiration

    NASA Astrophysics Data System (ADS)

    Zeiler, M.

    2015-12-01

    Eclipse maps are a unique vessel of knowledge. At a glance, they communicate the essential knowledge of where and when to successfully view a total eclipse of the sun. An eclipse map also provides detailed knowledge of eclipse circumstances superimposed on the highway system for optimal navigation, especially in the event that weather forces relocation. Eclipse maps are also a vital planning tool for solar physicists and astrophotographers capturing high-resolution imagery of the solar corona. Michael Zeiler will speak to the role of eclipse maps in educating the American public and inspiring people to make the effort to reach the path of totality for the sight of a lifetime. Michael will review the role of eclipse maps in astronomical research and discuss a project under development, the 2017 Eclipse Atlas for smartphones, tablets, and desktop computers.

  3. There's An App For That: Planning Ahead for the Solar Eclipse in August 2017

    NASA Astrophysics Data System (ADS)

    Chizek Frouard, Malynda R.; Lesniak, Michael V.; Bell, Steve

    2017-01-01

    With the total solar eclipse of 2017 August 21 over the continental United States approaching, the U.S. Naval Observatory (USNO) on-line Solar Eclipse Computer can now be accessed via an Android application, available on Google Play.Over the course of the eclipse, as viewed from a specific site, several events may be visible: the beginning and ending of the eclipse (first and fourth contacts), the beginning and ending of totality (second and third contacts), the moment of maximum eclipse, sunrise, or sunset. For each of these events, the USNO Solar Eclipse 2017 Android application reports the time, Sun's altitude and azimuth, and the event's position and vertex angles. The app also lists the duration of the total phase, the duration of the eclipse, the magnitude of the eclipse, and the percent of the Sun obscured for a particular eclipse site.All of the data available in the app comes from the flexible USNO Solar Eclipse Computer Application Programming Interface (API), which produces JavaScript Object Notation (JSON) that can be incorporated into third-party Web sites or custom applications. Additional information is available in the on-line documentation (http://aa.usno.navy.mil/data/docs/api.php).For those who prefer using a traditional data input form, the local circumstances can still be requested at http://aa.usno.navy.mil/data/docs/SolarEclipses.php.In addition the 2017 August 21 Solar Eclipse Resource page (http://aa.usno.navy.mil/data/docs/Eclipse2017.php) consolidates all of the USNO resources for this event, including a Google Map view of the eclipse track designed by Her Majesty's Nautical Almanac Office (HMNAO).Looking further ahead, a 2024 April 8 Solar Eclipse Resource page (http://aa.usno.navy.mil/data/docs/Eclipse2024.php) is also available.

  4. Eclipsing the Light...Fantastic! Teaching Science.

    ERIC Educational Resources Information Center

    Leyden, Michael B.

    1995-01-01

    Features the concepts of optics and geometry of eclipses. Presents the "eclipse rule," suggesting classroom activities in which students derive this rule. Includes some triangles activities for outdoors that illustrate eclipsing and sighting phenomena. (ET)

  5. Spectral Eclipse Timing

    NASA Astrophysics Data System (ADS)

    Dobbs-Dixon, Ian; Agol, Eric; Deming, Drake

    2015-12-01

    We utilize multi-dimensional simulations of varying equatorial jet strength to predict wavelength-dependent variations in the eclipse times of gas-giant planets. A displaced hot spot introduces an asymmetry in the secondary eclipse light curve that manifests itself as a measured offset in the timing of the center of eclipse. A multi-wavelength observation of secondary eclipse, one probing the timing of barycentric eclipse at short wavelengths and another probing at longer wavelengths, will reveal the longitudinal displacement of the hot spot and break the degeneracy between this effect and that associated with the asymmetry due to an eccentric orbit. The effect of time offsets was first explored in the IRAC wavebands by Williams et al. Here we improve upon their methodology, extend to a broad range of wavelengths, and demonstrate our technique on a series of multi-dimensional radiative-hydrodynamical simulations of HD 209458b with varying equatorial jet strength and hot-spot displacement. Simulations with the largest hot-spot displacement result in timing offsets of up to 100 s in the infrared. Though we utilize a particular radiative hydrodynamical model to demonstrate this effect, the technique is model independent. This technique should allow a much larger survey of hot-spot displacements with the James Webb Space Telescope than currently accessible with time-intensive phase curves, hopefully shedding light on the physical mechanisms associated with thermal energy advection in irradiated gas giants.

  6. Solar eclipses.

    NASA Astrophysics Data System (ADS)

    Livingston, W.

    The occasion of a total eclipse impacts the human observer with a bewildering rapid sequence of phenomena: mid-day cooling, failing light without accustomed color change, shadow-bands transiting the ground, cessation of bird sounds, possible frantic beating of jungle drums, Baily's beads, appearance of flame-like prominences, and most fantastic of all the solar corona. The author considers that although the corona is known to be 2 - 20(106)K, there is a lack of consensus on the heating mechanism, except the energy must be non-thermal and derived from surface and sub-surface convective motions. Theoreticians invoke the Joule dissipation of magnetic fields by Alfvén waves, electric currents in loop structures, or MHD turbulence. Although eclipse experiments to discriminate between these ideas generally fail, the sighting of 'plasmoids' was reported from the CFHT on Mauna Kea at the 1991 eclipse. Future experiments include: IR mapping of the coronal spectrum, spectroscopic velocity measurements, and the continued search for waves, nanoflares, and plasmoids.

  7. Liquid Chromatography with Post-Column Reagent Addition of Ammonia in Methanol Coupled to Negative Ion Electrospray Ionization Tandem Mass Spectrometry for Determination of Phenoxyacid Herbicides and their Degradation Products in Surface Water

    PubMed Central

    Raina, Renata; Etter, Michele L.

    2010-01-01

    A new liquid chromatography (LC)-negative ion electrospray ionization (ESI−)–tandem mass spectrometry (MS/MS) method with post-column addition of ammonia in methanol has been developed for the analysis of acid herbicides: 2,4-dichlorophenoxy acetic acid, 4-chloro-o-tolyloxyacetic acid, 2-(2-methyl-4-chlorophenoxy)butyric acid, mecoprop, dichlorprop, 4-(2,4-dichlorophenoxy) butyric acid, 2,4,5-trichlorophenoxy propionic acid, dicamba and bromoxynil, along with their degradation products: 4-chloro-2-methylphenol, 2,4-dichlorophenol, 2,4,5-trichlorophenol and 3,5-dibromo-4-hydroxybenzoic acid. The samples were extracted from the surface water matrix using solid-phase extraction (SPE) with a polymeric sorbent and analyzed with LC ESI− with selected reaction monitoring (SRM) using a three-point confirmation approach. Chromatography was performed on a Zorbax Eclipse XDB-C18 (50 × 4.6 mm i.d., 1.8 μm) with a gradient elution using water-methanol with 2 mM ammonium acetate mobile phase at a flow rate of 0.15 mL/min. Ammonia in methanol (0.8 M) was added post-column at a flow rate of 0.05 mL/min to enhance ionization of the degradation products in the MS source. One SRM transition was used for quantitative analysis while the second SRM along with the ratio of SRM1/SRM2 within the relative standard deviation determined by standards for each individual pesticide and retention time match were used for confirmation. The standard deviation of ratio of SRM1/SRM2 obtained from standards run on the day of analysis for different phenoxyacid herbicides ranged from 3.9 to 18.5%. Limits of detection (LOD) were between 1 and 15 ng L−1 and method detection limits (MDL) with strict criteria requiring <25% deviation of peak area from best-fit line for both SRM1 and SRM2 ranged from 5 to 10 ng L−1 for acid ingredients (except dicamba at 30 ng L−1) and from 2 to 30 ng L−1 for degradation products. The SPE-LC-ESI− MS/MS method permitted low nanogram-per-liter determination

  8. Fall 2011 Eclipse Season Begins

    NASA Image and Video Library

    2011-09-13

    The Fall 2011 eclipse season started on September 11, 2011. Here is an AIA 304 image from 0658 UT. SDO has eclipse seasons twice a year near each equinox. For three weeks near midnight Las Cruces time (about 0700 UT) our orbit has the Earth pass between SDO and the Sun. These eclipses can last up to 72 minutes in the middle of an eclipse season. The current eclipse season started on September 11 and lasts until October 4. To read more about SDO go to: sdo.gsfc.nasa.gov/ Credit: NASA/GSFC/SDO 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

  9. Kepler eclipsing binary stars. IV. Precise eclipse times for close binaries and identification of candidate three-body systems

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

    Conroy, Kyle E.; Stassun, Keivan G.; Prša, Andrej

    2014-02-01

    We present a catalog of precise eclipse times and analysis of third-body signals among 1279 close binaries in the latest Kepler Eclipsing Binary Catalog. For these short-period binaries, Kepler's 30 minute exposure time causes significant smearing of light curves. In addition, common astrophysical phenomena such as chromospheric activity, as well as imperfections in the light curve detrending process, can create systematic artifacts that may produce fictitious signals in the eclipse timings. We present a method to measure precise eclipse times in the presence of distorted light curves, such as in contact and near-contact binaries which exhibit continuously changing light levelsmore » in and out of eclipse. We identify 236 systems for which we find a timing variation signal compatible with the presence of a third body. These are modeled for the light travel time effect and the basic properties of the third body are derived. This study complements J. A. Orosz et al. (in preparation), which focuses on eclipse timing variations of longer period binaries with flat out-of-eclipse regions. Together, these two papers provide comprehensive eclipse timings for all binaries in the Kepler Eclipsing Binary Catalog, as an ongoing resource freely accessible online to the community.« less

  10. ScienceCast 163: A Colorful Lunar Eclipse

    NASA Image and Video Library

    2014-09-17

    Mark your calendar: On Oct. 8th, the Moon will pass through the shadow of Earth for a total lunar eclipse. Sky watchers in the USA will see the Moon turn a beautiful shade of celestial red and maybe turquoise, too.

  11. MARVELS Radial Velocity Solutions to Seven Kepler Eclipsing Binaries

    NASA Astrophysics Data System (ADS)

    Heslar, Michael Francis; Thomas, Neil B.; Ge, Jian; Ma, Bo; Herczeg, Alec; Reyes, Alan; SDSS-III MARVELS Team

    2016-01-01

    Eclipsing binaries serve momentous purposes to improve the basis of understanding aspects of stellar astrophysics, such as the accurate calculation of the physical parameters of stars and the enigmatic mass-radius relationship of M and K dwarfs. We report the investigation results of 7 eclipsing binary candidates, initially identified by the Kepler mission, overlapped with the radial velocity observations from the SDSS-III Multi-Object APO Radial-Velocity Exoplanet Large-Area Survey (MARVELS). The RV extractions and spectroscopic solutions of these eclipsing binaries were generated by the University of Florida's 1D data pipeline with a median RV precision of ~60-100 m/s, which was utilized for the DR12 data release. We performed the cross-reference fitting of the MARVELS RV data and the Kepler photometric fluxes obtained from the Kepler Eclipsing Binary Catalog (V2) and modelled the 7 eclipsing binaries in the BinaryMaker3 and PHOEBE programs. This analysis accurately determined the absolute physical and orbital parameters of each binary. Most of the companion stars were determined to have masses of K and M dwarf stars (0.3-0.8 M⊙), and allowed for an investigation into the mass-radius relationship of M and K dwarfs. Among the cases are KIC 9163796, a 122.2 day period "heartbeat star", a recently-discovered class of eccentric binaries known for tidal distortions and pulsations, with a high eccentricity (e~0.75) and KIC 11244501, a 0.29 day period, contact binary with a double-lined spectrum and mass ratio (q~0.45). We also report on the possible reclassification of 2 Kepler eclipsing binary candidates as background eclipsing binaries based on the analysis of the flux measurements, flux ratios of the spectroscopic and photometric solutions, the differences in the FOVs, the image processing of Kepler, and RV and spectral analysis of MARVELS.

  12. 8-Micron Photometry of the "Hot Saturn" HD 149026b During Its Secondary Eclipse

    NASA Astrophysics Data System (ADS)

    Harrington, Joseph; Deming, Drake; Richardson, Jeremy; Seager, Sara; Cho, James; Hansen, Bradley; Menou, Kristen

    2005-07-01

    We will measure the flux of the newly-discovered extrasolar planet HD149026b in the 8-micron IRAC bandpass during its secondary eclipse. The observation lasts 6 hours. HD 149026b is a transiting "hot Saturn" planet that was announced on 1 July 2005 (Sato et al. 2005). The planet is unusual for its small size and high density. At 0.725 Rj and 0.36 Mj, it is 1.7 times as dense as Saturn. Models predict that it must have a heavy-element core of 67-78 Earth masses, and that the core should extend more than half the distance to the surface, not unlike Neptune's and Uranus's cores. This unusual composition could result in substantially different atmospheric minor constituents, albedo, chemistry, and dynamics from those of any other planet. It thus bears immediate study, both for its own sake and to provide the basic flux numbers needed to plan follow-on studies in GO Cycles 3, 4, and 5. We have demonstrated that we can analyze and publish such data very quickly: manuscript submission for our Spitzer MIPS-24 detection of HD 209458b during its secondary eclipse (Deming et al. 2005b) took under two months from the receipt of data, without the benefit of pre-existing similar analyses, such as we now have. There had previously been no direct detection of light from an extrasolar planet. These pioneering measurements of HD 149026b's fluxes will give us two fluxes temperatures and possibly an H2O band depth. These will strongly constrain the many competing radiative, chemical, and dynamical models that are certain to appear in short order.

  13. Student artistry sparks eclipse excitement on Maui: NSO/DKIST EPO for the 2016 Partial Solar Eclipse

    NASA Astrophysics Data System (ADS)

    Schad, Thomas A.; Penn, Matthew J.; Armstrong, James

    2016-05-01

    Local creativity and artistry is a powerful resource that enhances education programs and helps us generate excitement for science within our communities. In celebration of the 2016 Solar Eclipse, the National Solar Observatory (NSO) and its Daniel K Inouye Solar Telescope (DKIST) project were pleased to engage with students across Maui County, Hawai`i, via the 2016 Maui Eclipse Art Contest. With the help of the Maui Economic Development Board and the University of Hawai'is Institute for Astronomy, we solicited art entries from all K-12 schools in Maui County approximately 6 months prior to the eclipse. Along with divisional prizes, a grand prize was selected by a panel of local judges, which was subsequently printed on 25,000 solar eclipse viewing glasses and distributed to all Maui students. We found that the impact of a locally-sourced glasses design cannot be understated. Overall, the success of this program relied upon reaching out to individual teachers, supplying educational flyers to all schools, and visiting classrooms. On the day of the eclipse, all of the art entries were prominently displayed during a community eclipse viewing event at Kalama Beach Park in Kihei, HI, that was co-hosted by NSO and the Maui Science Center. This eclipse art contest was integral to making local connections to help promote science education on Maui, and we suggest that it could be adapted to the solar community's EPO activities for the upcoming 2017 Great American Solar Eclipse.

  14. Discovery of deep eclipses in the cataclysmic variable IPHAS J051814.33+294113.0

    NASA Astrophysics Data System (ADS)

    Kozhevnikov, V. P.

    2018-06-01

    Performing the photometric observations of the cataclysmic variable IPHAS J051814.33+294113.0, we discovered very deep eclipses. The observations were obtained over 14 nights, had a total duration of 56 hours and covered one year. The large time span, during which we observed the eclipses, allowed us to measure the orbital period in IPHAS J051814.33+294113.0 with high precision, P_{orb}=0.20603098± 0.00000025 d. The prominent parts of the eclipses lasted 0.1± 0.01 phases or 30± 3 min. The depth of the eclipses was variable in the range 1.8-2.9 mag. The average eclipse depth was equal to 2.42± 0.06 mag. The prominent parts of the eclipses revealed a smooth and symmetric shape. We derived the eclipse ephemeris, which, according to the precision of the orbital period, has a formal validity time of 500 years. This ephemeris can be useful for future investigations of the long-term period changes. During the latter four observational nights in 2017 January, we observed the sharp brightness decrease of IPHAS J051814.33+294113.0 by 2.3 mag. This brightness decrease imitated the end of the dwarf nova outburst. However, the long-term light curve of IPHAS J051814.33+294113.0 obtained in the course of the Catalina Sky Survey during 8 years showed no dwarf nova outbursts. From this we conclude that IPHAS J051814.33+294113.0 is a novalike variable. Moreover, the sharp brightness decrease, which we observed in IPHAS J051814.33+294113.0, suggests that this novalike variable belongs to the VY Scl-subtype. Due to very deep eclipses, IPHAS J051814.33+294113.0 is suitable to study the accretion disc structure using eclipse mapping techniques. Because this novalike variable has the long orbital period, it is of interest to determine the masses of the stellar components from radial velocity measurements. Then, our precise eclipse ephemeris can be useful to the phasing of spectroscopic data.

  15. Record-Breaking Eclipsing Binary

    NASA Astrophysics Data System (ADS)

    Kohler, Susanna

    2016-05-01

    A new record holder exists for the longest-period eclipsing binary star system: TYC-2505-672-1. This intriguing system contains a primary star that is eclipsed by its companion once every 69 years with each eclipse lasting several years!120 Years of ObservationsIn a recent study, a team of scientists led by Joseph Rodriguez (Vanderbilt University) characterizes the components of TYC-2505-672-1. This binary star system consists of an M-type red giant star that undergoes a ~3.45-year-long, near-total eclipse with a period of ~69.1 years. This period is more than double that of the previous longest-period eclipsing binary!Rodriguez and collaborators combined photometric observations of TYC-2505-672-1 by the Kilodegree Extremely Little Telescope (KELT) with a variety of archival data, including observations by the American Association of Variable Star Observers (AAVSO) network and historical data from the Digital Access to a Sky Century @ Harvard (DASCH) program.In the 120 years spanned by these observations, two eclipses are detected: one in 1942-1945 and one in 2011-2015. The authors use the observations to analyze the components of the system and attempt to better understand what causes its unusual light curve.Characterizing an Unusual SystemObservations of TYC-2505-672-1 plotted from 1890 to 2015 reveal two eclipses. (The blue KELT observations during the eclipse show upper limits only.) [Rodriguez et al. 2016]By modeling the systems emission, Rodriguez and collaborators establish that TYC-2505-672-1 consists of a 3600-K primary star thats the M giant orbited by a small, hot, dim companion thats a toasty 8000 K. But if the companion is small, why does the eclipse last several years?The authors argue that the best model of TYC-2505-672-1 is one in which the small companion star is surrounded by a large, opaque circumstellar disk. Rodriguez and collaborators suggest that the companion could be a former red giant whose atmosphere was stripped from it, leaving behind

  16. Solar Eclipse from NASA Goddard

    NASA Image and Video Library

    2017-08-21

    View of the partial solar eclipse from NASA's Goddard Space Flight Center in Greenbelt, Md on Monday, August 21, 2017. A total solar eclipse swept across a narrow portion of the contiguous United States from Lincoln Beach, Oregon to Charleston, South Carolina. A partial solar eclipse was visible across the entire North American continent along with parts of South America, Africa, and Europe. Credit: NASA/Goddard/Rebecca Roth

  17. Eclipses and the Olympics

    NASA Astrophysics Data System (ADS)

    Pang, K. D.; Yau, K. K.

    2000-12-01

    Like returns of Halley's comet the Olympic games occur periodically, though not as regularly in antiquity. Dates were also imprecise due to the chaotic calendars in use. Reported sightings of comets and eclipses can be used with game dates to help fix ancient events. However some reported darkening of the sun, e.g., after Julius Caesar's murder in 44 BC, was due to volcanic eruptions. A red comet, visible in daylight, first appeared during the games that year. It was also seen from China and Korea (Pang, Sciences 31, 30). Phlegon's ``Olympiads" (2nd century) says that Christ's crucifixion was in the 4th year of the 202nd Olympiad (AD 29-33), when a total solar eclipse occurred in the 6th hour. Only the Nov. 24, AD 29 eclipse over Asia Minor can match that, and Joel's prophecy (Acts 2, 14-21) that ``the sun will be turned to darkness and moon to blood." However it conflicts with ``the first day of Passover," as recorded by Mathew, Mark and Luke, i.e., full moon in early spring. Humphreys and Waddington (Nature 306, 743) have suggested meteorological darkening and the April 3, AD 33 lunar eclipse instead. Schaefer has questioned the eclipse's visibility from Jerusalem (31.46N, 35.14E). The six computations he cited gave dissimilar answers due to the imprecise rates of the secular lunar acceleration, and lengthening of the day used (Q.Jl.R.astr.Soc. 31, 53). Lunar laser ranging has since fixed the former at -26"/cen2. Analysis of ancient Chinese solar eclipse records, e.g., the April 21, 899 BC and April 4, AD 368 ``double dawns" over Zheng, has given us a delta T (in sec) = 30t2, where t is centuries before 1800 (Pang, Yau and Chou, in ``Dynamics of Ice Age Earth: A Modern Perspective," 1998). Our computations show that the moon rose over Jerusalem, with 1/3 still in the umbra and the rest in penumbra. Holdover meteorological darkening with long absorption air mass could have help reddened the moon also. Finally the first ``eclipse season" (the Aug. 21 lunar, and

  18. The 1984 eclipse of the symbiotic binary SY Muscae

    NASA Technical Reports Server (NTRS)

    Kenyon, S. J.; Michalitisianos, A. G.; Lutz, J. H.; Kafatos, M.

    1985-01-01

    Data from IUE spectra obtained with the 10 x 20-arcsec aperture on May 13, 1984, and optical spectrophotometry obtained with an SIT vidicon on the 1.5-m telescope at CTIO on April 29-May 1, 1984, are reported for the symbiotic binary SY Mus. The data are found to be consistent with a model of a red-giant secondary of 60 solar radii which completely eclipses the hot primary every 627 d but only partially eclipses the 75-solar-radius He(+) region surrounding the primary. The distance to SY Mus is estimated as 1.3 kpc. It is suggested that the large Balmer decrement in eclipse, with (H-alpha)/(H-beta) = 8.3 and (H-beta)/(H-gamma) = 1.5, is associated with an electron density of about 10 to the 10th/cu cm.

  19. KEPLER ECLIPSING BINARIES WITH STELLAR COMPANIONS

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

    Gies, D. R.; Matson, R. A.; Guo, Z.

    2015-12-15

    Many short-period binary stars have distant orbiting companions that have played a role in driving the binary components into close separation. Indirect detection of a tertiary star is possible by measuring apparent changes in eclipse times of eclipsing binaries as the binary orbits the common center of mass. Here we present an analysis of the eclipse timings of 41 eclipsing binaries observed throughout the NASA Kepler mission of long duration and precise photometry. This subset of binaries is characterized by relatively deep and frequent eclipses of both stellar components. We present preliminary orbital elements for seven probable triple stars amongmore » this sample, and we discuss apparent period changes in seven additional eclipsing binaries that may be related to motion about a tertiary in a long period orbit. The results will be used in ongoing investigations of the spectra and light curves of these binaries for further evidence of the presence of third stars.« less

  20. 2017 Solar Eclipse Event

    NASA Image and Video Library

    2017-06-11

    Former Spacelab 1 Mission scientist Rick Chappell views the August 21, 2017 solar eclipse with his wife. Chappell, a former associate director for science at Marshall and now a physics professor at Vanderbilt University in Nashville, joined a throng of Marshall personnel to marvel at the eclipse.

  1. Closeup of QF-106 release hook for Eclipse program

    NASA Technical Reports Server (NTRS)

    1997-01-01

    View of the release hook on the QF-106 that allowed the pilot to release the tow rope extending from the C-141A tow plane in the Eclipse project. In 1997 and 1998, the Dryden Flight Research Center at Edwards, California, supported and hosted a Kelly Space & Technology, Inc. project called Eclipse, which sought to demonstrate the feasibility of a reusable tow-launch vehicle concept. The project goal was to successfully tow, inflight, a modified QF-106 delta-wing aircraft with an Air Force C-141A transport aircraft. This would demonstrate the possibility of towing and launching an actual launch vehicle from behind a tow plane. Dryden was the responsible test organization and had flight safety responsibility for the Eclipse project. Dryden provided engineering, instrumentation, simulation, modification, maintenance, range support, and research pilots for the test program. The Air Force Flight Test Center (AFFTC), Edwards, California, supplied the C-141A transport aircraft and crew and configured the aircraft as needed for the tests. The AFFTC also provided the concept and detail design and analysis as well as hardware for the tow system and QF-106 modifications. Dryden performed the modifications to convert the QF-106 drone into the piloted EXD-01 (Eclipse eXperimental Demonstrator-01) experimental aircraft. Kelly Space & Technology hoped to use the results gleaned from the tow test in developing a series of low-cost, reusable launch vehicles. These tests demonstrated the validity of towing a delta-wing aircraft having high wing loading, validated the tow simulation model, and demonstrated various operational procedures, such as ground processing of in-flight maneuvers and emergency abort scenarios.

  2. Fifty year canon of solar eclipses: 1986 - 2035

    NASA Technical Reports Server (NTRS)

    Espenak, Fred

    1987-01-01

    A complete catalog is presented, listing the general characteristics of every solar eclipse from 1901 through 2100. To complement this catalog, a detailed set of cylindrical projection world maps shows the umbral paths of every solar eclipse over the 200 year interval. Focusing in on the next 50 years, accurate geodetic path coordinates and local circumstances for the 71 central eclipses from 1987 through 2035 are tabulated. Finally, the geodetic paths of the umbral and penumbral shadows of all 109 solar eclipses in this period are plotted on orthographic projection maps of the Earth. Appendices are included which discuss eclipse geometry, eclipse frequency and occurrence, modern eclipse prediction and time determination. Finally, code for a simple Fortran program is given to predict the occurrence and characteristics of solar eclipses.

  3. 2017 Total Solar Eclipse

    NASA Image and Video Library

    2017-08-21

    This composite image of seven pictures shows the progression of a partial solar eclipse near from Ross Lake, Northern Cascades National Park, Washington on Monday, Aug. 21, 2017. The second to the last frame shows the International Space Station, with a crew of six onboard, in silhouette as it transits the Sun at roughly five miles per second. A total solar eclipse swept across a narrow portion of the contiguous United States from Lincoln Beach, Oregon to Charleston, South Carolina. A partial solar eclipse was visible across the entire North American continent along with parts of South America, Africa, and Europe. Photo Credit: (NASA/Bill Ingalls)

  4. Preparing for the Eclipse

    ERIC Educational Resources Information Center

    Hurst, Anna; Plummer, Julia; Gurton, Suzanne; Schatz, Dennis

    2017-01-01

    On August 21, 2017, sky gazers all across North America will experience a total solar eclipse, arguably the most breathtaking of all astronomical phenomena. The August eclipse is an ideal astronomical event to observe with young children because it allows them to observe a powerful and easily accessible astronomical phenomenon. Observing…

  5. Super Blood Moon Lunar Eclipse

    NASA Image and Video Library

    2017-12-08

    CLOUDY with a chance of NOT SEEING the Super Blood Moon Lunar Eclipse? WATCH Live here: bit.ly/1LfspfW No worries, we've got you've covered. Click on over to the live stream starting at 8:00 p.m. until at least 11:30 p.m. EDT broadcast from NASA's Marshall Space Flight Center in Huntsville, Ala., with a live feed from the Griffith Observatory, Los Angeles, Calif. Mitzi Adams, a NASA solar physicist at Marshall will discuss the eclipse and answer questions on Twitter. To ask a question, use ‪#‎askNASA‬. 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

  6. 2017 Solar Eclipse Event

    NASA Image and Video Library

    2017-06-11

    Former Spacelab 1 mission scientist Rick Chappell addresses Marshall team members during the Aug. 21 eclipse-watching event in Activities Building 4316. Chappell, a former associate director for science at Marshall and now a physics professor at Vanderbilt University in Nashville, joined a throng of Marshall personnel to marvel at the eclipse.

  7. Fifty Year Canon of Lunar Eclipses: 1986-2035

    NASA Technical Reports Server (NTRS)

    Espenak, Fred

    1989-01-01

    A complete catalog is presented, listing the general circumstances of every lunar eclipse from 1901 through 2100. To compliment this catalog, a set of figures illustrate the basic Moon-shadow geometry and global visibility for every lunar eclipse over the 200 year interval. Focusing in on the next fifty years, 114 detailed diagrams show the Moon's path through Earth's shadow during every eclipse, including contact times at each phase. The accompanying cylindrical projection maps of Earth show regions of hemispheric visibility for all phases. The appendices discuss eclipse geometry, eclipse frequency and recurrence, enlargement of Earth's shadow, crater timings, eclipse brightness and time determination. Finally, a simple FORTRAN program is provided which can be used to predict the occurrence and general characteristics of lunar eclipses. This work is a companion volume to NASA Reference Publication 1178: Fifty Year Canon of Solar Eclipses: 1986-2035.

  8. N-(ferrocenecarbonyl)-N'-(quinolin-8-yl)thiourea.

    PubMed

    Yang, Jia-Xiang; Tian, Yu-Peng; Liu, Qing-Liang; Xie, Yong-Shu; Fun, Hoong-Kun; Chantrapromma, Suchada; Razak, Ibrahim Abdul

    2002-01-01

    In the title compound, [Fe(C5H5)(C16H12N3OS)], the 8-aminoquinoline and acylthiourea moieties are almost planar. There are two perpendicular arrangements of the molecules in the crystal with slightly different conformations. The two cyclopentadienyl rings in each molecule are parallel and eclipsed.

  9. A NEW CLASS OF NASCENT ECLIPSING BINARIES WITH EXTREME MASS RATIOS

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

    Moe, Maxwell; Stefano, Rosanne Di, E-mail: mmoe@cfa.harvard.edu

    2015-03-10

    Early B-type main-sequence (MS) stars (M {sub 1} ≈ 5-16 M {sub ☉}) with closely orbiting low-mass stellar companions (q = M {sub 2}/M {sub 1} < 0.25) can evolve to produce Type Ia supernovae, low-mass X-ray binaries, and millisecond pulsars. However, the formation mechanism and intrinsic frequency of such close extreme mass-ratio binaries have been debated, especially considering none have hitherto been detected. Utilizing observations of the Large Magellanic Cloud galaxy conducted by the Optical Gravitational Lensing Experiment, we have discovered a new class of eclipsing binaries in which a luminous B-type MS star irradiates a closely orbiting low-massmore » pre-MS companion that has not yet fully formed. The primordial pre-MS companions have large radii and discernibly reflect much of the light they intercept from the B-type MS primaries (ΔI {sub refl} ≈ 0.02-0.14 mag). For the 18 definitive MS + pre-MS eclipsing binaries in our sample with good model fits to the observed light-curves, we measure short orbital periods P = 3.0-8.5 days, young ages τ ≈ 0.6-8 Myr, and small secondary masses M {sub 2} ≈ 0.8-2.4 M {sub ☉} (q ≈ 0.07-0.36). The majority of these nascent eclipsing binaries are still associated with stellar nurseries, e.g., the system with the deepest eclipse ΔI {sub 1} = 2.8 mag and youngest age τ = 0.6 ± 0.4 Myr is embedded in the bright H II region 30 Doradus. After correcting for selection effects, we find that (2.0 ± 0.6)% of B-type MS stars have companions with short orbital periods P = 3.0-8.5 days and extreme mass ratios q ≈ 0.06-0.25. This is ≈10 times greater than that observed for solar-type MS primaries. We discuss how these new eclipsing binaries provide invaluable insights, diagnostics, and challenges for the formation and evolution of stars, binaries, and H II regions.« less

  10. Cognitive aspects of ancient Maya eclipse theory.

    NASA Astrophysics Data System (ADS)

    Closs, M. P.

    This paper is concerned with determining the nature of eclipse phenomena as it was perceived by the ancient Maya. It approaches the problem by considering the linguistic information pertaining to eclipses and by exploring the traditional beliefs associated with the occurrence of eclipses among the postconquest Maya. These data yield a model of a native eclipse theory which is compatible with hieroglyphic and iconographic materials pertaining to the ancient Maya.

  11. Raspberry Pi Eclipse Experiments

    NASA Astrophysics Data System (ADS)

    Chizek Frouard, Malynda

    2018-01-01

    The 21 August 2017 solar eclipse was an excellent opportunity for electronics and science enthusiasts to collect data during a fascinating phenomenon. With my recent personal interest in Raspberry Pis, I thought measuring how much the temperature and illuminance changes during a total solar eclipse would be fun and informational.Previous observations of total solar eclipses have remarked on the temperature drop during totality. Illuminance (ambient light) varies over 7 orders of magnitude from day to night and is highly dependent on relative positions of Sun, Earth, and Moon. I wondered whether totality was really as dark as night.Using a Raspberry Pi Zero W, a Pimoroni Enviro pHAT, and a portable USB charger, I collected environmental temperature; CPU temperature (because the environmental temperature sensor sat very near the CPU on the Raspberry Pi); barometric pressure; ambient light; R, G, and B colors; and x, y, and z acceleration (for marking times when I moved the sensor) data at a ~15 second cadence starting at about 5 am until 1:30 pm from my eclipse observation site in Glendo, WY. Totality occurred from 11:45 to 11:47 am, lasting about 2 minutes and 30 seconds.The Raspberry Pi recorded a >20 degree F drop in temperature during the eclipse, and the illuminance during totality was equivalent to twilight measurements earlier in the day. A limitation in the ambient light sensor prevented accurate measurements of broad daylight and most of the partial phase of the eclipse, but an alternate ambient light sensor combined with the Raspberry Pi setup would make this a cost-efficient set-up for illuminance studies.I will present data from the ambient light sensor, temperature sensor, and color sensor, noting caveats from my experiments, lessons learned for next time, and suggestions for anyone who wants to perform similar experiments for themselves or with a classroom.

  12. An Outreach Project to Provide 2.1 Million Eclipse Glasses and Eclipse Information through 7,100 Libraries Nationwide

    NASA Astrophysics Data System (ADS)

    Fraknoi, Andrew; Schatz, Dennis; Dusenbery, Paul; Duncan, Douglas; Holland, Anne; Laconte, Keliann

    2018-01-01

    With support from the Moore Foundation, Google, the Research Corporation, and NASA, we were able to distribute about 2.1 million eclipse glasses and an extensive booklet of eclipse information and outreach suggestions to 7,100 public libraries throughout the nation. It appears that this project was the single largest program to provide glasses and eclipse information to the public in the U.S. The project using (and significantly enlarged) the existing STARNet network of libraries set up and maintained by the Space Science Institute. We were able to get glasses to a diverse set of institutions, including urban, rural, Native American, small town and large city libraries. In this poster, we will summarize the history of the project, the various components and how they worked together, and the results of a post survey of the librarians, which provided numbers, photographs, and impressions from the many libraries and their patrons. A map of the libraries involved is at www.starnetlibraries.org/2017eclipse/. The booklet of information that was sent to help train librarians in eclipse science and eclipse outreach can still be downloaded free at: http://www.starnetlibraries.org/EclipseGuide/.”

  13. Observing Solar Eclipses in the Developing World

    NASA Astrophysics Data System (ADS)

    Pasachoff, J. M.

    2006-08-01

    The paths of totality of total solar eclipses cross the world, with each spot receiving such a view about every 300 years. The areas of the world from which partial eclipses are visible are much wider. For the few days prior to a total eclipse, the attention of a given country is often drawn toward the eclipse, providing a teachable moment that we can use to bring astronomy to the public's attention. Also, it is important to describe how to observe the partial phases of the eclipse safely. Further, it is important to describe to those people in the zone of totality that it is not only safe but also interesting to view totality. Those who are misled by false warnings that overstate the hazards of viewing the eclipse, or that fail to distinguish between safe and unsafe times for naked-eye viewing, may well be skeptical when other health warnings--perhaps about AIDS or malaria prevention or polio inoculations--come from the authorities, meaning that the penalties for misunderstanding the astronomical event can be severe. Through the International Astronomical Union's Working Group on Solar Eclipses and through the I.A.U.'s Program Group on Public Education at the Times of Eclipses, part of the Commission on Education and Development, we make available information to national authorities, to colleagues in the relevant countries, and to others, through our Websites at http://www.eclipses.info and http://www.totalsolareclipse.net and through personal communication. Among our successes at the 29 March 2006 total solar eclipse was the distribution through a colleague in Nigeria of 400,000 eye-protection filters.

  14. Visual timinigs of four 2015 mutual eclipses of Galileian satellites compared with the ephemerides

    NASA Astrophysics Data System (ADS)

    Sigismondi, Costantino

    2016-05-01

    The nodes of the orbits of the satellites of Jupiter each 6 years are aligned with the axis Sun-Jupiter and mutual eclipses and occultations (PHEMU) occur in series, and their observations help to improve the ephemerides, influenced -on the long period- by many bodies interactions, relativistic corrections and internal mass distributions. The visual observations made in Rome of Ganymedes eclipsed on 20 and 27 Feb and Europa eclipsed on 26 February and 8 May 2015 are compared with the ephemerides. They have 10s accuracy in time, and 0.1 magnitudes in photometry, with a luminosity scale "brighter than", "equal to", "dimmer than" relative to uneclipsed satellites. The paper is structured in 1. Introduction to the mutual phenomena as geometrical consequence of orbital momentum conservations. 2. Visual observations with 3'' telescopes and lack of scotopic vision under city lights. 3. The results of 20, 26 and 27 Feb and 8 May eclipses with relative photometry 4. Accuracy on timing and magnitude of the center of the eclipse; comparison with four ephemerides: IMCCE, BAA (computed by Jean Meeus), Belgian Observatory ephemerides, and Occult 4; 5. Conclusions. Significant departures from the ephemerides have been found either in time,1min,and magnitudes,0.5mag.

  15. 2017 Solar Eclipse Event

    NASA Image and Video Library

    2017-06-11

    Marshall Space Flight Center employees view the August 21, 2017 solar eclipse at the center’s activities building. The Huntsville area experienced 97 percent occultation, nearly a complete blocking out of the sun by the orbit of Earth's moon. The next opportunity to view a solar eclipse in the eastern and central United States will occur in April 2024.

  16. 2017 Total Solar Eclipse

    NASA Image and Video Library

    2017-08-21

    A total solar eclipse is seen on Monday, August 21, 2017 from onboard a NASA Armstrong Flight Research Center’s Gulfstream III 25,000 feet above the Oregon coast. A total solar eclipse swept across a narrow portion of the contiguous United States from Lincoln Beach, Oregon to Charleston, South Carolina. Photo Credit: (NASA/Carla Thomas)

  17. Solar Eclipse 2017

    NASA Image and Video Library

    2017-08-21

    From the Kennedy Space Center Visitor Complex, guests joined Americans from coast to coast following the solar eclipse. Although a partial eclipse on Florida's Space Coast, young and old alike found many ways to watch the rare astronomical event. As the Moon passed between Earth and the midafternoon Sun, a shadow moved across the landscape. The 70-mile-wide totality path, or "umbral cone" -- where the entire Sun will vanish behind the Moon -- stretched across 14 states, from Oregon to South Carolina.

  18. Envelopes in eclipsing binary stars

    NASA Technical Reports Server (NTRS)

    Huang, S.

    1972-01-01

    Theoretical research on eclipsing binaries is presented. The specific areas of investigation are the following: (1) the relevance of envelopes to the study of the light curves of eclipsing binaries, (2) the disk envelope, and (3) the spherical envelope.

  19. Candidates of eclipsing multiples based on extraneous eclipses on binary light curves: KIC 7622486, KIC 7668648, KIC 7670485 and KIC 8938628

    NASA Astrophysics Data System (ADS)

    Zhang, Jia; Qian, Sheng-Bang; He, Jian-Duo

    2017-02-01

    Four candidates of eclipsing multiples, based on new extraneous eclipses found on Kepler binary light curves, are presented and studied. KIC 7622486 is a double eclipsing binary candidate with orbital periods of 2.2799960 d and 40.246503 d. The two binary systems do not eclipse each other in the line of sight, but there is mutual gravitational influence between them which leads to the small but definite eccentricity of 0.0035(0.0022) associated with the short 2.2799960 d period orbit. KIC 7668648 is a hierarchical quadruple system candidate, with two sets of solid 203 ± 5 d period extraneous eclipses and another independent set of extraneous eclipses. A clear and credible extraneous eclipse is found on the binary light curve of KIC 7670485 which makes it a triple system candidate. Two sets of extraneous eclipses with periods of about 390 d and 220 d are found on KIC 8938628 binary curves, which not only confirm the previous conclusion of the 388.5 ± 0.3 triple system, but also indicate new additional objects that make KIC 8938628 a hierarchical quadruple system candidate. The results from these four candidates will contribute to the field of eclipsing multiples.

  20. Eclipse Megamovie 2017: How did we do?

    NASA Astrophysics Data System (ADS)

    Hudson, Hugh; Bender, Mark; Collier, Braxton; Johnson, Calvin; Koh, Justin; Konerding, David; Martinez Oliveros, Juan Carlos; Peticolas, Laura; White, Vivian; Zevin, Dan

    2018-01-01

    The Eclipse Megamovie program, as set up for the Great American Eclipse of 21 August 2017, achived a massive volunteer participation, making maximal use existing equipment but with coordinated training. Everything worked fine, and the archive entered the public domain on Friday, October 6. It comprises about 800 GB of data from DSLR cameras and telescopes. An additional 200 GB of data were obtained by smartphone cameras operating a dedicated free app. The massive oversampling made possible by the many (about 2500) volunteer observers has opened new parameter space for tracking coronal and chromospheric time development. Fortuitously some solar activity appeared during the 90-minute period of totality, including a C-class flare and an ongoing CME. At the smartphone level, with the advantage of precise GPS timing, we have data on solar structure via the timing of Baily's Beads at the 2nd and 3rd contacts. The Megamovie archive is an historical first, and we hope that it has already been a springboard for citizen-science projects. We discuss the execution of the program, presenting some of the 2017 science plans and results. We expect that the eclipse of 2024 will be better still.

  1. Solar Eclipses and the International Year of Astronomy

    NASA Astrophysics Data System (ADS)

    Pasachoff, Jay M.

    2009-05-01

    Solar eclipses capture the attention of millions of people in the countries from which they are visible and provide a major opportunity for public education, in addition to the scientific research and student training that they provide. The 2009 International Year of Astronomy began with an annular eclipse visible from Indonesia on 26 January, with partial phases visible also in other parts of southeast Asia. On 22 July, a major and unusually long total solar eclipse will begin at dawn in India and travel across China, with almost six minutes of totality visible near Shanghai and somewhat more visible from Japanese islands and from ships at sea in the Pacific. Partial phases will be visible from most of eastern Asia, from mid-Sumatra and Borneo northward to mid-Siberia. Eclipse activities include many scientific expeditions and much ecotourism to Shanghai, Hangzhou, and vicinity. My review article on "Eclipses as an Astrophysical Laboratory" will appear in Nature as part of their IYA coverage. Our planetarium presented teacher workshops and we made a film about solar research. Several new books about the corona or eclipses are appearing or have appeared. Many articles are appearing in astronomy magazines and other outlets. Eclipse interviews are appearing on the Planetary Society's podcast "365 Days of Astronomy" and on National Geographic Radio. Information about the eclipse and safe observation of the partial phases are available at http://www.eclipses.info, the Website of the International Astronomical Union's Working Group on Solar Eclipses and of its Program Group on Public Education at the Times of Eclipses of its Commission on Education and Development. The Williams College Expedition to the 2009 Eclipse in the mountains near Hangzhou, China, is supported in part by a grant from the Committee for Research and Exploration of the National Geographic Society. E/PO workshops were supported by NASA.

  2. Eclipses and Eye Safety

    ERIC Educational Resources Information Center

    Fulco, Charles

    2017-01-01

    The 2017 Total Solar Eclipse (TSE2017) will occur on August 21 in the continental United States, bringing totality to this area for the first time since 1979. The Moon's umbra will traverse from Oregon to South Carolina in about 90 minutes, bringing an eerie darkness to 14 states coast-to-coast and a partial eclipse to every part of the country…

  3. 2017 Solar Eclipse Event

    NASA Image and Video Library

    2017-06-11

    Marshall Space Flight Center employee, Phillip Domen, safely views the August 21, 2017 solar eclipse with his homemade viewing box. The Huntsville area experienced 97 percent occultation, nearly a complete blocking out of the sun by the orbit of Earth's moon. The next opportunity to view a solar eclipse in the eastern and central United States will occur in April 2024.

  4. Report of the IAU Working Group on Solar Eclipses

    NASA Astrophysics Data System (ADS)

    Pasachoff, Jay M.

    2015-08-01

    The Working Group on Solar Eclipses coordinates scientists and information in the study of the Sun and the heliosphere at solar eclipses. Our Website at http://eclipses.info has a wide variety of information, including links to maps and other websites dealing with solar eclipses, as well as information on how to observe the partial-phases of solar eclipses safely and why it is interesting for not only scientists but also for the public to observe eclipses and to see how we work to uncover the mysteries of the sun's upper atmosphere. In the last triennium, there were total eclipses in Australia and the Pacific in 2012; in an arc across Africa from Gabon to Uganda and Kenya in 2013; and in the Arctic, including Svalbard and the Faeroes plus many airplanes aloft, in 2015. In the coming triennium, there will be total solar eclipses in Indonesia and the Pacific in 2016 and then, on 21 August 2017, a total solar eclipse that will sweep across the Continental United States from northwest to southeast. Mapping websites, all linked to http://eclipses.info, include Fred Espenak's http://EclipseWise.com; Michael Zeiler's http://GreatAmericanEclipse.com and http://eclipse-maps.com; Xavier Jubier's http://xjubier.free.fr; and (with weather and cloudiness analysis) Jay Anderson's http://eclipser.ca. Members of the Working Group, chaired by Jay Pasachoff (U.S.), include Iraida Kim (Russia), Kiroki Kurokawa (Japan), Jagdev Singh (India), Vojtech Rusin (Slovakia), Zhongquan Qu (China), Fred Espenak (U.S.), Jay Anderson (Canada), Glenn Schneider (U.S.), Michael Gill (U.K.), Xavier Jubier (France), Michael Zeiler (U.S.), and Bill Kramer (U.S.).

  5. Monitoring HD 148703 during upcoming eclipses

    NASA Astrophysics Data System (ADS)

    Waagen, Elizabeth O.

    2017-06-01

    Dr. Milena Ratajczak (University of Wrocław) has requested AAVSO observers' assistance in monitoring the very bright (V = 4.23) and very unusual eclipsing binary HD 148703 (HR 6143, N Sco) during its infrequent primary and secondary eclipses scheduled for 2017 June 11 and June 14, respectively. Dr. Ratajczak writes: "[HD 148703] N Sco is a B-type detached eclipsing binary, which turned out to be an exceptionally interesting object to study when we realised its orbital period is 223 days and time between eclipses is only 3.5 days. Such configuration makes it an extremely eccentric system, probably the most eccentric from any objects of that class ever studied...Since the object is very bright, it's difficult to use professional photometric telescopes due to saturation issues. That is why we kindly invite amateur astronomers to join the campaign. Data taken during times of eclipses (photometry) and time between eclipses (radial velocities from spectroscopy) which occur next week are crucial to cover in order to determine orbital and stellar parameters of system's components. Data taken over that time will be of very high value for us." The next primary eclipse time of minimum is on 2017 June 11 (UT 00:41:45), and the secondary on June 14 (UT 09:17:34). Each eclipse lasts about 20 hours. The amplitude of the primary eclipse is 0.15 magnitude, and the secondary 0.35 mag. PEP V and DSLR V photometry is requested. (CCD V is welcome if saturation can be avoided.) Beginning immediately, one to a few snapshots each night are requested to establish an out-of-eclipse baseline for each observer; they should continue for a few nights after the secondary eclipse has occurred.Time series photometry is requested beginning 12 hours before each time of minimum and continuing until 12 hours after. Precision to 0.01 mag or better per single observation is needed. Exposures should be as long as possible without saturating; don't make very short exposures simply for the purpose of

  6. Preparing for and Observing the 2017 Total Solar Eclipse

    NASA Astrophysics Data System (ADS)

    Pasachoff, J.

    2015-11-01

    I discuss ongoing plans and discussions for EPO and scientific observing of the 21 August 2017 total solar eclipse. I discuss aspects of EPO based on my experiences at the 60 solar eclipses I have seen. I share cloud statistics along the eclipse path compiled by Jay Anderson, the foremost eclipse meteorologist. I show some sample observations of composite imagery, of spectra, and of terrestrial temperature changes based on observations of recent eclipses, including 2012 from Australia and 2013 from Gabon. Links to various mapping sites of totality, partial phases, and other eclipse-related information, including that provided by Michael Zeiler, Fred Espenak (retired from NASA) and Xavier Jubier can be found on the website I run for the International Astronomical Union's Working Group on Eclipses at http://www.eclipses.info.

  7. Dysfunctional C8 beta chain in patients with C8 deficiency.

    PubMed

    Tschopp, J; Penea, F; Schifferli, J; Späth, P

    1986-12-01

    Two sera from unrelated individuals, each lacking C8 activity, were examined by Western blot analysis. Using antisera raised against whole C8, the two sera are shown to lack the C8 beta chain, indicating a C8 beta deficiency, which is frequently observed in cases of dysfunctional C8. In contrast, by means of a specific anti-C8-beta antiserum, a C8 beta-like polypeptide chain of apparently identical molecular weight compared to normal C8 beta was detected. Digestion of normal and dysfunctional C8 beta with Staphylococcus aureus V8 protease revealed distinct differences in the enzymatic digestion pattern. We conclude that the dysfunction in the C8 protein in these two patients resides in the dysfunctional C8 beta chain, and that this form of C8 deficiency is distinct from C8 deficiencies previously reported, in which one or both C8 subunits are lacking.

  8. Total Solar Eclipse of 2008 August 01

    NASA Technical Reports Server (NTRS)

    Espenak, F.; Anderson, J.

    2007-01-01

    On 2008 August 01, a total eclipse of the Sun is visible from within a narrow corridor that traverses half the Earth. The path of the Moon's umbral shadow begins in northern Canada and extends across Greenland, the Arctic, central Russia, Mongolia, and China. A partial eclipse is seen within the much broader path of the Moon's penumbral shadow, which includes northeastern North America, most of Europe and Asia. Detailed predictions for this event are presented and include besselian elements, geographic coordinates of the path of totality, physical ephemeris of the umbra, topocentric limb profile corrections, local circumstances for 308 cities, maps of the eclipse path, weather prospects, the lunar limb profile and the sky during totality. Information on safe eclipse viewing and eclipse photography is included.

  9. Boise State's Idaho Eclipse Outreach Program

    NASA Astrophysics Data System (ADS)

    Davis, Karan; Jackson, Brian

    2017-10-01

    The 2017 total solar eclipse is an unprecedented opportunity for astronomical education throughout the continental United States. With the path of totality passing through 14 states, from Oregon to South Carolina, the United States is expecting visitors from all around the world. Due to the likelihood of clear skies, Idaho was a popular destination for eclipse-chasers. In spite of considerable enthusiasm and interest by the general population, the resources for STEM outreach in the rural Pacific Northwest are very limited. In order to help prepare Idaho for the eclipse, we put together a crowdfunding campaign through the university and raised over $10,000. Donors received eclipse shades as well as information about the eclipse specific to Idaho. Idaho expects 500,000 visitors, which could present a problem for the many small, rural towns scattered across the path of totality. In order to help prepare and equip the public for the solar eclipse, we conducted a series of site visits to towns in and near the path of totality throughout Idaho. To maximize the impact of this effort, the program included several partnerships with local educational and community organizations and a focus on the sizable refugee and low-income populations in Idaho, with considerable attendance at most events.

  10. Ep7_Total Eclipse over America

    NASA Image and Video Library

    2017-08-18

    many parts of the world, the bang on pots and pans. >> Yeah, they don t know the-- like, the science behind this total solar eclipse, so they re-- >> that s right. >> Yeah, right, go ahead. >> I think part of this tradition is passed on. >> Yeah, tradition, yeah. >> Well, unfortunately, this poor chinese astronomer that didn t do his job, he got executed. >> Oh. >> So, fortunately, we don t hold our scientists to this same level there. >> I m very thankful of that. >> Yes. >> I m sure we are. Yeah. >> But, lots of ancient people were scared of eclipses because they thought they-- i mean, it s a very amazing thing to happen in the sky and they were worried about it. It s warning of some tragedy. >> Mm-hmm. >> So early scientists in multiple cultures-- the mayans, the babylonians, the chinese-- studied eclipses and tried to understand and predict when they would occur. It turned out there was a greek by the name of thales who predicted an eclipse in 585 b.c. And this was recorded and the greek historian, herodotus, there was a big battle going on between two countries. There were the medes and the lydians, in what s now turkey. >> Hmm. >> And there was a war going on and they had lined up for battle. And they were about to do battle and suddenly there was a solar eclipse. >> Oh. >> Os, needless to say, the two generals met in the middle of the field and said, maybe we ought not to fight today. And so they drew up a peace treaty and those two countries never fought again. So just a-- >> all right. So an example of solar eclipse saving lives. >> That s right. Indeed, indeed. And so, but what happened was, a lot of these-- as people began to learn to write things down-- the babylonians on clay tablets, and the chinese court records, and the greek historians-- people began to pull together this information to understand how to predict eclipses and understand how the cycles occur. And that helped the-- that sort of spawned the whole science of astronomy. How do you-- how d

  11. Eclipse cooling of selected lunar features

    NASA Technical Reports Server (NTRS)

    Shorthill, R. W.; Saari, J. M.; Baird, F. E.; Lecompte, J. R.

    1970-01-01

    Thermal measurements were made in the 10 to 12 micron band of the lunar surface during the total eclipse of December19, 1964. A normalized differential thermal contour map is included, showing the location of the thermal anomalies or hot spots on the disk and the eclipse cooling curves of 400 sites, of which more than 300 were hot spots. The eclipse cooling data is compared to a particulate thermophysical model of the soil.

  12. Solar Eclipse 2017

    NASA Image and Video Library

    2017-08-21

    From the Kennedy Space Center Visitor Complex, guests joined Americans from coast to coast following the solar eclipse. Speaking at the event was astronaut John-David Bartoe. Although a partial eclipse on Florida's Space Coast, young and old alike found many ways to watch the rare astronomical event. As the Moon passed between Earth and the midafternoon Sun, a shadow moved across the landscape. The 70-mile-wide totality path, or "umbral cone" -- where the entire Sun will vanish behind the Moon -- stretched across 14 states, from Oregon to South Carolina.

  13. Solar Eclipse 2017

    NASA Image and Video Library

    2017-08-21

    From the Kennedy Space Center Visitor Complex, guests joined Americans from coast to coast following the solar eclipse. Guest speakers were, astronaut John-David Bartoe, left, and communicator Jeff Lucas. Although a partial eclipse on Florida's Space Coast, young and old alike found many ways to watch the rare astronomical event. As the Moon passed between Earth and the midafternoon Sun, a shadow moved across the landscape. The 70-mile-wide totality path, or "umbral cone" -- where the entire Sun will vanish behind the Moon -- stretched across 14 states, from Oregon to South Carolina.

  14. The Great American Eclipse: Lessons Learned from Public Education

    NASA Astrophysics Data System (ADS)

    Edson, Shauna Elizabeth; Phoebe Waterman Haas Public Observatory

    2018-01-01

    The total solar eclipse of 2017 was a high-profile opportunity for nationwide public education. Astronomy experts suddenly became vital sources of information for a lay population whose interest in the eclipse greatly surpassed expectations. At the National Air and Space Museum, we leveraged our relatively accessible location and particularly diverse audience to help thousands of people, from novices to enthusiasts, prepare to view the eclipse safely. The goal was to empower all people so they could experience this unique astronomical event, understand what was happening, and observe the Sun safely. Over the course of two years spent talking with the public about the eclipse, we encountered common misconceptions, worries about safety or liability, and people experiencing confusion or information overload. We developed guidelines for handling these challenges, from correcting misinformation to managing the sudden spike in demand for glasses just before August 21.In particular, we helped people understand the following essential points:- The total phase of the eclipse is only visible from a limited path.- The partial eclipse is visible from a large area outside the path of totality.- The eclipse takes up to three hours from start to finish, providing ample time for viewing.- The Sun can be observed safely using several methods, including but not limited to eclipse glasses.- The eclipse happens because the Moon’s orbit is taking it directly between the Sun and the Earth.- Eclipses do not happen every month because the Moon’s orbit is tilted with respect to the Earth's orbital plane.- Students in schools can safely view the eclipse, with proper protection and supervision, to prevent eye damage and minimize liability.Public education about the eclipse appears to have been successful, as evidenced by the large number of people who saw their first total solar eclipse and the absence of reported eye damage cases. Amidst the excitement, photographs, and stories that

  15. Epsilon Aurigae Eclipse 2009 - Ingress

    NASA Astrophysics Data System (ADS)

    Hopkins, Jeffrey L.; Stencel, Robert E.; Leadbeater, Robin; Beckmann, Paul J.; Buil, Christian; Collins, Donald; Colombo, Tiziano; Garrel, Thierry; Gorodenski, Stanley; Gudmundsson, Snaevarr; Karlsson, Mukund Kurtadikar; Lindberg, Hans-Goran; Loughney, Des; Mauclaire, Benji; McCandless, Brian E.; Melillo, Frank J.; Miles, Richard; Pearson, Robert T.; Samolyk, Gerard; Schanne, Lothar; Strikis, Iakovos Marios; Teyssier, François; Thizy, Olivier

    The mysterious star system epsilon Aurigae undergoes an eclipse every 27.1 years that lasts nearly two years. The most recent eclipse started during the late summer of 2009. An international campaign for observing this eclipse was created in 2006, with a web site for information and, to-date, 17 periodic newsletters for details, as well as a Yahoo forum List for immediate announcements and comments. Photometric data in the UBVRIJH bands have been submitted. Ingress occurred with first contact in the V band estimated at the second week of 2009 August and second contact estimated at 2010 mid-January. Spectroscopic data were also obtained during ingress. Spectroscopic data have been provided in the potassium I region, hydrogen alpha and beta regions and sodium D line region of the star system's spectrum. In this paper we describe details of observations and preliminary analysis during ingress and second contact. We introduce the observers and discuss plans for observing throughout totality and the end of the eclipse in 2011.

  16. Solar corona during the 1994 and 1999 eclipses

    NASA Astrophysics Data System (ADS)

    Badalyan, O. G.; Sýkora, J.

    2008-06-01

    The lower and middle layers of the corona are studied analyzing the ground-based observations carried out during the November 3, 1994 and August 11, 1999 total solar eclipses. While the 1994 eclipse took place nearby the solar activity minimum, the 1999 eclipse occurred closer to the solar cycle maximum. Structures, isolines of brightness and polarization, and topology of the magnetic field lines of force (calculated under a potential approximation) of these two coronae are mutually compared. It is confirmed that the brightness distribution in the corona corresponds to the hydrostatic distribution of density at the distances 1.2-1.8R⊙. Temperature 1.4 MK and density n0 = 3.3 × 108cm-3 are found for the equatorial coronal regions of the 1999 corona. Physical conditions in the polar coronal regions are investigated analyzing the brightness and polarization of the 1994 eclipse. We have found that the degree of polarization in polar plumes is about 10% higher than that in the inter-plumes space. Consideration of the brightness in plumes and in the adjacent background space allowed us to conclude that the temperatures there are close to 1 MK. The density in the individual plumes is near n0 = 2.7 × 108cm-3, while it decreases to about n0 = 2.0 × 108cm-3 in the inter-plumes space. It is pointed out that the simultaneous interpretation of the measured brightness and polarization struggles with some difficulties.

  17. Notable Images of the 2017 Total Solar Eclipse

    NASA Astrophysics Data System (ADS)

    Wilson, Teresa; Dahiwale, Aishwarya; Nemiroff, Robert; Bonnell, Jerry

    2018-01-01

    The "Great American Eclipse" – the total solar eclipse visible across the USA on 21 August 2017 – resulted in some notable eclipse images and videos high in educational and scientific value. Some of the images that were selected to appear on the Astronomy Picture of the Day (APOD) website are shown in high resolution accompanied by educational descriptions. The questions of whether this eclipse was the most viewed and the most photographed event of any type in human history will be discussed. People are invited to come by and share their own eclipse images and stories.

  18. McDonald 2.1-m and CRTS Photometry of Eclipsing Polars

    NASA Astrophysics Data System (ADS)

    Wells, Natalie; Mason, Paul

    2018-01-01

    We present broadband optical photometry of five polars made using the 2.1-m telescope of McDonald Observatory. Four of the polars are eclipsing (EP Dra, FL Cet, V2301 Oph, and a Catalina Sky Survey (CSS) polar candidate). In addition, a pre-polar (MQ Dra) was observed. Typical integration times were 1-3 seconds with no dead time. At this time resolution, eclipse structure can be seen in both one- and two-pole accretors. McDonald 2.1-m data over several years is phased together with CSS photometry covering up to 7 years, in search of indications of period variation. Combining the high-resolution, high-speed photometry obtained using the ProEm camera on the McDonald 2.1-m with the sparse, but high-quality multi-year baseline photometry of the CSS places strong constraints on the time variability of the eclipse periods in these binary systems. In most cases, eclipse variations do not perfectly fit a linear ephemeris. We investigate the source of variations using standard O-C diagram techniques and period search algorithms.

  19. The (Almost) Unseen Total Eclipse of 1831

    NASA Astrophysics Data System (ADS)

    Bartky, Ian R.

    2008-03-01

    The total eclipse of August 1831 began at sunrise in Australia, swept across the western South Pacific Ocean, and ended at sunset in the central South Pacific. As a result of the eclipse's path over mostly uninhabited ocean, the region's sparse European (British) population, and near-useless local predictions of the event at Hobart and Sydney in almanacs sold to the general public, almost no one witnessed its passage. In an attempt to document the eclipse, journals of naive observers - those having no access to a prediction - were examined. Thus far, the sole record is in the Pitcairn Island Register Book. Considering the Pitcairners' extreme isolation and the rather modest partial eclipse that occurred there, the entry is a surprising one; however, it can be explained in terms of events associated with their initial removal to Tahiti in March 1831 followed by their return home in June. Further, an authoritative means to identify any issues associated with eclipse predictions compiled for private-sector almanacs came in 1833 when sweeping changes in the British Nautical Almanac's section on eclipses were instituted.

  20. Report about the Solar Eclipse on August 11, 1999

    NASA Astrophysics Data System (ADS)

    1999-08-01

    This webpage provides information about the total eclipse on Wednesday, August 11, 1999, as it was seen by ESO staff, mostly at or near the ESO Headquarters in Garching (Bavaria, Germany). The zone of totality was about 108 km wide and the ESO HQ were located only 8 km south of the line of maximum totality. The duration of the phase of totality was about 2 min 17 sec. The weather was quite troublesome in this geographical area. Heavy clouds moved across the sky during the entire event, but there were also some holes in between. Consequently, sites that were only a few kilometres from each other had very different viewing conditions. Some photos and spectra of the eclipsed Sun are displayed below, with short texts about the circumstances under which they were made. Please note that reproduction of pictures on this webpage is only permitted, if the author is mentioned as source. Information made available before the eclipse is available here. Eclipse Impressions at the ESO HQ Photo by Eddy Pomaroli Preparing for the Eclipse Photo: Eddy Pomaroli [JEG: 400 x 239 pix - 116k] [JPEG: 800 x 477 pix - 481k] [JPEG: 3000 x 1789 pix - 3.9M] Photo by Eddy Pomaroli During the 1st Partial Phase Photo: Eddy Pomaroli [JPEG: 400 x 275 pix - 135k] [JPEG: 800 x 549 pix - 434k] [JPEG: 2908 x 1997 pix - 5.9M] Photo by Hamid Mehrgan Heavy Clouds Above Digital Photo: Hamid Mehrgan [JPEG: 400 x 320 pix - 140k] [JPEG: 800 x 640 pix - 540k] [JPEG: 1280 x 1024 pix - 631k] Photo by Olaf Iwert Totality Approaching Digital Photo: Olaf Iwert [JPEG: 400 x 320 pix - 149k] [JPEG: 800 x 640 pix - 380k] [JPEG: 1280 x 1024 pix - 536k] Photo by Olaf Iwert Beginning of Totality Digital Photo: Olaf Iwert [JPEG: 400 x 236 pix - 86k] [JPEG: 800 x 471 pix - 184k] [JPEG: 1280 x 753 pix - 217k] Photo by Olaf Iwert A Happy Eclipse Watcher Digital Photo: Olaf Iwert [JPEG: 400 x 311 pix - 144k] [JPEG: 800 x 622 pix - 333k] [JPEG: 1280 x 995 pix - 644k] ESO HQ Eclipse Video Clip [MPEG-version] ESO HQ Eclipse Video

  1. Annular and Total Solar Eclipses of 2003

    NASA Technical Reports Server (NTRS)

    Espenak, Fred; Anderson, Jay

    2002-01-01

    On Saturday, 2003 May 31, an annular eclipse of the Sun will be visible from a broad corridor that traverses the North Atlantic. The path of the Moon's antumbral shadow begins in northern Scotland, crosses Iceland and central Greenland, and ends at sunrise in Baffin Bay (Canada). A partial eclipse will be seen within the much broader path of the Moon's penumbral shadow, which includes most of Europe, the Middle East, central and northern Asia, and northwestern North America. The trajectory of the Moon's shadow is quite unusual during this event. The shadow axis passes to the far north where it barely grazes Earth's surface. In fact, the northern edge of the antumbra actually misses Earth so that one path limit is defined by the day/night terminator rather than by the shadow's upper edge. As a result, the track of annularity has a peculiar "D" shape that is nearly 1200 kilometers wide. Since the eclipse occurs just three weeks prior to the northern summer solstice, Earth's northern axis is pointed sunwards by 22.8 deg. As seen from the Sun, the antumbral shadow actually passes between the North Pole and the terminator. As a consequence of this extraordinary geometry, the path of annularity runs from east to west rather than the more typical west to east. The event transpires near the Moon's ascending node in Taurus five degrees north of Aldebaran. Since apogee occurs three days earlier (May 28 at 13 UT), the Moon's apparent diameter (29.6 arc-minutes) is still too small to completely cover the Sun (31.6 arc-minutes) resulting in an annular eclipse.

  2. Bringing the Great American Solar Eclipse to West Virginia

    NASA Astrophysics Data System (ADS)

    Keesee, A. M.; Williamson, K.; Robertson-Honecker, J.

    2017-12-01

    West Virginia experienced up to 90% coverage during the Great American Solar Eclipse on August 21st. To reach the greatest number of West Virginians, we targeted educators and the 4-H program to provide those community leaders with the tools to help students learn about and safely view the eclipse. We developed a website that consolodated relevant eclipse activities, fact sheets, and outreach videos to train educators and others in the public about the science of the eclipse and how to view a partial eclipse safely. The 4-H Summer Experiement used at all 4-H summer camps and events was designed to focus on the eclipse. We distributed over 20,000 custom designed eclipse glasses. These were distributed to teachers through an online request system and to 4-H members involved in summer activities. We hosted a pre-eclipse event on the campus of West Virginia University for the public to learn about the science of the eclipse, relevant research being conducted at the university, and provide tips for safe viewing. Student volunteers were available on campus during the day of the eclipse to hand out glasses and answer questions. We will present the results of our outreach and events as well as lessons learned for the 2024 eclipse. Support for this project was provided by the WVU Department of Physics and Astronomy, WVU Extension, the WV Space Grant Consortium, a WVU internal grant, the Green Bank Observatory, and individual supporters of a crowdfunding campaign.

  3. Double cyclic variations in orbital period of the eclipsing cataclysmic variable EX Dra

    NASA Astrophysics Data System (ADS)

    Han, Zhong-tao; Qian, Sheng-bang; Voloshina, Irina; Zhu, Li-Ying

    2017-06-01

    EX Dra is a long-period eclipsing dwarf nova with ˜2-3 mag amplitude outbursts. This star has been monitored photometrically from November, 2009 to March, 2016 and 29 new mid-eclipse times were obtained. By using new data together with the published data, the best fit to the O-C curve indicate that the orbital period of EX Dra have an upward parabolic change while undergoing double-cyclic variations with the periods of 21.4 and 3.99 years, respectively. The upward parabolic change reveals a long-term increase at a rate of \\dot{P}= {+7.46}×10^{-11} s s^{-1}. The evolutionary theory of cataclysmic variables (CVs) predicts that, as a CV evolves, the orbital period should be decreasing rather than increasing. Secular increase can be explained as the mass transfer between the secondary and primary or may be just an observed part of a longer cyclic change. Most plausible explanation for the double-cyclic variations is a pair of light travel-time effect via the presence of two companions. Their masses are determined to be MAsin i'A=29.3(±0.6) M_{Jup} and MBsin i'B=50.8(±0.2) M_{Jup}. When the two companions are coplanar to the orbital plane of the central eclipsing pair, their masses would match to brown dwarfs.

  4. 1SWASP J200503.05-343726.5: A high mass ratio eclipsing binary near the period limit

    NASA Astrophysics Data System (ADS)

    Bin, Zhang; Shengbang, Qian; Zejda, Miloslav; Liying, Zhu; Nianping, Liu

    2017-07-01

    First CCD photometric light curves of the eclipsing binary system 1SWASP J200503.05-343726.5 are presented. Our complete light curves in V, R and I bands using the Bessell filter show an out-of-eclipsing distortion, which means that the components of the system may be active. The preliminary photometric solutions with a cool star-spot are derived by using the 2013 version of the Wilson-Devinney (W-D) code. The photometric solutions suggest that 1SWASP J200503.05-343726.5 is a shallow-contact eclipsing binary(f = 9.0 %) with a mass ratio of q = 1.0705 , which is very high for late-type binary systems near the period limit. The primary component is about 230 K hotter than the secondary component. Based on our new CCD eclipse times, the orbital period change was analyzed. According to O - C diagram, the orbital period of the 1SWASP J200503.05-343726.5 shows an increase at a rate of P˙ = + 5.43 ×10-8 days year-1. The period increase may be caused by mass transfer from the less massive component to the more massive one. This shallow-contact system may be formed from a detached short-period binary via orbital shrinkage because of dynamical interactions with a third component or by magnetic braking.

  5. Total Solar Eclipse of 2006 March 29

    NASA Technical Reports Server (NTRS)

    Espenak, F.; Anderson, J.

    2004-01-01

    On 2006 March 29, a total eclipse of the Sun will be visible from within a narrow corridor which traverses half the Earth. The path of the Moon's umbral shadow begins in Brazil and extends across the Atlantic, northern Africa, and central Asia where it ends at sunset in western Mongolia. A partial eclipse will be seen within the much broader path of the Moon's penumbral shadow, which includes the northern two thirds of Africa, Europe, and central Asia.Detailed predictions for this event are presented and include besselian elements, geographic coordinates of the path of totality, physical ephemeris of the umbra, topocentric limb profile corrections, local circumstances for approximately 350 cities, maps of the eclipse path, weather prospects, the lunar limb profile, and the sky during totality. Information on safe eclipse viewing and eclipse photography is included.

  6. Strategies for the public communication of eclipses

    NASA Astrophysics Data System (ADS)

    Bretones, P. S.

    2015-03-01

    Eclipses are among the celestial events that draw the attention of the public. This paper discusses strategies for using eclipses as public communication opportunities in the media. It discusses the impact of articles written by the author and analysis of published material for 25 observed eclipses over the last 30 years by mass media in the state of São Paulo, Brazil. On each occasion, a standard article was posted on the Internet and sent to newspapers, radio and TV with information, such as: date, time and local circumstances; type of the eclipse; area of visibility; explanation; diagram of the phenomenon, and the Moon's path through Earth's shadow; eclipses in history; techniques of observation; getting photographs; place and event for public observation. Over the years, direct contact was maintained with the media and jounralists by the press offices of the institutions.

  7. Total Solar Eclipse of 2002 December 04

    NASA Technical Reports Server (NTRS)

    Espenak, Fred; Anderson, Jay

    2001-01-01

    On 2002 December 04, a total eclipse of the Sun will be visible from within a narrow corridor which traverses the Southern Hemisphere. The path of the Moon's umbral shadow begins in the South Atlantic, crosses southern Africa and the Indian Ocean, and ends at sunset in southern Australia. A partial eclipse will be seen within the much broader path of the Moon's penumbral shadow, which includes the southern two thirds of Africa, Antarctica, Indian Ocean and Australia. Detailed predictions for this event are presented and include besselian elements, geographic coordinates of the path of totality, physical ephemeris of the umbra, topocentric limb profile corrections, local circumstances for approximately 400 cities, maps of the eclipse path, weather prospects, the lunar limb profile and the sky during totality. Information on safe eclipse viewing and eclipse photography is included.

  8. EE Cep observations requested for upcoming eclipse

    NASA Astrophysics Data System (ADS)

    Waagen, Elizabeth O.

    2014-07-01

    The AAVSO requests observations for the upcoming eclipse of EE Cephei, a long-period eclipsing variable. EE Cep has a period of 2,050 days, and shows strong variations in the eclipse light curve from one event to the next. Observations are needed to study the morphology of the upcoming eclipse, which will be used to better understand the shape of the eclipsing disk and how it precesses. Mid-eclipse is predicted to be August 23, 2014, but the early stages of the eclipse may begin as much as a month earlier. EE Cep is being observed by a number of amateur and professional astronomers using multiple telescopes at multiple wavelengths. Among these is a collaboration (see https://sites.google.com/site/eecep2014campaign/) headed by Cezary Galan at the Nicolaus Copernicus Astronomical Center in Poland; several individual AAVSO observers are already participating in this effort. The AAVSO is not currently a partner in that campaign, but all data submitted to the AAVSO will be publicly available. The AAVSO strongly encourages observers to begin following this star now, and to continue observations into October 2014 at least. Finder charts with sequence may be created using the AAVSO Variable Star Plotter (http://www.aavso.org/vsp). Observations should be submitted to the AAVSO International Database. See full Alert Notice for more details and observations.

  9. Comparisons of Measurements and Modeling of Solar Eclipse Effects on VLF Transmissions

    NASA Astrophysics Data System (ADS)

    Eccles, J. V.; Rice, D. D.; Sojka, J. J.; Marshall, R. A.; Drob, D. P.; Decena, J. C.

    2017-12-01

    The solar eclipse of 2017 August 21 provides an excellent opportunity to examine Very Low Frequency (VLF) radio signal propagation through the path of the solar eclipse between Navy VLF transmitters and several VLF receivers. The VLF transmitters available for this study radio signal propagation study are NLK in Jim Creek, Washington (24.8 kHz, 192 kW, 48.20N, 121.90W), NML in LaMour, North Dakota (25.2 kHz, 500 kW 46.37N, 93.34W), and NAA in Cutler, Maine (24.0 kHz, 1000 kW, 44.65N, 67.29W). These VLF transmitters provide propagation paths to three VLF receivers at Utah State University (41.75N, 111.76W), Bear Lake Observatory (41.95N, 111.39W), Salt Lake City (40.76N, 111.89W) and one receiver in Boulder, Colorado (40.02N, 105.27W). The solar eclipse shadow will cross all propagations paths during the day and will modify the D region electron density within the solar shadow. The week prior to the solar eclipse will be used to generate a diurnal baseline of VLF single strength for each transmitter-receiver pair. These will be compared to the day of the solar eclipse to identify VLF propagation differences through the solar eclipse shawdow. Additionally, the electron density effects of the week prior and of the solar eclipse day will be modeled using the Data-Driven D Region (DDDR) model [Eccles et al., 2005] with a detailed eclipse solar flux mask. The Long-Wave Propagation Code and the HASEL RF ray-tracing code will be used to generate VLF signal strength for each measured propagation path through the days prior and the solar eclipse day. Model-measurement comparisons will be presented and the D region electron density effects of the solar eclipse will be examined. The DDDR is a time-dependent D region model, which makes it very suitable for the solar eclipse effects on the electron density for the altitude range of 36 to 130 km. Eccles J. V., R. D. Hunsucker, D. Rice, J. J. Sojka (2005), Space weather effects on midlatitude HF propagation paths: Observations and

  10. Educating the Public about the 2017 Total Solar Eclipse

    NASA Astrophysics Data System (ADS)

    Pasachoff, Jay M.

    2017-01-01

    On behalf of the International Astronomical Union's Working Group on Solar Eclipses, I have long worked to bring knowledge about eclipses and how to observe the safely to the people of the various countries from which partial, annular, or total solar eclipses are visible. In 2017, we have first a chance to educate the people of South America on the occasion of the February 26 annular eclipse through southern Chile and Argentina that is partial throughout almost the entire continent (and an eclipse workshop will be held February 22-24 in Esquel, Argentina: http://sion.frm.utn.edu.ar/WDEAII) and then a chance to educate the 300 million people of the United States and others in adjacent countries as far south as northern South America about the glories of totality and how to observe partial phases. Our website, a compendium of links to information about maps, safe observing, science, and more is at http://eclipses.info. We link to important mapping sites at EclipseWise.com, GreatAmericanEclipse.com, and http://xjubier.free.fr/en/site_pages/solar_eclipses/xSE_GoogleMap3.php?Ecl=+20170821&Acc=2&Umb=1&Lmt=1&Mag=1&Max=1, and information about cloudiness statistics at http://eclipsophile.com, as well as simulation sites at https://svs.gsfc.nasa.gov/cgi-bin/details.cgi?aid=4314 and http://eyes.jpl.nasa.gov. The American Astronomical Society's task force on the 2017 eclipse has a website at http://eclipse.aas.org. We are working to disseminate accurate information about how and why to observe the total solar eclipse, trying among other things to head off common misinformation about the hazards of looking at the sun at eclipses or otherwise. About 12 million Americans live within the 70-mile-wide band of totality, and we encourage others to travel into it, trying to make clear the difference between even a 99% partial eclipse and a total eclipse, with its glorious Baily's beads, diamond rings, and totality that on this occasion lasts between 2 minutes and 2 minutes 40 seconds

  11. 2017 Solar Eclipse Event

    NASA Image and Video Library

    2017-06-11

    Krisdon Manecke and Danielle Burleson of the Office of the Chief Information Officer (OCIO) view the August 21, 2017 solar eclipse at the Marshall Space Flight Center’s viewing opportunity at the activities building. The Huntsville area experienced 97 percent occultation, nearly a complete blocking out of the sun by the orbit of Earth's moon. The next opportunity to view a solar eclipse in the eastern and central United States will occur in April 2024.

  12. 2017 Solar Eclipse Event

    NASA Image and Video Library

    2017-06-11

    Judy Darwin of the Marshall Space Flight Center’s Office of the Chief Information Officer (CIO) views the August 21, 2017 solar eclipse through the telescope set up for Marshall employees. The Huntsville area experienced 97 percent occultation, nearly a complete blocking out of the sun by the orbit of Earth's moon. The next opportunity to view a solar eclipse in the eastern and central United States will occur in April 2024.

  13. The Guilford-Carleton Eclipse Expedition of 1900

    NASA Astrophysics Data System (ADS)

    English, Thomas R., III

    2006-12-01

    The solar eclipse of 1900 May 28 provided an opportunity for American astronomers to make observations from home soil, as the shadow tracked across the southeastern United States from New Orleans to Norfolk. Eclipse parties were scattered throughout the southern states, including large-scale scientific teams traveling to sites in Georgia and North Carolina. These major operations, staffed by groups from Yerkes, Princeton, USNO, and Lick, featured multiple observing programs and all the modern techniques they could manage. In addition to the major astrophysical endeavors, there were many smaller parties in the field in 1900 that resembled the more casual eclipse expeditions that were characteristic of a few decades before. In these efforts, relatively small groups of observers used modest instruments and made mostly visual observations, and the expedition was as much a social event as it was a scientific venture. One such group was the party from Carleton College and Guilford College that observed from a fruit farm in Southern Pines, NC. At the turn of the century, the Goodsell Observatory at Carleton College in Minnesota was an important regional astronomical facility that had provided weather and time data for over 20 years, and was the site of publication of Popular Astronomy, a widely circulated astronomical journal. At Guilford College, on the other hand, the astronomy course was taught by the school’s Treasurer, and there were no significant astronomical facilities. The presentation will explain how these two schools came to combine efforts to study the 1900 solar eclipse, and will summarize the events of the trip and the observations made. This research was supported in part by the Herbert C. Pollock Award of the Dudley Observatory.

  14. Development and validation of a rapid ultra-high performance liquid chromatography diode array detector method for Vitex agnus-castus.

    PubMed

    Högner, C; Sturm, S; Seger, C; Stuppner, H

    2013-05-15

    A rapid ultra-high performance liquid chromatography diode array detector (UHPLC-DAD) method was developed and validated for the simultaneous determination of all classes of non-volatile phytochemicals (iridoids, flavonoids and diterpenes) in Vitex agnus-castus (Lamiaceae) fruits, a traditional medicinal plant used against premenstrual symptoms (PMS) and other disorders. Seven marker compounds, 3,4-dihydroxybenzoic acid, p-hydroxybenzoic acid, agnuside, 5-hydroxykaempferol-3,6,7,4'-tetramethylether, 1,2-dibenzoic acid glucose, methoxy-vitexilactone, and vitetrifolin D were isolated from the methanol extract of V. agnus-castus to be used as reference substances. Chromatographic separation was performed on a Zorbax Eclipse XDB-C18 (50mm×2.1mm) UHPLC column with 1.8μm particle size, within 20min. A solvent gradient from 0.5% acetic acid to acetonitrile at a flow rate of 0.6mL/min was used as mobile phase. Analyte detection and quantification was realized at 210nm and 260nm. The UHPLC-DAD assay was validated for the quantitative analysis of agnuside, isovitexin, casticin, 5-hydroxykaempferol-3,6,7,4'-tetramethylether and vitetrifolin D. It was found to be specific, accurate, precise, and reproducible for the quantification of these compound within a concentration range of 0.7-500.0μg/mL for casticin and 5-hydroxykaempferol-3,6,7,4'-tetramethylether, 1.4-1000.0μg/mL for isovitexin and agnuside, and 12.4-1000.0μg/mL for vitetrifolin D. Intra- and inter-day variations showed relative standard deviations (RSD) of less than 3.9% and 6.4%, respectively. Tentatively assignment of 62 chromatographic features found in the UHPLC-DAD assay was carried out by coupling the UHPLC instrument to a quadrupole time-of-flight mass spectrometer via an electrospray ionization interface (ESI-QTOF-MS) operated in positive and negative ion mode. By using the established quantitative UHPLC-DAD assay to asses agnuside, isovitexin, casticin, 5-hydroxykaempferol-3,6,7,4'-tetramethylether and

  15. The orbital and superhump periods of the deeply eclipsing dwarf nova SDSS J150240.98+333423.9

    NASA Astrophysics Data System (ADS)

    Shears, J.; Campbell, T.; Foote, J.; Garrett, R.; Hager, T.; Mack Julian, W.; Kemp, J.; Masi, G.; Miller, I.; Patterson, J.; Richmond, M.; Ringwald, F.; Roberts, G.; Ruiz, J.; Sabo, R.; Stein, W.

    2011-04-01

    During 2009 July we observed the first confirmed superoutburst of the eclipsing dwarf nova SDSS J150240.98+333423.9 using CCD photometry. The outburst amplitude was at least 3.9 magnitudes and it lasted at least 16 days. Superhumps having up to 0.35 mags peak-to-peak amplitude were present during the outburst, thereby establishing it to be a member of the SU UMa family. The mean superhump period during the first 4 days of the outburst was Psh= 0.06028(19)d, although it increased during the outburst with dPsh/dt= +2.8(1.0)?10^-4. The orbital period was measured as Porb= 0.05890946(5)d from times of eclipses measured during outburst and quiescence. Based on the mean superhump period, the superhump period excess was e= 0.023(3). The FWHM eclipse duration declined from a maximum of 10.5 min at the peak of the outburst to 3.5 min later in the outburst. The eclipse depth increased from ~0.9 mag to 2.1 mag over the same period. Eclipses in quiescence were 2.7 min in duration and 2.8 mag deep.

  16. Campaign for a New Eclipsing Cepheid

    NASA Astrophysics Data System (ADS)

    Henden, Arne; Welch, Doug; Terrell, Dirk

    2007-06-01

    ASAS 182611+1212.6, discovered by Pojmanski et al. during the ASAS survey, independently discovered by Antipin at al. on Moscow archive plates, and found in the NSVS (Wozniak et al. 2004, AJ 127, 2436), was initially classified as a typical Type II Cepheid with a period of 4.1523 days. However, scatter in the light curve indicated possible multiperiodic behavior. After 3 years of CCD observations by Antipin, the system was seen to exhibit eclipses of period 51.38 days and amplitude about 0.3 mag (primary) and possibly about 0.2 mag (secondary). This is the first known glactic eclipsing binary Cepheid. The AAVSO is conducting a campaign to study this star via high-precision, multicolor photometry obtained over several eclipse cycles. Observers are requested to obtain multicolor photometry with a S/N=100 or better on every image. Time resolution of one hour is adequate, so cycling through the filters need not be rushed. Apply transformation coefficients when possible. For calculating ephemerides, the pulsational maximum occurred on HJD 2453196.529 with a period of 4.1523 days; the eclipse primary minimum occurred on HJD 2453571.36 with a period of 51.38 days. The next primary eclipse will occur around July 9, but these eclipses are several days wide. A finding chart may be found at http://www.aavso.org/observing/charts/vsp (enter ASAS182612 for its name, or use the coordinates) with suitable comparison stars marked. Report/upload observations to the AAVSO.

  17. Eclipse of epsilon Aurigae

    NASA Astrophysics Data System (ADS)

    Templeton, Matthew R.

    2009-07-01

    The bright, long-period, eclipsing binary star epsilon Aurigae is predicted to begin its next eclipse late July or early August of 2009. Epsilon Aurigae is now past solar conjunction and has reappeared as a morning object. All observers -- both visual and instrumental -- are encouraged to contribute observations of the eclipse during the next two years, beginning immediately for morning observers. Observations are urgently requested right now because it is less likely to be observed in the morning, and the eclipse will begin within the next month. The AAVSO is participating in a global campaign to record this eclipse as part of the International Year of Astronomy 2009 celebrations, organized by the Citizen Sky project (http://www.citizensky.org). For experienced visual observers, please observe this star on a weekly basis, using charts available via VSP from the AAVSO website. For novice visual observers, we recommend participating in this observing program by following the Citizen Sky 10-Star tutorial program, which provides a simple training experience in variable star observing. Photoelectric observers belonging to the AAVSO PEP-V program may submit data as usual via the WebObs feature of the AAVSO website Blue&Gold section. Photoelectric observers may also contribute reduced observations in all filters (including infrared J- and H-bands) directly to the AAVSO via WebObs. Observers using wide-field CCD and DSLR systems are also encouraged to participate; avoid saturating the star. For those with narrower-field systems (D < 2 degrees), we recommend taking a large number (10-100) of very short exposures and then stacking the resulting images. Observations should be submitted to the AAVSO International Database. Aaron Price is coordinating Citizen Sky for the AAVSO, and Dr. Robert Stencel and Jeffrey Hopkins are co-leading the precision photometry efforts.

  18. NASA Videofile of Solar Eclipse from Jefferson City, Missouri

    NASA Image and Video Library

    2017-08-21

    During the eclipse, 14 states across the U.S. were in the path of totality and experienced more than two minutes of darkness in the middle of the day – with a partial eclipse viewable all across North America. The broadcast – Eclipse Across America: Through the Eyes of NASA – covered locations along the path of totality, from Oregon to South Carolina including public reactions from all ages. During this event, NASA Glenn Research Center celebrates the eclipse at the capital eclipse event in Jefferson City, MO

  19. Spitzer secondary eclipses of Qatar-1b

    NASA Astrophysics Data System (ADS)

    Garhart, Emily; Deming, Drake; Mandell, Avi; Knutson, Heather; Fortney, Jonathan J.

    2018-02-01

    Aims: Previous secondary eclipse observations of the hot Jupiter Qatar-1b in the Ks band suggest that it may have an unusually high day side temperature, indicative of minimal heat redistribution. There have also been indications that the orbit may be slightly eccentric, possibly forced by another planet in the system. We investigate the day side temperature and orbital eccentricity using secondary eclipse observations with Spitzer. Methods: We observed the secondary eclipse with Spitzer/IRAC in subarray mode, in both 3.6 and 4.5 μm wavelengths. We used pixel-level decorrelation to correct for Spitzer's intra-pixel sensitivity variations and thereby obtain accurate eclipse depths and central phases. Results: Our 3.6 μm eclipse depth is 0.149 ± 0.051% and the 4.5 μm depth is 0.273 ± 0.049%. Fitting a blackbody planet to our data and two recent Ks band eclipse depths indicates a brightness temperature of 1506 ± 71 K. Comparison to model atmospheres for the planet indicates that its degree of longitudinal heat redistribution is intermediate between fully uniform and day-side only. The day side temperature of the planet is unlikely to be as high (1885 K) as indicated by the ground-based eclipses in the Ks band, unless the planet's emergent spectrum deviates strongly from model atmosphere predictions. The average central phase for our Spitzer eclipses is 0.4984 ± 0.0017, yielding e cos ω = -0.0028 ± 0.0027. Our results are consistent with a circular orbit, and we constrain e cos ω much more strongly than has been possible with previous observations. Tables of the lightcurve data are only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (http://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/610/A55

  20. NEWS: Eye safety and the solar eclipse

    NASA Astrophysics Data System (ADS)

    LeConte, David

    1999-05-01

    Total eclipses of the Sun are amongst nature's most magnificent spectacles, and offer the opportunity for an exceptional educational experience. Many people never see one in their lifetime, but it has been estimated that this August's eclipse will be seen by more people than any other. It would be a sadly lost opportunity if they were denied the experience because they fear a danger that is easily avoided. The dangers of eye damage are real and precautions need to be taken. Staring at the bright solar photosphere can cause temporary or permanent retinal damage. Since the retina has no pain receptors the observer can be unaware that the eye is being `cooked', and the damage may only become apparent several hours later. However, when the photosphere is completely blocked by the Moon during the brief period of totality (two minutes or less), it is quite safe to look directly. In fact, you will not otherwise see anything at all. It is a complex message to get across to the public, and especially to children, that protection is required during the partial phases but not during totality, and that those outside the path of totality require protection for the whole eclipse. The National Eclipse Group was established by PPARC in 1997 to coordinate educational activities, issue public information and give authoritative advice for the 1999 eclipse. It has published a Solar Eclipse Safety Code, which is available on the national eclipse web site (mentioned above). It advises that the safest way to view the Sun is indirectly, by projecting an image of the Sun with a `pinhole', mirror, binoculars or telescope. Most people, however, will wish to observe the eclipse directly. Sunglasses, photographic film, crossed polarizers, smoked glass and similar filters must not be used. The Safety Code states that the Sun may be viewed directly only through special filters made specifically for solar viewing. Such eclipse viewers are typically made of aluminized polyester film (often

  1. Astronomy in Denver: Centenary of the 1918 total solar eclipse across Denver

    NASA Astrophysics Data System (ADS)

    Stencel, Robert E.

    2018-06-01

    Totality during the 2017 August 21 solar eclipse (Saros 145) traveled along a path across the United States similar to that which occurred for the eclipse on 1918 June 8 (Saros 126), but with a less west-northerly track. This placed Denver and its then new Chamberlin Observatory in the path of totality. Denver University astronomy Professor Herbert Howe offered use of the Chamberlin Observatory 20-inch f/15 refractor, with its Clark doublet lens and Saegmueller mounting, in service of eclipse-related research. In preparation for the eclipse, Professor Howe and assistants had spent the last three months of 1917, refurbishing mechanical aspects of the telescope. Edwin Frost, then Director of Yerkes Observatory expressed interest and made a reconnaissance visit to the area in September 1917, reporting results in the Feb. 1918 issue of Popular Astronomy ( http://adsabs.harvard.edu/abs/1918PA.....26R.103F ). Frank Schlesinger, then director of Allegheny Observatory, asked if he might attach a special camera for star photography to the telescope at the eclipse, to test displacement of stars, in order to test a prediction of relativity theory. Among the additional visiting astronomical luminaries present on that June day in 1918 were Annie J. Cannon (Harvard), John Duncan (Wellesley), Herbert R. Morgan (U.S. Naval Observatory) and Robert Trumpler (Berkeley). To learn the results of all this eclipse preparedness, you will need to attend my talk in order to get “the rest of the story” or visit our twitter feed at: https://twitter.com/Chamberlin_Obs .

  2. LUMINOSITY DISCREPANCY IN THE EQUAL-MASS, PRE-MAIN-SEQUENCE ECLIPSING BINARY PAR 1802: NON-COEVALITY OR TIDAL HEATING?

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

    Gomez Maqueo Chew, Yilen; Stassun, Keivan G.; Hebb, Leslie

    Parenago 1802, a member of the {approx}1 Myr Orion Nebula Cluster, is a double-lined, detached eclipsing binary in a 4.674 day orbit, with equal-mass components (M{sub 2}/M{sub 1} = 0.985 {+-} 0.029). Here we present extensive VI{sub C} JHK{sub S} light curves (LCs) spanning {approx}15 yr, as well as a Keck/High Resolution Echelle Spectrometer (HIRES) optical spectrum. The LCs evince a third light source that is variable with a period of 0.73 days, and is also manifested in the high-resolution spectrum, strongly indicating the presence of a third star in the system, probably a rapidly rotating Classical T Tauri star.more » We incorporate this third light into our radial velocity and LC modeling of the eclipsing pair, measuring accurate masses (M{sub 1} = 0.391 {+-} 0.032 and M{sub 2} = 0.385 {+-} 0.032 M{sub Sun }), radii (R{sub 1} = 1.73 {+-} 0.02 and R{sub 2} = 1.62 {+-} 0.02 R{sub Sun }), and temperature ratio (T{sub eff,1}/T{sub eff,2} = 1.0924 {+-} 0.0017). Thus, the radii of the eclipsing stars differ by 6.9% {+-} 0.8%, the temperatures differ by 9.2% {+-} 0.2%, and consequently the luminosities differ by 62% {+-} 3%, despite having masses equal to within 3%. This could be indicative of an age difference of {approx}3 Multiplication-Sign 10{sup 5} yr between the two eclipsing stars, perhaps a vestige of the binary formation history. We find that the eclipsing pair is in an orbit that has not yet fully circularized, e = 0.0166 {+-} 0.003. In addition, we measure the rotation rate of the eclipsing stars to be 4.629 {+-} 0.006 days; they rotate slightly faster than their 4.674 day orbit. The non-zero eccentricity and super-synchronous rotation suggest that the eclipsing pair should be tidally interacting, so we calculate the tidal history of the system according to different tidal evolution theories. We find that tidal heating effects can explain the observed luminosity difference of the eclipsing pair, providing an alternative to the previously suggested age

  3. Fifty year canon of solar eclipses: 1986-2035

    NASA Technical Reports Server (NTRS)

    Espenak, Fred

    1986-01-01

    A reference of moderately detailed eclipse predictions and maps for use by the professional astronomical community is provided. The general characteristics of every solar eclipse and a detailed set of cylindrical project world maps which show the umbral paths of every solar eclipse from 1901 to 2100 are presented. The geodetic path coordinates and local circumstance on the center line, and a series of orthographic projection maps which show the regions of visibility of both partial and central phases for every eclipse from 1986 through 2035 are also provided.

  4. Moon eclipse from 21 december 2010 in Romania

    NASA Astrophysics Data System (ADS)

    Gaina, Alex; Haus, Marian; Conovici, Matei; Vasiliu, Dan

    2010-12-01

    The authors discuss the Total Moon's eclipse from 21 december 2010, their circumstances for Romania and Central Europe. One notes that the informations from the NASA eclipses website do not inform correctly about the observability of the initial penumbral phase (P1-U1) of the eclipse. The same reffer to the Anuarul Astronomic Roman, published by the Institutul Astronomic Roman for 2010. By contrary the web site by Fred Espenac informed correctly the astronomical community. The Moon setted before the begining of the penumbral phase of the eclipse.

  5. Campaign Photometry During The 2010 Eclipse Of Epsilon Aurigae

    NASA Astrophysics Data System (ADS)

    Hopkins, Jeff; Stencel, R. E.

    2011-01-01

    Epsilon Aurigae is a long period (27.1 years) eclipsing binary star system with an eclipse that lasts nearly 2 years, but with severe ambiguities about component masses and shape. The current eclipse began on schedule in August of 2009. During the previous, 1982-1984 eclipse, an International Campaign was formed to coordinate a detailed study of the system. While that Campaign was deemed successful, the evolutionary status of the star system remained unclear. Epsilon Aurigae has been observed nearly continuously since the 1982 eclipse. The current Campaign was officially started in 2006. In addition to a Yahoo forum we have a dedicated web site and more than 18 online newsletters reporting photometry, spectroscopy, interferometry and polarimetry data. High quality UBVRIJH band photometric data since before the start of the current eclipse has been submitted. We explore the color differences among the light curves in terms of eclipse phases and archival data. At least one new model of the star system has been proposed since the current Campaign began: a low mass but very high luminosity F star plus a B star surrounded by a debris disk. The current eclipse and in particular the interferometry and spectroscopic data have caused new thoughts on defining eclipsing variable star contact points and phases of an eclipse. Second contact may not be the same point as start of totality and third contact may not be the same point as the start of egress and end of totality. In addition, the much awaited mid-eclipse brightening may or may not have appeared. This paper identifies the current Campaign contributors and the photometric data. This work was supported in part by the bequest of William Herschel Womble in support of astronomy at the University of Denver, by NSF grant 1016678 to the University of Denver.

  6. Photometric Analysis of Eclipsing Binary Az Vir

    NASA Astrophysics Data System (ADS)

    Neugarten, Andrew; Akiba, Tatsuya; Gokhale, Vayujeet

    2018-06-01

    We present photometric analysis of the eclipsing binary star system Az Vir. Standard BVR filter data were obtained using the 17-inch PlaneWave Instruments CDK telescope at the Truman State University Observatory in Kirksville, Mo and the 31-inch NURO telescope at the Lowell Observatory complex in Flagstaff, AZ. We apply an eight-term truncated Fourier fit to the light curves generated from these data to confirm the classification of Az Vir as a W Ursae Majoris-type eclipsing variable, using criteria specified by Rucinski (1997). We also calculate the values for the O’Connell Effect Ratio (OER) and the Light Curve Asymmetry (LCA) to quantify the asymmetry in the BVR light curves. In addition, we use data provided by the SuperWASP mission to perform long term O-C (observed minus calculated) analysis on the system to determine if and how its period is changing.

  7. F-106 tow cable attachment and release mechanism for Eclipse program

    NASA Technical Reports Server (NTRS)

    1997-01-01

    View of the tow cable attachment and release mechanism forward of the cockpit on the QF-106 Eclipse aircraft. This mechanism held and then released the Vectran rope used to tow the QF-106 behind an Air Force C-141A. In 1997 and 1998, the Dryden Flight Research Center at Edwards, California, supported and hosted a Kelly Space & Technology, Inc. project called Eclipse, which sought to demonstrate the feasibility of a reusable tow-launch vehicle concept. The project goal was to successfully tow, inflight, a modified QF-106 delta-wing aircraft with an Air Force C-141A transport aircraft. This would demonstrate the possibility of towing and launching an actual launch vehicle from behind a tow plane. Dryden was the responsible test organization and had flight safety responsibility for the Eclipse project. Dryden provided engineering, instrumentation, simulation, modification, maintenance, range support, and research pilots for the test program. The Air Force Flight Test Center (AFFTC), Edwards, California, supplied the C-141A transport aircraft and crew and configured the aircraft as needed for the tests. The AFFTC also provided the concept and detail design and analysis as well as hardware for the tow system and QF-106 modifications. Dryden performed the modifications to convert the QF-106 drone into the piloted EXD-01 (Eclipse eXperimental Demonstrator-01) experimental aircraft. Kelly Space & Technology hoped to use the results gleaned from the tow test in developing a series of low-cost, reusable launch vehicles. These tests demonstrated the validity of towing a delta-wing aircraft having high wing loading, validated the tow simulation model, and demonstrated various operational procedures, such as ground processing of in-flight maneuvers and emergency abort scenarios.

  8. Poster 16: Eclipse-induced changes of Titan's meteorology at equinox

    NASA Astrophysics Data System (ADS)

    Tokano, Tetsuya

    2016-06-01

    Titan experiences solar eclipses by Saturn on ˜20 consecutive orbits around equinox for durations of up to ˜6 hours. The impact of these eclipses on Titan's surface, lower atmosphere and middle atmosphere is investigated by a global climate model. When an eclipse commences, the surface temperature on the subsaturnian side drops by up to 0.3 K, so that the diurnal maximum surface temperature remains lower than on the antisaturnian side, which is never eclipsed. By contrast, the tropospheric air temperature does not abruptly decrease during the eclipses because of the large thermal inertia, but the diurnal mean temperature slightly decreases. The surface wind at low latitudes becomes less gusty in the presence of eclipse due to damping of turbulence. The troposphere outside the planetary boundary layer is not sensitive to eclipses. In most parts of the stratosphere and mesosphere the temperature decreases by up to 2 K due to eclipses, but there are also layers, which experience relative warming due to thermal contraction of the underlying layers. The temperature in the middle atmosphere rapidly recovers after the end of the eclipse season. Eclipse-induced cooling and warming changes the zonal wind speed by a few m/s due to thermal wind adjustment to changing latitudinal temperature gradients.

  9. Modeling transiting circumstellar disks: characterizing the newly discovered eclipsing disk system OGLE LMC-ECL-11893

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

    Scott, Erin L.; Mamajek, Eric E.; Pecaut, Mark J.

    2014-12-10

    We investigate the nature of the unusual eclipsing star OGLE LMC-ECL-11893 (OGLE J05172127-6900558) in the Large Magellanic Cloud recently reported by Dong et al. The eclipse period for this star is 468 days, and the eclipses exhibit a minimum of ∼1.4 mag, preceded by a plateau of ∼0.8 mag. Spectra and optical/IR photometry are consistent with the eclipsed star being a lightly reddened B9III star of inferred age ∼150 Myr and mass ∼4 M {sub ☉}. The disk appears to have an outer radius of ∼0.2 AU with predicted temperatures of ∼1100-1400 K. We model the eclipses as being duemore » to either a transiting geometrically thin dust disk or gaseous accretion disk around a secondary object; the debris disk produces a better fit. We speculate on the origin of such a dense circumstellar dust disk structure orbiting a relatively old low-mass companion, and on the similarities of this system to the previously discovered EE Cep.« less

  10. The two variables in the triple system HR 6469 = V819 Her: One eclipsing, one spotted

    NASA Technical Reports Server (NTRS)

    Van Hamme, Walter V.; Hall, Douglas S.; Hargrove, Adam W.; Henry, Gregory W.; Wasson, Rick; Barksdale, William S.; Chang, Sandy; Fried, Robert E.; Green, Charles L.; Lines, Helen C.

    1994-01-01

    A complete BV light curve, from 14 nights of good data obtained with the Vanderbilt University-Tennessee State University (VU-TSU) automatic telescope, are presented and solved with the Wilson-Devinney program. Third light is evaluated, with the companion star brighter by 0.58(sup m) in V and 0.11(sup m) in B. The eclipses are partial. Inferred color indices yield F2 V and F8 V for the eclipsing pair and G8 IV-III for the distant companion star. After removing the variability due to eclipses, we study the residual variability of the G8 IV-III star over the ten years 1982 to 1992. Each yearly light curve is fit with a two-spot model. Three relatively long-lived spots are identified, with rotation periods of 85.9(sup d), 85.9(sup d), and 86.1(sup d). The weak and intermittent variability is understood because the G8 IV-III star has a Rossby number at the threshold for the onset of heavy spottedness.

  11. Data Collection During the Great American Eclipse

    NASA Astrophysics Data System (ADS)

    Vernier, Dave

    2017-12-01

    I am lucky enough (and old enough) to have seen three total eclipses. About a year ago, I became aware of the total eclipse that was coming to the United States on August 21, 2017. Because I knew how exciting a total eclipse can be, I spent a lot of time encouraging people to travel to the zone of totality if they possibly could. I also encouraged teachers to turn this event into a STEM lesson by taking data. We asked teachers to join us in collecting data during the eclipse and to share it. The people collecting these data were either teachers or former teachers (like me). Many times, the sensors were mounted with duct tape and rubber bands, but we got some great data!

  12. Ultraviolet spectral variations of symbiotic nova PU Vul during and after second eclipse

    NASA Astrophysics Data System (ADS)

    Sanad, M. R.

    2016-12-01

    I have analyzed spectral data of the symbiotic nova PU Vul observed with the International Ultraviolet Explorer (IUE) during the period 1993-1996. The study concentrated on the two sources of nebular emitting regions, the first is a nebula around the white dwarf partially eclipsed by a cool giant star and the second is a very extended nebular region not affected by the eclipse of the giant star. I concentrated on the N IV] 1486 Å and C IV 1550 Å emission lines produced in the first region and N III] 1750 Å and C III] 1909 Å emission lines produced in the second region very far from the giant star.

  13. Light curve solutions of the eclipsing eccentric binaries KIC 8111622, KIC 10518735, KIC 8196180 and their out-of-eclipse variability

    NASA Astrophysics Data System (ADS)

    Kjurkchieva, Diana P.; Vasileva, Doroteya L.

    2018-02-01

    We determined the orbits and stellar parameters of three eccentric eclipsing binaries by light curve solutions of their Kepler data. KIC 8111622 and KIC 10518735 undergo total eclipses while KIC 8196180 reveals partial eclipses. The target components are G and K stars, excluding the primary of KIC 8196180 which is early F star. KIC 8196180 reveals well-visible tidally-induced feature at periastron, i.e. it is an eclipsing heartbeat star. The characteristics of the observed periastron feature (shape, width and amplitude) confirm the theoretical predictions. There are additional out-of-eclipse variations of KIC 8196180 with the orbital period which may be explained by spot activity of synchronously rotating component. Besides worse visible periastron feature KIC 811162 exhibits small-amplitude light variations whose period is around 2.3 times shorter than the orbital one. These oscillations were attributed to spot(s) on asynchronously rotating component.

  14. A Case Study in High Contrast Coronagraph for Planet Discovery: The Eclipse Concept and Support Laboratory Experience

    NASA Technical Reports Server (NTRS)

    Trauger, John T.

    2005-01-01

    Eclipse is a proposed NASA Discovery mission to perform a sensitive imaging survey of nearby planetary systems, including a survey for jovian-sized planets orbiting Sun-like stars to distances of 15 pc. We outline the science objectives of the Eclipse mission and review recent developments in the key enabling technologies. Eclipse is a space telescope concept for high-contrast visible-wavelength imaging and spectrophotometry. Its design incorporates a telescope with an unobscured aperture of 1.8 meters, a coronographic camera for suppression of diffracted light, and precise active wavefront correction for the suppression of scattered background light. For reference, Eclipse is designed to reduce the diffracted and scattered starlight between 0.33 and 1.5 arcseconds from the star by three orders of magnitude compared to any HST instrument. The Eclipse mission provides precursor science exploration and technology experience in support of NASA's Terrestrial Planet Finder (TPF) program.

  15. The Solar Eclipse Predictions of Chiljeongsam-Oepyeon in Early Choseon

    NASA Astrophysics Data System (ADS)

    Ahn, Young Sook; Lee, Yong Sam

    2004-12-01

    The history books of East Asia about astronomical phenomena have the more records of the solar eclipse frequently than any other ones. It is because traditionally, the solar eclipse meaned the fate of dynasty and the king's rule. The Sun, the biggest thing in the heaven symbolized the king, and the solar eclipse foresaw that the king had the problem in private including the body, and the country might suffer from difficulties in a great scale. So the king and all of the ministers used to gather to hold a ceremony named Gusikrye which solar eclipse may pass safely. Consequently, kings always had concernments on collecting informations of solar eclipse. Inspite of importance of solar eclipse predictions, but at the beginning of the Choseon, the predictions of the solar eclipse didn't fit. King Sejong compiled the Chiljeongsan-naepion and the Chiljeongsan-oepyeon to calculate the celestial phenomena including the solar eclipse. By the publications of these two books, the calendar making system of Choseon was firmly established. The Chiljeongsan-oepyeon adopted Huihui calendar of Arabia. The Solar eclipse predictions of Chiljeongsan-oepyeon were relative correct compared to modern method in early Choseon dynasty.

  16. The solar eclipse: a natural meteorological experiment

    PubMed Central

    2016-01-01

    A solar eclipse provides a well-characterized reduction in solar radiation, of calculable amount and duration. This captivating natural astronomical phenomenon is ideally suited to science outreach activities, but the predictability of the change in solar radiation also provides unusual conditions for assessing the atmospheric response to a known stimulus. Modern automatic observing networks used for weather forecasting and atmospheric research have dense spatial coverage, so the quantitative meteorological responses to an eclipse can now be evaluated with excellent space and time resolution. Numerical models representing the atmosphere at high spatial resolution can also be used to predict eclipse-related changes and interpret the observations. Combining the models with measurements yields the elements of a controlled atmospheric experiment on a regional scale (10–1000 km), which is almost impossible to achieve by other means. This modern approach to ‘eclipse meteorology’ as identified here can ultimately improve weather prediction models and be used to plan for transient reductions in renewable electricity generation. During the 20 March 2015 eclipse, UK electrical energy demand increased by about 3 GWh (11 TJ) or about 4%, alongside reductions in the wind and photovoltaic electrical energy generation of 1.5 GWh (5.5 TJ). This article is part of the themed issue ‘Atmospheric effects of solar eclipses stimulated by the 2015 UK eclipse’. PMID:27550768

  17. 2017 Solar Eclipse Event

    NASA Image and Video Library

    2017-06-11

    Sylvester Dorsey III, avionics lead for the Europa Deorbit Stage Team in Marshall's Engineering Directorate, is joined during Marshall's eclipse-viewing event by his three children, from left, Sylvester IV, Sidney and Sakari. Though Huntsville was south of the path of totality, the Dorseys were among those awestruck by the natural phenomenon. The Huntsville area experienced 97 percent occultation, nearly a complete blocking out of the sun by the orbit of Earth's moon. The next opportunity to view a solar eclipse in the eastern and central United States will occur in April 2024.

  18. Profiling LC-DAD-ESI-TOF MS method for the determination of phenolic metabolites from avocado (Persea americana).

    PubMed

    Hurtado-Fernández, Elena; Carrasco-Pancorbo, Alegría; Fernández-Gutiérrez, Alberto

    2011-03-23

    A powerful HPLC-DAD-ESI-TOF MS method was established for the efficient identification of the chemical constituents in the methanolic extracts of avocado (Persea americana). Separation and detection conditions were optimized by using a standard mix containing 39 compounds belonging to phenolic acids and different categories of flavonoids, analytes that could be potentially present in the avocado extracts. Optimum LC separation was achieved on a Zorbax Eclipse Plus C18 analytical column (4.6×150 mm, 1.8 μm particle size) by gradient elution with water+acetic acid (0.5%) and acetonitrile as mobile phases, at a flow rate of 1.6 mL/min. The detection was carried out by ultraviolet-visible absorption and ESI-TOF MS. The developed method was applied to the study of 3 different varieties of avocado, and 17 compounds were unequivocally identified with standards. Moreover, around 25 analytes were tentatively identified by taking into account the accuracy and isotopic information provided by TOF MS.

  19. Eclipsing binary stars with a δ Scuti component

    NASA Astrophysics Data System (ADS)

    Kahraman Aliçavuş, F.; Soydugan, E.; Smalley, B.; Kubát, J.

    2017-09-01

    Eclipsing binaries with a δ Sct component are powerful tools to derive the fundamental parameters and probe the internal structure of stars. In this study, spectral analysis of six primary δ Sct components in eclipsing binaries has been performed. Values of Teff, v sin I, and metallicity for the stars have been derived from medium-resolution spectroscopy. Additionally, a revised list of δ Sct stars in eclipsing binaries is presented. In this list, we have only given the δ Sct stars in eclipsing binaries to show the effects of the secondary components and tidal-locking on the pulsations of primary δ Sct components. The stellar pulsation, atmospheric and fundamental parameters (e.g. mass, radius) of 92 δ Sct stars in eclipsing binaries have been gathered. Comparison of the properties of single and eclipsing binary member δ Sct stars has been made. We find that single δ Sct stars pulsate in longer periods and with higher amplitudes than the primary δ Sct components in eclipsing binaries. The v sin I of δ Sct components is found to be significantly lower than that of single δ Sct stars. Relationships between the pulsation periods, amplitudes and stellar parameters in our list have been examined. Significant correlations between the pulsation periods and the orbital periods, Teff, log g, radius, mass ratio, v sin I and the filling factor have been found.

  20. The X-ray eclipse of the LMC binary CAL 87

    NASA Technical Reports Server (NTRS)

    Schmidtke, P. C.; Mcgrath, T. K.; Cowley, A. P.; Frattare, L. M.

    1993-01-01

    ROSAT-PSPC observations of the LMC eclipsing binary CAL 87 show a short-duration, shallow X-ray eclipse which coincides in phase with the primary optical minimum. Characteristics of the eclipse suggest the X-ray emitting region is only partially occulted. Similarities with the eclipse of the accretion-disk corona in X 1822-37 are discussed. However, no temperature variation through eclipse is found for CAL 87. A revised orbital period, combining published data and recent optical photometry, is given.

  1. 2017 Solar Eclipse, Ames Research Center

    NASA Image and Video Library

    2017-08-21

    Taking a break from his duties at the Ames Vertical Gun Range to look up at the eclipse over Ames Research Center in Mountain View Adam Parrish not only views but wears, on his forehead, the image of the 2017 Solar eclipse at 09:20:56 on August 21, 2017.

  2. 78 FR 49908 - Airworthiness Directives; Eclipse Aerospace, Inc. Airplanes

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-16

    ... Airworthiness Directives; Eclipse Aerospace, Inc. Airplanes AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Final rule. SUMMARY: We are adopting a new airworthiness directive (AD) for all Eclipse Aerospace... Eclipse Aerospace, Inc., 26 East Palatine Road, Wheeling, Illinois 60090; telephone: (877) 373-7978...

  3. A spectroscopic investigation of the eclipsing binary Epsilon Aurigae

    NASA Technical Reports Server (NTRS)

    Balachandran, Suchitra

    1991-01-01

    The objectives were to examine, in detail, the spectra of the eclipsing binary Epsilon Aurigae taken with the IUE satellite telescope during the 1982 to 1984 eclipse. All of the low resolution spectra were analyzed and UV light curves are presented. The primary findings are as follows: (1) a constant eclipse depth from 1600 A to longer wavelengths and a sharp drop in the eclipse depth from 1600 to 1200 A; (2) the absence of large amplitude fluctuations in the UV as expected from a Cepheid primary; and (3) equal ingress and egress times in contradiction to that interpreted from visible light curves. The effects of these findings on the eclipse geometry are being studied.

  4. Solar Eclipse

    Atmospheric Science Data Center

    2013-04-16

    ... View Larger Image Within that narrow window during a solar eclipse where an observer on Earth can watch the Moon's shadow obscure ... of the imagery acquired during Terra orbit 20920. The panels cover an area of about 380 kilometers x 2909 kilometers and use data ...

  5. Io in Eclipse, Movie

    NASA Technical Reports Server (NTRS)

    2001-01-01

    Glowing spots of hot lava and ethereal auroral emissions are highlighted against blackness in this sequence of 48 frames from NASA's Cassini spacecraft, which show Jupiter's moon Io in the darkness of the giant planet's shadow.

    The sequence was recorded over a two-hour interval that spanned nearly an entire eclipse on Jan. 1, 2001. Although no sunlight shines on the moon during an eclipse, two types of glows can be seen. The bright points of light are the glows of hot lava from active volcanoes. The brightest is the volcano Pele, which appears to be erupting steadily despite its great intensity. To the right of Pele and slightly above it is a pair of bright spots associated with the volcano Pillan, the source of a major eruption in 1997. NASA's Galileo spacecraft and Hubble Space Telescope saw that 1997 eruption of Pillan dwarf the energy output from neighboring Pele, but Pillan's eruption has waned over the past 30 months to the pair of small hot spots seen here. Another volcano, seen below and to the right of Pele, varies on a time scale of days. This sequence of images illustrates the great variations in intensity and longevity of Io's volcanic eruptions.

    The second type of glow seen on Io during eclipse is a set of faint, diffuse emissions due to atmospheric auroras. Similar to the aurora borealis and aurora australis on Earth, Io's auroras are caused by the collisions of charged particles with gases in Io's tenuous atmosphere. A faint ring encircles the moon, while brighter glows are concentrated near the moon's equator. These equatorial glows are seen here gradually shifting clockwise in location as the eclipse progresses, due to the changing orientation of Jupiter's magnetic field. This is a new result which confirms that these visible auroras, like their counterparts seen at ultraviolet wavelengths, are caused by electrical currents that flow between Io and Jupiter.

    The original images were taken through a clear filter of Cassini's narrow

  6. The eclipse of the Sun from 20 May 2015

    NASA Astrophysics Data System (ADS)

    Tiron, S. D.

    2015-04-01

    The interview of the Radio Moldova with astronomer about the coming Eclipse of the Sun, included the following topics: 1) The circumstances of the Total eclipse 2) The circumstances of the Partial Eclipse in the Republic of Moldova 3) Protection of eyes during Observations

  7. 78 FR 30243 - Airworthiness Directives; Eclipse Aerospace, Inc. Airplanes

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-22

    ... Airworthiness Directives; Eclipse Aerospace, Inc. Airplanes AGENCY: Federal Aviation Administration (FAA), DOT... (AD) for all Eclipse Aerospace, Inc. Model EA500 airplanes equipped with Avio, Avio with ETT, or Avio... identified in this proposed AD, contact Eclipse Aerospace, Inc. 26 East Palatine Road, Wheeling, Illinois...

  8. Photometric Study of The Solar Type, Total Eclipsing Binary, TYC 2853-18-1

    NASA Astrophysics Data System (ADS)

    Samec, Ronald G.; Figg, E. R.; Faulkner, D.; Van Hamme, W.

    2009-12-01

    We present an analysis of the Solar-Type eclipsing binary, TYC 2853-18-1 (Persei), based on observations taken at the National Undergraduate Research Observatory (NURO) and the Southeastern Association for Research in Astronomy (SARA) in the Fall, 2007 and Spring, 2008. Light curves, a period study and a synthetic light curve solution are presented for this variable which was recently discovered by TYCHO as an eclipsing binary (2006, IBVS 5700). Our CCD observations of TYC 2853-18-1 [GSC 2853 0018, RA(2000) = 02h 47m 07.996s, DEC(2000) = +41° 22’ 32.80"] were taken on 20,27 December, 2007 at Lowell Observatory with the 0.81-m reflector with NURO time and 25 November, 3 December, 2007 and 19 February, 2008 via remote observing from Kitt Peak with SARA. NURO observations were take with the thermoelectrically cooled (<-100C) 2KX2K CCD NASACAM. Standard BVRcIc Johnson-Cousins filters were used. Our light curve solution was calculated with the 2004 Wilson code. Mean times of eclipse include, HJDMinI = 2454516.6131(±0.0005), 2454440.52974(±0.00008), 2454438.7605 (±0.0001), 2454462.6464 (±0.0003), HJDMinII = 2454455.71985 (±0.00060), 255462.7943 (±0.0002). These, including the epoch by ROTSE (2006, IBVS 5699) and the epoch calculated by the Wilson code, yielded the following ephemeris: HJD Hel Min I =2451370.8753(±.0.0010)d + 0.2949039 (±0.0000001)E Our unspotted Wilson code solution reveals TYC 2853-18-1 to be a W-type W UMa contact binary with unequal eclipse depths (amplitudes are 0.72 and 0.61 mags in V). It has shallow contact (8% fill-out) and a brief, but total eclipse. Its curves dictate a mass ratio of 2.62±0.01, a component temperature difference of only 73±5 ° K and an inclination of 82.0±0.2°. Spot activity is indicated by night to night variations. We wish to thank the NURO and SARA for their allocation of observing time, as well as NASA and the AAS for their support in paying for travel and publication expenses.

  9. The Totality App — General Lessons and Future Eclipses

    NASA Astrophysics Data System (ADS)

    Bennett, Jeffrey

    2018-06-01

    With the excitement around the 2017 eclipse, I worked with an app development company to create the Totality app, which featured eclipse predictions from the code of Xavier Jubier. We have since updated the app for future eclipses, including a Spanish version given the upcoming eclipses in Chile/Argentina. I will briefly discuss the current app, the process through which we developed it, and relevant lessons learned along the way that may be useful to others interested in developing apps for astronomy education.

  10. Short apsidal period of three eccentric eclipsing binaries discovered in the Large Magellanic Cloud

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

    Hong, Kyeongsoo; Lee, Chung-Uk; Kim, Seung-Lee

    2014-06-01

    We present new elements of apsidal motion in three eccentric eclipsing binaries located in the Large Magellanic Cloud. The apsidal motions of the systems were analyzed using both light curves and eclipse timings. The OGLE-III data obtained during the long period of 8 yr (2002-2009) allowed us to determine the apsidal motion period from their analyses. The existence of third light in all selected systems was investigated by light curve analysis. The O – C diagrams of EROS 1018, EROS 1041, and EROS 1054 were analyzed using the 30, 44, and 26 new times of minimum light, respectively, determined frommore » full light curves constructed from EROS, MACHO, OGLE-II, OGLE-III, and our own observations. This enabled a detailed study of the apsidal motion in these systems for the first time. All of the systems have a significant apsidal motion below 100 yr. In particular, EROS 1018 shows a very fast apsidal period of 19.9 ± 2.2 yr in a detached system.« less

  11. 2017 Total Solar Eclipse Across America Promo

    NASA Image and Video Library

    2017-08-10

    On Monday, August 21, 2017, all of North America will be treated to an eclipse of the sun. Anyone within the path of totality can see one of nature’s most awe inspiring sights - a total solar eclipse.

  12. Solar Eclipse

    Atmospheric Science Data Center

    2013-04-19

    ... June 10, 2002 the Moon obscured the central portion of the solar disk in a phenomenon known as an annular solar eclipse. Partial phases of ... to obscure about 75 percent of the solar disk. The two scenes are geolocated to adjacent paths within World Reference System-2. ...

  13. Total Solar Eclipse of 1997 March 9

    NASA Technical Reports Server (NTRS)

    Espenak, Fred; Anderson, Jay

    1995-01-01

    A total eclipse of the Sun will be visible from Asia and the Pacific Ocean on 1997 March 9. The path of the Moon's umbral shadow begins in eastern Kazakhstan and travels through Mongolia and eastern Siberia, where it swings northward to end at sunset in the Arctic Ocean. A partial eclipse will be seen within the much broader path of the Moon's penumbral shadow, which includes eastern Asia, the northern Pacific, and the northwest corner of North America. Detailed predictions for this event are presented and include besselian elements, geographic coordinates of the path of totality, physical ephemeris of the umbra, topocentric limb profile corrections, local circumstances for 280 cities, maps of the eclipse path, weather prospects, the lunar limb profile, and the sky during totality. Tips and suggestions are also given on how to safely view and photograph the eclipse.

  14. Total Solar Eclipse of 2001 June 21

    NASA Technical Reports Server (NTRS)

    Espenak, Fred; Anderson, Jay

    1999-01-01

    On 2001 June 21, a total eclipse of the Sun will be visible from within a narrow corridor which traverses the Southern Hemisphere. The path of the Moon's umbral shadow begins in the South Atlantic, crosses southern Africa and Madagascar, and ends at sunset in the Indian Ocean. A partial eclipse will be seen within the much broader path of the Moon's penumbral shadow, which includes eastern South America and the southern two thirds of Africa. Detailed predictions for this event are presented and include besselian elements, geographic coordinates of the path of totality, physical ephemeris of the umbra, topocentric limb profile corrections, local circumstances for approximately 350 cities, maps of the eclipse path, weather prospects, the lunar limb profile and the sky during totality. Tips and suggestions are also given on how to safely view and photograph the eclipse.

  15. Eclipsing binary stars as tests of gravity theories - The apsidal motion of AS Camelopardalis

    NASA Technical Reports Server (NTRS)

    Maloney, Frank P.; Guinan, Edward F.; Boyd, Patricia T.

    1989-01-01

    AS Camelopardalis is an 8th-magnitude eclipsing binary that consists of two main-sequence (B8 V and a B9.5 V) components in an eccentric orbit (e = 0.17) with an orbital period of 3.43 days. Like the eccentric eclipsing system DI Herculis, and a few other systems, AS Cam is an important test case for studying relativistic apsidal motion. In these systems, the theoretical general relativistic apsidal motion is comparable to that expected from classical effects arising from tidal and rotational deformation of the stellar components. Accurate determinations of the orbital and stellar properties of AS Cam have been made by Hilditch (1972) and Khalliulin and Kozyreva (1983) that permit the theoretical relativistic and classical contributions to the apsidal motion to be determined reasonably well. All the published timings of primary and secondary minima have been gathered and supplemented with eclipse timings from 1899 to 1920 obtained from the Harvard plate collection. Least-squares solutions of the eclipse timings extending over an 80 yr interval yield a smaller than expected apsidal motion, in agreement with that found by Khalliulin and Kozyreva from a smaller set of data. The observed apsidal motion for AS Cam is about one-third that expected from the combined relativistic and classical effects. Thus, AS Cam joins DI Her in having an observed apsidal motion significantly less than that predicted from theory.

  16. 2017 Total Solar Eclipse - ISS Transit

    NASA Image and Video Library

    2017-08-21

    The International Space Station, with a crew of six onboard, is seen in silhouette as it transits the Sun at roughly five miles per second during a partial solar eclipse, Monday, Aug. 21, 2017 near Banner, Wyoming. Onboard as part of Expedition 52 are: NASA astronauts Peggy Whitson, Jack Fischer, and Randy Bresnik; Russian cosmonauts Fyodor Yurchikhin and Sergey Ryazanskiy; and ESA (European Space Agency) astronaut Paolo Nespoli. A total solar eclipse swept across a narrow portion of the contiguous United States from Lincoln Beach, Oregon to Charleston, South Carolina. A partial solar eclipse was visible across the entire North American continent along with parts of South America, Africa, and Europe. Photo Credit: (NASA/Joel Kowsky)

  17. 2017 Solar Eclipse Event

    NASA Image and Video Library

    2017-06-11

    Robert Wilson of the Solar/Solar terrestrial Studies team at the National Space Science and Technology Center, a joint research and collaborative think tank partnership of the University of Alabama in Huntsville (UAH) and the Marshall Space Flight Center, adjusts his telescope which is set up as a viewing opportunity for MSFC employees prior to the August 21, 2017 solar eclipse event. The Huntsville area experienced 97 percent occultation, nearly a complete blocking out of the sun by the orbit of Earth's moon. The next opportunity to view a solar eclipse in the eastern and central United States will occur in April 2024.

  18. Statistical analysis of geomagnetic field variations during solar eclipses

    NASA Astrophysics Data System (ADS)

    Kim, Jung-Hee; Chang, Heon-Young

    2018-04-01

    We investigate the geomagnetic field variations recorded by INTERMAGNET geomagnetic observatories, which are observed while the Moon's umbra or penumbra passed over them during a solar eclipse event. Though it is generally considered that the geomagnetic field can be modulated during solar eclipses, the effect of the solar eclipse on the observed geomagnetic field has proved subtle to be detected. Instead of exploring the geomagnetic field as a case study, we analyze 207 geomagnetic manifestations acquired by 100 geomagnetic observatories during 39 solar eclipses occurring from 1991 to 2016. As a result of examining a pattern of the geomagnetic field variation on average, we confirm that the effect can be seen over an interval of 180 min centered at the time of maximum eclipse on a site of a geomagnetic observatory. That is, demonstrate an increase in the Y component of the geomagnetic field and decreases in the X component and the total strength of the geomagnetic field. We also find that the effect can be overwhelmed, depending more sensitively on the level of daily geomagnetic events than on the level of solar activity and/or the phase of solar cycle. We have demonstrated it by dividing the whole data set into subsets based on parameters of the geomagnetic field, solar activity, and solar eclipses. It is suggested, therefore, that an evidence of the solar eclipse effect can be revealed even at the solar maximum, as long as the day of the solar eclipse is magnetically quiet.

  19. Public Education and Outreach for Observing Solar Eclipses and Transits

    NASA Astrophysics Data System (ADS)

    Pasachoff, Jay M.

    2015-08-01

    The general public is often very interested in observing solar eclipses, with widespread attention from newspapers and other sources often available only days before the events. Recently, the 2012 eclipse's partial phases in Australia and the 2015 eclipse's partial phases throughout Europe as well as western Asia and northern Africa, were widely viewed. The 21 August 2017 eclipse, whose totality will sweep across the Continental United States from northwest to southeast, will have partial phases visible throughout the U.S., Canada, Mexico, Central America, and into South America. The 2019 and 2020 partial phases of total eclipses will be visible throughout South America, and partial phases from annular eclipses will be visible from other parts of the world. The 9 May 2016 transit of Mercury will be best visible from the Western Hemisphere, Europe, and Africa. Many myths and misunderstandings exist about the safety of observing partial phases, and it is our responsibility as astronomers and educators to transmit accurate information and to attempt the widest possible distribution of such information. The Working Group on Public Education at Eclipses and Transits, formerly of Commission 46 on Education and Development and now of New Commission 11, tries to coordinate the distribution of information. In collaboration with the Solar Division's Working Group on Solar Eclipses, their website at http://eclipses.info is a one-stop shop for accurate information on how to observe eclipses, why it is interesting to do so, where they will be visible (with links to online maps and weather statistics), and how encouraging students to observe eclipses can be inspirational for them, perhaps even leading them to realize that the Universe can be understood and therefore renewing the strength of their studies. Links to information about transits of Mercury and Venus are also included.

  20. Eclipse takeoff and flight

    NASA Technical Reports Server (NTRS)

    1998-01-01

    This 25-second clip shows the QF-106 'Delta Dart' tethered to the USAF C-141A during takeoff and in flight. NASA Dryden Flight Research Center, Edwards, California, supported a Kelly Space and Technology, Inc. (KST)/U.S. Air Force project known as Eclipse, which demonstrated a reusable tow launch vehicle concept. The purpose of the project was to demonstrate a reusable tow launch vehicle concept that had been conceived and patented by KST. Kelly Space obtained a contract with the USAF Research Laboratory for the tow launch demonstration project under the Small Business Innovation Research (SBIR) program. The USAF SBIR contract included the modifications to turn the QF-106 into the Experimental Demonstrator #1 (EXD-01), and the C141A aircraft to incorporate the tow provisions to link the two aircraft, as well as conducting flight tests. The demonstration consisted of ground and flight tests. These tests included a Combined Systems Test of both airplanes joined by a tow rope, a towed taxi test, and six towed flights. The primary goal of the project was demonstrating the tow phase of the Eclipse concept using a scaled-down tow aircraft (C-141A) and a representative aerodynamically-shaped aircraft (QF-106A) as a launch vehicle. This was successfully accomplished. On December 20, 1997, NASA research pilot Mark Stucky flew a QF-106 on the first towed flight behind an Air Force C-141 in the joint Eclipse project with KST to demonstrate the reusable tow launch vehicle concept developed by KST. Kelly hoped to use the data from the tow tests to validate a tow-to-launch procedure for reusable space launch vehicles. Stucky flew six successful tow tests between December 1997 and February 6, 1998. On February 6, 1998, the sixth and final towed flight brought the project to a successful completion. Preliminary flight results determined that the handling qualities of the QF-106 on tow were very stable; actual flight measured values of tow rope tension were well within predictions

  1. Lunar eclipses: Probing the atmosphere of an inhabited planet

    NASA Astrophysics Data System (ADS)

    García Muñoz, A.

    2013-04-01

    The Moon's brightness during a lunar eclipse is indicative of the composition, cloudiness and aerosol loading of the Earth's atmosphere. The idea of using lunar eclipse observations to characterize the Earth's atmosphere is not new, but the interest raised by the prospects of discovering Earth-like exoplanets transiting their host stars has brought renewed attention to the method. We review some recent efforts made in the prediction and interpretation of lunar eclipses. We also comment on the contribution of the lunar eclipse theory to the refractive theory of planetary transits.

  2. GMRT DISCOVERY OF PSR J1544+4937: AN ECLIPSING BLACK-WIDOW PULSAR IDENTIFIED WITH A FERMI-LAT SOURCE

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

    Bhattacharyya, B.; Roy, J.; Gupta, Y.

    2013-08-10

    Using the Giant Metrewave Radio Telescope, we performed deep observations to search for radio pulsations in the directions of unidentified Fermi-Large Area Telescope {gamma}-ray sources. We report the discovery of an eclipsing black-widow millisecond pulsar, PSR J1544+4937, identified with the uncataloged {gamma}-ray source FERMI J1544.2+4941. This 2.16 ms pulsar is in a 2.9 hr compact circular orbit with a very low mass companion (M{sub c} > 0.017M{sub Sun }). At 322 MHz this pulsar is found to be eclipsing for 13% of its orbit, whereas at 607 MHz the pulsar is detected throughout the low-frequency eclipse phase. Variations in themore » eclipse ingress phase are observed, indicating a clumpy and variable eclipsing medium. Moreover, additional short-duration absorption events are observed around the eclipse boundaries. Using the radio timing ephemeris we were able to detect {gamma}-ray pulsations from this pulsar, confirming it as the source powering the {gamma}-ray emission.« less

  3. A Coral Sea Rehearsal for the Eclipse Megamovie

    NASA Astrophysics Data System (ADS)

    Hudson, H. S.; Davey, A. R.; Ireland, J.; Jones, L.; Mcintosh, S. W.; Paglierani, R.; Pasachoff, J. M.; Peticolas, L. M.; Russell, R. M.; Suarez Sola, F. I.; Sutherland, L.; Thompson, M. J.

    2012-12-01

    The "Eclipse on the Coral Sea" - 13/14 November 2012 (GMT/Australia) - will have happened already. Our intention is to have used this opportunity as a trial run for the eclipse in 2017, which features 1.5 hours of totality across the whole width of the continental US. Conceived first and foremost as an education and public outreach activity, the plan is to engage the public in solar science and technology by providing a way for them to include images they have taken of the solar eclipse, into a movie representation of coronal evolution in time. This project will assimilate as much eclipse photography as possible from the public. The resulting movie(s) will cover all ranges of expertise, and at the basic smartphone or hand-held digital camera level, we expect to have obtained a huge number of images in the case of good weather conditions. The capability of modern digital technology to handle such a data flow is new. The basic purpose of this and the 2017 Megamovie observations is to explore this capability and its ability to engage people from many different communities in the solar science, astronomy, mathematics, and technology. The movie in 2017, especially, may also have important science impact because of the uniqueness of the corona as seen under eclipse conditions. In this presentation we will describe our smartphone application development (see the "Transit of Venus" app for a role model here). We will also summarize data acquisition via both the app and more traditional web interfaces. Although for the Coral Sea eclipse event we don't expect to have a movie product by the time of the AGU, for the 2017 event we do intend to assemble the heterogenous data into beautiful movies within a short space of time after the eclipse. These movies may have relatively low resolution but would extend to the base of the corona. We encourage participation in the 2012 observations, noting that no total eclipse, prior to 2017, will occur in a region with good infrastructure

  4. Total Solar Eclipse of 1999 August 11

    NASA Technical Reports Server (NTRS)

    Espenak, Fred; Anderson, Jay

    1997-01-01

    On 1999 August 11, a total eclipse of the Sun will be visible from within a narrow corridor which traverses the Eastern Hemisphere. The path of the Moon's umbral shadow begins in the Atlantic and crosses central Europe, the Middle East, and India, where it ends at sunset in the Bay of Bengal. A partial eclipse will be seen within the much broader path of the Moon's penumbral shadow, which includes northeastern North America, all of Europe, northern Africa, and the western half of Asia. Detailed predictions for this event are presented and include besselian elements, geographic coordinates of the path of totality, physical ephemeris of the umbra, topocentric limb profile corrections, local circumstances for approximately 1400 cities, maps of the eclipse path, weather prospects, the lunar limb profile, and the sky during totality. Tips and suggestions are also given on how to safely view and photograph the eclipse.

  5. HF Band Observations and Modeling of the 2017 Eclipse

    NASA Astrophysics Data System (ADS)

    Earle, G. D.; Kordella, L.; Han, X.; Moses, M. L.; Sweeney, D.; McGwier, R. W.; Lloyd, W.; Ruohoniemi, J. M.

    2017-12-01

    A nationwide network of observatories has been created to study the effects of the 2017 eclipse on the F-region of the ionosphere. These include the SuperDARN HF radars in Oregon and Kansas, software defined radios in Oregon, Kansas, and South Carolina, and scintillation receivers placed northward of the central eclipse line across the continent. In this talk we will present data obtained by these systems during the eclipse, and interpret these data using a ray-tracing numerical code in conjunction with the SAMI-3 first principles model. Comparisons to results from the CORS network of GPS-TEC receivers will be made, and the F-region density and altitude perturbations observed during the eclipse will be contrasted with ionosonde data from an eclipse that occurred over the United Kingdom in 1999.

  6. Preparing a Nation for the Eclipse of a Generation -

    NASA Astrophysics Data System (ADS)

    Speck, Angela; Habbal, Shadia; Tresch Fienberg, Richard; Kentrianakis, Michael; Fraknoi, Andrew; Nordgren, Tyler; Penn, Matthew; Pasachoff, Jay M.; Bakich, Michael; Winter, Henry; Gay, Pamela; Motta, Mario

    2018-01-01

    On August 21st 2017, there was a total solar eclipse visible from a vast swath of the US.In preparation for that event, the American Astronomical society created a taskforce charged with planning for the eclipse for the entire nation. The preparations included interfacing with the public, the media, non-profit organizations and governmental organizations. Preliminary data suggests that nearly 90% of American adults watched the eclipse either directly or via live streams. Moreover, there were no major problems associated with the event, in spite of valiant attempts from, e.g. imprope solar viewing materials. The eclipse offered opportunities for many scientific experiments within and ebyond astronomy. Here we present on the work of the taskforce, and the lessons learned as well as lesser known science experiments undertaken during the eclipse.

  7. Selling the Great American Eclipse: An Education and Public Outreach Retrospective

    NASA Astrophysics Data System (ADS)

    Nordgren, T.

    2017-12-01

    The August 21, 2017 total solar eclipse was the single largest public scientific outreach event of the last several decades. The astronomical community, from organizations like to the American Astronomical Society, to government agencies such as NASA, to the nation-wide amateur astronomy community all worked to raise awareness of this unique event that would be visible to every single inhabitant of the United States. This outreach, like the event itself, was unique in requiring education on not just the science of the event, but the societal nature as well. This included such variety of subjects as: 1) eye safety for millions of individuals, 2) the importance of traveling to totality, 3) transportation issues over mass travel to regions in totality, 3) lodging, food, and logistics information for communities in totality, 4) governmental emergency response, and much more. I interview a number of communities, city managers, event planners, and national park rangers after the eclipse to identify what were the most important education and outreach information they received leading up to the event to assess what we in the astronomical community did that was most effective and what could have been done better in retrospect. In particular, I look at the use of the solar eclipse "travel poster" campaign I designed for event organizers, chambers of commerce, universities, and national and state parks in the four years leading up to the eclipse. How were they used and were they effective in raising the public's awareness of community events across the country? The lessons learned will be important for planning for the next eclipse that touches the U.S. in less than seven years from now on April 8, 2024.

  8. Total Eclipse of the Ballpark: Connecting Space and Sports

    NASA Astrophysics Data System (ADS)

    Wasser, Molly; Petro, Noah; Jones, Andrea; Bleacher, Lora; Keller, John; Wes Patterson, G.

    2018-01-01

    The anticipation and excitement surrounding the total solar eclipse of 2017 provided astronomy educators with an incredible platform to share space science with huge audiences. The Public Engagement Team for NASA’s Lunar Reconnaissance Orbiter (LRO) took advantage of this opportunity to share lunar science with the public by highlighting the often-overlooked central player in the eclipse – the Moon. As the sole planetary science representatives on NASA’s Science Mission Directorate eclipse leadership team, the LRO team had limited resources to conduct national public outreach. In order to increase our reach, we found success in partnerships.In early 2017, we began working with Minor League Baseball (MiLB) teams across the path of totality on August eclipse events. These partnerships proved fruitful for both parties. While MiLB is a national organization, each team is deeply rooted in its community. This proved essential as each of our four main MiLB partners handled event logistics, provided facilities, connected NASA Subject Matter Experts (SMEs) with local media, and drew in captive crowds. With this tactic, a handful of NASA representatives were able to reach nearly 30,000 people. In turn, LRO provided engaging educational content relevant to the context, SMEs to guide the eclipse viewing experience, eclipse glasses, and safety information. Our participation drew in an audience who would not typically attend baseball games while we were able to reach individuals who would not normally attend a science event. In addition, the eclipse inspired one team, the Salem-Keizer Volcanoes from Salem, OR, to make baseball history by holding the first ever eclipse delay in professional sports.In this talk, we will present on the benefits of the partnership, offer lessons learned, and suggest ways to get involved for the 2024 eclipse – and all the baseball seasons in between.

  9. Eclipse program F-106 aircraft in flight, front view

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Shot of the QF-106 aircraft in flight with the landing gear deployed. In 1997 and 1998, the Dryden Flight Research Center at Edwards, California, supported and hosted a Kelly Space & Technology, Inc. project called Eclipse, which sought to demonstrate the feasibility of a reusable tow-launch vehicle concept. The project goal was to successfully tow, inflight, a modified QF-106 delta-wing aircraft with an Air Force C-141A transport aircraft. This would demonstrate the possibility of towing and launching an actual launch vehicle from behind a tow plane. Dryden was the responsible test organization and had flight safety responsibility for the Eclipse project. Dryden provided engineering, instrumentation, simulation, modification, maintenance, range support, and research pilots for the test program. The Air Force Flight Test Center (AFFTC), Edwards, California, supplied the C-141A transport aircraft and crew and configured the aircraft as needed for the tests. The AFFTC also provided the concept and detail design and analysis as well as hardware for the tow system and QF-106 modifications. Dryden performed the modifications to convert the QF-106 drone into the piloted EXD-01 (Eclipse eXperimental Demonstrator-01) experimental aircraft. Kelly Space & Technology hoped to use the results gleaned from the tow test in developing a series of low-cost, reusable launch vehicles. These tests demonstrated the validity of towing a delta-wing aircraft having high wing loading, validated the tow simulation model, and demonstrated various operational procedures, such as ground processing of in-flight maneuvers and emergency abort scenarios.

  10. Countdown to the Great American Eclipse

    ERIC Educational Resources Information Center

    Fulco, Charles

    2017-01-01

    The Great American Total Solar Eclipse (TSE2017) will occur on August 21 this year--the first total solar eclipse in the continental United States since 1979. For many reasons, this is a scientific and educational milestone event of the highest magnitude that should not be missed by any teacher and student whether or not their school is in session…

  11. 2017 Total Solar Eclipse - ISS Transit

    NASA Image and Video Library

    2017-08-21

    This composite image, made from seven frames, shows the International Space Station, with a crew of six onboard, as it transits the Sun at roughly five miles per second during a partial solar eclipse, Monday, Aug. 21, 2017 near Banner, Wyoming. Onboard as part of Expedition 52 are: NASA astronauts Peggy Whitson, Jack Fischer, and Randy Bresnik; Russian cosmonauts Fyodor Yurchikhin and Sergey Ryazanskiy; and ESA (European Space Agency) astronaut Paolo Nespoli. A total solar eclipse swept across a narrow portion of the contiguous United States from Lincoln Beach, Oregon to Charleston, South Carolina. A partial solar eclipse was visible across the entire North American continent along with parts of South America, Africa, and Europe. Photo Credit: (NASA/Joel Kowsky)

  12. 2017 Total Solar Eclipse - ISS Transit

    NASA Image and Video Library

    2017-08-21

    The International Space Station, with a crew of six onboard, is seen in silhouette as it transits the Sun at roughly five miles per second during a partial solar eclipse, Monday, Aug. 21, 2017 from Ross Lake, Northern Cascades National Park, Washington. Onboard as part of Expedition 52 are: NASA astronauts Peggy Whitson, Jack Fischer, and Randy Bresnik; Russian cosmonauts Fyodor Yurchikhin and Sergey Ryazanskiy; and ESA (European Space Agency) astronaut Paolo Nespoli. A total solar eclipse swept across a narrow portion of the contiguous United States from Lincoln Beach, Oregon to Charleston, South Carolina. A partial solar eclipse was visible across the entire North American continent along with parts of South America, Africa, and Europe. Photo Credit: (NASA/Bill Ingalls)

  13. 2017 Total Solar Eclipse - ISS Transit

    NASA Image and Video Library

    2017-08-21

    This composite image, made from 4 frames, shows the International Space Station, with a crew of six onboard, as it transits the Sun at roughly five miles per second during a partial solar eclipse, Monday, Aug. 21, 2017 from , Northern Cascades National Park in Washington. Onboard as part of Expedition 52 are: NASA astronauts Peggy Whitson, Jack Fischer, and Randy Bresnik; Russian cosmonauts Fyodor Yurchikhin and Sergey Ryazanskiy; and ESA (European Space Agency) astronaut Paolo Nespoli. A total solar eclipse swept across a narrow portion of the contiguous United States from Lincoln Beach, Oregon to Charleston, South Carolina. A partial solar eclipse was visible across the entire North American continent along with parts of South America, Africa, and Europe. Photo Credit: (NASA/Bill Ingalls)

  14. Public education in developing countries on the occasions of eclipses

    NASA Astrophysics Data System (ADS)

    Pasachoff, Jay M.

    Total solar eclipses will cross southern Africa on June 21, 2001, and on December 4, 2002. Most of Africa will see partial phases. The total phase of the 2001 eclipse will be visible from parts of Angola, Zambia, Zimbabwe, Mozambique and Madagascar. The total phase of the 2002 eclipse will be visible from parts of Angola, Botswana, Zimbabwe, South Africa and Mozambique. Public education must be undertaken to tell the people how to look at the eclipse safely. We can take advantage of having the attention of the people and of news media to teach about not only eclipses but also the rest of astronomy. I am Chair of a "Public Education at Eclipses" subcommission of IAU Commission 46 on the Teaching of Astronomy, and we are able to advise educators and others about materials, procedures and information releases.

  15. The 1982 ultraviolet eclipse of the symbiotic binary AR Pav

    NASA Technical Reports Server (NTRS)

    Hutchings, J. B.; Cowley, A. P.; Ake, T. B.; Imhoff, C. L.

    1983-01-01

    Observations with the International Ultraviolet Explorer (IUE) of the symbiotic binary AR Pav through its 1982 eclipse show that the hot star is not eclipsed. The hot star is associated with an extended region of continuum emission which is partially eclipsed. The eclipsed radiation is hotter near to its center, with a maximum temperature of about 9000 K. The uneclipsed flux is hotter than this. UV emission lines are not measurably eclipsed and presumably arise in a much larger region than the continuum. These data provide new constraints on models of the system but also are apparently in contradiction to those based on ground-based data.

  16. The Great American Eclipse Glasses Debacle of 2017

    NASA Astrophysics Data System (ADS)

    Tresch Fienberg, Richard; AAS Solar Eclipse Task Force

    2018-01-01

    In 2014, looking ahead to the “Great American” solar eclipse of 21 August 2017, the American Astronomical Society established the AAS Solar Eclipse Task Force to help prepare the public for a safe and enjoyable experience. We worked with NASA and several associations of eye-care professionals to come up a safety message that we could all stand behind. The gist of it was that it is perfectly safe to view totality without protection, but when any part of the Sun’s bright face is exposed, you must view through eclipse glasses or handheld viewers that meet the ISO 12312-2 international safety standard for filters for direct viewing of the Sun. We compiled a list of manufacturers whose products we knew to meet the standard (because we examined their test data) and posted it on our website. These manufacturers were all based in the US or Europe. A few weeks before the eclipse, reports surfaced of viewers purchased on Amazon.com labeled “Made in China” or that were obvious knock-offs of US manufacturers’ products. Amazon responded by suspending virtually all sales of eclipse viewers and recalling many of units already sold and shipped. Millions of people who’d bought eclipse glasses online, whether from legitimate sources or from bad actors, were unsure whether they could trust their purchases. We had to change our safety messaging: it was no longer sufficient to tell people to look for the ISO 12312-2 label, because that was being printed on Chinese-made glasses that hadn’t actually been shown to meet the standard. Instead, the only way to know that you had safe viewers was to know that you got them from a legitimate source — which meant we had to expand the list on our website to include every legitimate seller we could identify. Doing so required a monumental effort under intense time pressure. Thankfully there were few reports of eye injuries following the eclipse, but apparently many people who otherwise would have viewed the eclipse chose to skip

  17. Research on the Solar Eclipse Records in the Wuxingzhi of Both {Han} Dynasties

    NASA Astrophysics Data System (ADS)

    Li, Y.

    2015-09-01

    In this paper, we investigate the paper Lianghan Rishi Kao (inspect the solar-eclipse records in Both {Han} dynasties) written by {Zhu Wenxin} when compared the solar-eclipse records with those in the book Zhongguo Gudai Tianxiang Jilu Zong ji (collection of Chinese ancient astronomical records), and find 38 (61) records with the same dates in Western (Eastern) {Han} dynasty, equal to 70% (85%) of total. Our results have 42 (61) with the same dates in Western (Eastern) {Han} dynasty as just 78% (85%) of the total. There are totally 126 solar-eclipse records in the Wuxingzhi of both {Han} Dynasties. We confirm that there are 21 no occurred, 7 invisible in the capital then, 9 occurred before sunrise, 1 after sunset, and the left 88 are seen, occupying 70% as usually occurred in the capital area. With the help of our transformation platform as from Chinese ancient 60-day-cycle style dates to Gregorian calendar dates, we check the date records of solar eclipses in the Wuxingzhi of both {Han} dynasties, and then review the accuracy of the calendar. The standard errors of month and day are respectively 0.31 month (0.17 month) and 0.97 day (0.74 day) in the Western (Eastern) {Han} dynasty. At the same time, the standard errors of solar location of the records are determined, they are 11.08° (6.63°) in Western (Eastern) {Han} dynasty, and after excluding the possible misrecords the accuracy changes to 9.30° (3.59°). If the Juxing (key star of this constellation) was the same in both {Han} dynasties, the average value of observation error of solar location in Eastern {Han} dynasty is 2.8°, far better than 8.2° in Western {Han} dynasty. Otherwise, they most likely appear in some constellations with larger deviation. We try to determine the Δ T (ET-UT) value of solar-eclipse records with the magnitude descriptions, and at the same time, it is concluded that the magnitude of Ji (total eclipse) is 0.969-1.0, Jijin (the sun is covered almost all) is 0.829-0.985, and

  18. Earth Eclipses the Sun

    NASA Image and Video Library

    2017-02-21

    Several times a day for a few days the Earth completely blocked the Sun for about an hour due to NASA's Solar Dynamics Observatory's orbital path (Feb. 15, 2017). The edge of the Earth is not crisp, but kind of fuzzy due to Earth's atmosphere. This frame from a video shows the ending of one such eclipse over -- just seven minutes. The sun is shown in a wavelength of extreme ultraviolet light. These eclipses re-occur about every six months. The Moon blocks SDO's view of the sun on occasion as well. Movies are available at http://photojournal.jpl.nasa.gov/catalog/PIA21461

  19. Eclipse SteerTech liquid lenslet beam steering technology

    NASA Astrophysics Data System (ADS)

    Westfall, Raymond T.; Rogers, Stanley; Shannon, Kenneth C., III

    2007-09-01

    Eclipse SteerTech TM transmissive fluid state electrowetting technology has successfully demonstrated the ability to control the shape and position of a fluid lenslet. In its final form, the technology will incorporate a dual fluid lenslet approach capable of operating in extremely high acceleration environments. The beam steering system works on the principle of electro-wetting. A substrate is covered with a closely spaced array of, independently addressable, transparent, electrically conductive pixels utilizing Eclipse's proprietary EclipseTEC TM technology. By activating and deactivating selected EclipseTEC TM pixels in the proper sequence, the shape and position of fluid lenslets or arrays of lenslets can be dynamically changed at will. The position and shape of individual fluid lenslets may be accurately controlled on any flat, simply curved, or complex curved, transparent or reflective surface. The smaller the pixels the better control of the position and shape of the fluid lenslets. Information on the successful testing of the Eclipse SteerTech TM lenslet and discussion of its use in a de-centered lenslet array will be presented.

  20. [Development of a Compared Software for Automatically Generated DVH in Eclipse TPS].

    PubMed

    Xie, Zhao; Luo, Kelin; Zou, Lian; Hu, Jinyou

    2016-03-01

    This study is to automatically calculate the dose volume histogram(DVH) for the treatment plan, then to compare it with requirements of doctor's prescriptions. The scripting language Autohotkey and programming language C# were used to develop a compared software for automatically generated DVH in Eclipse TPS. This software is named Show Dose Volume Histogram (ShowDVH), which is composed of prescription documents generation, operation functions of DVH, software visualization and DVH compared report generation. Ten cases in different cancers have been separately selected, in Eclipse TPS 11.0 ShowDVH could not only automatically generate DVH reports but also accurately determine whether treatment plans meet the requirements of doctor’s prescriptions, then reports gave direction for setting optimization parameters of intensity modulated radiated therapy. The ShowDVH is an user-friendly and powerful software, and can automatically generated compared DVH reports fast in Eclipse TPS 11.0. With the help of ShowDVH, it greatly saves plan designing time and improves working efficiency of radiation therapy physicists.

  1. High-speed photometry of the eclipsing dwarf nova OY Carinae

    NASA Technical Reports Server (NTRS)

    Cook, M. C.

    1985-01-01

    High-speed photometry of the eclipsing dwarf nova OY Car in the quiescent state is presented. OY Car becomes highly reddened during eclipse, with minimum flux colours inconsistent with optically thick emission in the U and B bandpasses. Mass ratios in the range 6.5 to 12 are required to reconcile the eclipse structure with theoretical gas stream trajectories. Primary eclipse timings reveal a significant decrease in the orbital period and the duration of primary eclipse indicates the presence of a luminous ring about the white dwarf. The hotspot eclipse reveals a hotspot which is elongated along the rim of the accretion disc, with optical emission being non-uniformly distributed along the rim. The location of the hotspot in the accretion disc implies a disc radius larger than that of an inviscid disc, with variation in the position of the hotspot being consistent with a fixed stream trajectory.

  2. Effects of vernal equinox solar eclipse on temperature and wind direction in Switzerland

    NASA Astrophysics Data System (ADS)

    Eugster, Werner; Emmel, Carmen; Wolf, Sebastian; Buchmann, Nina; McFadden, Joseph P.; Whiteman, Charles David

    2017-12-01

    The vernal equinox total solar eclipse of 20 March 2015 produced a maximum occultation of 65.8-70.1 % over Switzerland during the morning hours (09:22 to 11:48 CET). Skies were generally clear over the Swiss Alps due to a persistent high-pressure band between the UK and Russia associated with a rather weak pressure gradient over the continent. To assess the effects of penumbral shading on near-surface meteorology across Switzerland, air temperature data measured at 10 min intervals at 184 MeteoSwiss weather stations were used. Wind speed and direction data were available from 165 of these stations. Additionally, six Swiss FluxNet eddy covariance flux (ECF) sites provided turbulent measurements at 20 Hz resolution. During maximum occultation, the temperature drop was up to 5.8 K at a mountain site where cold air can pool in a topographic depression. The bootstrapped average of the maximum temperature drops of all 184 MeteoSwiss sites during the solar eclipse was 1.51 ± 0.02 K (mean ± SE). A detailed comparison with literature values since 1834 showed a temperature decrease of 2.6 ± 1.7 K (average of all reports), with extreme values up to 11 K. On fair weather days under weak larger-scale pressure gradients, local thermo-topographic wind systems develop that are driven by small-scale pressure and temperature gradients. At one ECF site, the penumbral shading delayed the morning transition from down-valley to up-valley wind conditions. At another site, it prevented this transition from occurring at all. Data from the 165 MeteoSwiss sites measuring wind direction did not show a consistent pattern of wind direction response to the passing of the penumbral shadow. These results suggest that the local topographic setting had an important influence on the temperature drop and the wind flow patterns during the eclipse. A significant cyclonic effect of the passing penumbral shadow was found in the elevation range ≈ 1700-2700 m a. s. l., but

  3. Coordinated weather balloon solar radiation measurements during a solar eclipse.

    PubMed

    Harrison, R G; Marlton, G J; Williams, P D; Nicoll, K A

    2016-09-28

    Solar eclipses provide a rapidly changing solar radiation environment. These changes can be studied using simple photodiode sensors, if the radiation reaching the sensors is unaffected by cloud. Transporting the sensors aloft using standard meteorological instrument packages modified to carry extra sensors, provides one promising but hitherto unexploited possibility for making solar eclipse radiation measurements. For the 20 March 2015 solar eclipse, a coordinated campaign of balloon-carried solar radiation measurements was undertaken from Reading (51.44°N, 0.94°W), Lerwick (60.15°N, 1.13°W) and Reykjavik (64.13°N, 21.90°W), straddling the path of the eclipse. The balloons reached sufficient altitude at the eclipse time for eclipse-induced variations in solar radiation and solar limb darkening to be measured above cloud. Because the sensor platforms were free to swing, techniques have been evaluated to correct the measurements for their changing orientation. In the swing-averaged technique, the mean value across a set of swings was used to approximate the radiation falling on a horizontal surface; in the swing-maximum technique, the direct beam was estimated by assuming that the maximum solar radiation during a swing occurs when the photodiode sensing surface becomes normal to the direction of the solar beam. Both approaches, essentially independent, give values that agree with theoretical expectations for the eclipse-induced radiation changes.This article is part of the themed issue 'Atmospheric effects of solar eclipses stimulated by the 2015 UK eclipse'. © 2016 The Authors.

  4. Eclipsing Binaries From the CSTAR Project at Dome A, Antarctica

    NASA Astrophysics Data System (ADS)

    Yang, Ming; Zhang, Hui; Wang, Songhu; Zhou, Ji-Lin; Zhou, Xu; Wang, Lingzhi; Wang, Lifan; Wittenmyer, R. A.; Liu, Hui-Gen; Meng, Zeyang; Ashley, M. C. B.; Storey, J. W. V.; Bayliss, D.; Tinney, Chris; Wang, Ying; Wu, Donghong; Liang, Ensi; Yu, Zhouyi; Fan, Zhou; Feng, Long-Long; Gong, Xuefei; Lawrence, J. S.; Liu, Qiang; Luong-Van, D. M.; Ma, Jun; Wu, Zhenyu; Yan, Jun; Yang, Huigen; Yang, Ji; Yuan, Xiangyan; Zhang, Tianmeng; Zhu, Zhenxi; Zou, Hu

    2015-04-01

    The Chinese Small Telescope ARray (CSTAR) has observed an area around the Celestial South Pole at Dome A since 2008. About 20,000 light curves in the i band were obtained during the observation season lasting from 2008 March to July. The photometric precision achieves about 4 mmag at i = 7.5 and 20 mmag at i = 12 within a 30 s exposure time. These light curves are analyzed using Lomb-Scargle, Phase Dispersion Minimization, and Box Least Squares methods to search for periodic signals. False positives may appear as a variable signature caused by contaminating stars and the observation mode of CSTAR. Therefore, the period and position of each variable candidate are checked to eliminate false positives. Eclipsing binaries are removed by visual inspection, frequency spectrum analysis, and a locally linear embedding technique. We identify 53 eclipsing binaries in the field of view of CSTAR, containing 24 detached binaries, 8 semi-detached binaries, 18 contact binaries, and 3 ellipsoidal variables. To derive the parameters of these binaries, we use the Eclipsing Binaries via Artificial Intelligence method. The primary and secondary eclipse timing variations (ETVs) for semi-detached and contact systems are analyzed. Correlated primary and secondary ETVs confirmed by false alarm tests may indicate an unseen perturbing companion. Through ETV analysis, we identify two triple systems (CSTAR J084612.64-883342.9 and CSTAR J220502.55-895206.7). The orbital parameters of the third body in CSTAR J220502.55-895206.7 are derived using a simple dynamical model.

  5. Eclipse Megamovie 2017: A Citizen Science Project

    NASA Astrophysics Data System (ADS)

    Johnson, C.; Koh, J.; Konerding, D.; Peticolas, L. M.; Hudson, H. S.; Martinez Oliveros, J. C.; Zevin, D.

    2017-12-01

    The 2017 total solar eclipse presents an amazing opportunity for education and science outreach due to the breadth and reach of this astronomical event. The Eclipse Megamovie project looks to create organize a citizen science effort to capture images of the eclipse as it crosses the US and stitch these photos together into a continuous look at the corona. A collaboration between Google, UC Berkeley, and many other universities and amateur astronomy networks, this project looks to leverage the different strenghts of these organizations and capitalize on this rare outreach opportunity. We're excited to present the results of the project and a review of how things went.

  6. The 1982-1984 Eclipse of Epsilon Aurigae

    NASA Technical Reports Server (NTRS)

    Stencel, R. E. (Editor)

    1985-01-01

    A workshop proceedings concerned with the new data collected during the 1982-1984 eclipse period of the 27-year system Epsilon Aurigae is presented. This binary star has been a classic problem in astrophysics because the opaque eclipsing object is nonstellar, and probably disk shaped. Invited papers concerning the history of the system, optical, infrared and ultraviolet photometry, optical polarimetry and ultraviolet spectroscopy are included. An invited paper concerning comprehensive theoretical interpretation in the context of stellar evolution also is included. The information collected herein is unparalleled in scope and will remain a standard reference until the next eclipse cycle in the year 2009 A.D., in all probability.

  7. Paper Moon: Simulating a Total Solar Eclipse

    ERIC Educational Resources Information Center

    Madden, Sean P.; Downing, James P.; Comstock, Jocelyne M.

    2006-01-01

    This article describes a classroom activity in which a solar eclipse is simulated and a mathematical model is developed to explain the data. Students use manipulative devices and graphing calculators to carry out the experiment and then compare their results to those collected in Koolymilka, Australia, during the 2002 eclipse.

  8. Suzaku Observation of the Dwarf Nova V893 Scorpii: The Discovery of a Partial X-Ray Eclipse

    NASA Technical Reports Server (NTRS)

    Mukai, Koji; Zietsman, E.; Still, M.

    2008-01-01

    V893 Sco is an eclipsing dwarf nova that had attracted little attention from X-ray astronomers until it was proposed as the identification of an RXTE all-sky slew survey (XSS) source. Here we report on the po inted X-ray observations of this object using Suzaku. We confirm V893 Sco to be X-ray bright, whose spectrum is highly absorbed for a dwar f nova. We have also discovered a partial X-ray eclipse in V893 Sco. This is the first time that a partial eclipse is seen in Xray light c urves of a dwarf nova. We have successfully modeled the gross features of the optical and X-ray eclipse light curves using a boundary layer geometry of the X-ray emission region. Future observations may lead to confirmation of this basic picture, and allow us to place tight co nstraints on the size of the X-ray emission region. The partial X-ray eclipse therefore should make V893 Sco a key object in understanding the physics of accretion in quiescent dwarf nova.

  9. Dynamics of Coronal Structures Captured During the 2012 and 2013 Total Solar Eclipses

    NASA Astrophysics Data System (ADS)

    Alzate, N.; Habbal, S. R.; Druckmuller, M.

    2017-12-01

    White light eclipse images taken during total solar eclipses provide a very high dynamic range spanning tens of solar radii starting from the solar surface. They capture the instantaneous state of the corona, including dynamic events. We present observations of the 2012 November 13 and 2013 November 3 total solar eclipses, taken by Constantinos Emmanouilidis, in which we captured high latitude tethered prominences accompanied by CMEs, as well as several `atypical' large scale structures, spanning a few solar radii above the solar surface. By complementing the eclipse observations with co-temporaneous SDO/AIA, STEREO/EUVI and SOHO/LASCO observations, we show how the shape of the atypical structures outlines the shape of faint CME shock fronts, driven by flaring activities. The tethered prominences were imaged from their anchor at the solar surface out to several solar radii. The SDO/AIA 30.4, 17.1 and 19.3 nm emission clearly show how a direct link between the cool (104 - 105 K) filamentary emission from prominence material, and the filamentary structures emitting at coronal temperatures (> 106 K), is unmistakably present. The observed survival of these tethered systems out to the field of view of LASCO C3, establishes the likely origin of counter-streaming electrons associated with CMEs observed in interplanetary space (ICMEs). They also provide new insights for CME-initiation models associated with prominence eruptions. Our work highlights the uniqueness of eclipse observations in identifying the impact of transit events on large-scale coronal structures.

  10. Total Eclipse

    ERIC Educational Resources Information Center

    Schatz, Dennis; Fraknoi, Andrew

    2017-01-01

    This summer, on August 21, 500 million people across North America will experience one of the most beautiful astronomical phenomena: an eclipse of the Sun. It will be a "must teach" moment, when all students will want to know the "what, when, and why" of the event. In addition, many high school science teachers are likely to be…

  11. Coronal Dynamics at Recent Total Solar Eclipses

    NASA Astrophysics Data System (ADS)

    Pasachoff, J. M.; Lu, M.; Davis, A. B.; Demianski, M.; Rusin, V.; Saniga, M.; Seaton, D. B.; Lucas, R.; Babcock, B. A.; Dantowitz, R.; Gaintatzis, P.; Seeger, C. H.; Malamut, C.; Steele, A.

    2014-12-01

    Our composite images of the solar corona based on extensive imaging at the total solar eclipses of 2010 (Easter Island), 2012 (Australia), and 2013 (Gabon) reveal several coronal mass ejections and other changes in coronal streamers and in polar plumes. Our resultant spatial resolution is finer than that available in imaging from spacecraft, including that from SOHO/LASCO or STEREO. We trace the eruptions back to their footpoints on the sun using imaging from SDO and SWAP, and follow them upwards through the corona, measuring velocities. The high-resolution computer compositing by Miloslav Druckmüller and Hana Druckmüllerová (2010 and 2013) and Pavlos Gaintatzis (2012) allows comparison of our images with those taken at intervals of minutes or hours along the totality path. Williams College's 2013 eclipse expedition was supported in part by grant 9327-13 from National Geographic Society/Committee for Research and Exploration. Our work on the 2012 eclipse is supported in part by grant AGS-1047726 from Solar Terrestrial Research/NSF AGS. V.R. and M.S. were partially supported by the VEGA grant agency project 2/0098/10 and 2/0003/13 (Slovak Academy of Sciences) and Grant 0139-12 from NG/CRE, and Hana Druckmüllerová by grant 205/09/1469 of the Czech Science Foundation. M.L. was supported by Sigma Xi. C.M. was a Keck Northeast Astronomy Consortium Summer Fellow, supported at Williams College by REU/NSF grant AST-1005024. Partial support was provided by U.S. Department of Defense's ASSURE program. J.M.P. thanks Caltech's Planetary Sciences Department for hospitality. Support for D.B.S. and SWAP came from PRODEX grant C90345 managed by ESA in collaboration with the Belgian Federal Science Policy Office (BELSPO) in support of the PROBA2/SWAP mission, and from the EC's Seventh Framework Programme (FP7/2007-2013) under grant 218816 (SOTERIA project, www.soteria-space.eu). SWAP is a project of the Centre Spatial de Liège and the Royal Observatory of Belgium funded by

  12. Surveying the IR corona during the 2017 solar eclipse

    NASA Astrophysics Data System (ADS)

    Bryans, P.; Hannigan, J. W.; Sewell, S. D.; Judge, P. G.

    2017-12-01

    The spectral emission of the infrared solar corona is the most promising direct diagnostic of the coronal magnetic field, and yet remains poorly measured. During the 2017 total solar eclipse, we will perform the first spectral survey of the IR corona using the NCAR Airborne Interferometer. This Fourier Transform Infrared Spectrometer is configured to observe the coronal spectrum from 1.5 to 5.5 microns at R 10,000 from a ground-based site. The location is atop Casper Mountain, Wyoming (42.73ºN, 106.32ºW, 2400 masl), 8 km from the center-line of totality. In this presentation, we will outline the need for such measurements, describe the instrument design and adaptation for the eclipse measurement, observation scheme, and present preliminary results. We will also discuss implications for observing infrared coronal lines from the ground, for example with the upcoming DKIST facility.

  13. Navigating the Path of Totality - Results and Lessons Learned from the 2017 Eclipse Broadcast, Webcast, Mobile App and Online Production

    NASA Astrophysics Data System (ADS)

    Semper, R.; Higdon, R.

    2017-12-01

    The 2017 total solar eclipse provided unique opportunity to provide public outreach about astronomy, heliophysics, and scientific discovery. The Navigating the Path of Totality project was designed to produce eclipse related educational resources including live video feeds and distribute them to museums, schools, libraries and the public through online and broadcast media. Using special telescope video camera setups, five feeds were produced including a live one hour English program and in parallel a live one hour Spanish program from Casper, WY with a cutaway to Madras, OR, complete (C1-C4) telescope only feeds from both Madras, OR and Casper, Wy, and a complete (C1-C4) telescope only feed with live musical sonification and accompaniment by the Kronos Quartet. Images from the live feeds were made available on the NASA Website, NASA TV, Exploratorium website, Exploratorium Solar Eclipse mobile app, local television and in museums, libraries and schools worldwide. Associated educational video material including images from the 2016 total eclipse from Micronesia was produced and disseminated. In this talk we will discuss the evaluation results including an examination of the effectiveness of the digital strategy of many mobile channels and mobile apps using different analytics including IBM Watson social media analytics services. We will also present the lessons learned from the project.

  14. 2017 Total Solar Eclipse - ISS Transit - (NHQ201708210203)

    NASA Image and Video Library

    2017-08-21

    2017 Total Solar Eclipse - ISS Transit - (NHQ201708210203) In this video captured at 1,500 frames per second with a high-speed camera, the International Space Station, with a crew of six onboard, is seen in silhouette as it transits the sun at roughly five miles per second during a partial solar eclipse, Monday, Aug. 21, 2017 near Banner, Wyoming. Onboard as part of Expedition 52 are: NASA astronauts Peggy Whitson, Jack Fischer, and Randy Bresnik; Russian cosmonauts Fyodor Yurchikhin and Sergey Ryazanskiy; and ESA (European Space Agency) astronaut Paolo Nespoli. A total solar eclipse swept across a narrow portion of the contiguous United States from Lincoln Beach, Oregon to Charleston, South Carolina. A partial solar eclipse was visible across the entire North American continent along with parts of South America, Africa, and Europe. Photo Credit: (NASA/Joel Kowsky)

  15. Satellite observations of surface temperature during the March 2015 total solar eclipse.

    PubMed

    Good, Elizabeth

    2016-09-28

    The behaviour of remotely sensed land surface temperatures (LSTs) from the spinning-enhanced visible and infrared imager (SEVIRI) during the total solar eclipse of 20 March 2015 is analysed over Europe. LST is found to drop by up to several degrees Celcius during the eclipse, with the minimum LST occurring just after the eclipse mid-point (median=+1.5 min). The drop in LST is typically larger than the drop in near-surface air temperatures reported elsewhere, and correlates with solar obscuration (r=-0.47; larger obscuration = larger LST drop), eclipse duration (r=-0.62; longer duration = larger LST drop) and time (r=+0.37; earlier eclipse = larger LST drop). Locally, the LST drop is also correlated with vegetation (up to r=+0.6), with smaller LST drops occurring over more vegetated surfaces. The LSTs at locations near the coast and at higher elevation are also less affected by the eclipse. This study covers the largest area and uses the most observations of eclipse-induced surface temperature drops to date, and is the first full characterization of satellite LST during an eclipse (known to the author). The methods described could be applied to Geostationary Operational Environmental Satellite (GOES) LST data over North America during the August 2017 total solar eclipse.This article is part of the themed issue 'Atmospheric effects of solar eclipses stimulated by the 2015 UK eclipse'. © 2016 The Author(s).

  16. The 2017 Solar Eclipse Community Impacts through Public Library Engagement

    NASA Astrophysics Data System (ADS)

    Dusenbery, P.; Holland, A.; LaConte, K.; Mosshammer, G.; Harold, J. B.; Fraknoi, A.; Schatz, D.; Duncan, D. K.

    2017-12-01

    More than two million pairs of eclipse glasses were distributed free through public libraries in the U.S. for the solar eclipse of the Sun taking place on August 21, 2017. About 7,000 organizations, including public library branches, bookmobiles, tribal libraries, library consortia, and state libraries took part in the celestial event of the century. Many organizations received a package of free safe-viewing glasses, plus a 24-page information booklet about eclipse viewing and suggested program ideas. An educational video was also produced on how best to do public outreach programs about the eclipse. The project was supported, in part, by the Gordon and Betty Moore Foundation, with additional help from Google, NASA, the Research Corporation, and the National Science Foundation (NSF). The program was managed through the Space Science Institute's National Center for Interactive Learning as part of its STAR Library Network (STAR_Net). Resources developed by STAR_Net for this event included an Eclipse Resource Center; a newsletter for participating libraries to learn about eclipses and how to implement an effective and safe eclipse program; eclipse program activities on its STEM Activity Clearinghouse; webinars; and connections to subject matter experts from NASA's and the American Astronomical Society's volunteer networks. This presentation will provide an overview of the extensive collaboration that made this program possible as well as highlight the national impact that public libraries made in their communities.

  17. Ionospheric response to the total solar eclipse in India on 22 July, 2009

    NASA Astrophysics Data System (ADS)

    Chauhan, Vishal; Agrawal, Shikah; Singh, O. P.; Singh, Birbal

    2010-05-01

    The variations in total electron content (TEC) and amplitude of the fixed frequency VLF transmitter signals (f =19.8 kHz, NWC, Australia) are studied at Agra (Geographic lat. 27.20N, long. 780E), India during the total solar eclipse of 22 July, 2009 which was longest seen in India ever since 18 August, 1968. The equipments used for the study are a dual frequency GPS receiver (GSV 4004V). The data for a period of fifteen days (±7 days from the date of the event) are analysed and it is found that the TEC decreased by about 30% from normal days during the total solar eclipse. The period of the data analysis is characterised by a low level of geomagnetic activity, hence the decrease in TEC s is unlikely to be influenced by geomagnetic disturbances. The results are interpreted in terms of depression in electron densities at all ionospheric heights and are consistent with those obtained by earlier workers during similar eclipse events.

  18. Observations of eclipses of UU Sge

    NASA Astrophysics Data System (ADS)

    Shimansky, V. V.; Borisov, N. V.; Bikmaev, I. F.; Shimanskaya, N. N.

    2012-06-01

    We have performed spectroscopy and photometry of eclipses of the pre-cataclysmic variable UUSge using the 6-m telescope of the Special AstrophysicalObservatory and the 1.5-mRussian-Turkish telescope. Our analysis of variations of the B- V and V- R color indices during the eclipses indicates that the temperature of the secondary is T eff,2 = 6000-6300 K. A similar value, T eff,2 = 6200 ± 200 K, follows from our comparison of the observed spectrum of UU Sge at the total eclipse phase and theoretical spectra of late-type stars. We identify 27 absorption lines of 11 chemical elements in the secondary's spectrum. Their abnormal intensities indicate possible high-velocity turbulent motions (up to ξ turb = 10.0 km/s) in the atmosphere of the star and the presence of hot gas above its surface.

  19. 2017 Total Solar Eclipse Science Briefing

    NASA Image and Video Library

    2017-06-21

    During a June 21 media briefing from the Newseum in Washington, representatives from NASA, other federal agencies, and science organizations discussed the opportunity for scientific study offered by the total solar eclipse that will cross the U.S. on August 21. Over the course of 100 minutes, 14 states across the United States will experience more than two minutes of darkness in the middle of the day. Additionally, a partial eclipse will be viewable across all of North America. The eclipse will provide a unique opportunity to study the sun, Earth, moon and their interaction because of the eclipse’s long path over land coast to coast. Scientists will be able to take ground-based and airborne observations over a period of an hour and a half to complement the wealth of data and images provided by space assets.

  20. A1540-53, an eclipsing X-ray binary pulsator

    NASA Technical Reports Server (NTRS)

    Becker, R. H.; Swank, J. H.; Boldt, E. A.; Holt, S. S.; Serlemitsos, P. J.; Pravdo, S. H.; Saba, J. R.

    1977-01-01

    An eclipsing X-ray binary pulsator consistent with the location of A1540-53 has been observed. The source pulse period was 528.93 + or - 0.10 s. The binary nature is confirmed by a Doppler curve for the pulsation period. The eclipse angle of 30.5 + or - 3 deg and the 4-hour transition to and from eclipse suggest an early-type giant or supergiant primary star.

  1. Lessons from Distributing Eclipse Glasses: Planning Ahead for April 2024

    NASA Astrophysics Data System (ADS)

    Bartlett, Jennifer Lynn; Wilson, Teresa; Chizek Frouard, Malynda R.; Phlips, Alan

    2018-01-01

    In preparation for the 2017 August 21 total solar eclipse across the continental United States, a multifaceted effort encouraged safe public observation of this spectacular event. However, we experienced mixed results distributing free ISO 12312-2 compliant eclipse glasses.On the positive side, we successfully dispensed several hundred in Virginia through in-school programs about the eclipse. We created a 2017-eclipse information sheet to accompany a safe-viewing handout. To facilitate sending glasses home in student backpacks, we wrapped each pair in a double-sided flyer and sealed the bundle in an individual envelope. We also passed out glasses during evening and weekend activities at a planetarium. Religious, business, and educational groups were all excited to receive them as were co-workers, family, and friends.On the negative side, planetarium staff declined to give eclipse glasses to students without a parent due to safety and liability concerns. Then, a day camp returned 200 pairs less than 72 hours before the event for the same reasons. However, we also received several requests from groups that had waited until too late to be accommodated easily.During the week before the eclipse, demand for eclipse glasses in New York, Michigan, Indiana, Illinois, Wisconsin, Minnesota, South Dakota, Nebraska, and Missouri was less than anticipated. While many people were well prepared, the recalls and reported counterfeiting made others suspicious. Concurrently, vendors were offering their remaining stock for $1–10 each.The experiences of the 2017 total solar eclipse, both good and bad, will not completely fade before preparations for 2024 begin. We look forward enthusiastically to sharing that event with as many people as possible and hope that the overall distribution of eclipse glasses goes more smoothly.We thank the AAS for providing 1,000+ of the eclipse glasses we shared, which were donated to them by Google to promote the Eclipse Megamovie project; Rainbow

  2. Spitzer Secondary Eclipses of HAT-P-13b

    NASA Astrophysics Data System (ADS)

    Hardy, Ryan A.; Harrington, J.; Hardin, M. R.; Madhusudhan, N.; Cubillos, P.; Blecic, J.; Bakos, G.; Hartman, J. D.

    2013-10-01

    HAT-P-13 b is a transiting hot Jupiter with a slightly eccentric orbit (e = 0.010) inhabiting a two-planet system. The two-planet arrangement provides an opportunity to probe the interior structure of HAT-P-13b. Under equilibrium-tide theory and confirmation that the apsides of planets b and c are in alignment, a measurement of the planet's eccentricity can be related to the planet's tidal Love number k2, which describes the central condensation of the planet's mass and its deformation under tidal effects. A measurement of k2 could constrain interior models of HAT-P-13b. HAT-P-13b's orbit is configured favorably for refinement of the eccentricity by secondary eclipse timing observations, which provide direct measurements of ecosω. In 2010, Spitzer observed two secondary eclipses of HAT-P-13b in the 3.6- and 4.5-μm IRAC bandpasses. We present secondary eclipse times and depths; joint models of the HAT-P-13 system that incorporate transit photometry and radial velocity data; and constraints on the atmospheric chemistry of HAT-P-13b that suggest solar-abundance composition without a thermal inversion. Spitzer is operated by the Jet Propulsion Laboratory, California Institute of Technology, under a contract with NASA, which provided support for this work. This work was supported in part by NASA Planetary Atmospheres Grant NNX13AF38G.

  3. Period changes of the sample of eclipsing binaries with active chromospheres

    NASA Astrophysics Data System (ADS)

    Jableka, D.; Zola, S.; Zakrzewski, B.; Szymanski, T.; Kuzmicz, A.; de Villiers, S. N.; Zejda, M.; Koziel-Wierzbowska, D.

    2012-11-01

    In this work we present results derived from analysis of the O-C behaviour of ten eclipsing binary systems: AR Lac, CG Cyg, HP Aur, MM Her, RS CVn, RT And, SV Cam, V471 Tau, WW Dra and CF Tuc. It was proved on the basis of moments of minima compiled from the literature and new ones determined from recent observations, that these binaries show long term (19-91 years) modulations of their orbital periods, clearly visible in their O-C diagrams. Two possible explanations for this effect are considered: (1) the light-travel time effect due to the presence of a third body orbiting the eclipsing systems; (2) the Applegate mechanism predicting period modulation by changes in the distribution of angular momentum as a star goes through its activity cycles. It was found that in the case of four systems the existence of a third star, orbiting the binary, is a more plausible explanation of observations.

  4. Constructing 'Black Sun': the Documentary Film of the 2012 Eclipses

    NASA Astrophysics Data System (ADS)

    Holbrook, Jarita

    2014-06-01

    2012 offered an opportunity that was not to be missed: two solar eclipses. Drs Alphonse Sterling and Hakeem Oluseyi began doing collaborative research during total solar eclipses in 2006 in Ghana. Since then they have continued to do eclipse observation when funds and whether permitted. As a filmmaker, the opportunity to film Sterling and Oluseyi during the 2012 eclipses in Tokyo and Cairns fulfilled the goal of showing the excitement of time-sensitive research, the lives of astrophysicists, and diversity within the astronomy community. As an astrophysicist who did not specialize in solar astrophysics, it was an opportunity for me both to learn and to solidify for the audience what we know about the sun and the importance of eclipse observation. Clips of the film will be included.

  5. Get Ready for the Great American Eclipse!

    ERIC Educational Resources Information Center

    Fulco, Charles

    2017-01-01

    This year marks 38 years since any part of the continental United States was darkened by the Moon's umbral shadow. During this "eclipse drought," no U.S. residents except those on Hawaii's Big Island in 1991 have had the opportunity to observe totality without traveling abroad. The 2017 Total Solar Eclipse (TSE2017, August 21, 2017) is…

  6. Books and Other Resources for Education about the August 21, 2017, Solar Eclipse

    NASA Astrophysics Data System (ADS)

    Pasachoff, Jay M.; Fraknoi, Andrew; Kentrianakis, Michael

    2017-06-01

    As part of our work to reach and educate the 300+ million Americans of all ages about observing the August 21 solar eclipse, especially by being outdoors in the path of totality but also for those who will see only partial phases, we have compiled annotated lists of books, pamphlets, travel guides, websites, and other information useful for teachers, students, and the general public and made them available on the web, at conferences, and through webinars. Our list includes new eclipse books by David Barron, Anthony Aveni, Frank Close, Tyler Nordgren, John Dvorak, Michael Bakich, and others. We list websites accessible to the general public including those of the International Astronomical Union Working Group on Eclipses (http://eclipses.info, which has links to all the sites listed below); the AAS Eclipse 2017 Task Force (http://eclipse2017.aas.org); NASA Heliophysics (http://eclipse.nasa.gov); Fred Espenak (the updated successor to his authoritative "NASA website": http://EclipseWise.com); Michael Zeiler (http://GreatAmericanEclipse.com); Xavier Jubier (http://xjubier.free.fr/en/site_pages/solar_eclipses/); Jay Anderson (meteorology: http://eclipsophile.com); NASA's Eyes (http://eyes.nasa.gov/eyes-on-eclipse.html and its related app); the Astronomical Society of the Pacific (http://www.astrosociety.org/eclipse); Dan McGlaun (http://eclipse2017.org/); Bill Kramer (http://eclipse-chasers.com). Specialized guides include Dennis Schatz and Andrew Fraknoi's Solar Science for teachers (from the National Science Teachers Association:http://www.nsta.org/publications/press/extras/files/solarscience/SolarScienceInsert.pdf), and a printing with expanded eclipse coverage of Jay Pasachoff's, Peterson Field Guide to the Stars and Planets (14th printing of the fourth edition, 2016: http://solarcorona.com).A version of our joint list is to be published in the July issue of the American Journal of Physics as a Resource Letter on Eclipses, adding to JMP's 2010, "Resource Letter SP

  7. Five Millennium Catalog of Lunar Eclipses: -1999 to +3000 (2000 BCE to 3000 CE)

    NASA Technical Reports Server (NTRS)

    Espenak, Fred; Meeus, Jean

    2009-01-01

    This catalog is a supplement to the "FiveMillenniumCanonofLunarEclipses." It includes additional information for each eclipse that could not be included in the original publication because of size limits. The data tabulated for each eclipse include the catalog number, canon plate number, calendar date, Terrestrial Dynamical Time of greatest eclipse, (Delta)T, lunation number, Saros number, eclipse type, Quincena Solar Eclipse parameter, gamma, penumbral and umbral eclipse magnitudes, durations of penumbral, partial and total eclipse phases, and geographic coordinates of greatest eclipse (latitude and longitude). The Canon and the Catalog both use the same solar and lunar ephemerides as well as the same values of (Delta)T. This 1-to-1 correspondence between them will enhance the value of each. The researcher may now search, evaluate, and compare eclipses graphically (Canon) or textually (Catalog).

  8. Solar Eclipse Engagement and Outreach in Madras and Warm Springs, Oregon

    NASA Astrophysics Data System (ADS)

    Kirk, M. S.; Pesnell, W. D.; Ahern, S.; Boyle, M.; Gonzales, T.; Leone, C.

    2017-12-01

    The Central Oregon towns of Madras and Warm Springs were in an ideal location to observe the total solar eclipse of 2017. In anticipation of this event, we embarked on a yearlong partnership to engage and excite these communities. We developed educational events for all students in the school district, grades K-12, as well as two evening keynote addresses during an eclipse week in May. This eclipse week provided resources, learning opportunities, and safety information for all students and families prior to the end of the school year. With the collaboration of graphic design students at Oregon State University, we produced static educational displays as an introduction to the Museum at Warm Springs' exhibit featuring eclipse art. The weekend before the eclipse, we gave away 15,000 pairs of solar viewing glasses to the local community and manned a science booth at the Oregon Solarfest to engage the arriving eclipse tourists. These efforts culminated on Monday, August 21st with tens of thousands of people viewing eclipse totality in Madras and Warm Springs.

  9. Outreach activities in anticipation of the 2016 solar eclipse in Sorong

    NASA Astrophysics Data System (ADS)

    Putra Raharja, Endra; Pramudya, Yudhiakto

    2016-11-01

    Sorong is located outside the narrow path of total solar eclipse on March 9th, 2016. The predicted obscuration of the sun was 94.2%. The public outreach to anticipate the solar eclipse was intended to educate students in junior and senior high school in Sorong Regency. Some of them are located in the remote area where the educational materials are difficult to find. The public outreach is unique, since it was run by the local person who is student of physics education. The student has both the ability to explain the solar eclipse phenomenon and able to adapt to knowledge level of students. The materials that were given to the schools are brochure and the eclipse glasses. Beside solar eclipse lectures in class, the pinhole workshop and observation practice were held. The limited materials and resources were faced during the public outreach. However, the enthusiasm was shown by the students and teachers. At least one of the schools held the solar eclipse observation on the day of the eclipse.

  10. A1540-53, an eclipsing X-ray binary pulsator

    NASA Technical Reports Server (NTRS)

    Becker, R. H.; Swank, J. H.; Boldt, E. A.; Holt, S. S.; Pravdo, S. H.; Saba, J. R.; Serlemitsos, P. J.

    1977-01-01

    An eclipsing X-ray binary pulsator consistent with the location of A1540-53 was observed. The source pulse period was 528.93 plus or minus 0.10 seconds. The binary nature is confirmed by a Doppler curve for the pulsation period. The eclipse angle of 30.5 deg plus or minus 3 deg and the 4 h transition to and from eclipse suggest an early type, giant or supergiant, primary star.

  11. Photometric Study of the Pulsating, Eclipsing Binary OO Dra

    NASA Astrophysics Data System (ADS)

    Zhang, X. B.; Deng, L. C.; Tian, J. F.; Wang, K.; Sun, J. J.; Liu, Q. L.; Xin, H. Q.; Zhou, Q.; Yan, Z. Z.; Luo, Z. Q.; Luo, C. Q.

    2014-12-01

    We present a comprehensive photometric study of the pulsating, eclipsing binary OO Dra. Simultaneous B- and V-band photometry of the star was carried out on 14 nights. A revised orbital period and a new ephemeris were derived from the data. The first photometric solution of the binary system and the physical parameters of the component stars are determined. They reveal that OO Dra could be a detached system with a less-massive secondary component nearly filling its Roche lobe. By subtracting the eclipsing light changes from the data, we obtained the intrinsic pulsating light curves of the hotter, massive primary component. A frequency analysis of the residual light yields two confident pulsation modes in both B- and V-band data with the dominant frequency detected at 41.865 c/d. A brief discussion concerning the evolutionary status and the pulsation nature of the binary system is finally given.

  12. UPLC-MS method for quantification of pterostilbene and its application to comparative study of bioavailability and tissue distribution in normal and Lewis lung carcinoma bearing mice.

    PubMed

    Deng, Li; Li, Yongzhi; Zhang, Xinshi; Chen, Bo; Deng, Yulin; Li, Yujuan

    2015-10-10

    A UPLC-MS method was developed for determination of pterostilbene (PTS) in plasma and tissues of mice. PTS was separated on Agilent Zorbax XDB-C18 column (50 × 2.1 mm, 1.8 μm) with gradient mobile phase at the flow rate of 0.2 ml/min. The detection was performed by negative ion electrospray ionization in multiple reaction monitoring mode. The linear calibration curve of PTS in mouse plasma and tissues ranged from 1.0 to 5000 and 0.50 to 500 ng/ml (r(2)>0.9979), respectively, with lowest limits of quantification (LLOQ) were between 0.5 and 2.0 ng/ml, respectively. The accuracy and precision of the assay were satisfactory. The validated method was applied to the study of bioavailability and tissue distribution of PTS in normal and Lewis lung carcinoma (LLC) bearing mice. The bioavailability of PTS (dose 14, 28 and 56 mg/kg) in normal mice were 11.9%, 13.9% and 26.4%, respectively; and the maximum level (82.1 ± 14.2 μg/g) was found in stomach (dose 28 mg/kg). The bioavailability, peak concentration (Cmax), time to peak concentration (Tmax) of PTS in LLC mice was increased compared with normal mice. The results indicated the UPLC-MS method is reliable and bioavailability and tissue distribution of PTS in normal and LLC mice were dramatically different. Copyright © 2015 Elsevier B.V. All rights reserved.

  13. Five Millennium Canon of Solar Eclipses: -1999 to +3000 (2000 BCE to 3000 CE)

    NASA Technical Reports Server (NTRS)

    Espenak, Fred; Meeus, Jean

    2006-01-01

    During 5,000-year period from -1999 to +3000 (2000BCE to 3000CE), Earth will experience 11,898 eclipses of the Sun. The statistical distribution of eclipse types for this interval is as follows: 4,200 partial eclipses, 3956 annular eclipses, 3173 total eclipses,and 569 hybrid eclipses. Detailed global maps for each of the 11,898 eclipses delineate the geographic regions of visibility for both the penumbral (partial) and umbral or antumbral (total, annular, or hybrid) phases of every event. Modern political borders are plotted to assist in the determination of eclipse visibility. The uncertainty in Earth's rotational period expressed in the parameter (delta)T and its impact on the geographic visibility of eclipses in the past and future is discussed.

  14. Coordinated weather balloon solar radiation measurements during a solar eclipse

    PubMed Central

    2016-01-01

    Solar eclipses provide a rapidly changing solar radiation environment. These changes can be studied using simple photodiode sensors, if the radiation reaching the sensors is unaffected by cloud. Transporting the sensors aloft using standard meteorological instrument packages modified to carry extra sensors, provides one promising but hitherto unexploited possibility for making solar eclipse radiation measurements. For the 20 March 2015 solar eclipse, a coordinated campaign of balloon-carried solar radiation measurements was undertaken from Reading (51.44°N, 0.94°W), Lerwick (60.15°N, 1.13°W) and Reykjavik (64.13°N, 21.90°W), straddling the path of the eclipse. The balloons reached sufficient altitude at the eclipse time for eclipse-induced variations in solar radiation and solar limb darkening to be measured above cloud. Because the sensor platforms were free to swing, techniques have been evaluated to correct the measurements for their changing orientation. In the swing-averaged technique, the mean value across a set of swings was used to approximate the radiation falling on a horizontal surface; in the swing-maximum technique, the direct beam was estimated by assuming that the maximum solar radiation during a swing occurs when the photodiode sensing surface becomes normal to the direction of the solar beam. Both approaches, essentially independent, give values that agree with theoretical expectations for the eclipse-induced radiation changes. This article is part of the themed issue ‘Atmospheric effects of solar eclipses stimulated by the 2015 UK eclipse’. PMID:27550757

  15. Investigations of a New Eclipsing Cataclysmic Variable HBHA 4705-03

    NASA Astrophysics Data System (ADS)

    Yakin, D. G.; Suleimanov, V. F.; Shimansky, V. V.; Vlasyuk, V. V.; Spiridonova, O. I.

    2013-01-01

    Results of photometric and spectroscopic investigations of the recently discovered eclipsing cataclysmic variable star HBHA 4705-03 are presented. The emission spectra of the system show broad hydrogen and helium emission lines. The bright spots with an approximately zero velocity components are found in the Doppler maps for the hydrogen and ionized helium lines. The disc structure is more prominent in the maps for the neutral helium lines. The masses of the components (MWD = 0.54 ± 0.10M⊙ and MRD = 0.45 ± 0.05 M⊙), and the orbit inclination (i = 71.°8 ± 0.°7) were estimated using the radial velocity light curve and the eclipse width. The modeling of the light curve allows us to evaluate the bright spot parameters and the mass accretion rate (M ≍ 2 ·1017 g s-1).

  16. Simulation of Ionospheric Response During Solar Eclipse Events

    NASA Astrophysics Data System (ADS)

    Kordella, L.; Earle, G. D.; Huba, J.

    2016-12-01

    Total solar eclipses are rare, short duration events that present interesting case studies of ionospheric behavior because the structure of the ionosphere is determined and stabilized by varying energies of solar radiation (Lyman alpha, X-ray, U.V., etc.). The ionospheric response to eclipse events is a source of scientific intrigue that has been studied in various capacities over the past 50 years. Unlike the daily terminator crossings, eclipses cause highly localized, steep gradients of ionization efficiency due to their comparatively small solar zenith angle. However, the corona remains present even at full obscuration, meaning that the energy reduction never falls to the levels seen at night. Previous eclipse studies performed by research groups in the US, UK, China and Russia have shown a range of effects, some counter-intuitive and others contradictory. In the shadowed region of an eclipse (i.e. umbra) it is logical to assume a reduction in ionization rates correlating with the reduction of incident solar radiation. Results have shown that even this straightforward hypothesis may not be true; effects on plasma distribution, motion and temperature are more appreciable than might be expected. Recent advancements in ionospheric simulation codes present the opportunity to investigate the relationship between geophysical conditions and geomagnetic location on resulting eclipse event ionosphere. Here we present computational simulation results using the Naval Research Lab (NRL) developed ionospheric modeling codes Sami2 and Sami3 (Sami2 is Another Model of the Ionosphere) modified with spatio-temporal photoionization attenuation functions derived from theory and empirical data.

  17. Eclipse and noneclipse differential photoelectron flux.

    NASA Technical Reports Server (NTRS)

    Knudsen, W. C.; Sharp, G. W.

    1972-01-01

    Differential photoelectron flux in the energy range of 3 to 50 eV has been measured in the lower ionosphere both during the March 7, 1970, solar eclipse and during a period 24 hours earlier. The two measurements were made with identical retarding potential analyzers carried on Nike-Apache rocket flights to a peak altitude of approximately 180 km. The differential electron flux spectrum within totality on the eclipse flight had the same shape but was a factor of 10 smaller in magnitude than that measured on the control day at altitudes between 120 and 180 km, an expected result for an eclipse function decreasing to 1/10 at totality. The differential flux spectrum measured in full sun has the same general energy dependence as that reported by Doering et al. (1970) but is larger by a factor of 2 to 10, depending on altitude.

  18. Five Millennium Catalog of Solar Eclipses: -1999 to +3000 (2000 BCE to 3000 CE)

    NASA Technical Reports Server (NTRS)

    Espenak, Fred; Meeus, Jean

    2008-01-01

    This catalog is a supplement to the "Five Millennium Canon of Solar Eclipses." It includes additional information for each eclipse that could not be included in the original 648-page publication because of size limits. The data tabulated for each eclipse include the catalog number, canon plate number, calendar date, Terrestrial Dynamical Time of greatest eclipse, (Delta)T, lunation number, Saros number, eclipse type, Quincena Lunar Eclipse parameter, gamma, eclipse magnitude, geographic coordinates of greatest eclipse (latitude and longitude), and the circumstances at greatest eclipse (i.e., Sun altitude and azimuth, path width, and central line duration). The Canon and the Catalog both use the same solar and lunar ephemerides as well as the same values of (Delta)T. This 1-to-1 correspondence between them will enhance the value of each. The researcher may now search, evaluate, and compare eclipses graphically (Canon) or textually (Catalog).

  19. First Results from the August 21, 2017, Total Solar Eclipse

    NASA Astrophysics Data System (ADS)

    Pasachoff, Jay M.

    2017-08-01

    I report on the observations planned and, weather permitting, made from our site in Salem, Oregon, at the August 21, 2017, total solar eclipse. I also give a first report on collaborators' successes, including Megamovie and simultaneous space observations. We also describe our participation in PBS's NOVA on the eclipse that was to be aired on public television on eclipse night. Our eclipse expedition is supported in large part by grants from the Solar Terrestrial Program of the Atmospheric Sciences Division of NSF and by the Committee for Research and Exploration of the National Geographic Society.

  20. Solar diameter measurements from eclipses as a solar variability proxy

    NASA Astrophysics Data System (ADS)

    Dunham, David W.; Sofia, Sabatino; Guhl, Konrad; Herald, David

    The widths of total solar eclipse paths depends on the diameter of the Sun, so if observations are obtained near both the northern and southern limits of the eclipse path, in principle, the angular diameter of the Sun can be measured. Concerted efforts have been made to obtain contact timings from locations near total solar eclipse path edges since the mid 19th century, and Edmund Halley organized a rather successful first effort in 1715. Members of IOTA have been making increasingly sophisticated observations of the Baily's bead phenomena near central solar eclipse path edges since 1970.

  1. Solar Eclipse: Concept of “Science” and “Language” Literacy

    NASA Astrophysics Data System (ADS)

    Haristiani, N.; Zaen, R.; Nandiyanto, A. B. D.; Rusmana, A. N.; Azis, F.; Danuwijaya, A. A.; Abdullah, A. G.

    2018-02-01

    The purpose of this study was to evaluate the concept of science and language literacy of solar eclipse. The study was conducted through a survey to 250 students with different ages (from 17 to 23 years old), grades, and majors in Universitas Pendidikan Indonesia. The survey was completed with a questionnaire consisting of 41 questions. In the case of the language literacy, experimental results showed that various expressions in facing the solar eclipse phenomenon are found. Relating to the science literacy, most students have good science understanding to the solar eclipse phenomenon. In conclusion, the understanding about the solar eclipse is affected by formal science education and religion understanding that they have been accepted since their childhood. These factors have also influenced the belief of Indonesian people to the solar eclipse myth and the way of expressions a language literacy.

  2. Total Eclipse From Onboard NASA's G-III Research Aircraft

    NASA Image and Video Library

    2017-09-13

    As the 2017 solar eclipse approaches and enters totality, NASA Armstrong staff and NASA senior management share their excitement and first-hand experience from aboard NASA’s Armstrong Flight Research Center Gulfstream III aircraft. The G-III aircraft flew at 35,000 feet above the coast of Oregon during the 2017 total solar eclipse, capturing some of the very first views of the 2017 total solar eclipse as it made its way across the United States.

  3. On the period determination of ASAS eclipsing binaries

    NASA Astrophysics Data System (ADS)

    Mayangsari, L.; Priyatikanto, R.; Putra, M.

    2014-03-01

    Variable stars, or particularly eclipsing binaries, are very essential astronomical occurrence. Surveys are the backbone of astronomy, and many discoveries of variable stars are the results of surveys. All-Sky Automated Survey (ASAS) is one of the observing projects whose ultimate goal is photometric monitoring of variable stars. Since its first light in 1997, ASAS has collected 50,099 variable stars, with 11,076 eclipsing binaries among them. In the present work we focus on the period determination of the eclipsing binaries. Since the number of data points in each ASAS eclipsing binary light curve is sparse, period determination of any system is a not straightforward process. For 30 samples of such systems we compare the implementation of Lomb-Scargle algorithm which is an Fast Fourier Transform (FFT) basis and Phase Dispersion Minimization (PDM) method which is non-FFT basis to determine their period. It is demonstrated that PDM gives better performance at handling eclipsing detached (ED) systems whose variability are non-sinusoidal. More over, using semi-automatic recipes, we get better period solution and satisfactorily improve 53% of the selected object's light curves, but failed against another 7% of selected objects. In addition, we also highlight 4 interesting objects for further investigation.

  4. Satellite observations of surface temperature during the March 2015 total solar eclipse

    PubMed Central

    2016-01-01

    The behaviour of remotely sensed land surface temperatures (LSTs) from the spinning-enhanced visible and infrared imager (SEVIRI) during the total solar eclipse of 20 March 2015 is analysed over Europe. LST is found to drop by up to several degrees Celcius during the eclipse, with the minimum LST occurring just after the eclipse mid-point (median=+1.5 min). The drop in LST is typically larger than the drop in near-surface air temperatures reported elsewhere, and correlates with solar obscuration (r=−0.47; larger obscuration = larger LST drop), eclipse duration (r=−0.62; longer duration = larger LST drop) and time (r=+0.37; earlier eclipse = larger LST drop). Locally, the LST drop is also correlated with vegetation (up to r=+0.6), with smaller LST drops occurring over more vegetated surfaces. The LSTs at locations near the coast and at higher elevation are also less affected by the eclipse. This study covers the largest area and uses the most observations of eclipse-induced surface temperature drops to date, and is the first full characterization of satellite LST during an eclipse (known to the author). The methods described could be applied to Geostationary Operational Environmental Satellite (GOES) LST data over North America during the August 2017 total solar eclipse. This article is part of the themed issue ‘Atmospheric effects of solar eclipses stimulated by the 2015 UK eclipse’. PMID:27550764

  5. The O-type eclipsing contact binary LY Aurigae - member of a quadruple system

    NASA Astrophysics Data System (ADS)

    Mayer, Pavel; Drechsel, Horst; Harmanec, Petr; Yang, Stephenson; Šlechta, Miroslav

    2013-11-01

    The eclipsing binary LY Aur (O9 II + O9 III) belongs to the rare class of early-type contact systems. We obtained 23 new spectra at the Ondřejov and Dominion Astrophysical Observatories, which were analysed with four older Calar Alto and one ELODIE archive spectra. A new result of this study is that the visual companion of LY Aur - the spectral lines of which are clearly seen in our spectra - is also an SB1 binary having an orbital period of 20.46d, an eccentric orbit, and a radial velocity semi-amplitude of 33 km s-1. The Hα line blend contains an emission component, which shows dependence on the orbital phase of the eclipsing system, with the strongest emission around the secondary eclipse. Revised elements of the eclipsing binary and the orbital solution of the companion binary are determined from our set of spectra and new light-curve solutions of the eclipsing pair. The mass of the primary of 25.5 M⊙ agrees well with its spectral type, whereas the secondary mass of 14 M⊙ is smaller than expected. From an O-C analysis of the minimum times of LY Aur that span more than 40 years, we found that the orbital period is decreasing, indicating the presence of interaction processes. The system is likely in a phase of non-conservative mass exchange. Based on spectral observations collected at the German-Spanish Observatory, Calar Alto, Spain; Dominion Astrophysical Observatory, Canada; Ondřejov Observatory, Czech Republic, and an archival Haute Provence Observatory ELODIE spectrum.

  6. Ionospheric effects over Europe during the solar eclipse on 20 March 2015

    NASA Astrophysics Data System (ADS)

    Hoque, Mainul; Jakowski, Norbert; Berdermann, Jens

    2017-04-01

    A total solar eclipse occurred on March 20, 2015 moving from the North-West Europe towards the North-East. Due to strong solar radiation changes dynamic processes were initiated in the atmosphere and ionosphere causing a measurable impact e.g. on the temperature and ionization during the eclipse. We analyzed the 20 March 2015 solar eclipse effects on the ionospheric structure over Europe using multi-sensor observations such as vertical sounding (VS) and Global Positioning System (GPS) measurements. Whereas the VS measurements are used to provide peak electron density information at the ionospheric F2, F1 and E layers over selected ionosonde stations, a dense network of GPS stations is used to provide high spatial resolution of the total electron content (TEC) estimates over Europe. We reconstructed the TEC maps with 5 minutes time resolution and thus investigated the original TEC maps and differential TEC maps obtained by subtracting 27 days medians from the actual TEC map values on 20 March 2015. By combining VS and GPS measurements the equivalent slab thickness has been estimated over several ionosonde stations to get information how the shape of the vertical electron density profile changes during the eclipse. The analysis of the solar eclipse on 20 March 2015 presented here will contribute to understand the ionospheric response on solar eclipses occurring at different latitudes. The observations indicate that a number of competitive processes initiated by an eclipse are often enhanced by dynamic forces associated with large scale geophysical conditions not directly impacted by the solar eclipse. Our TEC estimation shows that the total ionization reduces up to 60% (after bias correction 40%) as a function of obscuration. Since the 20 March 2015 eclipse occurred during the negative phase of a severe geomagnetic storm on 17 March 2015, the observed TEC depletion is higher than those reported earlier for 1999 and 2005 eclipses. Thus, a negative bias of up to 20

  7. Chandra Sees Remarkable Eclipse of Black Hole

    NASA Astrophysics Data System (ADS)

    2007-04-01

    A remarkable eclipse of a supermassive black hole and the hot gas disk around it has been observed with NASA's Chandra X-ray Observatory. This eclipse has allowed two key predictions about the effects of supermassive black holes to be tested. Just as eclipses of the Sun and moon give astronomers rare opportunities to learn about those objects, an alignment in a nearby galaxy has provided a rare opportunity to investigate a supermassive black hole. Illustrations of Black Hole Eclipse Illustrations of Black Hole Eclipse The supermassive black hole is located in NGC 1365, a galaxy 60 million light years from Earth. It contains a so called active galactic nucleus, or AGN. Scientists believe that the black hole at the center of the AGN is fed by a steady stream of material, presumably in the form of a disk. Material just about to fall into a black hole should be heated to millions of degrees before passing over the event horizon, or point of no return. The disk of gas around the central black hole in NGC 1365 produces copious X-rays but is much too small to resolve directly with a telescope. However, the disk was eclipsed by an intervening cloud, so observation of the time taken for the disk to go in and out of eclipse allowed scientists to estimate the size of the disk. Black Hole Animation Black Hole Animation "For years we've been struggling to confirm the size of this X-ray structure," said Guido Risaliti of the Harvard-Smithsonian Center for Astrophysics (CfA) in Cambridge, Mass, and the Italian Institute of Astronomy (INAF). "This serendipitous eclipse enabled us to make this breakthrough." The Chandra team directly measured the size of the X-ray source as about seven times the distance between the Sun and the Earth. That means the source of X-rays is about 2 billion times smaller than the host galaxy and only about 10 times larger than the estimated size of the black hole's event horizon, consistent with theoretical predictions. Chandra X-ray Image of NGC 1365

  8. Modeling the Eclipse

    ERIC Educational Resources Information Center

    Thornburgh, William R.; Tretter, Thomas R.

    2017-01-01

    This article describes a unit in which students investigate total solar eclipses, such as the one coming August 21, from several perspectives. It incorporates mathematical thinking and aligns with the "Next Generation Science Standard." This article refers to physical, virtual, and mathematical modeling. Various models and perspectives…

  9. Observations of the Eclipsing Millisecond Pulsar

    NASA Astrophysics Data System (ADS)

    Bookbinder, Jay

    1990-12-01

    FRUCHTER et al. (1988a) HAVE RECENTLY DISCOVERED a 1.6 MSEC PULSAR (PSR 1957+20) IN A 9.2 HOUR ECLIPSING BINARY SYSTEM. THE UNUSUAL BEHAVIOR OF THE DISPERSION MEASURE AS A FUNCTION OF ORBITAL PHASE, AND THE DISAPPEARANCE OF THE PULSAR SIGNAL FOR 50 MINUTES DURING EACH ORBIT, IMPLIES THAT THE ECLIPSES ARE DUE TO A PULSAR-INDUCED WIND FLOWING OFF OF THE COMPANION. THE OPTICAL COUNTERPART IS A 21ST MAGNITUDE OBJECT WHICH VARIES IN INTENSITY OVER THE BINARY PERIOD; ACCURATE GROUND-BASED OBSERVATIONS ARE PREVENTED BY THE PROXIMITY (0.7") OF A 20TH MAGNITUDE K DWARF. WE PROPOSE TO OBSERVE THE OPTICAL COUNTERPART IN A TWO-PART STUDY. FIRST, THE WF/PC WILL PROVIDE ACCURATE MULTICOLOR PHOTOMETRY, ENABLING US TO DETERMINE UNCONTAMINATED MAGNITUDES AND COLORS BOTH AT MAXIMUM (ANTI-ECLIPSE) AS WELL AS AT MINIMUM (ECLIPSE). SECOND, WE PROPOSE TO OBSERVE THE EXPECTED UV LINE EMISSION WITH FOS, ALLOWING FOR AN INTIAL DETERMINATION OF THE TEMPERATURE AND DENSITY STRUCTURE AND ABUNDANCES OF THE WIND THAT IS BEING ABLATED FROM THE COMPANION. STUDY OF THIS UNIQUE SYSTEM HOLDS ENORMOUS POTENTIAL FOR THE UNDERSTANDING OF THE RADIATION FIELD OF A MILLISECOND PULSAR AND THE EVOLUTION OF LMXRBs AND MSPs IN GENERAL. WE EXPECT THESE OBSERVATIONS TO PLACE VERY SIGNIFICANT CONTRAINTS ON MODELS OF THIS UNIQUE OBJECT.

  10. Public Education Plans for the 2017 August 21 Total Solar Eclipse

    NASA Astrophysics Data System (ADS)

    Pasachoff, Jay M.

    2016-06-01

    A total solar eclipse will cross the continental United States on 2017 August 21, the first such in 99 years and the first whose path of totality on land is entirely in the United States since 1776. People in the rest of the United States-as well as in Canada, Central America, and northern South America-will have a partial solar eclipse. Totality will range up to about 70 km in diameter, and will be visible from a path that extends from Oregon to South Carolina. Cloudiness statistics based on decades on satellite infrared imaging are more favorable for western sites. The sun's diameter will be 80% covered in Miami (south of totality) and New York (north of totality), and 70% covered in Los Angeles (south of totality). For the Working Group on Solar Eclipses of the International Astronomical Union, I maintain a website at http://eclipses.info that provides links to a wide variety of eclipse-related material and to useful websites run by others.Prior to this total eclipse, annular eclipses will cross Africa (from Gabon to Tanzania and Madagascar) and Isle de la Réunion on 2016 September 1, and Chile and Argentina on 2017 February 26, at which time we plan an eclipse workshop in Esquel, Argentina.For the forthcoming 2017 eclipse, we acknowledge grants to JMP and Williams College from the Solar Terrestrial Program of the Atmospheric and Geospace Sciences Division of the National Science Foundation and from the Committee for Research and Exploration of the National Geographic Society.

  11. Eclipse Across America on This Week @NASA – August 25, 2017

    NASA Image and Video Library

    2017-08-25

    The Aug. 21 eclipse across America generated interest and excitement far and wide. Our coverage of the historic eclipse – the first coast-to-coast total solar eclipse for the U.S. in 99 years – was widespread … Anchored from the College of Charleston, in South Carolina – we showed you views of the eclipse that only NASA could. Views from space, from Earth’s atmosphere and from the ground – with expert observation and analysis provided from many of the 14 states around the country, situated along the path of totality. That’s where thousands of people flocked – for the ultimate eclipse experience – total darkness in the middle of the day!

  12. New Eclipsing Contact Binary System in Auriga

    NASA Astrophysics Data System (ADS)

    Austin, S. J.; Robertson, J. W.; Justice, C.; Campbell, R. T.; Hoskins, J.

    2004-05-01

    We present data on a newly discovered eclipsing binary system. The serendipitous discovery of this variable star was made by J.W. Robertson analyzing inhomogeneous ensemble photometry of stars in the field of the cataclysmic variable FS Aurigae from Indiana University RoboScope data. We obtained differential time-series BVR photometry during 2003 of this field variable using an ensemble of telescopes including the university observatories at ATU, UCA and joint ventures with amateur observatories in the state of Arkansas (Whispering Pines Observatory and Nubbin Ridge Observatory). The orbital period of this eclipsing system is 0.2508 days. The B-V light curve indicates colors of 1.2 around quadrature, to nearly 1.4 at primary eclipse. Binary star light curve models that best fit the BVR differential photometry suggest that the system is a contact binary overfilling the inner Roche Lobe by 12%, a primary component with a temperature of 4350K, a secondary component with a temperature of 3500K, a mass ratio of 0.37, and an inclination of 83 degrees. We present BVR light curves, an ephemeris, and best fit model parameters for the physical characteristics of this new eclipsing binary system.

  13. Spirit Movie of Phobos Eclipse, Sol 675

    NASA Technical Reports Server (NTRS)

    2005-01-01

    [figure removed for brevity, see original site] Spirit Phobos Eclipse Animation

    NASA's Mars Exploration Rover Spirit observed the Martian moon Phobos entering the shadow of Mars during the night of the rover's 675th sol (Nov. 27, 2005). The panoramic camera captured 16 images, spaced 10 seconds apart, covering the period from when Phobos was in full sunlight to when it was entirely in shadow. As with our own Moon during lunar eclipses on Earth, even when in the planet's shadow, Phobos was not entirely dark. The small amount of light still visible from Phobos is a kind of 'Mars-shine' -- sunlight reflected through Mars' atmosphere and into the shadowed region.

    This clip is a sequence of the 16 images showing the eclipse at about 10 times normal speed. It shows the movement of Phobos from left to right as the moon enters the shadow. Scientists are using information about the precise timing of Martian moon eclipses gained from observations such as these to refine calculations about the orbital path of Phobos. The precise position of Phobos will be important to any future spacecraft taking detailed pictures of the moon or landing on its surface.

  14. PTF1 J191905.19+481506.2—A partially eclipsing AM CVn system discovered in the Palomar transient factory

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

    Levitan, David; Groot, Paul J.; Prince, Thomas A.

    2014-04-20

    We report on PTF1 J191905.19+481506.2, a newly discovered, partially eclipsing, outbursting AM CVn system found in the Palomar Transient Factory synoptic survey. This is only the second known eclipsing AM CVn system. We use high-speed photometric observations and phase-resolved spectroscopy to establish an orbital period of 22.4559(3) minutes. We also present a long-term light curve and report on the normal and super-outbursts regularly seen in this system, including a super-outburst recurrence time of 36.8(4) days. We use the presence of the eclipse to place upper and lower limits on the inclination of the system and discuss the number of knownmore » eclipsing AM CVn systems versus what would be expected.« less

  15. Effects of the March 2015 solar eclipse on near-surface atmospheric electricity.

    PubMed

    Bennett, A J

    2016-09-28

    Measurements of atmospheric electrical and standard meteorological parameters were made at coastal and inland sites in southern England during the 20 March 2015 partial solar eclipse. Clear evidence of a reduction in air temperature resulting from the eclipse was found at both locations, despite one of them being overcast during the entire eclipse. The reduction in temperature was expected to affect the near-surface electric field (potential gradient (PG)) through a reduction in turbulent transfer of space charge. No such effect could be unambiguously confirmed, however, with variability in PG and air-Earth current during the eclipse being comparable to pre- and post-eclipse conditions. The already low solar radiation for this latitude, season and time of day was likely to have contributed to the reduced effect of the eclipse on atmospheric electricity through boundary layer stability. The absence of a reduction in mean PG shortly after time of maximum solar obscuration, as observed during eclipses at lower geomagnetic latitude, implied that there was no significant change in atmospheric ionization from cosmic rays above background variability. This finding was suggested to be due to the relative importance of cosmic rays of solar and galactic origin at geomagnetic mid-latitudes.This article is part of the themed issue 'Atmospheric effects of solar eclipses stimulated by the 2015 UK eclipse'. © 2016 The Author(s).

  16. Photometric study of the pulsating, eclipsing binary OO DRA

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

    Zhang, X. B.; Deng, L. C.; Tian, J. F.

    We present a comprehensive photometric study of the pulsating, eclipsing binary OO Dra. Simultaneous B- and V-band photometry of the star was carried out on 14 nights. A revised orbital period and a new ephemeris were derived from the data. The first photometric solution of the binary system and the physical parameters of the component stars are determined. They reveal that OO Dra could be a detached system with a less-massive secondary component nearly filling its Roche lobe. By subtracting the eclipsing light changes from the data, we obtained the intrinsic pulsating light curves of the hotter, massive primary component.more » A frequency analysis of the residual light yields two confident pulsation modes in both B- and V-band data with the dominant frequency detected at 41.865 c/d. A brief discussion concerning the evolutionary status and the pulsation nature of the binary system is finally given.« less

  17. Epsilon Aurigae. [eclipsing binary system

    NASA Technical Reports Server (NTRS)

    Chapman, R. D.

    1985-01-01

    In April 1984, fourth contact ended the two year long eclipse of Epsilon Aurigae. An astrometric study of the study of the system was carried out by Van de kamp (1978) leading to the conclusion that the orbit is seen very close to edge on. The eclipse was monitored by a number of groups from the ground and from spacecraft such as the IUE. Ultraviolet observations of the system from IUE have thrown new light on the nature of the system that led to the conclusion that the secondary object is probably a cold, dusty accretion disk surrounding a star that is completely hidden inside the disk.

  18. Super Blue Moon Lunar Eclipse

    NASA Image and Video Library

    2018-01-31

    NASA TV provided coverage of Super Blue Moon Lunar Eclipse on Jan. 31. The full moon was the third in a series of “supermoons,” when the Moon is closer to Earth in its orbit -- known as perigee -- and about 14 percent brighter than usual. It was also the second full moon of the month, commonly known as a “blue moon.” As the super blue moon passed through Earth’s shadow, viewers in some locations experienced a total lunar eclipse. While in Earth’s shadow, the moon also took on a reddish tint – which is sometimes referred to as a “blood moon.”

  19. Solar Eclipse Education and Outreach Activities at APSU

    NASA Astrophysics Data System (ADS)

    Smith, J. Allyn; Buckner, Spencer L.; Adams, Mitzi; Meisch, Karen; Sudbrink, Don; Wright, Amy; Adams, Angela; Fagan, Ben

    2018-01-01

    The path of totality for the 21 August 2017 total solar eclipse passed directly over the APSU campus in north-central Tennessee. We discuss our public outreach and education efforts, both on campus and in the community, and present results and lessons learned from this event. We reached nearly 20,000 people via our efforts and hosted nearly 3000 viewers on campus on eclipse day. We also present our science activities and early results from those. On the whole, this event could be viewed as a large success for the university and the region, and the experiences will guide us in our efforts as we plan future eclipse activities.

  20. Eclipse Megamovie 2017: How did we do?

    NASA Astrophysics Data System (ADS)

    Hudson, H. S.; Bender, M.; Collier, B. L.; Johnson, C.; Koh, J.; Konerding, D.; Martinez Oliveros, J. C.; Peticolas, L. M.; White, V.; Zevin, D.

    2017-12-01

    The Eclipse Megamovie program, as set up for the Great American Eclipse of 21 August 2017, will have completed its first phase, data acquisition, on that day or shortly thereafter. Our objective was to create (with Google's help) a vast public archive of amateur and other photography, down to the smartphone level, of the corona itself and of Baily's Beads at the 2nd and 3rd contacts. The archive and the consumer electronics enabling it open a large new domain of parameter space for eclipse science. At whatever level we have succeeded, the archive is an historical first, and we hope that the it already has been a springboard for citizen-science projects. We will discuss the execution of the program and some of its science plans/results.

  1. Eclipsing Stellar Binaries in the Galactic Center

    NASA Astrophysics Data System (ADS)

    Li, Gongjie; Ginsburg, Idan; Naoz, Smadar; Loeb, Abraham

    2017-12-01

    Compact stellar binaries are expected to survive in the dense environment of the Galactic center. The stable binaries may undergo Kozai–Lidov oscillations due to perturbations from the central supermassive black hole (Sgr A*), yet the general relativistic precession can suppress the Kozai–Lidov oscillations and keep the stellar binaries from merging. However, it is challenging to resolve the binary sources and distinguish them from single stars. The close separations of the stable binaries allow higher eclipse probabilities. Here, we consider the massive star SO-2 as an example and calculate the probability of detecting eclipses, assuming it is a binary. We find that the eclipse probability is ∼30%–50%, reaching higher values when the stellar binary is more eccentric or highly inclined relative to its orbit around Sgr A*.

  2. Determination of the Io heat flow. 1: Eclipse observations

    NASA Technical Reports Server (NTRS)

    Sinton, W. M.; Kaminski, C.

    1983-01-01

    The thermal emission from Io during eclipse by Jupiter yields data from which the total thermal flux from the volcanoes on the satellite surface can be estimated. Thermal infrared observations in spectral bands between 3.5 and 30 microns of five Io eclipse reappearances and one eclipse disappearance are reported and discussed. The thermal emission of the volcanoes which occurs almost all of the time was determined from the Io heat flux data. The thermal observations of Io are discussed with respect to previous thermophysical theories.

  3. Five Millennium Catalog of Solar Eclipses: -1999 to +3000 (2000 BCE to 3000 CE)-Revised

    NASA Technical Reports Server (NTRS)

    Espenak, Fred; Meeus, Jean

    2009-01-01

    This catalog is a supplement to the "Five Millennium Canon of Lunar Eclipses. "It includes additional information for each eclipse that could not be included in the original publication because of size limits. The data tabulated for each eclipse include the catalog number, canon plate number, calendar date, Terrestrial Dynamical Time of greatest eclipse, (Delta)T, lunation number, Saros number, eclipse type, Quincena Solar Eclipse parameter, gamma, penumbral and umbral eclipse magnitudes, durations of penumbral, partial and total eclipse phases, and geographic coordinates of greatest eclipse(latitude and longitude). The Canon and the Catalog both use the same solar and lunar ephemerides as well as the same values of (Delta)T. This 1-to-1 correspondence between them will enhance the value of each. The researcher may now search, evaluate, and compare eclipses graphically (Canon) or textually (Catalog).

  4. New Zealand Astronomy and the 9 September 1885 Total Solar Eclipse

    NASA Astrophysics Data System (ADS)

    Orchiston, Wayne; Rowe, Glen

    The second half of the nineteenth century saw a blossoming of interest in solar eclipses as astronomers tried to establish whether the corona was a solar, lunar or terrestrial phenomenon, and as they investigated the nature of the corona, the chromosphere and prominences. Critical in these investigations were astronomy's newest allies: photography and spectroscopy. Photography was used with great effectiveness throughout the half century, but spectroscopy was first applied during the `Indian eclipse' of 1868. Thereafter, almost every total solar eclipse was subjected to scrutiny, the intensity of which depended upon the duration of the eclipse and the location of its path of totality. The first total solar eclipse visible from New Zealand following European settlement occurred on 9 September 1885, and attracted the attention of professional scientists and amateur astronomers. The centre of the path of totality extended from West Wanganui Inlet on the far northern reaches of the west coast of the South Island to Castle Point on the Wairarapa Coast, and a total eclipse was visible from population centres like Collingwood, Nelson, Picton, Wellington, Otaki, Palmerston North, Wanganui and throughout the Wairarapa. In this chapter we examine this eclipse, in the context of New Zealand astronomy and the international development of solar physics.

  5. Solar Eclipse-Induced Changes in the Ionosphere over the Continental US

    NASA Astrophysics Data System (ADS)

    Erickson, P. J.; Zhang, S.; Goncharenko, L. P.; Coster, A. J.; Hysell, D. L.; Sulzer, M. P.; Vierinen, J.

    2017-12-01

    For the first time in 26 years, a total solar eclipse occurred over the continental United States on 21 August 2017, between 16:00-20:00 UT. We report on American solar eclipse observations of the upper atmosphere, conducted by a team led by MIT Haystack Observatory. Efforts measured ionospheric and thermospheric eclipse perturbations. Although eclipse effects have been studied for more than 50 years, recent major sensitivity and resolution advances using radio-based techniques are providing new information on the eclipse ionosphere-thermosphere-mesosphere (ITM) system response. Our study was focused on quantifying eclipse effects on (1) traveling ionospheric disturbances (TIDs) and atmospheric gravity waves (AGWs); (2) spatial ionospheric variations associated with the eclipse; and (3) altitudinal and temporal ionospheric profile variations. We present selected early findings on ITM eclipse response including a dense global network of 6000 GNSS total electron content (TEC) receivers (100 million measurements per day; 1x1 degree spatial grid) and the Millstone Hill and Arecibo incoherent scatter radars. TEC depletions of up to 60% in magnitude were associated with the eclipse umbra and penumbra and consistently trailed the eclipse totality center. TEC enhancements associated with prominent orographic features were observed in the western US due to complex interactions as the lower atmosphere cooled in response to decreasing EUV energy inputs. Strong TIDs in the form of bow waves, stern waves, and a stern wake were observed in TEC data. Altitude-resolved plasma parameter profiles from Millstone Hill saw a nearly 50% decrease in F region electron density in vertical profiles, accompanied by a corresponding 200-250 K decrease in electron temperature. Wide field Millstone Hill radar scans showed similar decreases in electron density to the southwest, maximizing along the line of closest approach to totality. Data is available to the research community through the MIT

  6. Amazonia Introduced to General Relativity: The May 29, 1919, Solar Eclipse from a North-Brazilian Point of View

    NASA Astrophysics Data System (ADS)

    Crispino, Luís C. B.; de Lima, Marcelo C.

    2016-12-01

    In 1919, A. C. D. Crommelin and C. R. Davidson, British astronomers from the Greenwich Observatory in England, passed by Amazonia on their Brazilian journey aiming to measure the bending of stars' light rays during the total solar eclipse of May 29, 1919, and thereby put the theory of general relativity to the test. In the context of Crommelin's and Davidson's visit, we discuss how Amazonia was introduced to Einstein's theory of gravitation, and also the observations and repercussions of the May 29, 1919, solar eclipse in Belém, capital city of the North-Brazilian Pará state.

  7. The National Eclipse Weather Experiment: an assessment of citizen scientist weather observations

    PubMed Central

    2016-01-01

    The National Eclipse Weather Experiment (NEWEx) was a citizen science project designed to assess the effects of the 20 March 2015 partial solar eclipse on the weather over the United Kingdom (UK). NEWEx had two principal objectives: to provide a spatial network of meteorological observations across the UK to aid the investigation of eclipse-induced weather changes, and to develop a nationwide public engagement activity-based participation of citizen scientists. In total, NEWEx collected 15 606 observations of air temperature, cloudiness and wind speed and direction from 309 locations across the UK, over a 3 h window spanning the eclipse period. The headline results were processed in near real time, immediately published online, and featured in UK national press articles on the day of the eclipse. Here, we describe the technical development of NEWEx and how the observations provided by the citizen scientists were analysed. By comparing the results of the NEWEx analyses with results from other investigations of the same eclipse using different observational networks, including measurements from the University of Reading’s Atmospheric Observatory, we demonstrate that NEWEx provided a fair representation of the change in the UK meteorological conditions throughout the eclipse. Despite the simplicity of the approach adopted, robust reductions in both temperature and wind speed during the eclipse were observed. This article is part of the themed issue ‘Atmospheric effects of solar eclipses stimulated by the 2015 UK eclipse’. PMID:27550767

  8. Geospatial Analysis of Low-frequency Radio Signals Collected During the 2017 Solar Eclipse

    NASA Astrophysics Data System (ADS)

    Liles, W. C.; Nelson, J.; Kerby, K. C.; Lukes, L.; Henry, J.; Oputa, J.; Lemaster, G.

    2017-12-01

    The total solar eclipse of 2017, with a path that crosses the continental United States, offers a unique opportunity to gather geospatially diverse data. The EclipseMob project has been designed to crowdsource this data by building a network of citizen scientists across the country. The project focuses on gathering low-frequency radio wave data before, during, and after the eclipse. WWVB, a 60 KHz transmitter in Ft. Collins, CO operated by the National Institutes of Standard and Technology, will provide the transmit signal that will be observed by project participants. Participating citizen scientists are building simple antennas and receivers designed by the EclipseMob team and provided to participants in the form of "receiver kits." The EclipseMob receiver downsamples the 60 KHz signal to 18 KHz and supplies the downsampled signal to the audio jack of a smartphone. A dedicated app is used to collect data and upload it to the EclipseMob server. By studying the variations in WWVB amplitude observed during the eclipse at over 150 locations across the country, we aim to understand how the ionization of the D layer of the ionosphere is impacted by the eclipse as a function of both time and space (location). The diverse locations of the EclipseMob participants will provide data from a wide variety of propagation paths - some crossing the path of the total eclipse, and some remaining on the same side of the eclipse path as the transmitter. Our initial data analysis will involve identifying characteristics that define geospatial relationships in the behavior of observed WWVB signal amplitudes.

  9. On the Importance of Solar Eclipse Geometry in the Interpretation of Ionospheric Observations

    NASA Astrophysics Data System (ADS)

    Stankov, S.; Verhulst, T. G. W.

    2017-12-01

    A reliable interpretation of solar eclipse effects on the geospace environment, and on the ionosphere in particular, necessitates a careful consideration of the so-called eclipse geometry. A solar eclipse is a relatively rare astronomical phenomenon, which geometry is rather complex, specific for each event, and fast changing in time. The standard, most popular way to look at the eclipse geometry is via the two-dimensional representation (map) of the solar obscuration on the Earth's surface, in which the path of eclipse totality is drawn together with isolines of the gradually-decreasing eclipse magnitude farther away from this path. Such "surface maps" are widely used to readily explain some of the solar eclipse effects including, for example, the well-known decrease in total ionisation (due to the substantial decrease in solar irradiation), usually presented by the popular and easy to understand ionospheric characteristic of Total Electron Content (TEC). However, many other effects, especially those taking place at higher altitudes, cannot be explained in this fashion. Instead, a complete, four-dimensional (4D) description of the umbra (and penumbra), would be required. This presentation will address the issue of eclipse geometry effects on various ionospheric observations carried out during the total solar eclipse of August 21, 2017. In particular, GPS-based TEC and ionosonde measurements will be analysed and the eclipse effects on the ionosphere will be interpreted with respect to the actual eclipse geometry at ionospheric heights. Whenever possible, a comparison will be made with results from previous events, such as the ones from March 20, 2015 and October 3, 2005.

  10. Approaches to characterise chromatographic column performance based on global parameters accounting for peak broadening and skewness.

    PubMed

    Baeza-Baeza, J J; Pous-Torres, S; Torres-Lapasió, J R; García-Alvarez-Coque, M C

    2010-04-02

    Peak broadening and skewness are fundamental parameters in chromatography, since they affect the resolution capability of a chromatographic column. A common practice to characterise chromatographic columns is to estimate the efficiency and asymmetry factor for the peaks of one or more solutes eluted at selected experimental conditions. This has the drawback that the extra-column contributions to the peak variance and skewness make the peak shape parameters depend on the retention time. We propose and discuss here the use of several approaches that allow the estimation of global parameters (non-dependent on the retention time) to describe the column performance. The global parameters arise from different linear relationships that can be established between the peak variance, standard deviation, or half-widths with the retention time. Some of them describe exclusively the column contribution to the peak broadening, whereas others consider the extra-column effects also. The estimation of peak skewness was also possible for the approaches based on the half-widths. The proposed approaches were applied to the characterisation of different columns (Spherisorb, Zorbax SB, Zorbax Eclipse, Kromasil, Chromolith, X-Terra and Inertsil), using the chromatographic data obtained for several diuretics and basic drugs (beta-blockers). Copyright (c) 2010 Elsevier B.V. All rights reserved.

  11. Eclipsing cataclysmic variables. Deep eclipses in H0928+501. YY Draconis, the whirling dervish. New x ray pulsar candidates from HEAO-1

    NASA Technical Reports Server (NTRS)

    Patterson, Joseph

    1993-01-01

    The status report covering the period from 1 June 1992 to 31 May 1993 is included. Areas of research include: (1) eclipsing cataclysmic variables; (2) deep eclipses in H0928+501; (3) YY Draconis, the Whirling Dervish; and (4) new x ray pulsar candidates from HEAO-1.

  12. Spatiotemporal change of sky polarization during the total solar eclipse on 29 March 2006 in Turkey: polarization patterns of the eclipsed sky observed by full-sky imaging polarimetry.

    PubMed

    Sipocz, Brigitta; Hegedüs, Ramón; Kriska, György; Horváth, Gábor

    2008-12-01

    Using 180 degrees field-of-view (full-sky) imaging polarimetry, we measured the spatiotemporal change of the polarization of skylight during the total solar eclipse on 29 March 2006 in Turkey. We present our observations here on the temporal variation of the celestial patterns of the degree p and angle alpha of linear polarization of the eclipsed sky measured in the red (650 nm), green (550 nm), and blue (450 nm) parts of the spectrum. We also report on the temporal and spectral change of the positions of neutral (unpolarized, p = 0) points, and points with local minima or maxima of p of the eclipsed sky. Our results are compared with the observations performed by the same polarimetric technique during the total solar eclipse on 11 August 1999 in Hungary. Practically the same characteristics of celestial polarization were encountered during both eclipses. This shows that the observed polarization phenomena of the eclipsed sky may be general.

  13. Total solar eclipse of 3 November 1994

    NASA Technical Reports Server (NTRS)

    Espenak, Fred; Anderson, Jay

    1993-01-01

    A total eclipse of the Sun will be visible from the southern half of the Western Hemisphere on 3 November 1994. The path of the Moon's shadow passes through Peru, Chile, Bolivia, Paraguay, and Brazil. Detailed predictions for this event are presented and include tables of geographic coordinates of the path of totality, local circumstances for hundreds of cities, maps of the path of total and partial eclipse, weather prospects, and the lunar limb profile.

  14. ... and more eclipses!

    NASA Astrophysics Data System (ADS)

    1999-01-01

    To prepare students for the big day, the Association for Science Education has produced activity packs aimed at primary and secondary levels, including photocopiable pages accompanied by detailed notes for teachers. Safe viewing, recording and reporting, modelling and explaining, understanding solar physics, as well as using IT and the Internet are all covered, to enable both teachers and students to make the most of the 1999 eclipse experience. ASE Booksales at College Lane, Hatfield, Herts AL10 9AA (tel: 01707 283000, free fax: 0800 371856) should be contacted for further details. Also available early in 1999 will be three Investigation packs to stimulate a scientific approach to the 1999 event. The School of Science and Mathematics at Sheffield Hallam University has worked in collaboration with UK scientists active in the field to develop the materials, and there will be opportunities for users to work together across the UK and not just in the zone of totality. Thus a pool of results can be built up nationwide of what is happening on the day. One pack is aimed at primary children, the second at secondary students and the third at the general public, including families with young children. Further information can be obtained from Sheffield Hallam University (tel: 0114 225 4881). And finally...! The magic of solar eclipses can be observed from the comfort of your own armchair thanks to some of the stunning visual images available from UCLimages. A 1999 calendar with 12 photographs taken by Dr Francisco Diego, five posters (size 60 cm by 42 cm) and a widescreen video can all be ordered from `Solar eclipse', UCLimages, 48 Riding House Street, London W1P 7PL (tel: 0171 504 9375, fax: 0171 436 1738, e-mail: images@ucl.ac.uk).

  15. EPIC 219217635: A Doubly Eclipsing Quadruple System Containing an Evolved Binary

    NASA Astrophysics Data System (ADS)

    Borkovits, T.; Albrecht, S.; Rappaport, S.; Nelson, L.; Vanderburg, A.; Gary, B. L.; Tan, T. G.; Justesen, A. B.; Kristiansen, M. H.; Jacobs, T. L.; LaCourse, D.; Ngo, H.; Wallack, N.; Ruane, G.; Mawet, D.; Howell, S. B.; Tronsgaard, R.

    2018-05-01

    We have discovered a doubly eclipsing, bound, quadruple star system in the field of K2 Campaign 7. EPIC 219217635 is a stellar image with Kp = 12.7 that contains an eclipsing binary (`EB') with PA = 3.59470 d and a second EB with PB = 0.61825 d. We have obtained followup radial-velocity (`RV') spectroscopy observations, adaptive optics imaging, as well as ground-based photometric observations. From our analysis of all the observations, we derive good estimates for a number of the system parameters. We conclude that (1) both binaries are bound in a quadruple star system; (2) a linear trend to the RV curve of binary A is found over a 2-year interval, corresponding to an acceleration, \\dot{γ }= 0.0024 ± 0.0007 cm s-2; (3) small irregular variations are seen in the eclipse-timing variations (`ETVs') detected over the same interval; (4) the orbital separation of the quadruple system is probably in the range of 8-25 AU; and (5) the orbital planes of the two binaries must be inclined with respect to each other by at least 25°. In addition, we find that binary B is evolved, and the cooler and currently less massive star has transferred much of its envelope to the currently more massive star. We have also demonstrated that the system is sufficiently bright that the eclipses can be followed using small ground-based telescopes, and that this system may be profitably studied over the next decade when the outer orbit of the quadruple is expected to manifest itself in the ETV and/or RV curves.

  16. Period analysis of the eclipsing binary AI Dra

    NASA Astrophysics Data System (ADS)

    Zasche, P.; Uhlář, R.; Svoboda, P.

    2010-03-01

    The eclipsing binary system AI Dra reveals changes of its orbital period. These variations could be described as a result of orbiting the eclipsing pair around a common center of mass with two unseen companions with the periods about 18 and 43 years together with a steady period increase. Fourteen new minima observations were carried out by the authors.

  17. Educational and Public Outreach Strategies in Anticipation of the 2017 U.S. Total Solar Eclipse

    NASA Astrophysics Data System (ADS)

    Fulco, C.

    2015-12-01

    Those who have experienced a total solar eclipse will travel to every corner of the Earth to observe one, such is its spectacular nature. So it is fortunate indeed to have this remarkable event come to the U.S. in less than two years, with its path of totality from Oregon to South Carolina within a day's drive for most of the nation's population. The date of the 21 August 2017 "Great American Eclipse" is rapidly approaching, and with focus on science literacy in U.S. schools greater than ever, educational and public outreach (EPO) must begin in earnest to maximize the scientific and educational benefits from this rare event. As every location in the U.S. will observe at least a partial eclipse, having EPO strategies in place ensures that the greatest number of students and other observers throughout the country will: a) be aware of and prepared for this event, b) observe (and record) it safely and knowledgeably, and c) gain an increased awareness of the natural world. The need for teachers to promote scientific literacy through curriculum is critical for this event. Despite an increased presence of technology in the classroom, more rigorous educational learning standards and virtually instantaneous access to information, data show that science illiteracy in U.S. schools and in the general population is still widespread. In addition, much fear, ignorance and confusion continue to surround eclipses. Many school districts plan to keep students indoors during the eclipse, while the media can be expected to instruct the public to do the same, thus depriving would-be observers of an unforgettable and most likely a once-in-a-lifetime experience. It would be a tragedy on many levels if this eclipse were not viewed, recorded and remembered live and outdoors--not indoors watching on media--by as many persons as possible. Proper EPO strategies performed with ample lead time can ensure that the 2017 U.S. Total Solar Eclipse will be a success from coast-to-coast, and with it, a

  18. Outreach to Scientists and to the Public about the Scientific Value of Solar Eclipses

    NASA Astrophysics Data System (ADS)

    Pasachoff, J.

    2017-12-01

    The Great American Eclipse of August 21, 2017, provided an unprecedented opportunity for outreach among American audiences on a giant scale in the age of social media. Professonal scientists and other educators, however, were not exempt from ignorance of the remaining scientific value of observing solar eclipses, often mistakenly thinking that space satellites or mountaintop observatories could make artificial eclipses as good as natural ones, which they can't. Further, as Chair of the Working Group on Eclipses of the International Astronomical Union and as a frequent observer of solar eclipses in other countries, I felt an obligation to provide at-least-equal hospitality in our country. Here I discuss our welcome to and interaction with eclipse scientists from Greece, Slovakia, Australia, Bulgaria, Iran, China, and Japan and their participation in the eclipse observations. I describe my own outreach about the still-vital solar-eclipse observations through my August 2017 articles in Nature Astronomy and Scientific American as well as through book reviews in Nature and Phi Beta Kappa's Key Reporter and co-authorship of a Resource Letter on Observing Solar Eclipses in the July issue og the American Journal of Physics. I describe my eclipse-day Academic Minute on National Public Radio via WAMC and on http://365daysofastronomy.org, a website started during the International Year of Astronomy. I discuss my blog post on lecturing to pre-school through elementary-school students for the National Geographic Society's Education Blog. I show my Op-Ed pre-eclipse in the Washington Post. I discuss our eclipse-night broadcast of an eclipse program on PBS's NOVA, and its preparation over many months, back as far and farther than the February 26, 2017, annular solar eclipse observed from Argentinian Patagonia, with images from prior eclipses including 2013 in Gabon and 2015 in Svalbard. My work at the 2017 total solar eclipse was supported in large part with grants from the

  19. Public outreach and education during the 2016 total solar eclipse in Palu and Malang

    NASA Astrophysics Data System (ADS)

    Rachmadian, A. P.; Kunjaya, C.; Wahono, W.; Anugrah, A. A.

    2016-11-01

    MAGIC (Ma Chung Galactic Club) of Ma Chung University, Malang, is one of the amateur astronomers club who did public outreach and education during the Total Solar Eclipse March 9, 2016. The motivation for doing this was the bad experience during Total Solar Eclipse 1983. At that time the Indonesian government forbid the people to observe the Total Solar Eclipse in a way to avoid blindness. We try to fix this misunderstanding by educating people the safe way to enjoy the partial and total solar eclipse. MAGIC team was divided into two teams, one team went to Palu and did the solar eclipse related education in six high schools before and during the eclipse. The other team did the observation on Ma Chung University campus, Malang, to accompany people who want to see the partial solar eclipse through filtered telescopes. The sky during the solar eclipse was clear both in Malang and Palu. People were very excited and satisfied with the solar eclipse, and their interest to astronomy is increased.

  20. Eclipse 2017: Partnering with NASA MSFC to Inspire Students

    NASA Technical Reports Server (NTRS)

    Fry, Craig " Ghee" ; Adams, Mitzi; Gallagher, Dennis; Krause, Linda

    2017-01-01

    NASA's Marshall Space Flight Center (MSFC) is partnering with the U.S. Space and Rocket Center (USSRC), and Austin Peay State University (APSU) to engage citizen scientists, engineers, and students in science investigations during the 2017 American Solar Eclipse. Investigations will support the Citizen Continental America Telescopic Eclipse (CATE), Ham Radio Science Citizen Investigation(HamSCI), and Interactive NASA Space Physics Ionosphere Radio Experiments (INSPIRE). All planned activities will engage Space Campers and local high school students in the application of the scientific method as they seek to explore a wide range of observations during the eclipse. Where planned experiments touch on current scientific questions, the camper/students will be acting as citizen scientists, participating with researchers from APSU and MSFC. Participants will test their expectations and after the eclipse, share their results, experiences, and conclusions to younger Space Campers at the US Space & Rocket Center.

  1. The Unique Scientific Assets of Multi-Wavelength Total Solar Eclipse Observations

    NASA Astrophysics Data System (ADS)

    Habbal, S. R.; Druckmuller, M.; Ding, A.

    2017-12-01

    Total solar eclipses continue to yield new discoveries regarding the dynamics and thermodynamics of the corona, due to the radial span of the field of view available during totality, starting from the solar surface out to several solar radii, and due to the diagnostic potential provided by coronal emission lines. Scientific highlights from past eclipse observations as well as from the 21 August 2017 eclipse, now spanning a solar cycle, will be presented. These include white light and spectral line imaging as well as imaging spectrometry. Emphasis will be placed on the unique insights into the origin of dynamic structures captured in eclipse images, and the temperature distribution in the corona derived from these eclipse observations. Implications of these results for the general problem of coronal heating, as well as for the next generation of space instrumentation will be discussed.

  2. Properties OF M31. V. 298 eclipsing binaries from PAndromeda

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

    Lee, C.-H.; Koppenhoefer, J.; Seitz, S.

    2014-12-10

    The goal of this work is to conduct a photometric study of eclipsing binaries in M31. We apply a modified box-fitting algorithm to search for eclipsing binary candidates and determine their period. We classify these candidates into detached, semi-detached, and contact systems using the Fourier decomposition method. We cross-match the position of our detached candidates with the photometry from Local Group Survey and select 13 candidates brighter than 20.5 mag in V. The relative physical parameters of these detached candidates are further characterized with the Detached Eclipsing Binary Light curve fitter (DEBiL) by Devor. We will follow up the detachedmore » eclipsing binaries spectroscopically and determine the distance to M31.« less

  3. Simultaneous determination of ginsenoside Rb1, naringin, ginsenoside Rb2 and oridonin in rat plasma by LC-MS/MS and its application to a pharmacokinetic study after oral administration of Weifuchun tablet.

    PubMed

    Jin, Yiran; Tian, Tingting; Ma, Yinghua; Xu, Huijun; Du, Yingfeng

    2015-09-01

    A sensitive, specific and rapid liquid chromatography-mass spectrometry (LC-MS) method was developed and validated for analysis of ginsenoside Rb1, naringin, ginsenoside Rb2 and oridonin in rat plasma using sulfamethoxazole as an internal standard (IS). Separation was conducted out on an Agilent Eclipse XDB C18 column with liner gradient elution using acetonitrile (A) and 0.1% aqueous acetic acid (B). A tandem mass spectrometric detection was conducted using multiple reaction monitoring (MRM) via an electrospray ionization (ESI) source. A novel multi-determination-periods program was executed to achieve a higher sensitivity by setting three scanning periods. All analytes exhibited good linearity within the concentration range (r>0.9973). The lower limits of quantitation (LLOQ) of ginsenoside Rb1, naringin, ginsenoside Rb2 and oridonin were 2.64, 4.32, 2.32 and 1.56ng/mL, respectively. Intra-day and inter-day precisions of the investigated components exhibited an RSD within 8.3%, and the accuracy (RE) ranged from -8.6% to 6.0% at all quality control levels. The developed method was successfully applied to a pharmacokinetic study of ginsenoside Rb1, naringin, ginsenoside Rb2 and oridonin in rats after oral administration of a Weifuchun tablet. Copyright © 2015 Elsevier B.V. All rights reserved.

  4. Periodicity and eclipse minima timing of CM Draconis.

    NASA Astrophysics Data System (ADS)

    Vázquez-Martín, S.; Deeg, H. J.; Dreizler, S.; von Essen, C.; Kozhevnikov, V. P.

    2015-05-01

    Periodic deviations from a linear ephemeris of a binary star's eclipses can indicate the presence of a third body in orbit around both. Hints for such companion around the M4.5/M4.5 binary CMDra were published by Deeg et al. (2008). The assignment of a planet in the CMDra system can however only be accepted if the earlier observed periodicity trends can be verified through further observations over several years. For eclipsing binary stars of low mass, the method of eclipse minimum timing allows one to set mass limits for the detection of a third body. Deeg et al. (2008) concluded that the two possibilities for the source of CMDra's timing variations that remain valid are a planet of a few Jupiter masses on a two decade-long orbit, or an object on a century-to-millenium long orbit with masses 1.5M_J < M_{p} < 0.1M_{⊙}. However, they concluded that it is necessary to do continued observations of the timing of CMDra's eclipses to be decisive regarding the continued viability of the sinusoidal-fit-model, and hence, about the validity of a Jovian-type planet in a circumbinary orbiting around the system. Here we update the analysis of Deeg et al. (2008), including further data presented in Morales et al. (2009r) and new observations taken at Ural Observatory (2008-2013). Eclipse minimum times were obtained using the Kwee-van-Woerden method.

  5. 75 FR 45075 - Airworthiness Directives; Eclipse Aerospace, Inc. Model EA500 Airplanes

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-02

    ... Airworthiness Directives; Eclipse Aerospace, Inc. Model EA500 Airplanes AGENCY: Federal Aviation Administration... in the Federal Register on July 9, 2010 (75 FR 39472), and applies to certain Eclipse Aerospace, Inc... Federal holidays. For service information identified in this proposed AD, contact Eclipse Aerospace, Inc...

  6. KIC 11401845: An Eclipsing Binary with Multiperiodic Pulsations and Light-travel Time

    NASA Astrophysics Data System (ADS)

    Lee, Jae Woo; Hong, Kyeongsoo; Kim, Seung-Lee; Koo, Jae-Rim

    2017-02-01

    We report the {\\text{}}{Kepler} photometry of KIC 11401845 displaying multiperiodic pulsations, superimposed on binary effects. Light-curve synthesis shows that the binary star is a short-period detached system with a very low mass ratio of q = 0.070 and filling factors of F1 = 45% and F2 = 99%. Multiple-frequency analyses were applied to the light residuals after subtracting the synthetic eclipsing curve from the observed data. We detected 23 frequencies with signal-to-noise ratios larger than 4.0, of which the orbital harmonics (f4, f6, f9, f15) in the low-frequency domain may originate from tidally excited modes. For the high frequencies of 13.7-23.8 day-1, the period ratios and pulsation constants are in the ranges of {P}{pul}/{P}{orb}=0.020{--}0.034 and Q = 0.018-0.031 days, respectively. These values and the position on the Hertzsprung-Russell diagram demonstrate that the primary component is a δ Sct pulsating star. We examined the eclipse timing variation of KIC 11401845 from the pulsation-subtracted data and found a delay of 56 ± 17 s in the arrival times of the secondary eclipses relative to the primary eclipses. A possible explanation of the time shift may be some combination of a light-travel-time delay of about 34 s and a very small eccentricity of e\\cos ω < 0.0002. This result represents the first measurement of the Rømer delay in noncompact binaries.

  7. Impact of the 2017 Solar Eclipse on Smart Grid

    NASA Astrophysics Data System (ADS)

    Reda, I.; Andreas, A.; Sengupta, M.; Habte, A.

    2017-12-01

    With the increasing interest in using solar energy as a major contributor to renewable energy utilization, and with the focus on using smart grids to optimize the use of electrical energy based on demand and resources from different locations, arises the need to know the Moon position in the sky with respect to the Sun. When a solar eclipse occurs, the Moon disk might totally or partially shade the Sun disk, which can affect the irradiance level from the sun disk, consequently, a resource on the grid is affected. The Moon position can then provide the smart grid users with information about potential total or partial solar eclipse at different locations in the grid, so that other resources on the grid can be directed where this might be needed when such phenomena occurs. At least five solar eclipses occur yearly at different locations on earth, they can last three hours or more depending on the location, which can have devastating effects on the smart grid users. On August 21, 2017 a partial solar eclipse will occur at the National Renewable Energy Laboratory in Golden, Colorado, USA. The solar irradiance will be measured during the eclipse and compared to the data generated by a model for validation.

  8. 40 CFR 180.1284 - Ammonium salts of higher fatty acids (C8-C18 saturated; C8-C12 unsaturated); exemption from the...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Ammonium salts of higher fatty acids... Ammonium salts of higher fatty acids (C8-C18 saturated; C8-C12 unsaturated); exemption from the requirement of a tolerance. Ammonium salts of C8-C18 saturated and C8-C12 unsaturated higher fatty acids are...

  9. 40 CFR 180.1284 - Ammonium salts of higher fatty acids (C8-C18 saturated; C8-C12 unsaturated); exemption from the...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 24 2011-07-01 2011-07-01 false Ammonium salts of higher fatty acids... Ammonium salts of higher fatty acids (C8-C18 saturated; C8-C12 unsaturated); exemption from the requirement of a tolerance. Ammonium salts of C8-C18 saturated and C8-C12 unsaturated higher fatty acids are...

  10. Preparing for Eclipse 2017 on This Week @NASA – August 11, 2017

    NASA Image and Video Library

    2017-08-11

    The Aug. 21 total solar eclipse across America is generating a lot of interest – and a lot of questions. You’ll find answers to many of your eclipse questions at NASA’s Eclipse 2017 website -- eclipse2017.nasa.gov. The site is full of information to help you prepare for this rare celestial event – including eclipse-related activities, events, viewing safety tips, and other resources. Then, on the day of the eclipse, you can see the event “Through the Eyes of NASA” – during a special NASA TV broadcast that includes coast-to-coast coverage from the ground, from the air and from space. Coverage begins with a special pre-show at noon eastern – followed by in-depth coverage at 1pm. You can also watch on Aug. 21 at www.nasa.gov/eclipselive. Also, TDRS-M Update, Webb’s Sunshield Layers Installed, RS-25 Engine Testing Rolls On, and Chief Technologist Visits Industry Partner!

  11. Girl Scout Stars: Engaging Girl Scouts in the 2017 Total Eclipse

    NASA Astrophysics Data System (ADS)

    Harman, P. K.

    2017-12-01

    Reaching for the Stars: NASA Science for Girl Scouts (Girl Scout Stars) engages Girl Scouts in observing the 2017 eclipse. Three councils are host-sponsors of Girl Scout Total Eclipse Destinations,. Total Eclipse of the Heartland, sponsored by Girl Scouts of Southern Illinois, begins with planetarium, and science center visits in St. Louis, and transits to Carbondale for the eclipse. The Great Eclipse Adventure, sponsored by the Girl Scouts of the Missouri Heartland, features hands-on science activities led by Astronomy and Physics faculty and grad students at University of Missouri, Columbia, MO, and observing the eclipse at a camp nearby. Eyes to the Sky: A Once in a Lifetime Destination, by the Girl Scouts of South Carolina - Mountains to Midlands, visits a Challenger Center, a planetarium, and observatory, and culminates at Camp MaBak, Marietta, SC. Girl Scout Destinations are travel adventures, for individual girls ages 11 and older, that are inspiring, life-changing experiences. Destinations are determined via an application and review process by Girls Scouts of the USA. Girl Scout Stars also developed an Eclipse Activity Guide and kit box of materials, distributed the materials to 91 Girl Scout Councils, and delivered webinar training to councils. The eclipse materials enrich the girls' summer camp experiences with activities that promote understanding the Sun-Earth-Moon relationship, the solar system and safe eclipse viewing; and that feature science practices. Examples of the reach of the kit boxes are Girl Scouts of Montana and Wyoming Total Eclipse Event in Casper, WY, and the Girl Scouts of Northern California summer camps featuring the activities. In Girl Scouting, girls discover their skills, talents and what they care about; connect with other Girl Scouts and people in their community; and take action to change the world. This is called the Girl Scout Leadership Experience. With girl-led, hands on activities where girls can team up and work together

  12. The Gaugamela Battle Eclipse: An Archaeoastronomical Analysis

    NASA Astrophysics Data System (ADS)

    Polcaro, V. F.; Valsecchi, G. B.; Verderame, L.

    A total lunar eclipse occurred during the night preceding the decisive Battle of Gaugamela (20th September 331 BCE), when the Macedonian army, led by Alexander the Great, finally defeated the Persian king Darius and his army. This astronomical event, well known to historians, had a relevant role on the battle outcome. The eclipse was described in detail by Babylonian astronomers, though, unfortunately, the text of their report has only partially been preserved. We have reconstructed the evolution of the phenomenon as it appeared to the observer in Babylonia, by using the positional astronomy code "Planetario V2.0". On the base of this reconstruction we suggest a number of integrations to the lost part of the text, allowing a finer astrological interpretation of the eclipse and of its influence on the mood of the armies that set against each other on the following morning.

  13. RR Lyrae stars in eclipsing systems -- historical candidates

    NASA Astrophysics Data System (ADS)

    Liška, J.; Skarka, M.; Hájková, P.; Auer, R. F.

    2016-03-01

    Discovery of binary systems among RR Lyrae stars belongs to challenges of present astronomy. So far, none of classical RR Lyrae stars was clearly confirmed, that it is a part of an eclipsing system. From this reason we studied two RR Lyrae stars, VX Her and RW Ari, in which changes assigned to eclipses were detected in sixties and seventies of the 20th century. In this paper our preliminary results based on analysis of new photometric measurements are presented as well as the results from the detailed analysis of original measurements. A new possible eclipsing system, RZ Cet was identified in the archive data. Our analysis rather indicates errors in measurements and reductions of the old data than real changes for all three stars.

  14. NASA's Terra Satellite Sees Shadows of Solar Eclipse

    NASA Image and Video Library

    2015-03-20

    During the morning of March 20, 2015, a total solar eclipse was visible from parts of Europe, and a partial solar eclipse from northern Africa and northern Asia. NASA's Terra satellite passed over the Arctic Ocean on March 20 at 10:45 UTC (6:45 a.m. EDT) and captured the eclipse's shadow over the clouds in the Arctic Ocean. Credit: NASA Goddard MODIS Rapid Response Team 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

  15. Detection of the Secondary Eclipse of Exoplanet HAT P-11b

    NASA Technical Reports Server (NTRS)

    Barry, R. K.; Deming, L. D.; Bakos, G.; Harrington, J.; Madhusudhan, N.; Noyes, R.; Seager, S.

    2010-01-01

    We have successfully conducted secondary eclipse observations of exoplanet HAT-P-11b using the Spitzer Space Telescope. HAT-P-11b was, until very recently, the smallest transiting extrasolar planet yet found and one of only two known exo-Neptunes. We observed the system at 3.6 microns for a period of 22 hours centered on the anticipated secondary eclipse time, to detect the eclipse and determine its phase. Having detected the secondary eclipse, we are at present making a more focused series of observations in both the 3.6 and 4.5 micron bands to fully characterize it. HAT-P-11b has a period of 4.8878 days, radius of 0.422 RJ, mass of 0.081 MJ and semi-major axis 0.053 AU. Measurements of the secondary eclipse will serve to clarify two key issues; 1) the planetary brightness temperature and the nature of its atmosphere, and 2) the eccentricity of its orbit, with implications for its dynamical evolution. A precise determination of the orbit phase for the secondary eclipse will also be of great utility for Kepler observations of this system at visible wavelengths.

  16. MM Herculis - An eclipsing binary of the RS CVn

    NASA Technical Reports Server (NTRS)

    Sowell, J. R.; Hall, D. S.; Henry, G. W.; Burke, E. W., Jr.; Milone, E. F.

    1983-01-01

    V, B and U differential photoelectric photometry has been obtained for the RS Canum Venaticorum-class eclipsing binary star MM Her, with the light outside the eclipse being Fourier-analyzed to study wave migration and amplitude. These, together with the mean light level of the system, have been monitored from 1976 through 1980. Observations within the eclipse have revealed eclipses to be partial, rather than total as previously thought. The geometric elements of the presently rectified light curve are forced on the pre-1980 light curves and found to be compatible. With these elements, and previously obtained double line radial velocity curves, new absolute dimensions of 1.18 solar masses and 1.58 solar radii are calculated for the hotter star and 1.27 solar masses and 2.83 solar radii for the cooler star. The plotting of color indices on the color-color curve indicates G2V and K2IV spectral types.

  17. FIRST DAUGHTER IVANKA TRUMP PARTICIPATES IN SOLAR ECLIPSE ACTIVITIES AT NATIONAL AIR AND SPACE MUSEUM

    NASA Image and Video Library

    2017-08-21

    On Monday, Aug. 21, First Daughter, Ivanka Trump participated in solar eclipse viewing and STEM (Science, Technology, Engineering, and Mathematics) educational activities hosted by the Smithsonian National Air and Space Museum in Washington, D.C.

  18. APSIDAL MOTION AND A LIGHT CURVE SOLUTION FOR 13 LMC ECCENTRIC ECLIPSING BINARIES

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

    Zasche, P.; Wolf, M.; Vraštil, J.

    2015-12-15

    New CCD observations for 13 eccentric eclipsing binaries from the Large Magellanic Cloud were carried out using the Danish 1.54 m telescope located at the La Silla Observatory in Chile. These systems were observed for their times of minimum and 56 new minima were obtained. These are needed for accurate determination of the apsidal motion. Besides that, in total 436 times of minimum were derived from the photometric databases OGLE and MACHO. The O – C diagrams of minimum timings for these B-type binaries were analyzed and the parameters of the apsidal motion were computed. The light curves of thesemore » systems were fitted using the program PHOEBE, giving the light curve parameters. We derived for the first time relatively short periods of the apsidal motion ranging from 21 to 107 years. The system OGLE-LMC-ECL-07902 was also analyzed using the spectra and radial velocities, resulting in masses of 6.8 and 4.4 M{sub ⊙} for the eclipsing components. For one system (OGLE-LMC-ECL-20112), the third-body hypothesis was also used to describe the residuals after subtraction of the apsidal motion, resulting in a period of about 22 years. For several systems an additional third light was also detected, which makes these systems suspect for triplicity.« less

  19. Eclipse - tow flight closeup and release

    NASA Technical Reports Server (NTRS)

    1998-01-01

    This clip, running 15 seconds in length, shows the QF-106 'Delta Dart' gear down, with the tow rope secured to the attachment point above the aircraft nose. First there is a view looking back from the C-141A, then looking forward from the nose of the QF-106, and finally a shot of the aircraft being released from the tow rope. NASA Dryden Flight Research Center, Edwards, California, supported a Kelly Space and Technology, Inc. (KST)/U.S. Air Force project known as Eclipse, which demonstrated a reusable tow launch vehicle concept. The purpose of the project was to demonstrate a reusable tow launch vehicle concept that had been conceived and patented by KST. Kelly Space obtained a contract with the USAF Research Laboratory for the tow launch demonstration project under the Small Business Innovation Research (SBIR) program. The USAF SBIR contract included the modifications to turn the QF-106 into the Experimental Demonstrator #1 (EXD-01), and the C141A aircraft to incorporate the tow provisions to link the two aircraft, as well as conducting flight tests. The demonstration consisted of ground and flight tests. These tests included a Combined Systems Test of both airplanes joined by a tow rope, a towed taxi test, and six towed flights. The primary goal of the project was demonstrating the tow phase of the Eclipse concept using a scaled-down tow aircraft (C-141A) and a representative aerodynamically-shaped aircraft (QF-106A) as a launch vehicle. This was successfully accomplished. On December 20, 1997, NASA research pilot Mark Stucky flew a QF-106 on the first towed flight behind an Air Force C-141 in the joint Eclipse project with KST to demonstrate a reusable tow launch vehicle concept developed by KST. Kelly Space and Technology hoped to use the data from the tow tests to validate a tow-to-launch procedure for reusable space launch vehicles. Stucky flew six successful tow tests between December 1997 and February 6, 1998. On February 6, 1998, the sixth and final towed

  20. Annular Solar Eclipse of 10 May 1994

    NASA Technical Reports Server (NTRS)

    Espenak, Fred; Anderson, Jay

    1993-01-01

    An annular eclipse of the Sun will be widely visible from the Western Hemisphere on 10 May 1994. The path of the Moon's shadow passes through Mexico, the United States of America, maritime Canada, the North Atlantic, the Azores and Morocco. Detailed predictions for this event are presented and include tables of geographic coordinates of the annular path, local circumstances for hundreds of cities, maps of the path of annular and partial eclipse, weather prospects, and the lunar limb profile.

  1. Eclipse prediction on the ancient Greek astronomical calculating machine known as the Antikythera Mechanism.

    PubMed

    Freeth, Tony

    2014-01-01

    The ancient Greek astronomical calculating machine, known as the Antikythera Mechanism, predicted eclipses, based on the 223-lunar month Saros cycle. Eclipses are indicated on a four-turn spiral Saros Dial by glyphs, which describe type and time of eclipse and include alphabetical index letters, referring to solar eclipse inscriptions. These include Index Letter Groups, describing shared eclipse characteristics. The grouping and ordering of the index letters, the organization of the inscriptions and the eclipse times have previously been unsolved. A new reading and interpretation of data from the back plate of the Antikythera Mechanism, including the glyphs, the index letters and the eclipse inscriptions, has resulted in substantial changes to previously published work. Based on these new readings, two arithmetical models are presented here that explain the complete eclipse prediction scheme. The first model solves the glyph distribution, the grouping and anomalous ordering of the index letters and the structure of the inscriptions. It also implies the existence of lost lunar eclipse inscriptions. The second model closely matches the glyph times and explains the four-turn spiral of the Saros Dial. Together, these models imply a surprisingly early epoch for the Antikythera Mechanism. The ancient Greeks built a machine that can predict, for many years ahead, not only eclipses but also a remarkable array of their characteristics, such as directions of obscuration, magnitude, colour, angular diameter of the Moon, relationship with the Moon's node and eclipse time. It was not entirely accurate, but it was an astonishing achievement for its era.

  2. Eclipse Prediction on the Ancient Greek Astronomical Calculating Machine Known as the Antikythera Mechanism

    PubMed Central

    Freeth, Tony

    2014-01-01

    The ancient Greek astronomical calculating machine, known as the Antikythera Mechanism, predicted eclipses, based on the 223-lunar month Saros cycle. Eclipses are indicated on a four-turn spiral Saros Dial by glyphs, which describe type and time of eclipse and include alphabetical index letters, referring to solar eclipse inscriptions. These include Index Letter Groups, describing shared eclipse characteristics. The grouping and ordering of the index letters, the organization of the inscriptions and the eclipse times have previously been unsolved. A new reading and interpretation of data from the back plate of the Antikythera Mechanism, including the glyphs, the index letters and the eclipse inscriptions, has resulted in substantial changes to previously published work. Based on these new readings, two arithmetical models are presented here that explain the complete eclipse prediction scheme. The first model solves the glyph distribution, the grouping and anomalous ordering of the index letters and the structure of the inscriptions. It also implies the existence of lost lunar eclipse inscriptions. The second model closely matches the glyph times and explains the four-turn spiral of the Saros Dial. Together, these models imply a surprisingly early epoch for the Antikythera Mechanism. The ancient Greeks built a machine that can predict, for many years ahead, not only eclipses but also a remarkable array of their characteristics, such as directions of obscuration, magnitude, colour, angular diameter of the Moon, relationship with the Moon’s node and eclipse time. It was not entirely accurate, but it was an astonishing achievement for its era. PMID:25075747

  3. Atmospheric boundary layer effects induced by the 20 March 2015 solar eclipse

    NASA Astrophysics Data System (ADS)

    Gray, Suzanne L.; Harrison, R. Giles

    2016-04-01

    The British Isles benefits from dense meteorological observation networks, enabling insights into the still-unresolved effects of solar eclipse events on the near-surface wind field. The near-surface effects of the solar eclipse of 20 March 2015 are derived through comparison of output from the Met Office's operational weather forecast model (which is ignorant of the eclipse) with data from two meteorological networks: the Met Office's land surface station (MIDAS) network and a roadside measurement network operated by Vaisala. Synoptic-evolution relative calculations reveal the cooling and increase in relative humidity almost universally attributed to eclipse events. In addition, a slackening of wind speeds by up to about 2 knots in already weak winds and backing in wind direction of about 20 degrees under clear skies across middle England are attributed to the eclipse event. The slackening of wind speed is consistent with the previously reported boundary layer stabilisation during eclipse events. Wind direction changes have previously been attributed to a large-scale `eclipse-induced cold-cored cyclone', mountain slope flows, and changes in the strength of sea breezes. A new explanation is proposed here by analogy with nocturnal wind changes at sunset and shown to predict direction changes consistent with those observed.

  4. Implications of the Secondary Eclipse of Exoplanet HAT-P-11b

    NASA Technical Reports Server (NTRS)

    Barry, Richard K.; Deming, L. D.; Bakos, G.; Harrington, J.; Madhusudhan, N.; Noyes, R.; Seager, S.

    2010-01-01

    We observed exoplanet HAT-P-11b and have successfully detected its secondary eclipse. We conducted observations using the Spitzer Space Telescope in the post-cryo mission at 3.6 microns for a period of 22 hours centered on the anticipated secondary eclipse time, to detect the eclipse and determine its phase. Having detected the secondary eclipse, we are at present making a more focused series of observations in both the 3.6 and 4.5 micron bands to fully characterize it. HAT-P-11b is one of only two known exo-Neptunes and has a period of 4.8878 days, radius of 0.422 RJ, mass of 0.081 MJ and semi-major axis 0.053 AU. Measurements of the secondary eclipse will serve to clarify two key issues; 1) the planetary brightness temperature and the nature of its atmosphere, and 2) the eccentricity of its orbit, with implications for its dynamical evolution. We discuss implications of these observations.

  5. What are the Perspectives of Indonesian Students to Japanese Ritual during Solar Eclipse?

    NASA Astrophysics Data System (ADS)

    Haristiani, N.; Rusli, A.; Wiryani, A. S.; Nandiyanto, A. B. D.; Purnamasari, A.; Sucahya, T. N.; Permatasari, N.

    2018-02-01

    In this globalization era, many people still believe the myths about solar eclipse. The myths about solar eclipse are different between one country or are to another. In this context, the aim of this study was to investigate the perspective of Indonesian students in viewing how the Japanese people face their believing myths in solar eclipse. This research also investigated the student belief on several mythical stories in Indonesia, their understanding of the Islamic view, and their knowledge based on science concept relating to the solar eclipse phenomenon. To understand the Indonesian students’ perspective about the solar eclipse myths in Japanese, we took a survey to Indonesian students which are studying Japanese culture and language. Based on the results, the Indonesian student think that there is no significant difference between Indonesian and Japanese people in facing the solar eclipse.

  6. Ionospheric response to the total solar eclipse in India on 22 July, 2009

    NASA Astrophysics Data System (ADS)

    Chauhan, Vishal; Agrawal, Shikha; Singh, O. P.; Singh, Birbal

    2010-10-01

    Since The variations of Total Electron Content (TEC) and amplitude of the fixed frequency VLF transmitter signal (f = 19.8 kHz, NWC, Australia) are studied at Agra (Geographic Lat. 27.2°N, Long. 78°E), India during the total solar eclipse of 22 July, 2009 which was longest seen in India ever since 18 August, 1968. The equipment used for the study are a dual frequency GPS receiver (GSV 4004V) and a Soft PAL (Software based phase and amplitude logger) receiver. The data for a period of fifteen days (+/-7 days from the date of the event) are analysed and it is found that the TEC decreased by about 30% from normal days during the total solar eclipse, and the amplitude of the VLF signal also decreased likewise. The period of the data analysis is characterised by a low level of geomagnetic activity, hence the decrease in TEC and amplitude of the VLF signal is unlikely to be influenced by geomagnetic disturbances. The results are interpreted in terms of depression in electron densities at all ionospheric heights and are consistent with those obtained by earlier workers during similar eclipse events.

  7. Radial Velocities of 41 Kepler Eclipsing Binaries

    NASA Astrophysics Data System (ADS)

    Matson, Rachel A.; Gies, Douglas R.; Guo, Zhao; Williams, Stephen J.

    2017-12-01

    Eclipsing binaries are vital for directly determining stellar parameters without reliance on models or scaling relations. Spectroscopically derived parameters of detached and semi-detached binaries allow us to determine component masses that can inform theories of stellar and binary evolution. Here we present moderate resolution ground-based spectra of stars in close binary systems with and without (detected) tertiary companions observed by NASA’s Kepler mission and analyzed for eclipse timing variations. We obtain radial velocities and spectroscopic orbits for five single-lined and 35 double-lined systems, and confirm one false positive eclipsing binary. For the double-lined spectroscopic binaries, we also determine individual component masses and examine the mass ratio {M}2/{M}1 distribution, which is dominated by binaries with like-mass pairs and semi-detached classical Algol systems that have undergone mass transfer. Finally, we constrain the mass of the tertiary component for five double-lined binaries with previously detected companions.

  8. Baily's Beads Atlas in 2005 - 2008 Eclipses

    NASA Astrophysics Data System (ADS)

    Sigismondi, C.; Dunham, D. W.; Guhl, K.; Andersson, S.; Bode, H.; Canales, O.; Colona, P.; Farago, O.; Fernández-Ocaña, M.; Gabel, A.; Haupt, M.; Herold, C.; Nugent, R.; Oliva, P.; Patel, M.; Perello, C.; Rothe, W.; Rovira, J.; Schaefer, T.; Schnabel, C.; Schwartz, D.; Selva, A.; Strickling, W.; Tegtmeier, A.; Tegtmeier, C.; Thome, B.; Warren, W. H.

    2009-09-01

    In the annular or total eclipses of 3 October 2005, 29 March 2006, 22 September 2006, and 1 August 2008, observational campaigns were organized to record the phenomenon of Baily’s beads. These campaigns were internationally coordinated through the International Occultation Timing Association (IOTA) at both its American and European sections. From the stations in the northern and southern zones of grazing eclipse, the eclipses have been recorded on video. Afterward, as many beads as possible have been identified by analyzing the video data of each observing station. The atlas presented in this paper includes 598 data points, obtained by 23 observers operating at 28 different observing stations. The atlas lists the geographic positions of the observing stations and the observed time instants of disappearance or reappearance of beads, identified by an angle measured relative to the Moon’s axis of rotation. The atlas will serve as a basis for determining the solar diameter.

  9. An ultraviolet investigation of the unusual eclipsing binary system FF AQR

    NASA Technical Reports Server (NTRS)

    Dorren, J. D.; Guinan, E. F.; Sion, E. M.

    1982-01-01

    A series of seven low dispersion IUE exposures in ultraviolet and wavelength regions obtained on December 6, 1981 during the eclipse of the subdwarf, during egress, and out of eclipse is analyzed. These observations and the binary phase at which they were made are shown on a schematic representation of the V-band light curve obtained in 1975. The depth in V is 0.15 mag. The circles are IUE V magnitudes from FES measures obtained during the observing run. They indicate an eclipse depth some 0.05 mag lower than expected, possibly due to difficulties with the color term in the FES calibration. The eclipse depths of Dworetsky in U, B and V were assumed in the calculations.

  10. A Smoothed Eclipse Model for Solar Electric Propulsion Trajectory Optimization

    NASA Technical Reports Server (NTRS)

    Aziz, Jonathan D.; Scheeres, Daniel J.; Parker, Jeffrey S.; Englander, Jacob A.

    2017-01-01

    Solar electric propulsion (SEP) is the dominant design option for employing low-thrust propulsion on a space mission. Spacecraft solar arrays power the SEP system but are subject to blackout periods during solar eclipse conditions. Discontinuity in power available to the spacecraft must be accounted for in trajectory optimization, but gradient-based methods require a differentiable power model. This work presents a power model that smooths the eclipse transition from total eclipse to total sunlight with a logistic function. Example trajectories are computed with differential dynamic programming, a second-order gradient-based method.

  11. 2017 Total Eclipse Viewing Tips - Narrated by George Takei

    NASA Image and Video Library

    2017-08-09

    On Monday, August 21, 2017, all of North America will be treated to an eclipse of the sun. Anyone within the path of totality can see one of nature’s most awe inspiring sights - a total solar eclipse. This video, narrated by actor George Takei, provides a few viewing tips for the public.

  12. Simultaneous determination of carisoprodol and aspirin in human plasma using liquid chromatography-tandem mass spectrometry in polarity switch mode: application to a human pharmacokinetic study.

    PubMed

    Sreenivasulu, Vudagandla; Ramesh, Mullangi; Kumar, Inamadugu Jaswanth; Babu, Ravi Vasu; Pilli, Nageswara Rao; Krishnaiah, Abburi

    2013-02-01

    A simple, sensitive and rapid LC-MS/MS-ESI method has been developed and validated for simultaneous quantification of the carisoprodol and aspirin in human plasma. Carisoprodol was detected in positive ion mode, whereas aspirin was detected in negative ion mode. Carbamazepine and furosemide were used as internal standards (IS) for quantification of carisoprodol and aspirin, respectively. The extraction procedure involves a liquid-liquid extraction method with ter-butyl methyl ether. Chromatographic separation was achieved on a Zorbax XDB-Phenyl (4.6 × 75 mm, 3.5 µm) column using an isocratic mobile phase (5 mm ammonium acetate:methanol, 20:80, v/v) at a flow rate of 0.8 mL/min with a total run time of 2.2 min. A detailed method validation was performed as per the FDA guidelines. The standard curves found to be linear in the range of 25.5-4900 and 15.3-3000 ng/mL for carisoprodol and aspirin, respectively. The results met the acceptance criteria. Carisoprodol and aspirin were found to be stable in various stability studies. The validated method was successfully applied to a pharmacokinetic study following co-administration of carisoprodol (250 mg) and aspirin (75 mg) tablets by oral route to human volunteers. Copyright © 2012 John Wiley & Sons, Ltd.

  13. Earth Eclipses the Sun

    NASA Image and Video Library

    2017-12-08

    Twice a year, NASA’s Solar Dynamics Observatory, or SDO, has an eclipse season — a weeks-long period in which Earth blocks SDO’s view of the sun for part of each day. This footage captured by SDO on Feb. 15, 2017, shows one such eclipse. Earth’s edge appears fuzzy, rather than crisp, because the sun’s light is able to shine through Earth’s atmosphere in some places. These images were captured in wavelengths of extreme ultraviolet light, which is typically invisible to our eyes, but is colorized here in gold. Credit: NASA/Goddard/SDO 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

  14. Configuring Eclipse for GMAT Builds: Instructions for Windows Users, Rev. 0.3

    NASA Technical Reports Server (NTRS)

    Conway, Darrel J.

    2007-01-01

    This document provides instructions about how to configure the Eclipse IDE to build GMAT on Windows based PCs. The current instructions are preliminary; the Windows builds using Eclipse are currently a bit crude. These instructions are intended to give you enough information to get Eclipse setup to build wxWidgets based executables in general, and GMAT in particular.

  15. VizieR Online Data Catalog: OGLE eclipsing binaries in LMC (Wyrzykowski+, 2003)

    NASA Astrophysics Data System (ADS)

    Wyrzykowski, L.; Udalski, A.; Kubiak, M.; Szymanski, M.; Zebrun, K.; Soszynski, I.; Wozniak, P. R.; Pietrzynski, G.; Szewczyk, O.

    2003-09-01

    We present the catalog of 2580 eclipsing binary stars detected in 4.6 square degree area of the central parts of the Large Magellanic Cloud. The photometric data were collected during the second phase of the OGLE microlensing search from 1997 to 2000. The eclipsing objects were selected with the automatic search algorithm based on an artificial neural network. Basic statistics of eclipsing stars are presented. Also, the list of 36 candidates of detached eclipsing binaries for spectroscopic study and for precise LMC distance determination is provided. The full catalog is accessible from the OGLE Internet archive. (2 data files).

  16. Comparison of Ion Chemistries in Octafluoro-2-butene (2-C4F8) and in Octfluorocyclobutane (c-C4F8)

    NASA Astrophysics Data System (ADS)

    Jiao, Charles; Dejoseph, Charles; Garscadden, Alan

    2007-10-01

    2-C4F8 is one of the promising candidates to replace c-C4F8 that has been widely used for dielectric etching but is not environmentally friendly. In this study we have investigated electron impact ionization and ion-molecule reactions of 2-C4F8 using Fourier transform mass spectrometry (FTMS), and compared the results with those of c-C4F8 we have studied previously. Electron impact ionization of 2-C4F8 produces 15 ionic species including C4F7,8^+, C3F3,5,6^+, C2F4^+ and CF1-3^+ as the major ions. The total ionization cross section of 2-C4F8 reaches a maximum of 1.8x10-15 cm^2 at 90 eV. The ionization is dominated by the channel forming the parent ion C4F8^+ from 12 to 18 eV, and by the channel forming C3F5^+ from 18 to 70 eV. After 70 eV, CF3^+ becomes the dominant product ion. Among the major ions generated from the electron impact ionization of 2-C4F8, only CF^+, CF2^+ and CF3^+ are found to react with 2-C4F8, via F^- abstraction or charge transfer mechanism. The charge transfer reaction of Ar^++2-C4F8 produces primarily C4F7^+.

  17. Super Blood Moon Lunar Eclipse

    NASA Image and Video Library

    2017-12-08

    A preview animation of the Super Moon Lunar Eclipse On the evening of September 27, 2015 in the Americas (early morning on September 28 in Europe and most of Africa), the Moon enters the Earth’s shadow, creating a total lunar eclipse, the last of four visible in the Western Hemisphere in a span of 18 months. This animation shows the changing appearance of the Moon as it travels into and out of the Earth’s shadow. 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

  18. Monitoring a photovoltaic system during the partial solar eclipse of August 2017

    NASA Astrophysics Data System (ADS)

    Kurinec, Santosh K.; Kucer, Michal; Schlein, Bill

    2018-05-01

    The power output of a 4.85 kW residential photovoltaic (PV) system located in Rochester, NY is monitored during the partial solar eclipse of August 21, 2017. The data is compared with the data on a day before and on the same day, a year ago. The area of exposed solar disk is measured using astrophotography every 16 s of the eclipse. Global solar irradiance is estimated using the eclipse shading, time of the day, location coordinates, atmospheric conditions and panel orientation. A sharp decline, as expected in the energy produced is observed at the time of the peak of the eclipse. The observed data of the PV energy produced is related with the model calculations taking into account solar eclipse coverage and cloudiness conditions. The paper provides a cohesive approach of irradiance calculations and obtaining anticipated PV performance.

  19. 7Li(15N, 14C)8Be reaction at 81 MeV and 14C + 8Be interaction versus that of 13C + 8Be

    NASA Astrophysics Data System (ADS)

    Rudchik, A. T.; Rudchik, A. A.; Muravynets, L. M.; Kemper, K. W.; Rusek, K.; Koshchy, E. I.; Piasecki, E.; Trzcinska, A.; Pirnak, Val. M.; Ponkratenko, O. A.; Strojek, I.; Stolarz, A.; Plujko, V. A.; Sakuta, S. B.; Siudak, R.; Ilyin, A. P.; Stepanenko, Yu. M.; Shyrma, Yu. O.; Uleshchenko, V. V.

    2018-03-01

    Angular distributions of the 7Li(15N, 14C)8Be reaction were measured at the energy Elab(15N) = 81 MeV. Data for transfer to the ground and first two excited states in 8Be were acquired as well as to the 14C ground and excited states. The reaction data were analyzed within the coupled-reaction-channels (CRC) method. The required 15N + 7Li entrance channel potential was taken from the 15N + 7Li elastic scattering. The 14C + 8Be potential was found by fitting Woods-Saxon form potentials to those generated by double folded real and imaginary potentials in the region of interaction. These generated potentials were then used in the CRC calculations. Proton transfer dominants this reaction, including to the excited states of 8Be. The reaction dependence on the exit channel potential was examined by using the 13C + 8Be potential previously deduced from the 9Be(12C, 13C)8Be reaction and 14C + 8Be from the 13C(9Be, 8Be)14C reaction.

  20. What we learn from eclipsing binaries in the ultraviolet

    NASA Technical Reports Server (NTRS)

    Guinan, Edward F.

    1990-01-01

    Recent results on stars and stellar physics from IUE (International Ultraviolet Explorer) observations of eclipsing binaries are discussed. Several case studies are presented, including V 444 Cyg, Aur stars, V 471 Tau and AR Lac. Topics include stellar winds and mass loss, stellar atmospheres, stellar dynamos, and surface activity. Studies of binary star dynamics and evolution are discussed. The progress made with IUE in understanding the complex dynamical and evolutionary processes taking place in W UMa-type binaries and Algol systems is highlighted. The initial results of intensive studies of the W UMa star VW Cep and three representative Algol-type binaries (in different stages of evolution) focused on gas flows and accretion, are included. The future prospects of eclipsing binary research are explored. Remaining problems are surveyed and the next challenges are presented. The roles that eclipsing binaries could play in studies of stellar evolution, cluster dynamics, galactic structure, mass luminosity relations for extra galactic systems, cosmology, and even possible detection of extra solar system planets using eclipsing binaries are discussed.

  1. The Solar Eclipse Mural Series by Howard Russell Butler

    NASA Astrophysics Data System (ADS)

    Pasachoff, J. M.; Olson, R. J. M.

    2016-01-01

    There is a rich trove of astronomical phenomena in works of art by artists from the greater New York area, a trend that is even more pronounced in the oeuvres of New York City residents through the present day. A case in point is the trio of oil paintings by artist (and former physics professor) Howard Russell Butler depicting total solar eclipses in 1918, 1923, and 1925 that are based on his own observations. They were long displayed in the former art-deco building of the Hayden Planetarium of the American Museum of Natural History, the location of this conference. (The Museum also has nine other Butler paintings, none of which are currently exhibited.) Since the eclipse paintings have been in storage for many years, these once famous works are now virtually forgotten. Based on our research as an astronomer who has seen sixty-two solar eclipses and an art historian who has written extensively about astronomical imagery, we will discuss Butler's Solar Eclipse Triptych to explore its place in the history of astronomical imaging.

  2. Eclipse-induced wind changes over the British Isles on the 20 March 2015

    PubMed Central

    2016-01-01

    The British Isles benefits from dense meteorological observation networks, enabling insights into the still-unresolved effects of solar eclipse events on the near-surface wind field. The near-surface effects of the solar eclipse of 20 March 2015 are derived through comparison of output from the Met Office’s operational weather forecast model (which is ignorant of the eclipse) with data from two meteorological networks: the Met Office’s land surface station (MIDAS) network and a roadside measurement network operated by Vaisala. Synoptic-evolution relative calculations reveal the cooling and increase in relative humidity almost universally attributed to eclipse events. In addition, a slackening of wind speeds by up to about 2 knots in already weak winds and backing in wind direction of about 20° under clear skies across middle England are attributed to the eclipse event. The slackening of wind speed is consistent with the previously reported boundary layer stabilization during eclipse events. Wind direction changes have previously been attributed to a large-scale ‘eclipse-induced cold-cored cyclone’, mountain slope flows, and changes in the strength of sea breezes. A new explanation is proposed here by analogy with nocturnal wind changes at sunset and shown to predict direction changes consistent with those observed. This article is part of the themed issue ‘Atmospheric effects of solar eclipses stimulated by the 2015 UK eclipse’. PMID:27550759

  3. Suppression of the Polar Tongue of Ionization During the 21 August 2017 Solar Eclipse

    NASA Astrophysics Data System (ADS)

    Dang, Tong; Lei, Jiuhou; Wang, Wenbin; Burns, Alan; Zhang, Binzheng; Zhang, Shun-Rong

    2018-04-01

    It has long been recognized that during solar eclipses, the ionosphere-thermosphere system changes greatly within the eclipse shadow, due to the rapid reduction of solar irradiation. However, the concept that a solar eclipse impacts polar ionosphere behavior and dynamics as well as magnetosphere-ionosphere coupling has not been appreciated. In this study, we investigate the potential impact of the 21 August 2017 solar eclipse on the polar tongue of ionization (TOI) using a high-resolution, coupled ionosphere-thermosphere-electrodynamics model. The reduction of electron densities by the eclipse in the middle latitude TOI source region leads to a suppressed TOI in the polar region. The TOI suppression occurred when the solar eclipse moved into the afternoon sector. The Global Positioning System total electron content observations show similar tendency of polar region total electron content suppression. This study reveals that a solar eclipse occurring at middle latitudes may have significant influences on the polar ionosphere and magnetosphere-ionosphere coupling.

  4. Total solar eclipse effects on VLF signals: Observations and modeling

    NASA Astrophysics Data System (ADS)

    Clilverd, Mark A.; Rodger, Craig J.; Thomson, Neil R.; Lichtenberger, János; Steinbach, Péter; Cannon, Paul; Angling, Matthew J.

    During the total solar eclipse observed in Europe on August 11, 1999, measurements were made of the amplitude and phase of four VLF transmitters in the frequency range 16-24 kHz. Five receiver sites were set up, and significant variations in phase and amplitude are reported for 17 paths, more than any previously during an eclipse. Distances from transmitter to receiver ranged from 90 to 14,510 km, although the majority were <2000 km. Typically, positive amplitude changes were observed throughout the whole eclipse period on path lengths <2000 km, while negative amplitude changes were observed on paths >10,000 km. Negative phase changes were observed on most paths, independent of path length. Although there was significant variation from path to path, the typical changes observed were ~3 dB and ~50°. The changes observed were modeled using the Long Wave Propagation Capability waveguide code. Maximum eclipse effects occurred when the Wait inverse scale height parameter β was 0.5 km-1 and the effective ionospheric height parameter H' was 79 km, compared with β=0.43km-1 and H'=71km for normal daytime conditions. The resulting changes in modeled amplitude and phase show good agreement with the majority of the observations. The modeling undertaken provides an interpretation of why previous estimates of height change during eclipses have shown such a range of values. A D region gas-chemistry model was compared with electron concentration estimates inferred from the observations made during the solar eclipse. Quiet-day H' and β parameters were used to define the initial ionospheric profile. The gas-chemistry model was then driven only by eclipse-related solar radiation levels. The calculated electron concentration values at 77 km altitude throughout the period of the solar eclipse show good agreement with the values determined from observations at all times, which suggests that a linear variation in electron production rate with solar ionizing radiation is reasonable

  5. The new eclipsing magnetic binary system E 1114 + 182

    NASA Technical Reports Server (NTRS)

    Biermann, P.; Schmidt, G. D.; Liebert, J.; Tapia, S.; Strittmatter, P. A.; West, S.; Stockman, H. S.; Kuehr, H.; Lamb, D. Q.

    1985-01-01

    A comprehensive analysis of E 1114 + 182, the first eclipsing AM Herculis binary system and the shortest-period eclipsing cataclysmic variable known, is presented. The time-resolved X-ray observations which led to the system's recognition as an AM Her system with a roughly 90 minute orbital period are reported. The current optical photometric and polarimetric ephemeris and a description of the system's phase-modulated properties are given. The detailed photometric eclipse profile and the highly variable spectroscopic behavior are addressed. This information is used to determine systemic parameters and derive new information on the line emission regions. The data put severe constraints on current torque models for keeping the binary and white dwarf rotation in phase.

  6. Martian Eclipses: Deimos and Phobos

    NASA Image and Video Library

    2004-03-08

    The panoramic camera on NASA Opportunity combines the first photographs of solar eclipses by Mars two moons, Deimos and Phobos. Deimos appears as a speck in front of the Sun and Phobos grazes its edge.

  7. NASA in Silicon Valley Uses Eclipses to Study Our Galaxy

    NASA Image and Video Library

    2017-08-11

    The August 2017 total solar eclipse seen across the United States was an epic event. However, scientists and researchers at NASA's Ames Research Center use different types of eclipses every day to learn about the mysteries of our sun and our galaxy!

  8. A Dosimetric Evaluation of The Eclipse and Pinnacle Treatment Planning Systems in Treatment of Vertebral Bodies Using IMRT and VMAT with Modeled and Commissioned Flattening Filter Free (FFF) Fields

    NASA Astrophysics Data System (ADS)

    Ajo, Ramzi, Jr.

    Modern treatment planning systems (TPS's) utilize different algorithms in computing dose within the patient medium. The algorithms rely on properly modeled clinical setups in order to perform optimally. Aside from various parameters of the beam, modifiers, such as multileaf collimators (MLC's), must also be modeled properly. That could not be more true today, where dynamic delivery such as intensity modulated radiation therapy (IMRT) and volumetric modulated arc therapy (VMAT) are being increasingly utilized due to their ability to deliver higher dose precisely to the target while sparing more surrounding normal tissue. Two of the most popular TPS's, Pinnacle (Philips) and Eclipse (Varian), were compared, with special emphasis placed on parameterization of the dosimetric leaf gap (DLG) in Eclipse. The DLG is a parameter that accounts for Varian's rounded MLC leaf ends. While Pinnacle accounts for the rounded leaf end by modeling the MLC's, Eclipse uses a measured parameter. This study investigated whether a single value measured DLG is sufficient for dynamic delivery. Using five planning volumes for vertebral body SBRT treatments, each prescribed for 3000 cGy in 5 fractions, an array of 20 treatment plans was generated using varying energies of 6MV-FFF and 10MV-FFF. Treatment techniques consisted of 9-field Step-and-shoot IMRT, and dual-arc VMAT using patient specific optimization criteria in the Pinnacle TPS v9.8. Each plan was normalized to ensure coverage of 3000cGy to 95% of the target volume. The dose was computed in Pinnacle v9.8, with the Collapsed Cone Convolution Superposition algorithm and Eclipse v11, with the Acuros XB algorithm, using a dose grid resolution of 2 mm in both systems. Dose volume histograms (DVH's) were generated for a comparison of max and mean dose to the targets and spinal cord, as well as 95% coverage of the targets and the volume of the spinal cord receiving 14.5 Gy (V14.5). Patient specific quality assurance (PSQA) fields were

  9. Solar eclipses at high latitudes: ionospheric effects in the lower ionosphere

    NASA Astrophysics Data System (ADS)

    Cherniakov, S.

    2017-12-01

    The partial reflection facility of the Polar Geophysical Institute (the Tumanny observatory, 69.0N, 35.7E) has observed behavior of the high-latitude lower ionosphere during the 20 March 2015 total solar eclipse. There were several effects during the eclipse. At the heights of 60-80 km the ionosphere has shown the effect of a "short night", but at the higher altitudes local enhanced electron concentration had a wave-like form. Data received by the riometer of the Tumanny observatory have also shown wave-like behavior. The behavior can be explained by influence of acoustic-gravity waves which originated after cooling of the atmosphere during the lunar shadow supersonic movement, and transport processes during the eclipse. During the 21 August 2017 solar eclipse there was a substorm at the high latitudes. But after the end of the substorm in the region of the Tumanny observatory the observed amplitudes of the reflected waves had wave effects which could be connected with the coming waves from the region of the eclipse. The wave features were also shown in the behavior of the total electron content (TEC) of the lower ionosphere. During several solar eclipses it was implemented observations of lower ionosphere behavior by the partial reflection facility of the Tumanny observatory. The consideration of the lower ionosphere TEC had revealed common features in the TEC behavior during the eclipses. The photochemical theory of processes in the lower ionosphere is very complicated and up to now it is not completely developed. Therefore introduction of the effective coefficients determining the total speed of several important reactions has been widely adopted when modeling the D-region of the ionosphere. However, experimental opportunities for obtaining effective recombination coefficients are rather limited. One of the methods to estimate effective recombination coefficients uses the phenomenon of a solar eclipse. During solar eclipses at the partial reflection facility of

  10. Eclipse Across America: Through the Eyes of NASA

    NASA Astrophysics Data System (ADS)

    Young, C. Alex; Heliophysics Education Consortium

    2018-01-01

    Monday, August 21, 2017, marked the first total solar eclipse to cross the continental United States coast-to-coast in almost a century. NASA scientists and educators, working alongside many partners, were spread across the entire country, both inside and outside the path of totality. Like many other organizations, NASA prepared for this eclipse for several years. The August 21 eclipse was NASA's biggest media event in recent history, and was made possible by the work of thousands of volunteers, collaborators and NASA employees. The agency supported science, outreach, and media communications activities along the path of totality and across the country. This culminated in a 3 ½-hour broadcast from Charleston, SC, showcasing the sights and sounds of the eclipse – starting with the view from a plane off the coast of Oregon and ending with images from the International Space Station as the Moon's inner shadow left the US East Coast. Along the way, NASA shared experiments and research from different groups of scientists, including 11 NASA-supported studies, 50+ high-altitude balloon launches, and 12 NASA and partner space-based assets. This talk shares the timeline of this momentous event from NASA's perspective, describing outreach successes and providing a glimpse at some of the science results available and yet to come.

  11. Spectral changes in the zenith skylight during total solar eclipses.

    PubMed

    Hall, W N

    1971-06-01

    The relative spectral intensity of the zenith sky was measured with an optical scanning spectrometer at Nantucket Island, Massachusetts, during the total solar eclipse of 7 March 1970. The spectral ratios I(5100 A)/I(4300 A) and I(5900 A)/I(5100 A) at Nantucket remained unchanged for 96% or less obscuration of the sun by the moon. The results are compared with other recent relative spectral intensity measurements made during total solar eclipses. Comparison with other eclipse measurements for solar elevation angle at totality less than 45 degrees shows a blue color shift consistent with rayleigh scattering. Eclipses with solar elevation angles at totality greater than 45 degrees do not show consistent color shifts. This inconsistency may be due to difficulty in establishing a suitable reference spectrum for comparison with the spectral distribution of the zenith sky at totality. Selection of a suitable reference spectrum is discussed.

  12. The Planetary and Eclipse Oil Paintings of Howard Russell Butler

    NASA Astrophysics Data System (ADS)

    Pasachoff, Jay M.; Olson, R. M.

    2013-10-01

    The physics-trained artist Howard Russell Butler (1856-1934) has inspired many astronomy students through his planetary and eclipse paintings that were long displayed at the Hayden Planetarium in New York, the Fels Planetarium at the Franklin Institute in Philadelphia, and the Buffalo Museum of Science. We discuss not only the eclipse triptychs (1918, 1923, and 1925) at each of those institutions but also his paintings of Mars as seen from Phobos and from Deimos (with landscapes of those moons in the foreground depicted in additional oils hung at Princeton University) and the Earth from our Moon. We also describe his involvement with astronomy and his unique methodology that allowed him to surpass the effects then obtainable with photography, as well as his inclusion in a U.S. Naval Observatory eclipse expedition in 1918, as well as his auroral, solar-prominence, and 1932-eclipse paintings.

  13. Lunar eclipse photometry: absolute luminance measurements and modeling.

    PubMed

    Hernitschek, Nina; Schmidt, Elmar; Vollmer, Michael

    2008-12-01

    The Moon's time-dependent luminance was determined during the 9 February 1990 and 3 March 2007 total lunar eclipses by using calibrated, industry standard photometers. After the results were corrected to unit air mass and to standard distances for both Moon and Sun, an absolute calibration was accomplished by using the Sun's known luminance and a pre-eclipse lunar albedo of approximately 13.5%. The measured minimum level of brightness in the total phase of both eclipses was relatively high, namely -3.32 m(vis) and -1.7 m(vis), which hints at the absence of pronounced stratospheric aerosol. The light curves were modeled in such a way as to let the Moon move through an artificial Earth shadow composed of a multitude of disk and ring zones, containing a relative luminance data set from an atmospheric radiative transfer calculation.

  14. Interpretation of Historically Significant Solar and Lunar Eclipses

    NASA Astrophysics Data System (ADS)

    Muradyan, Armine; Mickaelian, A. M.

    2016-12-01

    Most of the ancient civilizations reacted with great awe and fear to the phenomena occurring in the sky and their changes. Periodically recurring movements of the Sun and the Moon attracting the attention of the astronomers, have given possibility to ancient civilizations to develop various calendars, including quite complicated ones. Since ancient times, Lunar and Solar eclipses were also among the forecasted phenomena, which have played an important role in human history. In the modern era, due to the cooperation of astronomers and historians, precise historical years and dates have been identified and the most important scientific discoveries of mankind have been proved with the help of eclipses. Most important historical Solar and Lunar eclipses, their impact on people, societies, history and science are presented and the interpretation of available to us historical events is given in this article.

  15. Changes of atmospheric properties over Belgrade, observed using remote sensing and in situ methods during the partial solar eclipse of 20 March 2015

    NASA Astrophysics Data System (ADS)

    Ilić, L.; Kuzmanoski, M.; Kolarž, P.; Nina, A.; Srećković, V.; Mijić, Z.; Bajčetić, J.; Andrić, M.

    2018-06-01

    Measurements of atmospheric parameters were carried out during the partial solar eclipse (51% coverage of solar disc) observed in Belgrade on 20 March 2015. The measured parameters included height of the planetary boundary layer (PBL), meteorological parameters, solar radiation, surface ozone and air ions, as well as Very Low Frequency (VLF, 3-30 kHz) and Low Frequency (LF, 30-300 kHz) signals to detect low-ionospheric plasma perturbations. The observed decrease of global solar and UV-B radiation was 48%, similar to the solar disc coverage. Meteorological parameters showed similar behavior at two measurement sites, with different elevations and different measurement heights. Air temperature change due to solar eclipse was more pronounced at the lower measurement height, showing a decrease of 2.6 °C, with 15-min time delay relative to the eclipse maximum. However, at the other site temperature did not decrease; its morning increase ceased with the start of the eclipse, and continued after the eclipse maximum. Relative humidity at both sites remained almost constant until the eclipse maximum and then decreased as the temperature increased. The wind speed decreased and reached minimum 35 min after the last contact. The eclipse-induced decrease of PBL height was about 200 m, with minimum reached 20 min after the eclipse maximum. Although dependent on UV radiation, surface ozone concentration did not show the expected decrease, possibly due to less significant influence of photochemical reactions at the measurement site and decline of PBL height. Air-ion concentration decreased during the solar eclipse, with minimum almost coinciding with the eclipse maximum. Additionally, the referential Line-of-Sight (LOS) radio link was set in the area of Belgrade, using the carrier frequency of 3 GHz. Perturbation of the receiving signal level (RSL) was observed on March 20, probably induced by the solar eclipse. Eclipse-related perturbations in ionospheric D-region were detected

  16. MOC Views of Martian Solar Eclipses

    NASA Technical Reports Server (NTRS)

    1999-01-01

    -middle-right (Ascraeus Mons).

    Phobos and the smaller, more distant satellite, Deimos, were discovered in 1877 by Asaph Hall, an astronomer at the United States Naval Observatory in Washington, D.C. Hall had been hunting for martian satellites for some time, and was about to abandon the search when he was encouraged by his wife to continue. In honor of her role, the largest crater on Phobos was named Stickney, her maiden name. Phobos is a tiny, potato-shaped world that is only about 13 km by 11 km by 9 km (8 mi by 7 mi by 6 mi) in size.

    In 1912 Edgar Rice Burroughs published a story entitled 'Under the Moons of Mars' (printed in book form in 1917 as A Princess of Mars) in which he referred to the 'hurtling moons of Barsoom' (Barsoom being the 'native' word for Mars in the fictional account). Burroughs was inspired by the fact that Phobos, having an orbital period of slightly less than 8 hours, would appear from Mars to rise in the west and set in the east only five and a half hours later. (Despite Burroughs' phrase, the outer moon, Deimos, can hardly be said to 'hurtle' -- it takes nearly 60 hours to cross the sky from east to west, rising on one day and not setting again for over two more.)

    If you could stand on Mars and watch Phobos passing overhead, you would notice that this moon appears to be only about half the size of what Earth's Moon looks like when viewed from the ground. In addition, the Sun would seem to have shrunk to about 2/3 (or nearly 1/2) of its size as seen from Earth. Martian eclipses are therefore dark but not as spectacular as total solar eclipses on Earth can be. In compensation, the martian eclipses are thousands of times more common, occurring a few times a day somewhere on Mars whenever Phobos passes over the planet's sunlit side. Due to the changing geometry of the MGS orbit relative to that of Phobos, the shadow is actually seen in MOC global map images (like in the second figure above) about a dozen times a month.

    The shadow of Phobos was seen

  17. Selected results from the epsilon Aurigae eclipse campaign, and what lies ahead

    NASA Astrophysics Data System (ADS)

    Stencel, Robert E.

    2013-07-01

    The torrent of data generated during the 2009-2011 eclipse of the enigmatic binary, epsilon Aurigae, has provided abundant opportunity to test and refine the many ideas associated with this system. The UBVRIJH photometric light curves established times of ingress and egress, and also revealed that the differential color of the disk varied, relative to pre- or post- mid-eclipse phase. Inter-eclipse monitoring indicated secular variations suggestive of a rapidly evolving F supergiant star. Interferometric imaging decisively identified the eclipse-causing agent to be an opaque disk (CHARA+MIRC). Spectroscopy has shown that a hot source occupies the center of this disk (He I 10830A, Far-UV excess), that the disk exhibits substructure (K I 7699A) and may have an extended atmosphere (CHARA+VEGA), and that the disk is isotopically-enhanced in 13C (GNIRS) and in rare-earth elements during a third contact "still-stand" in the light curve, suggestive of a mass transfer stream. Polarimetry and spectro-polarimetry provided additional constraints on the F star atmospheric variation and the nature of the dust scattering in the disk. Numerical models of the disk are exploring its relationship to the wider class of transitional and debris-type disks, and how differential heating of the dust may reveal properties not otherwise detected spectroscopically. As the system moves to quadrature in coming years, continued observing opportunities will continue to exist. I am grateful for support from the estate of William Herschel Womble for astronomy at the University of Denver, which has made possible two decades of research on this star that otherwise has revealed its secrets only very slowly.

  18. Meteorological responses in the atmospheric boundary layer over southern England to the deep partial eclipse of 20 March 2015.

    PubMed

    Burt, Stephen

    2016-09-28

    A wide range of surface and near-surface meteorological observations were made at the University of Reading's Atmospheric Observatory in central southern England (latitude 51.441° N, longitude 0.938° W, altitude 66 m above mean sea level) during the deep partial eclipse on the morning of 20 March 2015. Observations of temperature, humidity, radiation, wind speed and direction, and atmospheric pressure were made by computerized logging equipment at 1 Hz, supplemented by an automated cloud base recorder sampling at 1 min intervals and a high-resolution (approx. 10 m vertical interval) atmospheric sounding by radiosonde launched from the same location during the eclipse. Sources and details of each instrumental measurement are described briefly, followed by a summary of observed and derived measurements by meteorological parameter. Atmospheric boundary layer responses to the solar eclipse were muted owing to the heavily overcast conditions which prevailed at the observing location, but instrumental records of the event documented a large (approx. 80%) reduction in global solar radiation, a fall in air temperature of around 0.6°C, a decrease in cloud base height, and a slight increase in atmospheric stability during the eclipse. Changes in surface atmospheric moisture content and barometric pressure were largely insignificant during the event.This article is part of the themed issue 'Atmospheric effects of solar eclipses stimulated by the 2015 UK eclipse'. © 2016 The Author(s).

  19. Analysis of 45-years of Eclipse Timings of the Hyades (K2 V+ DA) Eclipsing Binary V471 Tauri

    NASA Astrophysics Data System (ADS)

    Marchioni, Lucas; Guinan, Edward; Engle, Scott

    2018-01-01

    V471 Tau is an important detached 0.521-day eclipsing binary composed of a K2 V and a hot DA white dwarf star. This system resides in the Hyades star cluster located approximately 153 Ly from us. V471 Tau is considered to be the end-product of common-envelope binary star evolution and is currently a pre-CV system. V471 Tau serves as a valuable astrophysical laboratory for studying stellar evolution, white dwarfs, stellar magnetic dynamos, and possible detection of low mass companions using the Light Travel Time (LTT) Effects. Since its discovery as an eclipsing binary in 1970, photometry has been carried out and many eclipse timings have been determined. We have performed an analysis of the available photometric data available on V471 Tauri. The binary system has been the subject of analyses regarding the orbital period. From this analysis several have postulated the existence of a third body in the form of a brown dwarf that is causing periodic variations in the system’s apparent period. In this study we combine ground based data with photometry secured recently from the Kepler K2 mission. After detrending and phasing the available data, we are able to compare the changing period of the eclipsing binary system against predictions on the existence of this third body. The results of the analysis will be presented. This research is sponsored by grants from NASA and NSF for which we are very grateful.

  20. Repeatability and Accuracy of Exoplanet Eclipse Depths Measured with Post-cryogenic Spitzer

    NASA Astrophysics Data System (ADS)

    Ingalls, James G.; Krick, J. E.; Carey, S. J.; Stauffer, John R.; Lowrance, Patrick J.; Grillmair, Carl J.; Buzasi, Derek; Deming, Drake; Diamond-Lowe, Hannah; Evans, Thomas M.; Morello, G.; Stevenson, Kevin B.; Wong, Ian; Capak, Peter; Glaccum, William; Laine, Seppo; Surace, Jason; Storrie-Lombardi, Lisa

    2016-08-01

    We examine the repeatability, reliability, and accuracy of differential exoplanet eclipse depth measurements made using the InfraRed Array Camera (IRAC) on the Spitzer Space Telescope during the post-cryogenic mission. We have re-analyzed an existing 4.5 μm data set, consisting of 10 observations of the XO-3b system during secondary eclipse, using seven different techniques for removing correlated noise. We find that, on average, for a given technique, the eclipse depth estimate is repeatable from epoch to epoch to within 156 parts per million (ppm). Most techniques derive eclipse depths that do not vary by more than a factor 3 of the photon noise limit. All methods but one accurately assess their own errors: for these methods, the individual measurement uncertainties are comparable to the scatter in eclipse depths over the 10 epoch sample. To assess the accuracy of the techniques as well as to clarify the difference between instrumental and other sources of measurement error, we have also analyzed a simulated data set of 10 visits to XO-3b, for which the eclipse depth is known. We find that three of the methods (BLISS mapping, Pixel Level Decorrelation, and Independent Component Analysis) obtain results that are within three times the photon limit of the true eclipse depth. When averaged over the 10 epoch ensemble, 5 out of 7 techniques come within 60 ppm of the true value. Spitzer exoplanet data, if obtained following current best practices and reduced using methods such as those described here, can measure repeatable and accurate single eclipse depths, with close to photon-limited results.

  1. Amateur observations of solar eclipses and derivation of scientific data

    NASA Astrophysics Data System (ADS)

    Stoev, A. D.; Stoeva, P. V.

    2008-12-01

    This work presents the educational approach of using total solar eclipse occurrences as a scientific process learning aid. The work reviews the basic scientific aims and experiments included in the observational programs "Total solar eclipse 1999 and 2006" (Stoev, A., Kiskinova, N., Muglova, P. et al. Complex observational programme of the Yuri Gagarin Public Astronomical Observatory and STIL, BAS, Stara Zagora Department for the August 11, 1999 total solar eclipse, in: Total Solar Eclipse 1999 - Observational Programmes and Coordination, Proceedings, Recol, Haskovo, pp. 133-137, 1999a (in Bulgarian); Stoeva, P.V., Stoev, A.D., Kostadinov, I.N. et al. Solar Corona and Atmospheric Effects during the March 29, 2006 Total Solar Eclipse, in: 11th International Science Conference SOLAR-Terrestrial Influences, Sofia, November 24-25, pp. 69-72, 2005). Results from teaching and training the students in the procedures, methods and equipment necessary for the observation of a total solar eclipse (TSE) at the Yuri Gagarin Public Astronomical Observatory (PAO) in Stara Zagora, Bulgaria, as well as the selection process used in determining participation in the different observational teams are discussed. The final stages reveal the special methodology used to investigate the level of "pretensions", the levels of ambition displayed by the students in achieving each independent goal, and the setting of goals in context with their problem solving capabilities and information gathering abilities in the scientific observation process. Results obtained from the observational experiments are interpreted mainly in the following themes: Investigation of the structure of the white-light solar corona and evolution of separate coronal elements during the total phase of the eclipse; Photometry of the white-light solar corona and specific emission lines; Meteorological, actinometrical and optical atmospheric investigations; Astrometry of the Moon during the phase evolution of the eclipse and

  2. Determination of oral bioavailability of curcuminoid dispersions and nanoemulsions prepared from Curcuma longa Linnaeus.

    PubMed

    Lu, Pei Shan; Inbaraj, Baskaran Stephen; Chen, Bing Huei

    2018-01-01

    Curcuminoid from Curcuma longa Linnaeus has been demonstrated to be effective in anti-cancer and anti-inflammation. The objectives of the present study were to prepare curcuminoid dispersion and nanoemulsion from C. longa and determine their oral bioavailabilities in rats. After curcuminoid extraction using 99.5% ethanol, bisdemethoxycurcumin (BDMC), demethoxycurcumin (DMC) and curcumin were separated within 10 min by high-performance liquid chromatography using an Eclipse XDB-C18 column (Agilent, Palo Alto, CA, USA) and a gradient mobile phase of 0.1% aqueous formic acid and acetonitrile, with a flow rate of 1 mL min -1 , column temperature of 35 °C and detection wavelength of 425 nm. Curcuminoid nanoemulsion at a particle size of 12.1 nm and encapsulation efficiency 98.8% was prepared using lecithin, Tween 80 and water. A pharmacokinetic study in rats revealed that the parameters including T max , C max , t 1/2 and the area under the curve were higher for curcuminoid nanoemulsions than for curcuminoid dispersion at the same dose employed for gavage administration, whereas, for intravenous injection, an opposite trend was shown. The oral bioavailabilities of BDMC, DMC, curcumin and total curcuminoids in nanoemulsion and dispersion were 34.39 and 4.65%, 39.93 and 5.49%, 47.82 and 9.38%, and 46 and 8.7%, respectively. The results of the present study demonstrate a higher oral bioavailability after incorporation of curcuminoid into nanoemulsion, facilitating its application as a botanic drug. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  3. Ionospheric response over Europe during the solar eclipse of March 20, 2015

    NASA Astrophysics Data System (ADS)

    Hoque, Mohammed Mainul; Wenzel, Daniela; Jakowski, Norbert; Gerzen, Tatjana; Berdermann, Jens; Wilken, Volker; Kriegel, Martin; Sato, Hiroatsu; Borries, Claudia; Minkwitz, David

    2016-10-01

    The solar eclipse on March 20, 2015 was a fascinating event for people in Northern Europe. From a scientific point of view, the solar eclipse can be considered as an in situ experiment on the Earth's upper atmosphere with a well-defined switching off and on of solar irradiation. Due to the strong changes in solar radiation during the eclipse, dynamic processes were initiated in the atmosphere and ionosphere causing a measurable impact, for example, on temperature and ionization. We analyzed the behavior of total ionospheric ionization over Europe by reconstructing total electron content (TEC) maps and differential TEC maps. Investigating the large depletion zone around the shadow spot, we found a TEC reduction of up to 6 TEC units, i.e., the total plasma depletion reached up to about 50%. However, the March 20, 2015 eclipse occurred during the recovery phase of a strong geomagnetic storm and the ionosphere was still perturbed and depleted. Therefore, the unusual high depletion is due to the negative bias of up to 20% already observed over Northern Europe before the eclipse occurred. After removing the negative storm effect, the eclipse-induced depletion amounts to about 30%, which is in agreement with previous observations. During the solar eclipse, ionospheric plasma redistribution processes significantly affected the shape of the electron density profile, which is seen in the equivalent slab thickness derived by combining vertical incidence sounding (VS) and TEC measurements. We found enhanced slab thickness values revealing, on the one hand, an increased width of the ionosphere around the maximum phase and, on the other, evidence for delayed depletion of the topside ionosphere. Additionally, we investigated very low frequency (VLF) signal strength measurements and found immediate amplitude changes due to ionization loss at the lower ionosphere during the eclipse time. We found that the magnitude of TEC depletion is linearly dependent on the Sun's obscuration

  4. Solar Eclipse 2017

    NASA Image and Video Library

    2017-08-21

    A partial eclipse on Florida's Space Coast, the rare astronomical event was photographed from the top of the Vehicle Assembly Building, as the Moon passed between Earth and the midafternoon Sun. The Moon's shadow moved across the landscape from Oregon to South Carolina. The 70-mile-wide totality path, or "umbral cone" -- where the entire Sun will vanish behind the Moon -- stretched across 14 states, from Oregon to South Carolina.

  5. Super Blood Moon Lunar Eclipse

    NASA Image and Video Library

    2017-12-08

    What time will you be able to view the Super Moon Eclipse? The images below show times to view it for Eastern Daylight Time (EDT), Central Daylight Time (CDT), Mountain Daylight Time (MDT) and Pacific Daylight Time (PDT). All of South America and most of North and Central America will see the entire eclipse, while those west of roughly 120°W will see it in progress at moonrise. You won’t need special equipment to see it. Just go outside and look up! 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

  6. Building on the US Eclipse Experience in Schools, with the Public, and Beyond the US

    NASA Astrophysics Data System (ADS)

    Simmons, Mike; Chee, Zoe; Bartolone, Lindsay

    2018-01-01

    Astronomers Without Borders (AWB) organized several programs for the August 21, 2017 total solar eclipse, both before and after the event, to increase participation, build on the inspiration of the eclipse, share the eclipse experience, and prepare for the eclipse in 2024.AWB focused on preparing institutions that were least likely to receive resources despite extensive nationwide efforts. AWB distributed more than 100,000 donated glasses, to isolated schools, children's cancer hospitals, abused women’s shelters, and other institutions without access to other resource providers.AWB’s Building on the Eclipse Education Program builds on the inspiration of the eclipse for STEM education. The program uses a small, personal spectroscope kit to study sunlight in different scientific fields and includes free classroom activities that meet NGSS standards.A program to collect eclipse observing glasses for schools in developing countries for future eclipses was announced around the time of the eclipse and quickly went viral, with coverage by national and innumerable local media outlets. This effort builds on AWB’s earlier programs for schools in Africa and in South America for past eclipses. Well over one million pairs are expected, as compared to the tens of thousands AWB provided through crowdfunding for previous efforts. Nearly 1000 glasses collection centers were created spontaneously, without a public call. Factors leading to widespread and diverse public participation will be presented.A program calling for first-time eclipse observers to share their experiences addresses a major issue in encouraging people to travel to the path of totality. Expert and eclipse-enthusiast testimony often fails to convince people of the value of the experience of totality as “a few minutes of darkness.” This program will share the disconnect between expectation and experience from first-time “ordinary” observers to encourage others to travel to the path of totality for the

  7. The Trojan war dated by two solar eclipses.

    NASA Astrophysics Data System (ADS)

    Henriksson, Goran

    The Trojan War was very significant for the ancient Greeks and they dated historical events according to the number of years after the fall of Troy. However, there was already in antiquity no consensus as to the exact date of the war when compared with different epochs. Even after the modern discovery of the ancient city, there has been disagreement among different excavators as to which layer corresponds to the city mentioned in the Iliad attributed to Homer. In this paper an attempt is made to identify the strange obscuration of the sun that occurred during the final battle of the Iliad as a total solar eclipse close to the southern border of the zone of totality. There exists only one solar eclipse that corresponds to the description in the text and this is the total solar eclipse of June 11, in 1312 BC. When I first presented this date in 1986, there was a difference of about 60 years compared with the most common archaeological dating at that time. My date is now fully supported by the latest results from the German-American excavation that identifies the fall of Homer's Troy with the destruction of the archaeological layer Troy VIh, dated to about 1300 BC. Further independent support is provided by another solar eclipse that dates the reign of the Hittite king Muwatalli II. This king wrote a letter to king Alaksandu in Wilusa, identified as the Hittite name for Ilios, the most frequently used name for Troy in the Iliad. Alexander was another name for Paris who abducted Helen, the crime that resulted in the war. Muwatalli II was king 1315-1297 BC, according to the chronology for the Hittite Kingdom based on a solar eclipse in 1335 BC, during the tenth year of King Mursili II (1345- 1315 BC), the father of Muwatalli II.

  8. Eclipse project closeup of QF-106 under tow on first tethered flight December 20, 1997

    NASA Technical Reports Server (NTRS)

    1997-01-01

    The Kelly Space and Technology (KST)/USAF/NASA Eclipse project's modified QF-106 is shown under tow on the project's first tethered flight on December 20, 1997. The successful 18-minute-long flight reached an altitude of 10,000 feet. NASA's Dryden Flight Research Center, Edwards, California, is hosting the project, providing engineering and facility support as well as the project pilot, Mark Stucky. In 1997 and 1998, the Dryden Flight Research Center at Edwards, California, supported and hosted a Kelly Space & Technology, Inc. project called Eclipse, which sought to demonstrate the feasibility of a reusable tow-launch vehicle concept. The project goal was to successfully tow, inflight, a modified QF-106 delta-wing aircraft with an Air Force C-141A transport aircraft. This would demonstrate the possibility of towing and launching an actual launch vehicle from behind a tow plane. Dryden was the responsible test organization and had flight safety responsibility for the Eclipse project. Dryden provided engineering, instrumentation, simulation, modification, maintenance, range support, and research pilots for the test program. The Air Force Flight Test Center (AFFTC), Edwards, California, supplied the C-141A transport aircraft and crew and configured the aircraft as needed for the tests. The AFFTC also provided the concept and detail design and analysis as well as hardware for the tow system and QF-106 modifications. Dryden performed the modifications to convert the QF-106 drone into the piloted EXD-01 (Eclipse eXperimental Demonstrator-01) experimental aircraft. Kelly Space & Technology hoped to use the results gleaned from the tow test in developing a series of low-cost, reusable launch vehicles. These tests demonstrated the validity of towing a delta-wing aircraft having high wing loading, validated the tow simulation model, and demonstrated various operational procedures, such as ground processing of in-flight maneuvers and emergency abort scenarios.

  9. Periodic Eclipse Variations in Asynchronous Polar V1432 Aql: Evidence of a Shifting Threading Region

    NASA Technical Reports Server (NTRS)

    Littlefield, Colin; Mukai, Koji; Mumme, Raymond; Cain, Ryan; Magno, Katrina C.; Corpuz, Taylor; Sandefur, Davis; Boyd, David; Cook, Michael; Ulowetz, Joseph; hide

    2015-01-01

    We report the results of a 28-month photometric campaign studying V1432 Aql, the only known eclipsing, asynchronous polar. Our data show that both the residual eclipse flux and eclipse O-C timings vary strongly as a function of the spin-orbit beat period. Relying upon a new model of the system, we show that cyclical changes in the location of the threading region along the ballistic trajectory of the accretion stream could produce both effects. This model predicts that the threading radius is variable, in contrast to previous studies which have assumed a constant threading radius. Additionally, we identify a very strong photometric maximum which is only visible for half of the beat cycle. The exact cause of this maximum is unclear, but we consider the possibility that it is the optical counterpart of the third accreting polecap proposed by Rana et al. Finally, the rate of change of the white dwarf's spin period is consistent with it being proportional to the difference between the spin and orbital periods, implying that the spin period is approaching the orbital period asymptotically.

  10. Analysis of ionospheric irregularities during total solar eclipse 2016 based on GNSS observation

    NASA Astrophysics Data System (ADS)

    Husin, A.; Jiyo; Anggarani, S.; Ekawati, S.; Dear, V.

    2016-11-01

    A total solar eclipse occurred over Indonesia in the morning hours on 9 March 2016. Ionisations in the ionosphere which is associated with the solar radiation during the total eclipse provided a good opportunity to study the ionospheric irregularities. Using global navigation satellite system (GNSS) data taken from dual-frequency receivers in Manado, we investigated and analysed the total electron content (TEC) perturbations with a time resolution of 60 s to reveal ionospheric irregularities during total eclipse. Result showed that TEC conditions based on IPP were decreased during solar eclipse on March 9, comparing with the neighbour day. The maximum percentage deviation (DTEC) from the average value during eclipse period, 00:00 - 02:40 UT reach -41.5%. The duration of maximum decrement in TEC occurs were around 2-30 minutes after the maximum obscuration.

  11. A Photometric Study of the Eclipsing Binary Star PY Boötis

    NASA Astrophysics Data System (ADS)

    Michaels, E. J.

    2016-12-01

    Presented here are the first precision multi-band CCD photometry of the eclipsing binary star PY Boötis. Best-fit stellar models were determined by analyzing the light curves with the Wilson-Devinney program. Asymmetries in the light curves were interpreted as resulting from magnetic activity which required spots to be included in the model. The resulting model is consistent with a W-type contact eclipsing binary having total eclipses.

  12. What If It Rains on Your Eclipse? Planning Ahead for August 2017

    NASA Astrophysics Data System (ADS)

    Bartlett, Jennifer L.; Keohane, J.

    2010-01-01

    It was a dark and rainy morning, not far out of Shanghai, when we saw the 2009 July 22 total solar eclipse. Many of the Americans puttering around their equipment that morning, in hopes that the sky would clear enough to catch some of event they had traveled around the world to view, were already planning ahead for 2017 August 21, when a narrow strip of the United States will experience up to 2 minutes and 45 seconds of totality. For most people, a total solar eclipse is once in a lifetime event steeped in legend. If you are situated along this privileged corridor, you will have a wonderful opportunity for public outreach. But what if it rains? Historically, August is mostly sunny at the location of greatest eclipse, near Makanda, Illinois. Even with such favorable circumstances, having a rain plan will ensure you make the most of the occasion. First, the flexibility to relocate your program to take advantage of the most favorable weather would be ideal. If that is not a realistic option, include some protective gear with your equipment so that you can set up despite misty or drizzling conditions. Second, monitoring changing light levels and temperatures should be possible even under cloudy skies. Third, for some sites, changes in wildlife behavior may also be noticeable. If the weather is clear, such projects could enhance your program during the partial phases of the eclipse and provide enrichment materials for those unable to attend. While 2017 may still seem in the distant future to all but eclipse fanatics, some creativity and advance brainstorming will ensure that your outreach program shines during the event, even if the Sun does not cooperate. S. Bell (2009, pc.), HMNAO, provided the eclipse predictions. Additional information is available via USNO Eclipse Portal (http://www.eclipse.org.uk/eclbin/query_usno.cgi).

  13. Initial Results of HamSCI Ham Radio 21 August 2017 Eclipse Ionospheric Experiments

    NASA Astrophysics Data System (ADS)

    Frissell, N. A.; Gerrard, A. J.; Vega, J. S.; Katz, J. D.; West, M. L.; Gunning, S. W.; Moses, M. L.; Miller, E. S.; Erickson, P. J.; Huba, J.; Silver, H. W.; Ceglia, F.; Smith, P.; Williams, R.; Shovkoplyas, A.; Earle, G. D.; Gerzoff, R.; Gladstone, P.; Reyer, S. E.; Ackermann, J. R.; Bern, D.; Rose, S. W.

    2017-12-01

    On 21 August 2017, a total solar eclipse will cause the shadow of the moon to traverse the United States from Oregon to South Carolina in just over 90 minutes. The sudden absence of sunlight due to the eclipse, especially solar UV and x-rays, provides an impulse function to the upper atmosphere that modifies the neutral dynamics, plasma concentrations, and related properties. Despite more than 60 years of research, questions remain regarding eclipse-induced ionospheric impacts. Ham radio operators' advanced technical skills and inherent interest in ionospheric science make the amateur radio community ideal for contributing to and and participating in large-scale ionospheric sounding experiments. We present initial results from three amateur radio experiments designed to study the 2017 total solar eclipse: the Solar Eclipse QSO Party (SEQP), the HF Wideband Recording Experiment, and the Eclipse Frequency Measurement Test (FMT). These experiments are coordinated by HamSCI, the Ham Radio Science Citizen Investigation, a citizen science organization that connects the amateur radio community to the professional space science research community for mutual benefit.

  14. Teaching Science: Eclipse Seasons.

    ERIC Educational Resources Information Center

    Leyden, Michael B.

    1995-01-01

    Demonstrates the need for a three-dimensional model as an aid for teaching students why eclipses do not occur every two weeks, as falsely indicated by two-dimensional models such as books, chalkboards, and computer screens. Describes procedure to construct the model. Indicates question related to seasons likely to arise from such a model and…

  15. Reliability of the totality of the eclipse in AD 628 in Nihongi

    NASA Astrophysics Data System (ADS)

    Tanikawa, Kiyotaka; Soma, Mitsuru

    It is generally accepted that the solar eclipse on April 10, 628 (the second day, the third month, the thirty-sixth year of Empress Suiko) recorded in Nihongi is not total but partial though it is written as a total eclipse. We argue for the record appealing to the contemporary total or near total eclipses in Chinese history books and Japanese occultation observation. If the value of the tidal term in the lunar longitude (the coefficient of T2 term) is different from the present value by about -2"/cy-2, then there disappears an apparent contradiction of ΔT around AD 600 derived from lunar and solar eclipses. Grazing occultation data are found to be useful.

  16. [Survey of ocular injury by solar eclipse 2009].

    PubMed

    Obana, Akira; Takahashi, Jun; Ohnishi, Kouji; Shinohara, Hideo; Matsuo, Atsushi; Saito, Izumi; Ohkawa, Takuya; Ono, Tomoko

    2011-07-01

    Incidence of ocular injury caused by the solar eclipse of 2009 has been investigated using the questionnaire of the Japan Committee of the International Year of Astronomy 2009. The questionnaire was available to the public on the website. Answers were obtained from 14 people (12 men, 2 women), aged from sixteen to fifty-four. All had looked at the sun either with the naked eye or through some shading device (plastic sheet, plastic bag, compact disc, etc.) the safty of which is unknown. Reported symptoms included a sense of incongruity, heat, pain, central scotoma or visual disturbance, classified into four periods of duration. Three people with transient symptoms watched the eclipse with the naked eye for one minute in cloudy weather. Three people with symptoms lasting for one day and three people with symptoms lasting for one week had watched it with the naked eye and some shading device for 10 minutes in cloudy weather. Five people with symptoms lasting for more than one week watched the eclipse with the naked eye and through some sort of device in fine or slightly cloudy weather. Three people consulted their ophthalmologist. Those who reported adverse symptoms did not comply with the instructions for safe watching of the eclipse and the duration of the symptoms depended on the weather and the type of device used.

  17. Total solar eclipse of 1995 October 24

    NASA Technical Reports Server (NTRS)

    Espenak, Fred; Anderson, Jay

    1994-01-01

    A total eclipse of the sun will be visible from Asia and the Pacific Ocean on 24 Oct. 1995. The path of the moon's shadow begins in the Middle East and sweeps across India, Southeast Asia, and the waters of the Indonesian archipelago before ending at sunset in the Pacific. Detailed predictions for this event are presented and include besselian elements, geographic coordinates of the path of totality, physical ephemeris of the umbra, topocentric limb profile corrections, local circumstances for 400 cities, maps of the eclipse path, weather prospects, the lunar limb profile, and the sky during totality.

  18. St. Benedict Sees the Light: Asam's Solar Eclipses as Metaphor

    NASA Astrophysics Data System (ADS)

    Olson, Roberta J. M.; Pasachoff, Jay M.

    During the Baroque period, artists worked in a style - encouraged by the Roman Catholic Church and the Council of Trent - that revealed the divine in natural forms and made religious experiences more accessible. Cosmas Damian Asam, painter and architect, and his brother Egid (Aegid) Quirin Asam, sculptor and stuccatore, were the principal exponents of eighteenth-century, southern-German religious decoration and architecture in the grand manner, the Gesamtkunstwerk. Cosmas Damian's visionary and ecstatic art utilized light, both physical and illusionistic, together with images of meteorological and astronomical phenomena, such as solar and lunar eclipses. This paper focuses on his representations of eclipses and demonstrates how Asam was galvanized by their visual, as well as metaphorical power and that he studied a number of them. He subsequently applied his observations in a series of paintings for the Benedictine order that become increasingly astronomically accurate and spiritually profound. From the evidence presented, especially in three depictions of St. Benedict's vision, the artist harnessed his observations to visualize the literary description of the miraculous event in the Dialogues of St. Gregory the Great, traditionally a difficult scene to illustrate, even for Albrecht Dürer. Asam painted the trio at Einsiedeln, Switzerland (1724-27); Kladruby, the Czech Republic (1725-27), where he captured the solar corona and the "diamond-ring effect"; and Weltenburg, Germany (1735), where he also depicted the diamond-ring effect at a total solar eclipse. We conclude that his visualizations were informed by his personal observations of the solar eclipses on 12 May 1706, 22 May 1724, and 13 May 1733. Asam may have also known the eclipse maps of Edmond Halley and William Whiston that were issued in advance. Astronomers did not start studying eclipses scientifically until the nineteenth century, making Asam's depictions all the more fascinating. So powerful was the

  19. The Eclipse Megamovie Tour: building awareness of the eclipse and gathering public support for the Megamovie Project

    NASA Astrophysics Data System (ADS)

    Peticolas, L. M.; Yan, D.; Cable, C.; Zevin, D.; Johnson, C.; Bender, M.

    2017-12-01

    The "Eclipse Megamovie" project aimed to gather scientifically useful photographs of the corona from the public at large during the Aug 21, 2017 total solar eclipse. The project used many different mechanisms for gathering 3 types of volunteers: the over 1,000 trained photographers positioned along the path of totality, members of the public along the path of totality using the Megamovie App, and members of the public who took photographs on their own and then uploaded photographs. In order to interest the public in becoming volunteers to provide photographs for this scientific effort, we drove across the path of totality providing presentations in a town hall fashion. We drove through nine states in week-long trips with a total of six trips. The first week took place in August, 2016 through Oregon. The remaining trips took place February-June, 2017. The tour gained press in each town seeded our recruitment efforts, which then gained momentum via articles and press releases in the Spring and Summer, 2017. By Aug 2, 2017 over 1,000 photographers had signed up to be trained volunteers. This presentation will present information on the tours and their impact in seeding the overall recruitment effort for the Eclipse Megamovie Project.

  20. Stellar background observation during Total Solar Eclipse March 9th 2016

    NASA Astrophysics Data System (ADS)

    Mumtahana, Farahhati; Timur Jaelani, Anton; Muhamad, Johan; Sutastio, Heri

    2016-11-01

    We report observation and an early analysis of stellar background from total solar eclipse in Ternate, Indonesia. The eclipse phenomena which occurred on March, 9th 2016 was observed with certain portable instruments in order to obtain the stars behind the Sun in particular field of view and resolution. From our observation site in Ternate city, solar eclipse occurred in the late morning when the weather was unfortunately cloudy. However, during the darkness of totality, we obtained several point source objects between the gaps of the moving clouds and we suspected them as very faint stars due to their appearance in several frames. Those so called stars have been identified and measured with respect to their positions toward the center of the Sun. The main purpose of this research is to revisit strong lensing calculation of the Sun during total solar eclipse by measuring the deflection angle of the background stars as it had been calculated by Einstein and proved by Eddington at a total solar eclipse in 1919. To accomplish this aim, we need to conduct another observation to measure position of the same stars in the next period when those stars appear in the night sky.

  1. [Development of a Software for Automatically Generated Contours in Eclipse TPS].

    PubMed

    Xie, Zhao; Hu, Jinyou; Zou, Lian; Zhang, Weisha; Zou, Yuxin; Luo, Kelin; Liu, Xiangxiang; Yu, Luxin

    2015-03-01

    The automatic generation of planning targets and auxiliary contours have achieved in Eclipse TPS 11.0. The scripting language autohotkey was used to develop a software for automatically generated contours in Eclipse TPS. This software is named Contour Auto Margin (CAM), which is composed of operational functions of contours, script generated visualization and script file operations. RESULTS Ten cases in different cancers have separately selected, in Eclipse TPS 11.0 scripts generated by the software could not only automatically generate contours but also do contour post-processing. For different cancers, there was no difference between automatically generated contours and manually created contours. The CAM is a user-friendly and powerful software, and can automatically generated contours fast in Eclipse TPS 11.0. With the help of CAM, it greatly save plan preparation time and improve working efficiency of radiation therapy physicists.

  2. Impact of the 2017 Solar Eclipse on the Smart Grid

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

    Habte, Aron M; Reda, Ibrahim M; Andreas, Afshin M

    With the increasing interest in using solar energy as a major contributor to the use of renewable generation, and with the focus on using smart grids to optimize the use of electrical energy based on demand and resources from different locations, the need arises to know the moons position in the sky with respect to the sun. When a solar eclipse occurs, the moon disk might totally or partially shade the sun disk, which can affect the irradiance level from the sun disk, consequently affecting a resource on the electric grid. The moons position can then provide smart grid usersmore » with information about how potential total or partial solar eclipses might affect different locations on the grid so that other resources on the grid can be directed to where they might be needed when such phenomena occurs. At least five solar eclipses occur yearly at different locations on Earth, they can last 3 hours or more depending on the location, and they can affect smart grid users. On August 21, 2017, a partial and full solar eclipse occurred in many locations in the United States, including at the National Renewable Energy Laboratory in Golden, Colorado. Solar irradiance measurements during the eclipse were compared to the data generated by a model for validation at eight locations.« less

  3. Howard Russell Butler's Oil Paintings of Solar Eclipses and Prominences

    NASA Astrophysics Data System (ADS)

    Pasachoff, Jay M.; Olson, Roberta J. M.

    2014-06-01

    Howard Russell Butler (1856-1934) was invited to join the US Naval Observatory expedition to the total solar eclipse of 1918 because of his ability to paint astronomical phenomena based on quickly-made notes about spatial and color details. His giant triptych of the total eclipses of 1918, 1923, and 1925 was proposed for a never-built astronomical center at the American Museum of Natural History and wound up at their Hayden Planetarium when it was constructed in the mid-1930s. Half-size versions are installed at the Fels Planetarium at the Franklin Institute in Philadelphia and at the Firestone Library of Princeton University, whose newly conserved canvases were recently hung; the Buffalo Museum of Science has another half-size version in storage. We discuss not only the eclipse triptychs but also the series of large oil paintings he made of solar prominences (in storage at the American Museum of Natural History) and of his 1932-eclipse and other relevant works.JMP was supported for this work in part by Division III Discretionary Funds and the Brandi Fund of Williams College. His current eclipse research is supported by grants AGS-1047726 from the Solar Research Program of the Atmospheric and Geospace Sciences Division of NSF and 9327-13 from the Committee for Research and Exploration of the National Geographic Society.

  4. The first eclipsing binary catalogue from the MOA-II data base

    NASA Astrophysics Data System (ADS)

    Li, M. C. A.; Rattenbury, N. J.; Bond, I. A.; Sumi, T.; Bennett, D. P.; Koshimoto, N.; Abe, F.; Asakura, Y.; Barry, R.; Bhattacharya, A.; Donachie, M.; Evans, P.; Freeman, M.; Fukui, A.; Hirao, Y.; Itow, Y.; Ling, C. H.; Masuda, K.; Matsubara, Y.; Muraki, Y.; Nagakane, M.; Ohnishi, K.; Saito, To.; Sharan, A.; Sullivan, D. J.; Suzuki, D.; Tristram, P. J.; Yonehara, A.

    2017-09-01

    We present the first catalogue of eclipsing binaries in two MOA (Microlensing Observations in Astrophysics) fields towards the Galactic bulge, in which over 8000 candidates, mostly contact and semidetached binaries of periods <1 d, were identified. In this paper, the light curves of a small number of interesting candidates, including eccentric binaries, binaries with noteworthy phase modulations and eclipsing RS Canum Venaticorum type stars, are shown as examples. In addition, we identified three triple object candidates by detecting the light-travel-time effect in their eclipse time variation curves.

  5. The Great American Eclipse of 2017: An Outreach Opportunity and Challenge

    NASA Astrophysics Data System (ADS)

    Fraknoi, A.; Schatz, D.; Shore, L.

    2015-11-01

    This paper consists of notes for, and from, a standing-room only Special Interest Group discussion at the 2014 ASP Meeting regarding the total eclipse of the Sun visible from the U.S. in 2017. There was a great deal of interest in organizing in advance for this total eclipse, and there was considerable discussion of the kinds of efforts and partnerships that may be needed at the national and local levels. People who read this summary and are interested in helping with national eclipse education and outreach efforts can contact the first author.

  6. EclipseMob: Results from a nation-wide citizen science experiment on the effects of the 2017 Solar Eclipse on Low-frequency (LF) Radio Propagation

    NASA Astrophysics Data System (ADS)

    Liles, W. C.; Lukes, L.; Nelson, J.; Henry, J.; Oputa, J.; Kerby-Patel, K. C.

    2017-12-01

    Early experiments to study the effects of a solar eclipse on radio wave propagation were done with either a limited number of sites before any theory of the ionosphere had been confirmed or involved collecting data that proved to be unusable because submissions were missing critical information such as date, time or location. This study used the 2017 solar eclipse over the continental U.S. to conduct the first wide-area (across the U.S.) low-frequency (LF) propagation study. The data collection process was crowdsourced through the engagement of students/educators, citizens, ham radio enthusiasts, and the scientific community. In order to accomplish data collection by geographically dispersed citizen scientists, the EclipseMob team designed and shared a low cost, low tool/skill DIY receiver system to collect LF data that leveraged existing cell phone technology and made the experiment more accessible to students and people with no prior experience constructing electronic systems. To support engagement, in addition to web guides (eclipsemob..org), EclipseMob supplied 150 DIY kits and provided build/Q&A webinars and events. For the experiment, participants constructed a simple receiver system consisting of a homemade antenna, a simple homemade receiver to convert the radio frequency (RF) signals to audio frequencies, and a smart phone app. Before, during, and after the eclipse, participants used their receiver systems to record transmitter signal data from WWVB located near Fort Collins, Colorado on 60.000 kHz (a U.S. frequency standard that is operated by NIST and transmits time codes). A second frequency, 55.500 kHz transmitted by a LF station in Dixon, CA was also used. By using the time, date and location features of the smart phone, the problems experienced in earlier experiments could be minimized. By crowdsourcing the observation sites across the U.S., data from a number of different short, medium and long- paths could be obtained as the total eclipse crossed

  7. Accuracy of lunar eclipse observations made by Jesuit astronomers in China.

    NASA Astrophysics Data System (ADS)

    Fatoohi, L. J.; Stephenson, F. R.

    1996-02-01

    The Jesuit astronomers observed numerous lunar eclipses at Beijing and summaries of their observations - made between 1644 and 1785 - are preserved. The various lunar eclipse measurements that the Jesuits made are compared with the results of present-day computation.

  8. The Optical Gravitational Lensing Experiment. Eclipsing Binary Stars in the Large Magellanic Cloud

    NASA Astrophysics Data System (ADS)

    Wyrzykowski, L.; Udalski, A.; Kubiak, M.; Szymanski, M.; Zebrun, K.; Soszynski, I.; Wozniak, P. R.; Pietrzynski, G.; Szewczyk, O.

    2003-03-01

    We present the catalog of 2580 eclipsing binary stars detected in 4.6 square degree area of the central parts of the Large Magellanic Cloud. The photometric data were collected during the second phase of the OGLE microlensing search from 1997 to 2000. The eclipsing objects were selected with the automatic search algorithm based on an artificial neural network. Basic statistics of eclipsing stars are presented. Also, the list of 36 candidates of detached eclipsing binaries for spectroscopic study and for precise LMC distance determination is provided. The full catalog is accessible from the OGLE Internet archive.

  9. Project Report ECLIPSE: European Citizenship Learning Program for Secondary Education

    ERIC Educational Resources Information Center

    Bombardelli, Olga

    2014-01-01

    This paper reports on a European project, the Comenius ECLIPSE project (European Citizenship Learning in a Programme for Secondary Education) developed by six European partners coordinated by the University of Trento in the years 2011-2014. ECLIPSE (co-financed by the EACEA--Education, Audiovisual and Culture Executive Agency) aims at developing,…

  10. The eclipsing AM Herculis variable H1907 + 690

    NASA Technical Reports Server (NTRS)

    Remillard, R. A.; Silber, A.; Stroozas, B. A.; Tapia, S.

    1991-01-01

    The discovery is reported of an eclipsing cataclysmic variable that exhibits up to 10 percent circular polarization at optical wavelengths, securing its classification as an AM Herculis type binary. The object, H1907 + 609, was located with the guidance of X-ray positions from the HEAO 1 survey. Optical CCD photometry exhibits deep eclipses, from which is derived a precise orbital period of 1.743750 hr. The eclipse duration suggests an inclination angle about 80 deg for a main-sequence secondary star. The optical flux has been persistently faint during observations spanning 1987-1990, while the X-ray measurements suggest long-term X-ray variability. The polarization and photometric light curves can be interpreted with a geometric model in which most of the accretion is directed toward a single magnetic pole, with an accretion spot displaced about 17 deg in longitude from the projection of the secondary star on the white dwarf surface.

  11. Eclipse '17 at Indiana University Bloomington

    NASA Astrophysics Data System (ADS)

    Desai, Karna Mahadev; Pilachowski, Catherine A.

    2017-01-01

    August 21, 2017, is the first day of fall classes at Indiana University Bloomington. On campus, we will host viewing stations to assist students, faculty, and community members to watch the eclipse safely. The Kirkwood Observatory solar telescope will provide an online view of the event. Science teachers of Indiana will be surveyed to understand their needs to be prepared for the first week of classes. Working this spring with K12 educators and other local organizations involved in science outreach, we will help to prepare Indiana classrooms to take advantage of the August event to meet the goals of Indiana’s state science standards with eclipse-related activities at all grade levels. These activities are aimed at increasing the scientific literacy in rural Indiana.

  12. First Precision Photometric Observations and Analyses of the Totally Eclipsing, Solar Type Binary V573 Pegasi

    NASA Astrophysics Data System (ADS)

    Samec, R. G.; Caton, D. B.; Faulkner, D. R.

    2018-06-01

    CCD VRcIc light curves of V573 Peg were taken 26 and 27 September and 2, 4, and 6 October, 2017, at the Dark Sky Observatory in North Carolina with the 0.81-m reflector of Appalachian State University. Five times of minimum light were calculated, two primary and three secondary eclipses, from our present observations. The following quadratic ephemeris was determined from all available times of minimum light: JD Hel MinI = 2456876.4958 (2) d + 0.41744860 (8) × E -2.74 (12) × 10^-10 × E2, where the parentheses hold the ± error in the last two digits of the preceding value. A 14-year period study (covered by 24 times of minimum light) reveals a decreasing orbital period with high confidence, possibly due to magnetic braking. The mass ratio is found to be somewhat extreme, M2 / M1 = 0.2629 ± 0.0006 (M1 / M2 = 3.8). Its Roche Lobe fill-out is ˜25%. The solution had no need of spots. The component temperature difference is about 130 K, with the less massive component as the hotter one, so it is a W-type W UMa Binary. The inclination is 80.4 ± 0.1°. Our secondary eclipse shows a time of constant light with an eclipse duration of 24 minutes. More information is given in the following report.

  13. Gravity wave forcing in the middle atmosphere due to reduced ozone heating during a solar eclipse

    NASA Technical Reports Server (NTRS)

    Fritts, David C.; Luo, Zhangai

    1993-01-01

    We present an analysis of the gravity wave structure and the associated forcing of the middle atmosphere induced by the screening of the ozone layer from solar heating during a solar eclipse. Fourier integral techniques and numerical evaluation of the integral solutions were used to assess the wave field structure and to compute the gravity wave forcing of the atmosphere at greater heights. Our solutions reveal dominant periods of a few hours, characteristic horizontal and vertical scales of about 5000 to 10,000 km and 200 km, respectively, and an integrated momentum flux in the direction of eclipse motion of about 5.6 x 10 exp 8 N at each height above the forcing level. These results suggest that responses to solar eclipses may be difficult to detect above background gravity wave and tidal fluctuations until well into the thermosphere. Conversely, the induced body forces may penetrate to considerable heights because of the large wave scales and will have significant effects at levels where the wave field is dissipated.

  14. The ultraviolet spectrum of the eclipsing binary IM Aurigae

    NASA Technical Reports Server (NTRS)

    Bruhweiler, F. C.; Feibelman, W. A.; Kondo, Y.

    1986-01-01

    Low dispersion IUE spectra have been obtained at primary and secondary minima, together with a high dispersion spectrum near maximum, for the eclipsing Algol-type IM Aurigae system. The weak, sharp absorption features noted at two distinct velocities in the high dispersion data are attributed to circumbinary gaseous shells and/or gas streams between the stellar components. The implications of these results for the recently observed increase in O-C values of the primary minimum, which prompted this UV spectral search for evidence of a recent mass-loss event, are discussed.

  15. Interacting Winds in Eclipsing Symbiotic Systems - The Case Study of EG Andromedae

    NASA Astrophysics Data System (ADS)

    Calabrò, Emanuele

    2014-03-01

    We report the mathematical representation of the so called eccentric eclipse model, whose numerical solutions can be used to obtain the physical parameters of a quiescent eclipsing symbiotic system. Indeed the nebular region produced by the collision of the stellar winds should be shifted to the orbital axis because of the orbital motion of the system. This mechanism is not negligible, and it led us to modify the classical concept of an eclipse. The orbital elements obtained from spectroscopy and photometry of the symbiotic EG Andromedae were used to test the eccentric eclipse model. Consistent values for the unknown orbital elements of this symbiotic were obtained. The physical parameters are in agreement with those obtained by means of other simulations for this system.

  16. Social Impact of Solar Eclipse in Indonesia: A Comparative Study

    NASA Astrophysics Data System (ADS)

    Mumpuni, Emanuel S.; Hidayat, Bambang

    2012-09-01

    The social impact and public comprehension of the natural phenomenon varies depending on how a particular cultural background perceives the phenomenon and how the interaction between general public and the authoritative bodies has persisted. While astronomers and scientists have taken for granted that solar eclipse is a natural phenomenon and subjected it to various scientific studies, large percentages of the population have been left uninformed scientifically and have responded to the phenomena quite differently. The technical and scientific aspects of the earliest expedition, to Padang (Sumatra) in 1901, have recently been discussed at length.Two major solar eclipses, namely the 1926 and 1929, offered many scientific outputs as well as results on observations of societies: anthropology, demography, and culinary habits of the local inhabitants. Those days, science was the preserve of a few selected. To a certain degree, many old perceptions of on natural phenomena, with their ruling deities still lingered on. The purpose of this paper is to show the changing views of the endogenous population in particular after the government's massive efforts to enlighten the people and to empower the younger generations in comprehending natural phenomena. The great efforts of the Government of Indonesia's Institute of Sciences (LIPI) related to the June 1983 solar eclipse produced a dramatic change in the sense of appreciation of solar eclipse as a natural phenomenon in consequence of relative motions of the Sun, Moon and the Earth. It took however another five years, till the time of the great eclipse in 1988, to a full fruition in which younger generations as well as older ones abandoned almost completely the old views and embarked on the understanding the value of solar eclipse for science.

  17. A possible additional body in eclipsing binary system HS 2231+2441

    NASA Astrophysics Data System (ADS)

    Vidmachenko, A. P.; Shliakhetska, Ya. O.; Romanyuk, Ya. O.

    2016-12-01

    Analysis of the light curves of eclipsing binary systems HS 2231+2441, obtained with the 36-cm telescope, is made. In processing the photometric data on eclipses by method of timing, obtained evidence for the existence of a third body in the system.

  18. Observation and Analysis of Secondary Eclipses of WASP-32b

    NASA Astrophysics Data System (ADS)

    Garland, Justin; Harrington, Joesph; Cubillos, Patricio; Blecic, Jasmina; Foster, Andrew S.; Bowman, Matthew O.; Maxted, Pierre F. L.

    2014-11-01

    We report two Spitzer secondary eclipses of the exoplanet WASP-32b. Discovered by Maxted et al. (2010), this hot-Jupiter planet has a mass of 3.6 +/- 0.07 Mj, a radius of 1.18 +/- 0.07 Rj, and an orbital period of 2.71865 +/- 0.00008 days around a G-type star. We observed two secondary eclipses in the 3.6 micron and 4.5 micron channels using the Spitzer Space Telescope in 2010 as a part of the Spitzer Exoplanet Target of Opportunity program (program 60003). We present eclipse-depth measurements, estimates of infrared brightness temperatures, and refinements of orbital parameters for WASP-32b from our eclipse measurements as well as amatuer and professional data. Spitzer is operated by the Jet Propulsion Laboratory, California Institute of Technology, under a contract with NASA. This work was supported by NASA Planetary Atmospheres grant NNX12AI69G and NASA Astrophysics Data Analysis Program grant NNX13AF38G. JB holds a NASA Earth and Space Science Fellowship.

  19. MISR Watches Motion of the Moon's Shadow During Total Solar Eclipse

    NASA Image and Video Library

    2017-09-19

    On Aug. 21, 2017, a total solar eclipse swept across the United States -- the first such eclipse in the contiguous 48 states since 1979, and the first cross-country eclipse since 1918. A partial eclipse was visible in all 50 states, and initial estimates suggest that upwards of 20 million people observed the Moon completely obscuring the Sun in the 70-mile-wide (113-kilometer-wide) path of totality. While viewing a total solar eclipse from the ground is an amazing experience, satellites orbiting Earth see the eclipse from a unique perspective. As the Moon's shadow passed through the United States, the Multi-angle Imaging SpectroRadiometer (MISR) instrument aboard NASA's Terra satellite was capturing images of eastern Wyoming and western Nebraska from its altitude of 438 miles (705 kilometers) above the surface. MISR gathers images on a strip about 249 miles (400 kilometers) wide directly below the path of the satellite. Incredibly, given that the shadow of the Moon took only 90 minutes to cross the entire United States, and Terra itself moves at a brisk 16,700 miles per hour from north to south, MISR happened to be in exactly the right place at the right time to capture totality. From the ground, the moment of totality appears suddenly, sweeping over the sky in just a few seconds. "I was unprepared for just how dark it actually was," says Mika Tosca, a researcher who works with MISR data and who observed the eclipse in Nebraska. "The streetlights even turned on. Everything fell silent, and I swear the temperature dropped." From the vantage point of space, however, it’s possible to see the entire shadow of the Moon, with the completely dark, circular umbra and the more diffuse penumbra. MISR contains nine cameras oriented at different angles, viewing forward, downward, and backward along the flight path, resulting in an approximate seven-minute interval for all nine cameras to image a single location on Earth's surface. This animation combines these nine images

  20. Stability of an ophthalmic formulation of polyhexamethylene biguanide in gamma-sterilized and ethylene oxide sterilized low density polyethylene multidose eyedroppers

    PubMed Central

    Wasiak, Mathieu; Jouannet, Mireille; Sautou, Valérie

    2018-01-01

    Background Polyhexamethylene biguanide (PHMB) eye drops are a frequently used medication to treat Acanthamoeba keratitis. In the absence of marketed PHMB eye drops, pharmacy-compounding units are needed to prepare this much needed treatment, but the lack of validated PHMB stability data severely limits their conservation by imposing short expiration dates after preparation. In this study we aim to assess the physicochemical and microbiological stability of a 0.2 mg/mL PHMB eye drop formulation stored in two kinds of polyethylene bottles at two different temperatures. Methods A liquid chromatography coupled with diode array detector stability-indicating method was validated to quantify PHMB, using a cyanopropyl bonded phase (Agilent Zorbax Eclipse XDB-CN column 4.6 × 75 mm with particle size of 3.5 μm) and isocratic elution consisting of acetonitrile/deionized water (3/97 v/v) at a flow rate of 1.3 mL/min. PHMB eye drops stability was assessed for 90 days of storage at 5 and 25 °C in ethylene oxide sterilized low density polyethylene (EOS-LDPE) and gamma sterilized low density polyethylene (GS-LDPE) bottles. The following analyses were performed: visual inspection, PHMB quantification and breakdown products (BPs) screening, osmolality and pH measurements, and sterility assessment. PHMB quantification and BP screening was also performed on the drops emitted from the multidose eyedroppers to simulate in-use condition. Results The analytical method developed meets all the qualitative and quantitative criteria for validation with an acceptable accuracy and good linearity, and is stability indicating. During 90 days of storage, no significant decrease of PHMB concentration was found compared to initial concentration in all stored PHMB eye drops. However, BP were found at day 30 and at day 90 of monitoring in both kind of bottles, stored at 5 and 25 °C, respectively. Although no significant variation of osmolality was found and sterility was maintained during 90 days

  1. The Role of Solar Eclipses in El Nino/La Nina Events

    NASA Astrophysics Data System (ADS)

    Chiu, B. C.

    2005-08-01

    The first hint of the fact that solar eclipses mark the enhanced storms called El Nino or La Nina, came from the article by Robert Allan on analysis of frequencies of these events (2001, perhaps Fourier analysis). One mystery was the cause of a cycle with period 15 to 20 years. But the Saros Series of solar eclipses has a period of 18+ years. Then we had the data from Galapagos Islands for the whole 20th century (Philander 2004). The graph of high and low temperatures indicates El Ninos and La Ninas. A search through charts of solar eclipses for those with good locations for bringing high tides at the Tropics, gave a good picture: those at the eastern coast of the pacific Ocean gave El Ninos, and those at the west gave La Ninas. More than half of the peaks and troughs on the temperature graph can be identified with solar eclipses. We looked more closely at a few events that caused great storms. They are described in J. M. Nash's book, ``El Nino" (2002). The most striking case is that of the 1998 Feb. 22 solar eclipse, which corresponds to the so-called El Nino of 1997-98. In conclusion, I would say that the annual El nino effect is due to the sun's travel between the Tropic of Cancer and Tropic of Capricorn. But the enhanced El Niino/La Nina is due to the coming together of sun and moon in the solar eclipses, which seem to come irregularly.

  2. LX Persei, an eclipsing binary with H and K emission

    NASA Technical Reports Server (NTRS)

    Weiler, E. J.

    1974-01-01

    The masses and MK classes were calculated for the eclipsing spectroscopic binary LX Persei. Its spectrum shows strong H and K emission and doubled lines in the photographic region. The Ca II emission velocity shifts vary in phase with the secondary's absorption lines and are presumably associated with this component. The stars are tentatively classed as G0 V and K0 IV, and the cooler component is the more massive by a ratio of 0.96. The system has a period of 8.0 days.

  3. EFFECTS OF TOTAL SOLAR ECLIPSE ON MENTAL PATIENTS—A CLINICOBIOCHEMICAL CORRELATION

    PubMed Central

    Boral, G. C.; Mishra, D. C.; Pal, S. K.; Ghosh, K. K.

    1981-01-01

    SUMMARY Thirteen treated psychotic cases comprising of eight schizophrenic, four M.D.P. (manic type) and one M. D. P. (depressive type), who were clinically symptom free, were studied in respect of their hormones and behavioural abnormalities under effect of total solar eclipse. Of the hormones studied viz., T2, T4, TSH, Cortisol and prolactin, it is prolactin which showed an increase in titre associated with behavioural abnormalities in concerned patients during and immediately after the total solar eclipse. Deflection in both prolactin and behaviour gradually seemed to normalise over the post eclipse period. PMID:22064835

  4. Initial Results of Interdisciplinary Science Enabled by Eclipse 2017: NASA Perspective

    NASA Astrophysics Data System (ADS)

    Guhathakurta, M.

    2017-12-01

    The exceptionally long path over land of the August 21st total and partial solar eclipse provided an unprecedented opportunity for cross disciplinary studies of the sun, moon, Earth, and their interactions. NASA supported research using ground-based measurements, balloons and planes that "chased" the eclipse as well as data taken from a vast array of orbiting spacecraft, all of which helped scientists take continuous measurements of the sun and the effects of the eclipse on the ionosphere and Earth for relatively long periods of time. This talk will summarize some of the initial findings from these research.

  5. Eclipse project closeup of QF-106 under tow on takeoff on first flight December 20, 1997

    NASA Technical Reports Server (NTRS)

    1997-01-01

    OFF THE GROUND - The Kelly Space & Technology (KST)/USAF/NASA Eclipse project's modified QF-106 lifts off under tow on the project's first tethered flight on December 20, 1997. The successful 18-minute-long flight reached an altitude of 10,000 feet. NASA's Dryden Flight Research Center, Edwards, California, hosted the project, providing engineering and facility support as well as the project pilot. In 1997 and 1998, the Dryden Flight Research Center at Edwards, California, supported and hosted a Kelly Space & Technology, Inc. project called Eclipse, which sought to demonstrate the feasibility of a reusable tow-launch vehicle concept. The project goal was to successfully tow, inflight, a modified QF-106 delta-wing aircraft with an Air Force C-141A transport aircraft. This would demonstrate the possibility of towing and launching an actual launch vehicle from behind a tow plane. Dryden was the responsible test organization and had flight safety responsibility for the Eclipse project. Dryden provided engineering, instrumentation, simulation, modification, maintenance, range support, and research pilots for the test program. The Air Force Flight Test Center (AFFTC), Edwards, California, supplied the C-141A transport aircraft and crew and configured the aircraft as needed for the tests. The AFFTC also provided the concept and detail design and analysis as well as hardware for the tow system and QF-106 modifications. Dryden performed the modifications to convert the QF-106 drone into the piloted EXD-01 (Eclipse eXperimental Demonstrator-01) experimental aircraft. Kelly Space & Technology hoped to use the results gleaned from the tow test in developing a series of low-cost, reusable launch vehicles. These tests demonstrated the validity of towing a delta-wing aircraft having high wing loading, validated the tow simulation model, and demonstrated various operational procedures, such as ground processing of in-flight maneuvers and emergency abort scenarios.

  6. 2017 Total Solar Eclipse

    NASA Image and Video Library

    2017-08-21

    The diamond-ring effect occurred at the beginning and end of totality during a total solar eclipse. As the last bits of sunlight pass through the valleys on the moon's limb, and the faint corona around the sun is just becoming visible, it looks like a ring with glittering diamonds on it. Credit: (NASA/Carla Thomas)

  7. DEBCat: A Catalog of Detached Eclipsing Binary Stars

    NASA Astrophysics Data System (ADS)

    Southworth, J.

    2015-07-01

    Detached eclipsing binary star systems are our primary source of measured physical properties of normal stars. I introduce DEBCat: a catalog of detached eclipsing binaries with mass and radius measurements to the 2% precision necessary to put useful constraints on theoretical models of stellar evolution. The catalog was begun in 2006, as an update of the compilation by Andersen (1991). It now contains over 170 systems, and new results are added on appearance in the refereed literature. DEBCat is available at: http://www.astro.keele.ac.uk/jkt/debcat/.

  8. SPECIAL SEMINAR - The NOTTE experiment, or how to become a Total Solar Eclipse chaser

    ScienceCinema

    None

    2017-12-09

    The NOTTE experiment (Neutrino Oscillations with Telescope during Total Eclipse) aims at searching for visible photons emitted through a possible radiative decay of solar neutrinos. The experiment and the expeditions organized by a group of physicists and astrophysicists from INFN and INAF Bologna hunting for Total Solar Eclipses from 1998 to 2006 wil be described. The results of observations performed during total solar eclipse expeditions in 2001 (Zambia) and 2006 (Sahara desert, Libya) are presented and a beautiful photo gallery will be shown. Other peculiar observations that can be made during a solar eclipse are also illustrated. The seminar will be followed by a brief presentation of future camps for solar eclipse chasers and scientists organized in 2008 in Russia, Kazakhstan, China and Mongolia, in 2009 in Shanghai and on the Easter Island in 2010.

  9. Engage All Americans with Eclipse 2017 Through the Eyes of NASA

    NASA Astrophysics Data System (ADS)

    Ng, C.; Young, C. A.; Mayo, L.; Cline, T. D.; Stephenson, B. E.; Debebe, A.; Lewis, E. M.; Odenwald, S. F.; Hill, S. W.

    2016-12-01

    Join NASA and millions in the U.S. and around the world in observing the August 21, 2017 solar eclipse. This presentation will discuss NASA's education and communication plans for the 2017 eclipse, highlighting some programs, resources, and citizen science activities that will engage and educate many across the country and beyond. NASA will offer unique observations of this celestial event from the ground to space. Additionally, there are do-it-yourself (DIY) science, lunar and math challenges, art contests, Makerspace ideas, and various activities for learners of all ages. Education resources and tool kits may be of particular interest to formal and informal educators. Find out what events are happening in your neighborhood, and plan your own eclipse parties with resources and activities. Last but not the least, experience the eclipse on August 21 and learn more through NASA broadcast programming that will include telescopic views from multiple locations, simple measurements, and live and taped interviews.

  10. Rapid quantification of resveratrol in mouse plasma by ultra high pressure liquid chromatography (UPLC) coupled to tandem mass spectrometry.

    PubMed

    Castillo-Pichardo, Linette; Dharmawardhane, Suranganie; Rodríguez-Orengo, José F

    2014-12-01

    The objective of this study was to develop a rapid and sensitive method for the quantification of resveratrol, a polyphenolic compound with multiple health beneficial effects, in mouse plasma. We used reversed-phase ultra high pressure-liquid chromatography with tandem mass spectrometry detection for the determination of resveratrol levels in mouse plasma. An Agilent Zorbax Eclipse Plus C18 column (2.1 mm x 50 mm, 1.8 μm) was used as the stationary phase. The mobile phase consisted of a gradient formed using 1 mM ammonium fluoride and methanol. Using this improved method, we obtained a retention time of 2.2 min and a total run time of 5 min, for resveratrol. The calibration curve for resveratrol showed a linear range from 0.5 to 100 ng/mL. The average coefficient of variation was 6% for interday variation and 4% for intraday variation. The recovery for resveratrol in mouse plasma was 85 ± 10% (mean ± standard deviation). The method presented herein allows a rapid and very sensitive quantification of resveratrol in mouse plasma at concentrations as low as 500 ppt.

  11. Comparison of pharmacokinetic profiles of moxifloxacin in Caesarean versus non-pregnant sectioned women by fully validated HPLC with fluorescence detection.

    PubMed

    Nemutlu, Emirhan; Kir, Sedef; Eroglu, Hakan; Katlan, Doruk; Ozek, Aykut; Özyüncü, Özgür; Oyüncü, Ozgür; Beksaç, M Sinan

    2010-07-01

    In this study, a simple, rapid, cost-effective, and sensitive reversed-phase high-performance liquid chromatographic method has been developed and validated for the analysis of moxifloxacin in plasma. The chromatographic separation was achieved on a Zorbax Eclipse XDB-C18 column (150 mm x 4.6 mm i.d.) connected to a Phenomenex C(18) column (4 mm x 3.0 mm i.d.) using a mixture of acetonitrile: 15 mM citrate buffer (pH 3) (23:77, v/v) as the mobile phase with isocratic system at a flow rate of 1 mL/min. Fluorescence detection was employed with excitation at 290 nm and emission at 500 nm. Lomefloxacin was used as internal standard. Plasma samples were prepared with addition of acetonitrile only. The method was fully validated according to the International Conference on Harmonization (ICH) guidelines. The results of the validation parameters were: linearity range, 3-6000 ng/mL (R(2) = 0.9994); mean recovery, 100.48 %; limit of quantification, 5 ng/mL; limit of detection, 1 ng/mL; and intra- and inter-day precision less than 3.2% and 5.1%, respectively. The robustness of the method was evaluated and confirmed with fractional factorial design. After validation studies, the method was applied in order to conclude the effects of pregnancy on postoperative pharmacokinetic profiles of moxifloxacin. For this aim, moxifloxacin was given to non-pregnant women (n=9) and caesarean-sectioned women (n=6) as a single intravenous dose (400 mg Avelox(R) infusion). Plasma samples were analyzed in order to compare pharmacokinetic profiles of pregnants and non-pregnants. Peak serum concentrations of non-pregnant and caesarean-sectioned women at the arterial port after the infusion were 4.95 +/- 1.50 and 1.56 +/- 0.16 microg/mL, respectively. The mean elimination half-life, volume of distribution and calculated area under the concentration-time curve (AUC)(0-infinity) were 5.54 +/- 0.73 h, 65.58 +/- 6.30 L and 49.95 +/- 6.30 microg.h/mL for non-pregnant women and 3.50 +/- 0.37 h, 215

  12. The detached eclipsing binary TX Her revisited

    NASA Astrophysics Data System (ADS)

    Erdem, A.; Aliçavuş, F.; Soydugan, F.; Doğru, S. S.; Soydugan, E.; Çiçek, C.; Demircan, O.

    2011-12-01

    This paper presents new CCD Bessell BVRI light curves and photometric analysis of the Algol-type binary star TX Her. The CCD observations were carried out at Çanakkale Onsekiz Mart University Observatory in 2010. New BVRI light curves from this study and radial velocity curves from Popper (1970) were solved simultaneously using modern light and radial velocity curves synthesis methods. The general results show that TX Her is a well-detached eclipsing binary, however, both component stars fill at least half of their Roche lobes. A significant third light contribution to the total light of the system could not be determined. Using O- C residuals formed by the updated minima times, an orbital period study of the system was performed. It was confirmed that the tilted sinusoidal O- C variation corresponds to an apparent period variation caused by the light travel time effect due to an unseen third body. The following absolute parameters of the components were derived: M1 = 1.62 ± 0.04 M ⊙, M2 = 1.45 ± 0.03 M ⊙, R1 = 1.69 ± 0.03 R ⊙, R2 = 1.43 ± 0.03 R ⊙, L1 = 8.21 ± 0.90 L ⊙ and L2 = 3.64 ± 0.60 L ⊙. The distance to TX Her was calculated as 155 ± 10 pc, taking into account interstellar extinction. The position of the components of TX Her in the HR diagram are also discussed. The components are young stars with an age of ˜500 Myr.

  13. EC 10246-2707: an eclipsing subdwarf B + M dwarf binary

    NASA Astrophysics Data System (ADS)

    Barlow, B. N.; Kilkenny, D.; Drechsel, H.; Dunlap, B. H.; O'Donoghue, D.; Geier, S.; O'Steen, R. G.; Clemens, J. C.; LaCluyze, A. P.; Reichart, D. E.; Haislip, J. B.; Nysewander, M. C.; Ivarsen, K. M.

    2013-03-01

    We announce the discovery of a new eclipsing hot subdwarf B + M dwarf binary, EC 10246-2707, and present multicolour photometric and spectroscopic observations of this system. Similar to other HW Vir-type binaries, the light curve shows both primary and secondary eclipses, along with a strong reflection effect from the M dwarf; no intrinsic light contribution is detected from the cool companion. The orbital period is 0.118 507 9936 ± 0.000 000 0009 d, or about 3 h. Analysis of our time series spectroscopy reveals a velocity semi-amplitude of K1 = 71.6 ± 1.7 km s-1 for the sdB and best-fitting atmospheric parameters of Teff = 28 900 ± 500 K, log g = 5.64 ± 0.06 and log N(He)/N(H) = -2.5 ± 0.2. Although we cannot claim a unique solution from modelling the light curve, the best-fitting model has an sdB mass of 0.45 M⊙ and a cool companion mass of 0.12 M⊙. These results are roughly consistent with a canonical-mass sdB and M dwarf separated by a ˜ 0.84 R⊙. We find no evidence of pulsations in the light curve and limit the amplitude of rapid photometric oscillations to <0.08 per cent. Using 15 yr of eclipse timings, we construct an observed minus calculated (O - C) diagram but find no statistically significant period changes; we rule out |dot{P}| > 7.2 × 10^{-12}. If EC 10246-2707 evolves into a cataclysmic variable, its period should fall below the famous cataclysmic variable period gap.

  14. Implementation of Bessel's method for solar eclipses prediction in the WRF-ARW model

    NASA Astrophysics Data System (ADS)

    Montornes, Alex; Codina, Bernat; Zack, John W.; Sola, Yolanda

    2016-05-01

    Solar eclipses are predictable astronomical events that abruptly reduce the incoming solar radiation into the Earth's atmosphere, which frequently results in non-negligible changes in meteorological fields. The meteorological impacts of these events have been analyzed in many studies since the late 1960s. The recent growth in the solar energy industry has greatly increased the interest in providing more detail in the modeling of solar radiation variations in numerical weather prediction (NWP) models for the use in solar resource assessment and forecasting applications. The significant impact of the recent partial and total solar eclipses that occurred in the USA (23 October 2014) and Europe (20 March 2015) on solar power generation have provided additional motivation and interest for including these astronomical events in the current solar parameterizations.Although some studies added solar eclipse episodes within NWP codes in the 1990s and 2000s, they used eclipse parameterizations designed for a particular case study. In contrast to these earlier implementations, this paper documents a new package for the Weather Research and Forecasting-Advanced Research WRF (WRF-ARW) model that can simulate any partial, total or hybrid solar eclipse for the period 1950 to 2050 and is also extensible to a longer period. The algorithm analytically computes the trajectory of the Moon's shadow and the degree of obscuration of the solar disk at each grid point of the domain based on Bessel's method and the Five Millennium Catalog of Solar Eclipses provided by NASA, with a negligible computational time. Then, the incoming radiation is modified accordingly at each grid point of the domain.This contribution is divided in three parts. First, the implementation of Bessel's method is validated for solar eclipses in the period 1950-2050, by comparing the shadow trajectory with values provided by NASA. Latitude and longitude are determined with a bias lower than 5 x 10-3 degrees (i

  15. The climate of HD 189733b from fourteen transits and eclipses measured by Spitzer

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

    Agol, E.; /Washington U., Seattle, Astron. Dept. /Santa Barbara, KITP /UC, Santa Barbara; Cowan, Nicolas B.

    We present observations of six transits and six eclipses of the transiting planet system HD 189733 taken with the Spitzer Space Telescope IRAC camera at 8 microns, as well as a re-analysis of previously published data. We use several novel techniques in our data analysis, the most important of which is a new correction for the detector 'ramp' variation with a double-exponential function which performs better and is a better physical model for this detector variation. Our main scientific findings are: (1) an upper limit on the variability of the day-side planet flux of 2.7% (68% confidence); (2) the mostmore » precise set of transit times measured for a transiting planet, with an average accuracy of 3 seconds; (3) a lack of transit-timing variations, excluding the presence of second planets in this system above 20% of the mass of Mars in low-order mean-motion resonance at 95% confidence; (4) a confirmation of the planet's phase variation, finding the night side is 64% as bright as the day side, as well as an upper limit on the night-side variability of 17% (68% confidence); (5) a better correction for stellar variability at 8 micron causing the phase function to peak 3.5 hours before secondary eclipse, confirming that the advection and radiation timescales are comparable at the 8 micron photosphere; (6) variation in the depth of transit, which possibly implies variations in the surface brightness of the portion of the star occulted by the planet, posing a fundamental limit on non-simultaneous multi-wavelength transit absorption measurements of planet atmospheres; (7) a measurement of the infrared limb-darkening of the star, which is in good agreement with stellar atmosphere models; (8) an offset in the times of secondary eclipse of 69 seconds, which is mostly accounted for by a 31 second light travel time delay and 33 second delay due to the shift of ingress and egress by the planet hot spot; this confirms that the phase variation is due to an offset hot spot on

  16. Impact Results From the Astronomers Without Borders Building on the Eclipse Education Program

    NASA Astrophysics Data System (ADS)

    Bartolone, L. M.; Simmons, M.; Nelson, A.; Kruse, B.

    2017-12-01

    Astronomers Without Borders "Building on the Eclipse Education Program" was its first to move beyond outreach, exploring how to impact science identity, attitudes towards STEM and inspire audiences to explore careers in STEM. Inspired by the eclipse, educators and scientists were brought together in an online community to support one another in learning about the Sun and light after audiences were inspired by the Total Solar Eclipse. The program also collected and analyzed data on participating groups in an attempt to have more information about audiences for the next total solar eclipse to cross the United States in 2024. Although we anticipate the program will be ongoing, preliminary results will be presented.

  17. [Determination of six plant growth regulator residues in strawberry by liquid chromatography-quadrupole time of flight mass spectrometry].

    PubMed

    Liu, Jingjing; Gong, Ping; Zhang, Xiaomei; Wang, Jianhua; Wang, Jingtang

    2012-10-01

    A novel method was established for the determination of six plant growth regulators (PGRs), 2,4-dichlorophenoxy acetic (2,4-D), 4-chlorophenoxy-acetic acid (CAP), 4-(3-indolyl)-butyric acid (BAA), forchlorfenuron (CPPU), abscisic acid (ABA) and trans-zeatin (ZT) in strawberry using liquid chromatography-quadrupole-time of flight mass spectrometry (LC-Q TOF MS). The Quick, Easy, Cheap, Effective, Rugged and Safe method (QuEChERS) has been validated for the extraction. In this QuEChERS method, the sample was extracted by acetonitrile and cleaned up with C18 adsorbent. The extract was measured directly by LC-Q TOF MS with electrospray ionization in negative mode. The compounds were separated on an Eclipse XDB-C8 column (150 mm x 4.6 mm, 5 microm) with acetonitrile-5 mmol/L ammonium acetate-0. 1% formic acid as mobile phase under gradient elution. The confirmatory analysis was carried out by determining the accurate masses of all compounds and fragment ions upon Target MS/MS. The limits of detection (LODs) were between 1 microg/kg and 5 microg/kg. The linear range was 0.005-1.0 mg/L for each analyte. The recoveries ranged from 87% to 107% with the relative standard deviations (RSDs) less than 10% (n = 6). The method was proved to be simple and accurate.

  18. On the detection and attribution of gravity waves generated by the 20 March 2015 solar eclipse.

    PubMed

    Marlton, G J; Williams, P D; Nicoll, K A

    2016-09-28

    Internal gravity waves are generated as adjustment radiation whenever a sudden change in forcing causes the atmosphere to depart from its large-scale balanced state. Such a forcing anomaly occurs during a solar eclipse, when the Moon's shadow cools part of the Earth's surface. The resulting atmospheric gravity waves are associated with pressure and temperature perturbations, which in principle are detectable both at the surface and aloft. In this study, surface pressure and temperature data from two UK sites at Reading and Lerwick are examined for eclipse-driven gravity wave perturbations during the 20 March 2015 solar eclipse over northwest Europe. Radiosonde wind data from the same two sites are also analysed using a moving parcel analysis method, to determine the periodicities of the waves aloft. On this occasion, the perturbations both at the surface and aloft are found not to be confidently attributable to eclipse-driven gravity waves. We conclude that the complex synoptic weather conditions over the UK at the time of this particular eclipse helped to mask any eclipse-driven gravity waves.This article is part of the themed issue 'Atmospheric effects of solar eclipses stimulated by the 2015 UK eclipse'. © 2016 The Authors.

  19. The remarkable eclipsing asynchronous AM Herculis binary RX J19402-1025

    NASA Technical Reports Server (NTRS)

    Patterson, Joseph; Skillman, David R.; Thorstensen, John; Hellier, Coel

    1995-01-01

    We report on two years of photometric and spectroscopic observation of the recently discovered AM Herculis star RX J19402-1025. A sharp eclipse feature is present in the optical and X-ray light curves, repeating with a period of 12116.290 +/- 0.003 s. The out-of-eclipse optical waveform contains approximately equal contributions from a signal at the same period and another signal at 12150 s. As these signals drift in and out of phase, the wave form of the light curve changes in a complex but predictable manner. After one entire 'supercycle' of 50 days (the beat period between the shorter periods), the light curve returns to its initial shape. We present long-term ephemerides for each of these periods. It is highly probable that the eclipse period is the underlying orbital period, while the magnetic white dwarf rotates with P = 12150 s. The eclipses appear to be eclipses of the white dwarf by the secondary star. But there is probably also a small obscuring effect from cold gas surrounding the secondary, especially on the orbit-leading side where the stream begins to fall towards the white dwarf. The latter hypothesis can account for several puzzling effects in this star, as well as the tendency among most AM Her stars for the sharp emission-line components to slightly precede the actual motion of the secondary. The presence of eclipses in an asynchronous AM Her star provides a marvelous opportunity to study how changes in the orientation of magnetic field lines affect the accretion flows. Repeated polarimetric light curves and high-resolution studies of the emission lines are now critical to exploit this potential.

  20. Acoustic Gravity Waves in the Ionosphere and Thermosphere During the 2017 Solar Eclipse

    NASA Astrophysics Data System (ADS)

    Lin, C. Y. T.; Deng, Y.

    2017-12-01

    During the 2017 solar eclipse, as the sudden cavity of solar radiation created by the lunar shadow moves across the United States on August 21, 2017, decreases in local IT temperature and density are expected. The average velocity of the total solar eclipse across the United States is 700 m/s. The forefront and wake of the lunar shadow are expected to induce acoustic gravity waves according to previous studies of atmosphere waves induced by traveling wave packets moving at different velocities. Meanwhile, moving toward the cross-track direction of the obscuration footprint, weaker transitions will likely create mesoscale to large-scale traveling disturbances. We will use the Global Ionosphere Thermosphere Model, a global circulation model solving for non-hydrostatic equations, with high-resolution settings to investigate the IT responses related to the acoustic-gravity wave perturbations during the 2017 solar eclipse. The simulation will be performed with a sub-degree resolution in longitude and latitude for 3 hours when the atmosphere of the North America sector is mostly obscured. The observable differences between the eclipsed and non-eclipsed scenarios will be examined in detail and be interpreted as consequences from the solar eclipse. We will investigate the evolution of waves during the event and establish a theoretical baseline for further comparisons with observations.

  1. The Eclipsing Binary On-Line Atlas (EBOLA)

    NASA Astrophysics Data System (ADS)

    Bradstreet, D. H.; Steelman, D. P.; Sanders, S. J.; Hargis, J. R.

    2004-05-01

    In conjunction with the upcoming release of \\it Binary Maker 3.0, an extensive on-line database of eclipsing binaries is being made available. The purposes of the atlas are: \\begin {enumerate} Allow quick and easy access to information on published eclipsing binaries. Amass a consistent database of light and radial velocity curve solutions to aid in solving new systems. Provide invaluable querying capabilities on all of the parameters of the systems so that informative research can be quickly accomplished on a multitude of published results. Aid observers in establishing new observing programs based upon stars needing new light and/or radial velocity curves. Encourage workers to submit their published results so that others may have easy access to their work. Provide a vast but easily accessible storehouse of information on eclipsing binaries to accelerate the process of understanding analysis techniques and current work in the field. \\end {enumerate} The database will eventually consist of all published eclipsing binaries with light curve solutions. The following information and data will be supplied whenever available for each binary: original light curves in all bandpasses, original radial velocity observations, light curve parameters, RA and Dec, V-magnitudes, spectral types, color indices, periods, binary type, 3D representation of the system near quadrature, plots of the original light curves and synthetic models, plots of the radial velocity observations with theoretical models, and \\it Binary Maker 3.0 data files (parameter, light curve, radial velocity). The pertinent references for each star are also given with hyperlinks directly to the papers via the NASA Abstract website for downloading, if available. In addition the Atlas has extensive searching options so that workers can specifically search for binaries with specific characteristics. The website has more than 150 systems already uploaded. The URL for the site is http://ebola.eastern.edu/.

  2. Distance Estimation for Eclipsing X-Ray Pulsars

    NASA Astrophysics Data System (ADS)

    Wilson, Robert E.; Paul, B.; Raichur, H.

    2006-06-01

    Recent interest in eclipsing binaries as distance indicators leads naturally into direct distance estimation for X-ray pulsars by combination of pulse arrival times, radial velocities, X-ray eclipse duration, and spectra. Optical light curves may help in some cases by measuring tides and irradiation, although dynamical tides in eccentric systems limit light curve usefulness. Pulse arrivals give an absolute scale and also orbit shape and orientation, which may be poorly known from radial velocities. For example, orbital eccentricity of 0.09 is known from Vela X1 pulse arrivals, although optical velocities are too noisy to measure eccentricity accurately. Combined pulse and optical velocity data give mass information. A lower limit to sin i from eclipse duration sets a lower limit to R2, and for the general eccentric case. A mass ratio sets lobe size and thus an upper limit to R2, so boxing R2 within a narrow range may be possible. T2 can be assessed from spectra so EB distance estimation can work if magnitude is known in one or more standard bands such as B or V. Realistic distance uncertainties are explored. In regard to new observations, Vela X-1 was observed by RXTE over about nine days in January 2005, including an eclipse of about 3.5 days. We extracted the light curves with time resolution 0.125 s. Spin period measurements by the Chi square criterion show Doppler variation with orbital phase and mean spin period 283.5 s. Pulse profiles of that period were averaged in sets of 10 at 138 phases. Cross correlation for the first 40 pulses show the expected Doppler arrival time variation. As the Vela X-1 pulse period is large compared to light travel time across the orbit, the pulses are already phase connected. Support is by U.S. National Science Foundation grant 0307561.

  3. Infrared spectroscopy of the transiting extrasolar planet HD 209458 b during secondary eclipse

    NASA Astrophysics Data System (ADS)

    Richardson, Lee Jeremy

    2003-10-01

    We present spectroscopic observations that place strong limits on the atmospheric structure of the transiting extrasolar planet HD 209458 b. The discovery of the transit has led to several new observations that have provided the most de tailed information on the physical properties of a planet outside the solar system. These observations have concentrated on the primary eclipse, the time at which the planet crosses in front of the star as seen from Earth. The measurements have determined the basic physical characteristics of the planet, including radius, mass, average density, and orbital inclination, and have even refined values of the stellar mass and radius. Transmission spectroscopy of the system during primary eclipse resulted in the first detection of the atmosphere of an extrasolar planet, with the measurement of the sodium doublet. The present work discusses the first reported attempts to detect the secondary eclipse, or the disappearance of the planet behind the star, in the infrared. We devise the method of ‘occultation spectroscopy’ to detect the planetary spectrum, by searching in combined light for subtle changes in the shape of the spectrum as the planet passes behind the star. Predicted secondary eclipse events were observed from the Very Large Telescope (VLT) on UT 8 and 15 July 2001 using the Infrared Spectrometer and Array Camera (3.5 3.7 μm). Further observations from the NASA Infrared Telescope Facility (IRTF) using the SpeX instrument (1.9 4.2 μm) included two predicted secondary eclipse events on UT 20 and 27 September 2001. Analysis of these data reveal a statistically significant non- detection of the planetary spectrum. The results place strong limits on the structure of the planetary atmosphere and reject widely-accepted models for the planet that assume the incident stellar radiation is completely absorbed and re-emitted in the substellar hemisphere. Situations that remain consistent with our data include an isothermal atmosphere or

  4. Analysis of Geomagnetic Field Variations during Total Solar Eclipses Using INTERMAGNET Data

    NASA Astrophysics Data System (ADS)

    KIM, J. H.; Chang, H. Y.

    2017-12-01

    We investigate variations of the geomagnetic field observed by INTERMAGNET geomagnetic observatories over which the totality path passed during a solar eclipse. We compare results acquired by 6 geomagnetic observatories during the 4 total solar eclipses (11 August 1999, 1 August 2008, 11 July 2010, and 20 March 2015) in terms of geomagnetic and solar ecliptic parameters. These total solar eclipses are the only total solar eclipse during which the umbra of the moon swept an INTERMAGNET geomagnetic observatory and simultaneously variations of the geomagnetic field are recorded. We have confirmed previous studies that increase BY and decreases of BX, BZ and F are conspicuous. Interestingly, we have noted that variations of geomagnetic field components observed during the total solar eclipse at Isla de Pascua Mataveri (Easter Island) in Chile (IPM) in the southern hemisphere show distinct decrease of BY and increases of BX and BZ on the contrary. We have found, however, that variations of BX, BY, BZ and F observed at Hornsund in Norway (HRN) seem to be dominated by other geomagnetic occurrence. In addition, we have attempted to obtain any signatures of influence on the temporal behavior of the variation in the geomagnetic field signal during the solar eclipse by employing the wavelet analysis technique. Finally, we conclude by pointing out that despite apparent success a more sophisticate and reliable algorithm is required before implementing to make quantitative comparisons.

  5. An outstanding researcher of the solar eclipses- Nicolas Donitch

    NASA Astrophysics Data System (ADS)

    Gaina, Alex

    1998-09-01

    Nicolae Donitch (1874, Chisinau-1958, Nice, France?) worked in Russia (until 1917), Romania (1918-1944) and France (1945-1958?). His observatory was placed in Dubossary-Vechi (where he worked with some intervals between 1908 and 1944. He was designated by the Russian Academy of Sciences for the observations of the total Solar eclipse in Elche (Spain) on 28 May 1900. Other solar eclipses observed by N. Donitch: 17-18 may 1901, Padong (Sumatra); 1904 - the annular eclipse of the Sun in Pnom-Penh (Cambodge); august 1905, Alcala de Chisvert (Spain) and Assuan (Upper Egypt); 16/17 April 1912, Portugal; 21 august 1914, Crimea; 1925, USA; 1929 Indochina and Philipines; 1930, Egypt; 1932 Egypt and cape Porpoise,Maine USA; 1936, Inneboli, Turkey. Other solar investigations by N. Donitch; Solar cromosphere (Odessa, 1902; Mount- Blanch, 1902-1903); The passage of the planet Mercury through the solar disk (November, 1907, Egypt; October 1914, Algeria).

  6. The Astrophysics of the Solar Corona at the August 21, 2017, American Total Solar Eclipse

    NASA Astrophysics Data System (ADS)

    Pasachoff, Jay

    2017-01-01

    The first total solar eclipse to cross the United States from coast to coast in 99 years will occur on August 21, 2017, with a 70-mile-wide path of totality from Oregon to South Carolina, with cloudiness statistics more favorable in the northwest than in the southeast. I will discuss a series of observations of the solar corona made during recent solar eclipses and related spacecraft observations. I will further discuss plans for using the 2017 eclipse for furthering our studies of the heating of the solar corona to millions of kelvins, of the dynamics of coronal mass ejections and polar plumes, and of the response of the corona to the solar magnetic field. I will conclude by discussing public-education plans for the eclipse, during which the whole U.S., Mexico, Central America, and Canada will enjoy a partial eclipse. My work at solar eclipses has recently been supported by the NSF and the Committee for Research and Exploration of the National Geographic Society, and I thank them both for research grants for our scientific studies of the 2017 total eclipse, including AGS-1602461 from the NSF and 987816 from National Geographic.

  7. 2017 Solar Eclipse Event

    NASA Image and Video Library

    2017-06-11

    Brad Addona views the beginning of the August 21, 2017 at a viewing event for Marshall Space Flight Center’s activities building for Marshall employees. The Huntsville area experienced 97 percent occultation, nearly a complete blocking out of the sun by the orbit of Earth's moon. The next opportunity to view a solar eclipse in the eastern and central United States will occur in April 2024.

  8. Eclipses across the Curriculum

    ERIC Educational Resources Information Center

    Fulco, Charles

    2017-01-01

    On Monday, August 21, 2017 there will be a Total Solar Eclipse. This will be the first time the Moon's umbra has touched the continental United States since 1979 and the first totality to span the country coast-to-coast since 1918. From within parts of Oregon and through 14 states to South Carolina, the Moon will completely hide the Sun for a few…

  9. SPECIAL SEMINAR - The NOTTE experiment, or how to become a Total Solar Eclipse chaser

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

    None

    2011-02-08

    The NOTTE experiment (Neutrino Oscillations with Telescope during Total Eclipse) aims at searching for visible photons emitted through a possible radiative decay of solar neutrinos. The experiment and the expeditions organized by a group of physicists and astrophysicists from INFN and INAF Bologna hunting for Total Solar Eclipses from 1998 to 2006 wil be described. The results of observations performed during total solar eclipse expeditions in 2001 (Zambia) and 2006 (Sahara desert, Libya) are presented and a beautiful photo gallery will be shown. Other peculiar observations that can be made during a solar eclipse are also illustrated. The seminar willmore » be followed by a brief presentation of future camps for solar eclipse chasers and scientists organized in 2008 in Russia, Kazakhstan, China and Mongolia, in 2009 in Shanghai and on the Easter Island in 2010.« less

  10. Green and simple analytical method to determine benzimidazoles in milk samples by using salting-out assisted liquid-liquid extraction and capillary liquid chromatography.

    PubMed

    Tejada-Casado, Carmen; Del Olmo-Iruela, Monsalud; García-Campaña, Ana M; Lara, Francisco J

    2018-08-01

    A green and simple multiresidue method using capillary liquid chromatography (CLC) with UV-diode array detection (DAD) has been developed for the determination of sixteen benzimidazoles (BZs) and its metabolites in milk samples. The separation was achieved in <32 min, using a Zorbax XDB-C18 column (150 mm × 0.5 mm I.D, 5 μm), with a mobile phase consisting of 50 mM ammonium acetate (solvent A) and a mixture of acetonitrile/methanol (1:1 v/v) (solvent B), at a flow rate of 9 μL min -1 . The temperature of the column was 20 °C and 6 μL of sample were injected. In spite of the complexity of milk samples, an effective, simple and fast sample preparation method called salting out-assisted liquid-liquid extraction (SALLE) was developed for the analysis of these compounds in cow milk samples. To obtain satisfactory extraction efficiencies for the studied analytes, several parameters affecting the SALLE procedure were optimized including the amount of sample, type and volume of the extraction solvent, and the nature and amount of the salt. Good linearity was obtained (R 2  > 0.9985 for all BZs) with limits of detection (LOD) between 1.0 and 2.8 μg kg -1 . Relative standard deviations of repeatability and intermediate precision were below 1.6 and 14.2%, respectively. Satisfactory recoveries between 79.1 and 99.6% were also obtained for three types of milk samples (cow, sheep and goat). The advantages of a miniaturized technique such as CLC in terms of better efficiencies and reduced solvent consumption, combined with the simplicity of the SALLE procedure, make this method a useful alternative for the monitoring of these residues at trace level. Copyright © 2018 Elsevier B.V. All rights reserved.

  11. Total Solar Eclipse: “Through The Eyes of NASA,” Part 4

    NASA Image and Video Library

    2017-08-21

    During the eclipse, 14 states across the U.S. were in the path of totality and experienced more than two minutes of darkness in the middle of the day – with a partial eclipse viewable all across North America. The broadcast – Eclipse Across America: Through the Eyes of NASA – covered locations along the path of totality, from Oregon to South Carolina including public reactions from all ages. The eclipse’s long path over land provided a unique opportunity to study the Sun, Earth, Moon and their interaction.

  12. Total Solar Eclipse: “Through The Eyes of NASA,” Part 3

    NASA Image and Video Library

    2017-08-21

    During the eclipse, 14 states across the U.S. were in the path of totality and experienced more than two minutes of darkness in the middle of the day – with a partial eclipse viewable all across North America. The broadcast – Eclipse Across America: Through the Eyes of NASA – covered locations along the path of totality, from Oregon to South Carolina including public reactions from all ages. The eclipse’s long path over land provided a unique opportunity to study the Sun, Earth, Moon and their interaction.

  13. Lightcurve Analysis for Two Near-Earth Asteroids Eclipsed by the Earth's Shadow

    NASA Astrophysics Data System (ADS)

    Birtwhistle, Peter

    2018-07-01

    Photometry was obtained from Great Shefford Observatory of near-Earth asteroids 2012 XE54 in 2012 and 2016 VA in 2016 during close approaches. A superfast rotation period has been determined for 2012 XE54 and H-G magnitude system coefficients have been estimated for 2016 VA. While under observation, 2012 XE54 underwent a deep penumbral eclipse by the Earth's shadow and 2016 VA also experienced a total eclipse by the Earth's shadow. The dimming due to the eclipses is modeled taking into account solar limb darkening.

  14. Meteorological responses in the atmospheric boundary layer over southern England to the deep partial eclipse of 20 March 2015

    PubMed Central

    2016-01-01

    A wide range of surface and near-surface meteorological observations were made at the University of Reading’s Atmospheric Observatory in central southern England (latitude 51.441° N, longitude 0.938° W, altitude 66 m above mean sea level) during the deep partial eclipse on the morning of 20 March 2015. Observations of temperature, humidity, radiation, wind speed and direction, and atmospheric pressure were made by computerized logging equipment at 1 Hz, supplemented by an automated cloud base recorder sampling at 1 min intervals and a high-resolution (approx. 10 m vertical interval) atmospheric sounding by radiosonde launched from the same location during the eclipse. Sources and details of each instrumental measurement are described briefly, followed by a summary of observed and derived measurements by meteorological parameter. Atmospheric boundary layer responses to the solar eclipse were muted owing to the heavily overcast conditions which prevailed at the observing location, but instrumental records of the event documented a large (approx. 80%) reduction in global solar radiation, a fall in air temperature of around 0.6°C, a decrease in cloud base height, and a slight increase in atmospheric stability during the eclipse. Changes in surface atmospheric moisture content and barometric pressure were largely insignificant during the event. This article is part of the themed issue ‘Atmospheric effects of solar eclipses stimulated by the 2015 UK eclipse’. PMID:27550762

  15. Confirming Variability in the Secondary Eclipse Depth of the Rocky Super-Earth 55 Cancri e

    NASA Astrophysics Data System (ADS)

    Tamburo, Patrick; Mandell, Avi; Deming, Drake; Garhart, Emily

    2017-01-01

    We present a reanalysis of Spitzer transit and secondary eclipse observations of the rocky super Earth 55 Cancri e using Pixel Level Decorrelation (Deming et al. 2015). Secondary eclipses of this planet were found to be significantly variable by Demory et al. (2016), implying a changing brightness temperature which could be evidence of volcanic activity due to tidal forces. If genuine, this result would represent the first evidence for such a process outside of bodies in our own solar system, and would further expand our understanding of the huge variety of planetary systems that can develop in our universe. Spitzer eclipse observations, however, are subject to strong systematic effects which can heavily impact the retrieved eclipse model. A reanalysis of this result with an independent method is therefore needed to confirm eclipse depth variability. We tentatively confirm variability, finding a shallower increase in eclipse depth over the course of observations compared to Demory et al. (2015).

  16. The 1st of April 2470 BC Total Solar Eclipse Seen by the Prophet Ibraheem

    NASA Astrophysics Data System (ADS)

    Yousef, S. M.

    The Holy Quran describes a phenomenon seen by young Abraham that can only fit a solar eclipse. Two criteria were given for this particular eclipse; first only one planet was seen as soon as it got dark and second no corona was seen. In order to justify the first selection rule, examinations of solar and planetary longitudes for total solar eclipses passing over Babel were carried out. Only the eclipse of the 1st of April 2470 BC meets this condition, as it was only Venus that was seen at that eclipse. The second selection rule was also naturally fulfilled, as Babel happened to be on the border of the totality zone hence no corona was seen, however all the time the moon glistened as Baily's beads. There is no doubt that the prophet Abraham witnessed the 1st of April total solar eclipse that passed over Babel. This will put him about 470 years backward than it was previously anticipated.

  17. NSV 1907 - A new eclipsing, nova-like cataclysmic variable

    NASA Astrophysics Data System (ADS)

    Hümmerich, Stefan; Gröbel, Rainer; Hambsch, Franz-Josef; Dubois, Franky; Ashley, Richard; Gänsicke, Boris T.; Vanaverbeke, Siegfried; Bernhard, Klaus; Wils, Patrick

    2017-01-01

    NSV 1907, formerly listed as an irregular variable in variability catalogues, was classified as an Algol-type eclipsing binary in the Catalina Surveys Periodic Variable Star Catalogue. We have identified NSV 1907 as an ultraviolet (UV) bright source using measurements from the GALEX space telescope and detected obvious out-of-eclipse variability in archival photometric data from the Catalina Sky Survey, which instigated a closer examination of the object. A spectrum and extensive multicolour photometric observations were acquired, from which we deduce that NSV 1907 is a deeply eclipsing, nova-like cataclysmic variable. Apart from the orbital variations (deep eclipses with a period of P ≈ 6.63 hours), changes in mean brightness and irregular short-term variability (flickering) were observed. The presence of a secondary minimum at phase φ ≈ 0.5 was established, which indicates a significant contribution of the companion star to the optical flux of the system. We find possible evidence for sinusoidal variations with a period of P ≈ 4.2 d, which we interpret as the nodal precession period of the accretion disc. No outbursts or VY Scl-like drops in brightness were detected either by the CSS or during our photometric monitoring. Because of its spectral characteristics and the observed variability pattern, we propose NSV 1907 as a new moderately bright long-period SW Sextantis star. Further photometric and spectroscopic observations are encouraged.

  18. Worldwide photometry of the January 1989 Tau Persei eclipse

    NASA Technical Reports Server (NTRS)

    Hall, Douglas S.; Curott, David R.; Barksdale, William S.; Diethelm-Sutter, Roger; Ells, Jack

    1991-01-01

    New UBV photoelectric photometry of Tau Persei obtained at 19 different observatories during its recent January 1989 eclipse is presented. Mideclipse occurred at JD 2 447 542.31 + or - 0.01. The resulting light curve, though not complete at all phases, is solved for the elements with the help of two quantities derived from spectroscopy: the eclipse is 84 percent total at mideclipse, and the ratio of the radii is 0.135 + or - 0.01. Radii relative to the semimajor axis are 0.0236 for the G5 giant and 0.0032 for the A2 star. With a reasonable total mass assumed, the absolute radii say the A2 star could be luminosity class V or somewhat evolved and the G5 star is between III and II but could be closer to II. The G5 giant is brighter than the A2 star by 1.72 mag in V and the color excess in B - V is 0.06 mag, both quantities consistent (within uncertainties) with earlier estimates of Ake (1986). The eclipse duration, from first to fourth contact, is 2.09 day. The orbital inclination is 88.74 deg, consistent with what McAlister derived from speckle interferometry. Because of the large (e = 0.73) eccentricity, there is no secondary eclipse at all.

  19. Spirit View of Phobos Eclipse, Sol 675

    NASA Technical Reports Server (NTRS)

    2005-01-01

    [figure removed for brevity, see original site] Annotated Spirit View of Phobos Eclipse, Sol 675

    NASA's Mars Exploration Rover Spirit observed the Martian moon Phobos entering the shadow of Mars during the night of the rover's 675th sol (Nov. 27, 2005). The panoramic camera captured 16 images, spaced 10 seconds apart, covering the period from when Phobos was in full sunlight to when it was entirely in shadow. As with our own Moon during lunar eclipses on Earth, even when in the planet's shadow, Phobos was not entirely dark. The small amount of light still visible from Phobos is a kind of 'Mars-shine' -- sunlight reflected through Mars' atmosphere and into the shadowed region.

    This view is a time-lapse composite of images taken 20 seconds apart, showing the movement of Phobos from left to right. (At 10 seconds apart, the images of the moon overlap each other.) Scientists are using information about the precise timing of Martian moon eclipses gained from observations such as these to refine calculations about the orbital path of Phobos. The precise position of Phobos will be important to any future spacecraft taking detailed pictures of the moon or landing on its surface.

  20. First results from the NASA WB-57 airborne observations of the Great American 2017 Total Solar Eclipse

    NASA Astrophysics Data System (ADS)

    Caspi, Amir; Tsang, Constantine; DeForest, Craig; Seaton, Daniel B.; Bryans, Paul; Tomczyk, Steven; Burkepile, Joan; Judge, Phil; DeLuca, Edward E.; Golub, Leon; Gallagher, Peter T.; Zhukov, Andrei; West, Matthew; Durda, Daniel D.; Steffl, Andrew J.

    2017-08-01

    Total solar eclipses present rare opportunities to study the complex solar corona, down to altitudes of just a few percent of a solar radius above the surface, using ground-based and airborne observatories that would otherwise be dominated by the intense solar disk and high sky brightness. Studying the corona is critical to gaining a better understanding of physical processes that occur on other stars and astrophysical objects, as well as understanding the dominant driver of space weather that affects human assets at Earth and elsewhere. For example, it is still poorly understood how the corona is heated to temperatures of 1-2 MK globally and up to 5-10 MK above active regions, while the underlying chromosphere is 100 times cooler; numerous theories abound, but are difficult to constrain due to the limited sensitivities and cadences of prior measurements. The origins and stability of coronal fans, and the extent of their reach to the middle and outer corona, are also not well known, limited in large part by sensitivities and fields of view of existing observations.Airborne observations during the eclipse provide unique advantages; by flying in the stratosphere at altitudes of 50 kft or higher, they avoid all weather, the seeing quality is enormously improved, and additional wavelengths such as near-IR also become available due to significantly reduced water absorption. For an eclipse, an airborne observatory can also follow the shadow, increasing the total observing time by 50% or more.We present the first results from airborne observations of the 2017 Great American Total Solar Eclipse using two of NASA's WB-57 research aircraft, each equipped with two 8.7" telescopes feeding high-sensitivity visible (green-line) and near-IR (3-5 µm) cameras operating at high cadence (30 Hz) with ~3 arcsec/pixel platescale and ±3 R_sun fields of view. The aircraft will fly along the eclipse path, separated by ~90 km, to observe a summed ~8 minutes of totality in both visible and

  1. The Citizen CATE Experiment for the 2017 Total Solar Eclipse

    NASA Astrophysics Data System (ADS)

    Penn, M. J.

    2015-12-01

    The path of the total solar eclipse of 21 August 2017 passes over about 10 million homes in the USA. Tens of millions more people will travel to the path of totality to view the eclipse first-hand. Using TV and the internet broadcasts, hundreds of millions of people will watch the eclipse, making the event the most viewed astronomical event in the history of mankind. The Citizen Continental-America Telescopic Eclipse (CATE) Experiment for 2017 is being developed at the National Solar Observatory in partnership with universities, schools, astronomy clubs, and corporations. The CATE experiment will use more than 60 identical telescopes equipped with digital cameras positioned from Oregon to South Carolina to image the solar corona. The project will then splice these images together to show the corona during a 90-minute period, revealing for the first time the plasma dynamics of the inner solar corona. The goals for the highly leveraged CATE experiment are diverse and range from providing an authentic STEM research experience for students and lifelong learners, to making state-of-the-art solar coronal observations of the plasma dynamics of coronal polar plumes, to increasing the US scientific literacy. A key goal of this experiment is to donate the telescope and camera system to the volunteer who collects data with it during the total eclipse. The instrument will be then used for a variety of follow-up citizen science projects in astronomy, ranging from solar to cometary to variable star observations. For this reason no government funding is being sought for the equipment costs, but rather private and corporate sources are being developed. The data collected for the 2017 eclipse will be freely available to the scientific, education and amateur astronomy communities. Crowd sourcing the data collection is an essential part of this project, as there are not enough solar physicists in this country to collect these observations. Finally, each site is expected to collect

  2. C6, C7, and C8 perfluoroalkyl-substituted phosphinic acids.

    PubMed

    Singh, R P; Shreeve, J M

    2000-04-17

    Reaction of red phosphorus with RfI in a 1:2 molar ratio at 230 degrees C led to the formation of a mixture of (Rf)2PI and (Rf)PI2 (Rf = C6F13, C7F15, C8F17) in about a 70:30 ratio, respectively. These mixtures were separated by vacuum distillation. (Rf)2PI (Rf = C6F13, C7F15) are yellow liquids whereas (C8F17)2PI is a yellow solid. Oxidation of (Rf)2PI with excess NO2 led to (Rf)2P(O)OH (Rf = C6F13, C7F15, C8F17) in > 90% isolated yields after aqueous hydrolysis of the anhydride intermediates. These highly fluorinated phosphinic acids are white solids with sharp melting points and are highly soluble in methyl sulfoxide (DMSO) and 1,1,2-trichlorotrifluoroethane. However, solubility in chloroform and methylene dichloride is low. These perfluoroalkylphosphinic acids were characterized by IR, NMR (1H, 19F, and 31P), and mass spectra and elemental analysis.

  3. SDO Sees Spring Eclipse April, 3

    NASA Image and Video Library

    2017-12-08

    NASA image captured April 3, 2011 Twice a year, SDO enters an eclipse season where the spacecraft slips behind Earth for up to 72 minutes a day. Unlike the crisp shadow one sees on the sun during a lunar eclipse, Earth's shadow has a variegated edge due to its atmosphere, which blocks the sun light to different degrees depending on its density. Also, light from brighter spots on the sun may make it through, which is why some solar features extend low into Earth's shadow. Credit: NASA/GSFC/SDO 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

  4. SDO Sees Spring Eclipse, April 2

    NASA Image and Video Library

    2017-12-08

    NASA image captured April 2, 2011 Twice a year, SDO enters an eclipse season where the spacecraft slips behind Earth for up to 72 minutes a day. Unlike the crisp shadow one sees on the sun during a lunar eclipse, Earth's shadow has a variegated edge due to its atmosphere, which blocks the sun light to different degrees depending on its density. Also, light from brighter spots on the sun may make it through, which is why some solar features extend low into Earth's shadow. Credit: NASA/GSFC/SDO 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

  5. SDO Sees Spring Eclipse, April 1

    NASA Image and Video Library

    2017-12-08

    NASA image captured April 1, 2011 Twice a year, SDO enters an eclipse season where the spacecraft slips behind Earth for up to 72 minutes a day. Unlike the crisp shadow one sees on the sun during a lunar eclipse, Earth's shadow has a variegated edge due to its atmosphere, which blocks the sun light to different degrees depending on its density. Also, light from brighter spots on the sun may make it through, which is why some solar features extend low into Earth's shadow. Credit: NASA/GSFC/SDO 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

  6. Response of Cassava canopy to mid-day pseudo sunrise induced by solar eclipse.

    PubMed

    Latha, R; Murthy, B S

    2013-07-01

    Variations in CO(2) concentration over a cassava canopy were measured during a solar eclipse at Thiruvananthapuram, India. The analysis presented attempts to differentiate between the eclipse effect and the possible effect of thick clouds, taking CO(2) as a proxy for photosynthesis. CO(2) and water vapor were measured at a rate of 10 Hz, and radiation at 1 Hz, together with other meteorological parameters. A rapid reduction in CO(2) observed post-peak eclipse, due apparently to intense photosynthesis, appears similar to what happens at daybreak/post-sunrise. The increase in CO(2) (4 ppm) during peak eclipse, with radiation levels falling below the photosynthesis cut-off for cassava, indicates domination of respiration due to the light-limiting conditions.

  7. Response of Cassava canopy to mid-day pseudo sunrise induced by solar eclipse

    NASA Astrophysics Data System (ADS)

    Latha, R.; Murthy, B. S.

    2013-07-01

    Variations in CO2 concentration over a cassava canopy were measured during a solar eclipse at Thiruvananthapuram, India. The analysis presented attempts to differentiate between the eclipse effect and the possible effect of thick clouds, taking CO2 as a proxy for photosynthesis. CO2 and water vapor were measured at a rate of 10 Hz, and radiation at 1 Hz, together with other meteorological parameters. A rapid reduction in CO2 observed post-peak eclipse, due apparently to intense photosynthesis, appears similar to what happens at daybreak/post-sunrise. The increase in CO2 (4 ppm) during peak eclipse, with radiation levels falling below the photosynthesis cut-off for cassava, indicates domination of respiration due to the light-limiting conditions.

  8. The total solar eclipse of 2010 July 11

    NASA Astrophysics Data System (ADS)

    McGee, H.; James, N.; Mason, J.

    2010-08-01

    The solar eclipse of 2010 July 11 always promised to be a logistical nightmare to observe. The Moon's shadow first touched the Earth in the southern Pacific, encountering land at Mangaia in the Cook Islands only after 1450km of open ocean. The narrow track of totality then swung northeast, passing tantalisingly close to the islands of Tahiti and Moorea, which experienced a 98% partial eclipse. Beyond Tahiti the track crossed the Tuamotu archipelago of French Polynesia - thousands of tiny coral atolls, of which very few are inhabited, and even fewer have airstrips that make them accessible to visitors.

  9. New Light-Time Curve of Eclipsing Binary AM Leo

    NASA Astrophysics Data System (ADS)

    Gorda, S. Yu.; Matveeva, E. A.

    2017-12-01

    We present 72 photoelectric and CCD times of minima of eclipsing binary AM Leo obtained mainly during at Kourovka Astronomical Observatory of the Ural Federal University in Russia. We obtained new values of period of 50.5 years and eccentricity of 0.28 of the orbit of the eclipsing pair around the mass center of the system AM Leo with the third body. These results have been received taking into account the times of minima taken from literature and obtained from to .

  10. Changes in Latitude, Changes in Attitude: U.S. Naval Observatory Observations of Solar Eclipses 1869 to the Present

    NASA Astrophysics Data System (ADS)

    Chizek Frouard, Malynda R.; Towne, Linda; Kaplan, George H.

    2017-01-01

    In anticipation of the 2017 August 21 total solar eclipse over the continental United States, the history of U.S. Naval Observatory eclipse observations illustrates the changes in science, technology, and policy over the past 148 years.USNO eclipse observations began in 1869, when staff traveled to Des Moines, Iowa and the Bering Strait to look for intra-mercurial planets and to observe the solar corona. During the golden age of eclipse expeditions, the USNO officially participated in a dozen expeditions between 1869 and 1929. Seven of these expeditions were to US locations: 1869 in Iowa; 1878 in Colorado, Wyoming, and Texas; 1880 in California; 1900 in Georgia and North Carolina; 1918 in Oregon; 1923 in California; and 1925 in New York. A total solar eclipse has not traced a path across the width of the continental US since 1918 although several eclipses have passed over parts of the US since then.A few official expeditions occurred later in the 20th century to measure the solar diameter, including a total eclipse in the northwest US in 1979 and an annular eclipse across the southeast in 1984. However, observations began transitioning to mostly personal adventures as individual astronomers arranged unofficial trips.Historians can use the USNO Multi-year Interactive Computer Almanac (MICA) to compute local circumstances for solar eclipses world-wide starting with the annual eclipse of 1800 April 24, which was visible from Alaska. Those looking to make history in 2017 may consult the USNO 2017 August 21 Solar Eclipse Resource page (http://aa.usno.navy.mil/data/docs/Eclipse2017.php).

  11. Investigations of electron attachment to the perfluorocarbon molecules c-C4F8, 2-C4F8, 1,3 C4F6, and c-C5F8

    NASA Astrophysics Data System (ADS)

    Feil, Stefan; Märk, Tilmann D.; Mauracher, Andreas; Scheier, Paul; Mayhew, Chris A.

    2008-11-01

    Non-dissociative and dissociative electron attachment to a series of gas-phase perfluorocarbons (PFCs), namely octafluorocyclobutane, c-C4F8, octafluorobut-2-ene (perfluoro-2-butene), 2-C4F8, hexafluorobuta-1,3-diene (1,3 perfluorobutadiene), 1,3 C4F6, and octafluorocyclopentene (perfluorocyclopentene), c-C5F8, of importance to technological plasmas, have been investigated using two different, but complimentary, instruments available in Innsbruck over the electron energy range 0-20 eV. Anion yields as a function of electron energy have been recorded, with the positions and intensities of the electron attachment resonances being determined. One of these instruments is a double focusing sector field mass spectrometer (VG-ZAB-2SEQ), which has been used for measurements requiring high sensitivity and for obtaining accurate relative anion yields. It has also been used to determine the electron detachment lifetimes of the parent anions under various accelerating voltages, and these results are also presented. The second instrument (CELIA) is a trochoidal electron monochromator coupled to a quadrupole mass filter with a pulse counting system for detecting product anionic species. This provides a much higher energy resolution than the VG-ZAB, which makes it a better instrument to investigate narrow energy resonances close to 0 eV. The results of anion yields, peak positions and the relative intensities presented in this paper are compared with previous data of electron attachment to the above PFCs, including investigations by Professor Eugen Illenberger.

  12. A model of V356 Sagittarii. [eclipsing binary star

    NASA Technical Reports Server (NTRS)

    Wilson, R. E.; Caldwell, C. N.

    1978-01-01

    It is pointed out that V356 Sgr is an abnormal member of the Algol class of binaries. According to Popper (1955), the primary component is of spectral type B3V and is rotating rapidly, while the secondary is of type A2II and is rotating at least approximately in synchronism with the orbital motion. The system is either semidetached or quite near to being semidetached. The main anomalies are related to the ratio of eclipse depths, the very small reflection effect of the light curves, differences between the duration of the primary and the secondary eclipse, and the unusual characteristics of the primary eclipse. It is concluded that the lack of agreement between theory and observation can be due only to an important attribute of the binary which has not yet been incorporated into the theory. The peculiarities can most reasonably be explained in terms of a geometrically and optically thick disk which surrounds the primary component.

  13. 2017 Solar Eclipse, Ames Research Center

    NASA Image and Video Library

    2017-08-21

    Taking a break from their duties at the Ames Vertical Gun Range to look up at the eclipse over Ames Research Center in Mountain View are from left to right are Alfredo "Freddie" Perez, Chuck Cornelison, Don Bowling, Adam Parish

  14. Solar eclipse demonstrating the importance of photochemistry in new particle formation

    NASA Astrophysics Data System (ADS)

    Jokinen, Tuija; Kontkanen, Jenni; Lehtipalo, Katrianne; Manninen, Hanna E.; Aalto, Juho; Porcar-Castell, Albert; Garmash, Olga; Nieminen, Tuomo; Ehn, Mikael; Kangasluoma, Juha; Junninen, Heikki; Levula, Janne; Duplissy, Jonathan; Ahonen, Lauri R.; Rantala, Pekka; Heikkinen, Liine; Yan, Chao; Sipilä, Mikko; Worsnop, Douglas R.; Bäck, Jaana; Petäjä, Tuukka; Kerminen, Veli-Matti; Kulmala, Markku

    2017-04-01

    Solar eclipses provide unique possibilities to investigate atmospheric processes, such as new particle formation (NPF), important to the global aerosol load and radiative balance. The temporary absence of solar radiation gives particular insight into different oxidation and clustering processes leading to NPF. This is crucial because our mechanistic understanding on how NPF is related to photochemistry is still rather limited. During a partial solar eclipse over Finland in 2015, we found that this phenomenon had prominent effects on atmospheric on-going NPF. During the eclipse, the sources of aerosol precursor gases, such as sulphuric acid and nitrogen- containing highly oxidised organic compounds, decreased considerably, which was followed by a reduced formation of small clusters and nanoparticles and thus termination of NPF. After the eclipse, aerosol precursor molecule concentrations recovered and re-initiated NPF. Our results provide direct evidence on the key role of the photochemical production of sulphuric acid and highly oxidized organic compounds in maintaining atmospheric NPF. Our results also explain the rare occurrence of this phenomenon under dark conditions, as well as its seemingly weak connection with atmospheric ions.

  15. Solar eclipse demonstrating the importance of photochemistry in new particle formation

    PubMed Central

    Jokinen, Tuija; Kontkanen, Jenni; Lehtipalo, Katrianne; Manninen, Hanna E.; Aalto, Juho; Porcar-Castell, Albert; Garmash, Olga; Nieminen, Tuomo; Ehn, Mikael; Kangasluoma, Juha; Junninen, Heikki; Levula, Janne; Duplissy, Jonathan; Ahonen, Lauri R.; Rantala, Pekka; Heikkinen, Liine; Yan, Chao; Sipilä, Mikko; Worsnop, Douglas R.; Bäck, Jaana; Petäjä, Tuukka; Kerminen, Veli-Matti; Kulmala, Markku

    2017-01-01

    Solar eclipses provide unique possibilities to investigate atmospheric processes, such as new particle formation (NPF), important to the global aerosol load and radiative balance. The temporary absence of solar radiation gives particular insight into different oxidation and clustering processes leading to NPF. This is crucial because our mechanistic understanding on how NPF is related to photochemistry is still rather limited. During a partial solar eclipse over Finland in 2015, we found that this phenomenon had prominent effects on atmospheric on-going NPF. During the eclipse, the sources of aerosol precursor gases, such as sulphuric acid and nitrogen- containing highly oxidised organic compounds, decreased considerably, which was followed by a reduced formation of small clusters and nanoparticles and thus termination of NPF. After the eclipse, aerosol precursor molecule concentrations recovered and re-initiated NPF. Our results provide direct evidence on the key role of the photochemical production of sulphuric acid and highly oxidized organic compounds in maintaining atmospheric NPF. Our results also explain the rare occurrence of this phenomenon under dark conditions, as well as its seemingly weak connection with atmospheric ions. PMID:28374761

  16. Measuring the Number of M Dwarfs per M Dwarf Using Kepler Eclipsing Binaries

    NASA Astrophysics Data System (ADS)

    Shan, Yutong; Johnson, John A.; Morton, Timothy D.

    2015-11-01

    We measure the binarity of detached M dwarfs in the Kepler field with orbital periods in the range of 1-90 days. Kepler’s photometric precision and nearly continuous monitoring of stellar targets over time baselines ranging from 3 months to 4 years make its detection efficiency for eclipsing binaries nearly complete over this period range and for all radius ratios. Our investigation employs a statistical framework akin to that used for inferring planetary occurrence rates from planetary transits. The obvious simplification is that eclipsing binaries have a vastly improved detection efficiency that is limited chiefly by their geometric probabilities to eclipse. For the M-dwarf sample observed by the Kepler Mission, the fractional incidence of eclipsing binaries implies that there are {0.11}-0.04+0.02 close stellar companions per apparently single M dwarf. Our measured binarity is higher than previous inferences of the occurrence rate of close binaries via radial velocity techniques, at roughly the 2σ level. This study represents the first use of eclipsing binary detections from a high quality transiting planet mission to infer binary statistics. Application of this statistical framework to the eclipsing binaries discovered by future transit surveys will establish better constraints on short-period M+M binary rate, as well as binarity measurements for stars of other spectral types.

  17. Eclipse Photo/Video Coverage

    NASA Image and Video Library

    2017-08-21

    On Monday, Aug. 21, NASA provided coast-to-coast coverage of the solar eclipse across America – featuring views of the phenomenon from unique vantage points, including from the ground, from aircraft, and from spacecraft including the ISS, during a live broadcast seen on NASA Television and the agency’s website. This is footage from the Kennedy Space Center Visitor Complex, KARS Park at Kennedy, and the Vehicle Assembly Building.

  18. 15 CFR 8c.60 - Communications.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 15 Commerce and Foreign Trade 1 2010-01-01 2010-01-01 false Communications. 8c.60 Section 8c.60 Commerce and Foreign Trade Office of the Secretary of Commerce ENFORCEMENT OF NONDISCRIMINATION ON THE BASIS OF HANDICAP IN PROGRAMS OR ACTIVITIES CONDUCTED BY THE DEPARTMENT OF COMMERCE § 8c.60...

  19. On the development and applications of automated searches for eclipsing binary stars

    NASA Astrophysics Data System (ADS)

    Devor, Jonathan

    Eclipsing binary star systems provide the most accurate method of measuring both the masses and radii of stars. Moreover, they enable testing tidal synchronization and circularization theories, as well as constraining models of stellar structure and dynamics. With the recent availability of large-scale multi-epoch photometric datasets, we are able to study eclipsing binary stars en masse. In this thesis, we analyzed 185,445 light curves from ten TrES fields, and 218,699 light curves from the OGLE II bulge fields. In order to manage such large quantities of data, we developed a pipeline with which we systematically identified eclipsing binaries, solved for their geometric orientations, and then found their components' absolute properties. Following this analysis, we assembled catalogs of eclipsing binaries with their models, computed statistical distributions of their properties, and located rare cases for further follow-up. Of particular importance are low-mass eclipsing binaries, which are rare, yet critical for resolving the ongoing mass-radius discrepancy between theoretical models and observations. To this end, we have discovered over a dozen new low-mass eclipsing binary candidates, and spectroscopically confirmed the masses of five of them. One of these confirmed candidates, T-Lyr1-17236, is especially interesting because of its uniquely long orbital period. We examined T-Lyr1-17236 in detail and found that it is consistent with the magnetic disruption hypothesis for explaining the observed mass-radius discrepancy. Both the source code of our pipeline and the complete list of our candidates are freely available.

  20. Demonstrations to Teach Electricity and Safely Observe a Solar Eclipse

    NASA Astrophysics Data System (ADS)

    Reiff, P. H.

    2016-12-01

    Electricity and magnetism are often difficult to understand because they are invisible. We will demonstrate various ways to visualize electric fields. We will play music on a plasma discharge from a Tesla coil, create static charge on balloons with hair, and store charge using a Leyden jar. We will also show safe ways to observe a solar eclipse, which is critical for the upcoming August 21, 2017 eclipse.

  1. A Catalog of Eclipsing Binaries and Variable Stars Observed with ASTEP 400 from Dome C, Antarctica

    NASA Astrophysics Data System (ADS)

    Chapellier, E.; Mékarnia, D.; Abe, L.; Guillot, T.; Agabi, K.; Rivet, J.-P.; Schmider, F.-X.; Crouzet, N.; Aristidi, E.

    2016-10-01

    We used the large photometric database of the ASTEP program, whose primary goal was to detect exoplanets in the southern hemisphere from Antarctica, to search for eclipsing binaries (EcBs) and variable stars. 673 EcBs and 1166 variable stars were detected, including 31 previously known stars. The resulting online catalogs give the identification, the classification, the period, and the depth or semi-amplitude of each star. Data and light curves for each object are available at http://astep-vo.oca.eu.

  2. 15 CFR 8c.40 - Employment.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 15 Commerce and Foreign Trade 1 2010-01-01 2010-01-01 false Employment. 8c.40 Section 8c.40... BASIS OF HANDICAP IN PROGRAMS OR ACTIVITIES CONDUCTED BY THE DEPARTMENT OF COMMERCE § 8c.40 Employment... discrimination in employment under any program or activity conducted by the agency. The definitions, requirements...

  3. Observation of the total solar eclipse on 21 June 2001 in Zambia

    NASA Astrophysics Data System (ADS)

    Takahashi, Noritsugu; Yumoto, Kiyohumi; Ichimoto, Kiyoshi

    2002-04-01

    On 21 June 2001, path of totality in Angola, Zambia, Zimbabwe, Mozambique, and Madagascar in Africa. The Japan Scientific Observation Team, consisting primarily of the members of the Solar Eclipse Subcommittee of the Committee for International Collaboration in Astronomy of the Science Council of JAPAN, visited Lusaka in Zambia to observe the total solar eclipse. Blessed with fine weather, the observation was successful. The outline of the influence of solar eclipse on the terrestrial magnetism, polarization of the flash spectrum, and other observation data, as well as the way educational activities were carried out, are reported.

  4. The Eclipse of the Sun from 29 March 2006

    NASA Astrophysics Data System (ADS)

    Coca, Sergiu; Gaina, Alex; Stefanco, Alex

    The internet post include: The curve of the temperature during the day of the Eclipse of the Sun from 29 march 2006, Few photographs of the eclipse made in Chisinau (The Republic of Moldova)(47 Deg.03 Min. N.L., 28 Deg. 46 Min. E.L.). A miscellaneous photo of the comet Halle -Bopp made by FED-5B (No. 101962, manufactured in 1979) is presented also. For translation of the texts from Russian to 10 languages use: http://www.translate.ru/text.asp?lang=ru

  5. Time Series Observations of the 2015 Eclipse of b Persei (not beta Persei) (Abstract)

    NASA Astrophysics Data System (ADS)

    Collins, D. F.

    2016-06-01

    (Abstract only) The bright (V = 4.6) ellipsoidal variable b Persei consists of a close non-eclipsing binary pair that shows a nearly sinusoidal light curve with a ~1.5 day period. This system also contains a third star that orbits the binary pair every 702 days. AAVSO observers recently detected the first ever optical eclipse of A-B binary pair by the third star as a series of snapshots (D. Collins, R. Zavala, J. Sanborn - AAVSO Spring Meeting, 2013); abstract published in Collins, JAAVSO, 41, 2, 391 (2013); b Per mis-printed as b Per therein. A follow-up eclipse campaign in mid-January 2015 recorded time-series observations. These new time-series observations clearly show multiple ingress and egress of each component of the binary system by the third star over the eclipse duration of 2 to 3 days. A simulation of the eclipse was created. Orbital and some astrophysical parameters were adjusted within constraints to give a reasonable fit to the observed light curve.

  6. A Comprehensive Catalog of Galactic Eclipsing Binary Stars with Eccentric Orbits Based on Eclipse Timing Diagrams

    NASA Astrophysics Data System (ADS)

    Kim, C.-H.; Kreiner, J. M.; Zakrzewski, B.; Ogłoza, W.; Kim, H.-W.; Jeong, M.-J.

    2018-04-01

    A comprehensive catalog of 623 galactic eclipsing binary (EB) systems with eccentric orbits is presented with more than 2830 times of minima determined from the archived photometric data by various sky-survey projects and new photometric measurements. The systems are divided into two groups according to whether the individual system has a GCVS name or not. All the systems in both groups are further classified into three categories (D, A, and A+III) on the basis of their eclipse timing diagrams: 453 D systems showing just constantly displaced secondary minima, 139 A systems displaying only apsidal motion (AM), and 31 A+III systems exhibiting both AM and light-time effects. AM parameters for 170 systems (A and A+III systems) are consistently calculated and cataloged with basic information for all systems. Some important statistics for the AM parameters are discussed and compared with those derived for the eccentric EB systems in the Large and Small Magellanic Clouds.

  7. Derivation of Heliophysical Scientific Data from Amateur Observations of Solar Eclipses

    NASA Astrophysics Data System (ADS)

    Stoev, A. D.; Stoeva, P. V.

    2006-03-01

    The basic scientific aims and observational experiments included in the complex observational program - Total Solar Eclipse '99 - are described in the work. Results from teaching and training students of total solar eclipse (TSE) observation in the Public Astronomical Observatory (PAO) in Stara Zagora and their selection for participation in different observational teams are also discussed. During the final stage, a special system of methods for investigation of the level of pretensions (the level of ambition as to what he/she feels capable of achieving in the context of problem solving/observation) of the students is applied. Results obtained from the observational experiments are interpreted mainly in the following themes: Investigation of the structure of the white-light solar corona and evolution of separate coronal elements during the total phase of the eclipse; Photometry of the white-light solar corona and specific emission lines; Meteorological, actinometrical and optical atmospheric investigations; Astrometry of the Moon during the phase evolution of the eclipse; Biological and behavioral reactions of highly organized colonies (ants and bats) during the eclipse. It is also shown that data processing, observational results and their interpretation, presentation and publishing in specialized and amateur editions is a peak in the independent creative activity of students and amateur astronomers. This enables students from the Astronomy schools at Public Astronomical Observatories and Planetariums (PAOP) to develop creative skills, emotional - volitional personal qualities, orientation towards scientific work, observations and experiments, and build an effective scientific style of thinking.

  8. Eclipse studies of the dwarf nova EX Draconis

    NASA Astrophysics Data System (ADS)

    Baptista, R.; Catalán, M. S.; Costa, L.

    2000-08-01

    We report on V and R high-speed photometry of the dwarf nova EX Draconis (EX Dra) in quiescence and in outburst. The analysis of the outburst light curves indicates that the outbursts do not start in the outer disc regions. The disc expands during the rise to maximum and shrinks during decline and along the following quiescent period. The decrease in brightness at the later stages of the outburst is due to the fading of the light from the inner disc regions. At the end of two outbursts the system was seen to go through a phase of lower brightness, characterized by an out-of-eclipse level ~=15 per cent lower than the typical quiescent level and by the fairly symmetric eclipse of a compact source at disc centre with little evidence of a bright spot at disc rim. New eclipse timings were measured from the light curves taken in quiescence and a revised ephemeris was derived. The residuals with respect to the linear ephemeris are well described by a sinusoid of amplitude 1.2min and period ~=4yr and are possibly related to a solar-like magnetic activity cycle in the secondary star. Eclipse phases of the compact central source and of the bright spot were used to derive the geometry of the binary. By constraining the gas stream trajectory to pass through the observed position of the bright spot, we find q=0.72+/-0.06 and i85+3-2 degrees. The binary parameters were estimated by combining the measured mass ratio with the assumption that the secondary star obeys an empirical main-sequence mass-radius relation. We find M1=0.75+/-0.15Msolar and M2=0.54+/-0.10Msolar. The results indicate that the white dwarf at disc centre is surrounded by an extended and variable atmosphere or boundary layer of at least three times its radius and a temperature of T~=28000K. The fluxes at mid-eclipse yield an upper limit to the contribution of the secondary star and lead to a lower limit photometric parallax distance of D=290+/-80pc. The fluxes of the secondary star are well-matched by those of a

  9. Apsidal motion in eccentric eclipsing binaries: TV Ceti and V451 Ophiuchi

    NASA Astrophysics Data System (ADS)

    Wolf, M.; Diethelm, R.; Hornoch, K.

    2001-07-01

    Several new times of minimum light recorded with photoelectric means have been gathered for two bright eccentric eclipsing binaries TV Cet (P = 9fd1 , e = 0.055) and V451 Oph (P = 2fd2 , e = 0.013). Analysis of all available eclipse timings of TV Ceti has revealed a small motion of the line of apsides of dot ω = 0.000 30 +/- 0.000 08 deg cycle-1, corresponding to an apsidal period of U = 30 000 +/- 8 000 years. The contribution from the general relativity effects is dominant (dot ωrel/dot ω ~ 80 % ). In this system, the third body on an eccentric orbit with a period of 28.5 years is also predicted. The more precise values for the apsidal motion elements were computed for V451 Oph, where apsidal motion with a period of 170 +/- 5 years was confirmed. The corresponding internal structure constants log k2 were derived. Some of the observations reported in this paper were obtained at the South Africa Astronomical Observatory, Sutherland, South Africa.

  10. Through the Eyes of NASA: NASA's 2017 Eclipse Education Progam

    NASA Astrophysics Data System (ADS)

    Mayo, L.

    2017-12-01

    Over the last three years, NASA has been developing plans to bring the August 21st total solar eclipse to the nation, "as only NASA can", leveraging its considerable space assets, technology, scientists, and its unmatched commitment to science education. The eclipse, long anticipated by many groups, represents the largest Big Event education program that NASA has ever undertaken. It is the latest in a long string of successful Big Event international celebrations going back two decades including both transits of Venus, three solar eclipses, solar maximum, and mission events such as the MSL/Curiosity landing on Mars, and the launch of the Lunar Reconnaissance Orbiter (LRO) to name a few. This talk will detail NASA's program development methods, strategic partnerships, and strategies for using this celestial event to engage the nation and improve overall science literacy.

  11. "Dilute & shoot" approach for rapid determination of trace amounts of nicotine in zero-level e-liquids by reversed phase liquid chromatography and hydrophilic interactions liquid chromatography coupled with tandem mass spectrometry-electrospray ionization.

    PubMed

    Kubica, Paweł; Kot-Wasik, Agata; Wasik, Andrzej; Namieśnik, Jacek

    2013-05-10

    Two analytical procedures are proposed where HILIC and RPLC techniques are coupled with tandem mass spectrometry detection for rapid determination of trace amounts of nicotine in zero-level liquids for electronic cigarettes. Samples are prepared on the basis of the approach "dilute & shoot" which makes this important step quick and not complicated. The chromatographic separation was carried out on a Zorbax XDB column (RPLC method) and Ascentis Si column (HILIC mode). Within-run precisions (CVs) measured at three concentration levels were as follows: 0.73%, 0.98% and 1.44% for RPLC method and 1.39%, 1.44% and 0.57% (HILIC mode). Between-run CVs were as follows: 1.94%, 1.02% and 1.22% for RPLC mode and 1.49%, 1.20% and 1.22% for HILIC mode. The detection limits of RPLC and HILIC modes were 4.08 and 3.90 ng/mL respectively. The proposed procedures are rapid, not complicated, sensitive and are suitable for fast determination of trace amounts of nicotine in zero-level liquids for electronic cigarettes. Copyright © 2013 Elsevier B.V. All rights reserved.

  12. Bringing the Great American Eclipse of 2017 to Audiences across the Nation

    NASA Astrophysics Data System (ADS)

    Young, C. A.; Mayo, L.; Cline, T. D.; Ng, C.; Stephenson, B. E.

    2015-12-01

    The August 21, 2017 eclipse across America will be seen by an estimated 500 million people from northern Canada to South America as well as parts of western Europe and Africa. Through This "Great American Eclipse" NASA in partnership with Google, the American Parks Network, American Astronomical Society, the Astronomical League, and numerous other science, education, outreach, and public communications groups and organizations will develop the approaches, resources, partnerships, and technology applications necessary to bring the excitement and the science of the August 21st, 2017 total solar eclipse across America to formal and informal audiences in the US and around the world. This effort will be supported by the highly visible and successful Sun Earth Days program and will be the main theme for Sun-Earth Days 2017.This presentation will discuss NASA's education and communication plans for the eclipse and will detail a number of specific programs and partnerships being leveraged to enhance our reach and impact.

  13. A recent time of minimum for and atmospheric-eclipse in the ultraviolet spectrum of the Wolf-Rayet eclipsing binary V444 Cygni

    NASA Technical Reports Server (NTRS)

    Eaton, J. E.; Cherepashchuk, A. M.; Khaliullin, K. F.

    1982-01-01

    The 1200-1900 angstrom region and fine error sensor observations in the optical for V444 Cyg were continuously observed. More than half of a primary minimum and almost a complete secondary minimum were observed. It is found that the time of minimum for the secondary eclipse is consistent with that for primary eclipse, and the ultraviolet times of minimum are consistent with the optical ones. The spectrum shows a considerable amount of phase dependence. The general shaps and depths of the light curves for the FES signal and the 1565-1900 angstrom continuum are similar to those for the blue continuum. The FES, however, detected an atmospheric eclipse in line absorption at about the phase the NIV absorption was strongest. It is suggested that there is a source of continuum absorption shortward of 1460 angstrom which exists throughout a large part of the extended atmosphere and which, by implication, must redden considerably the ultraviolet continuua of WN stars. A fairly high degree of ionization for the inner part of the WN star a atmosphere is implied.

  14. ISAAC Photometric Comparison of ECLIPSE Jitter and the ORAC-DR Equivalent Recipe for ISAAC

    NASA Astrophysics Data System (ADS)

    Currie, M. J.

    2005-12-01

    Motivated by a request from astronomers demanding accurate and consistent infrared photometry, I compare the photometry and quality of mosaics generated by the ECLIPSE jitter task and the ORAC-DR JITTER_SELF_FLAT recipe in two fields. The current (v4.9.0) ECLIPSE produces photometry a few percent fainter than ORAC-DR; the systematic trend with magnitude seen in v4.4.1 is now removed. Random errors arising from poor flat-fielding are not resolved. ECLIPSE generates noisier mosaics; ORAC-DR has poorer bias removal in crowded fields and defaults to larger mosaics. ORAC-DR runs a few times slower than ECLIPSE, but its recipe development is measured in weeks, not years.

  15. Stonehenge: A Simple and Accurate Predictor of Lunar Eclipses

    NASA Astrophysics Data System (ADS)

    Challener, S.

    1999-12-01

    Over the last century, much has been written about the astronomical significance of Stonehenge. The rage peaked in the mid to late 1960s when new computer technology enabled astronomers to make the first complete search for celestial alignments. Because there are hundreds of rocks or holes at Stonehenge and dozens of bright objects in the sky, the quest was fraught with obvious statistical problems. A storm of controversy followed and the subject nearly vanished from print. Only a handful of these alignments remain compelling. Today, few astronomers and still fewer archaeologists would argue that Stonehenge served primarily as an observatory. Instead, Stonehenge probably served as a sacred meeting place, which was consecrated by certain celestial events. These would include the sun's risings and settings at the solstices and possibly some lunar risings as well. I suggest that Stonehenge was also used to predict lunar eclipses. While Hawkins and Hoyle also suggested that Stonehenge was used in this way, their methods are complex and they make use of only early, minor, or outlying areas of Stonehenge. In contrast, I suggest a way that makes use of the imposing, central region of Stonehenge; the area built during the final phase of activity. To predict every lunar eclipse without predicting eclipses that do not occur, I use the less familiar lunar cycle of 47 lunar months. By moving markers about the Sarsen Circle, the Bluestone Circle, and the Bluestone Horseshoe, all umbral lunar eclipses can be predicted accurately.

  16. Meteorological effects of the solar eclipse of 20 March 2015: analysis of UK Met Office automatic weather station data and comparison with automatic weather station data from the Faroes and Iceland

    PubMed Central

    Penman, John; Jónsson, Trausti; Bigg, Grant R.; Björnsson, Halldór; Sjúrðarson, Sølvi; Hansen, Mads A.; Cappelen, John; Bryant, Robert G.

    2016-01-01

    Here, we analyse high-frequency (1 min) surface air temperature, mean sea-level pressure (MSLP), wind speed and direction and cloud-cover data acquired during the solar eclipse of 20 March 2015 from 76 UK Met Office weather stations, and compare the results with those from 30 weather stations in the Faroe Islands and 148 stations in Iceland. There was a statistically significant mean UK temperature drop of 0.83±0.63°C, which occurred over 39 min on average, and the minimum temperature lagged the peak of the eclipse by about 10 min. For a subset of 14 (16) relatively clear (cloudy) stations, the mean temperature drop was 0.91±0.78 (0.31±0.40)°C but the mean temperature drops for relatively calm and windy stations were almost identical. Mean wind speed dropped significantly by 9% on average during the first half of the eclipse. There was no discernible effect of the eclipse on the wind-direction or MSLP time series, and therefore we can discount any localized eclipse cyclone effect over Britain during this event. Similar changes in air temperature and wind speed are observed for Iceland, where conditions were generally clearer, but here too there was no evidence of an eclipse cyclone; in the Faroes, there was a much more muted meteorological signature. This article is part of the themed issue ‘Atmospheric effects of solar eclipses stimulated by the 2015 UK eclipse’. PMID:27550769

  17. KOI-1003: A New Spotted, Eclipsing RS CVn Binary in the Kepler Field

    NASA Astrophysics Data System (ADS)

    Roettenbacher, Rachael M.; Kane, Stephen R.; Monnier, John D.; Harmon, Robert O.

    2016-12-01

    Using the high-precision photometry from the Kepler space telescope, thousands of stars with stellar and planetary companions have been observed. The characterization of stars with companions is not always straightforward and can be contaminated by systematic and stellar influences on the light curves. Here, through a detailed analysis of starspots and eclipses, we identify KOI-1003 as a new, active RS CVn star—the first identified with data from Kepler. The Kepler light curve of this close binary system exhibits the system’s primary transit, secondary eclipse, and starspot evolution of two persistent active longitudes. The near equality of the system’s orbital and rotation periods indicates the orbit and primary star’s rotation are nearly synchronized ({P}{orb}=8.360613+/- 0.000003 {days}; {P}{rot}˜ 8.23 {days}). By assuming the secondary star is on the main sequence, we suggest the system consists of a {1.45}-0.19+0.11 {M}⊙ subgiant primary and a {0.59}-0.04+0.03 {M}⊙ main-sequence companion. Our work gives a distance of 4400 ± 600 pc and an age of t={3.0}+2.0-0.5 {Gyr}, parameters which are discrepant with previous studies that included the star as a member of the open cluster NGC 6791.

  18. Gravity waves produced by the total solar eclipse of 1 August 2008

    NASA Astrophysics Data System (ADS)

    Marty, Julien; Francis, Dalaudier; Damien, Ponceau; Elisabeth, Blanc; Ulziibat, Munkhuu

    2010-05-01

    Gravity waves are a major component of atmospheric small scale dynamics because of their ability to transport energy and momentum over considerable distances and of their interactions with the mean circulation or other waves. They produce pressure variations which can be detected at the ground by microbarographs. The solar intensity reduction which occurs in the atmosphere during solar eclipses is known to act as a temporary source of large scale gravity waves. Despite decades of research, observational evidence for a characteristic bow-wave response of the atmosphere to eclipse passages remains elusive. A new versatile numerical model (Marty, J. and Dalaudier, F.: Linear spectral numerical model for internal gravity wave propagation. J. Atmos. Sci. (in press)) is presented and applied to the cooling of the atmosphere during a solar eclipse. Calculated solutions appear to be in good agreement with ground pressure fluctuations recorded during the total solar eclipse of 1 August 2008. To the knowledge of the authors, this is the first time that such a result is presented. A three-dimensional linear spectral numerical model is used to propagate internal gravity wave fluctuations in a stably stratified atmosphere. The model is developed to get first-order estimations of gravity wave fluctuations produced by identified sources. It is based on the solutions of the linearized fundamental fluid equations and uses the fully-compressible dispersion relation for inertia-gravity waves. The spectral implementation excludes situations involving spatial variations of buoyancy frequency or background wind. However density stratification variations are taken into account in the calculation of fluctuation amplitudes. In addition to gravity wave packet free propagation, the model handles both impulsive and continuous sources. It can account for spatial and temporal variations of the sources allowing to cover a broad range of physical situations. It is applied to the case of solar

  19. On the detection and attribution of gravity waves generated by the 20 March 2015 solar eclipse

    PubMed Central

    2016-01-01

    Internal gravity waves are generated as adjustment radiation whenever a sudden change in forcing causes the atmosphere to depart from its large-scale balanced state. Such a forcing anomaly occurs during a solar eclipse, when the Moon’s shadow cools part of the Earth’s surface. The resulting atmospheric gravity waves are associated with pressure and temperature perturbations, which in principle are detectable both at the surface and aloft. In this study, surface pressure and temperature data from two UK sites at Reading and Lerwick are examined for eclipse-driven gravity wave perturbations during the 20 March 2015 solar eclipse over northwest Europe. Radiosonde wind data from the same two sites are also analysed using a moving parcel analysis method, to determine the periodicities of the waves aloft. On this occasion, the perturbations both at the surface and aloft are found not to be confidently attributable to eclipse-driven gravity waves. We conclude that the complex synoptic weather conditions over the UK at the time of this particular eclipse helped to mask any eclipse-driven gravity waves. This article is part of the themed issue ‘Atmospheric effects of solar eclipses stimulated by the 2015 UK eclipse’. PMID:27550763

  20. Observations of Comets and Eclipses in the Andes

    NASA Astrophysics Data System (ADS)

    Ziółkowski, Mariusz

    There is no doubt that the Incas possessed a system for observing and interpreting unusual astronomical phenomena, such as eclipses or comets. References to it, however, are scarce, often of anecdotal nature and are not collected into any coherent "Inca observation catalog". The best documented of such events is the "Ataw Wallpa's comet", seen in Cajamarca in July of 1533 and the solar eclipse, that in 1543, prevented conquistador Lucas Martínez from discovering the rich silver mines in northern Chile. Archived descriptions of the Andean population's reaction to these phenomena indicate that they were treated as extremely important omens, that should not, under any circumstances, be ignored.