The colour-magnitude diagram of NGC 5053

International Nuclear Information System (INIS)

Walker, M.F.; Pike, C.D.; McGee, J.D.

1976-01-01

The colour-magnitude diagram of NGC 5053 has been derived to V = 21.1 from photographic and electronographic observations. The electronographic observations were obtained with an experimental Spectracon image-converter, having photocathode and exit window dimensions of 20 x 30 mm, mounted at the prime-focus of the 120-in. Lick reflector. The photographic observations were obtained with the 20-in. Carnegie astrograph and the 36-in. Crossley reflector. The colour-magnitude diagram resembles that of M92, with the difference that a red horizontal branch is more pronounced than the asymptotic branch in NGC 5053. The topology of the horizontal branch is that of clusters with an intermediate metal content and is thus at variance with the mean period of the RR Lyr stars and the unreddened colour of the subgiant branch read at the magnitude level of the horizontal branch, both of which would indicate an extremely low metal content. If comparison of the colour-magnitude diagrams of NGC 5053 and M92 is valid, then the reddening of NGC 5053 is Esub(B-V) = 0.02 and the apparent distance modulus is m-M = 16.08 +- 0.08. (author)

VizieR Online Data Catalog: Proper motions in M 11 (Su+ 1998)

Science.gov (United States)

Su, C.-G.; Zhao, J.-L.; Tian, K.-P.

1997-07-01

Relative proper motions of 872 stars in the open cluster M 11 region are reduced using 10 plate pairs taken over time baselines of 16~70 years with the double astrograph telescope of Shanghai Observatory. The scale is 30"/mm. The plates were measured with the PDS machines in the Purple Mountain Observatory in Nanjing and the Institute of Technology and Communication in Luoyang, China. The average proper motion accuracy is about 1.1mas/yr with 85% of the data better than 1mas/yr. Membership probabilities of 785 stars within 25' centred on M 11 are determined based on their proper motions. The method used is suggested by Su et al. (1995AcApS..15..217S) with some improvements of Zhao & He (1990A&A...237...54Z), in which the space distribution and magnitude dependencies for cluster stars are taken into account. The results are significantly good. The total integrated membership probabilities for all these stars is 547 and the number of stars with probabilities higher than 0.7 is 541. It can be found after the membership determination that there exists mass segregation in M 11. Some comparisons and discussion are also given. (1 data file).

Early German plans for southern observatories

Science.gov (United States)

Wolfschmidt, G.

2002-07-01

As early as the 18th and 19th centuries, French and English observers were active in South Africa. Around the beginning of the 20th century, Heidelberg and Potsdam astronomers proposed a southern observatory. Then Göttingen astronomers suggested building an observatory in Windhoek for photographing the sky and measuring the solar constant. In 1910 Karl Schwarzschild (1873-1916), after a visit to observatories in the United States, pointed out the usefulness of an observatory in South West Africa, in a climate superior to that in Germany, giving German astronomers access to the southern sky. Seeing tests were begun in 1910 by Potsdam astronomers, but WW I stopped the plans. In 1928 Erwin Finlay-Freundlich (1885-1964), inspired by the Hamburg astronomer Walter Baade (1893-1960), worked out a detailed plan for a southern observatory with a reflecting telescope, spectrographs and an astrograph with an objective prism. Paul Guthnick (1879-1947), director of the Berlin observatory, in cooperation with APO Potsdam and Hamburg, made a site survey to Africa in 1929 and found the conditions in Windhoek to be ideal. Observations were started in the 1930s by Berlin and Breslau astronomers, but were stopped by WW II. In the 1950s, astronomers from Hamburg and The Netherlands renewed the discussion in the framework of European cooperation, and this led to the founding of ESO in 1963.

UCAC3 PIXEL PROCESSING

International Nuclear Information System (INIS)

Zacharias, Norbert

2010-01-01

The third US Naval Observatory CCD Astrograph Catalog, UCAC3, was released at the IAU General Assembly on 2009 August 10. It is a highly accurate, all-sky astrometric catalog of about 100 million stars in the R = 8-16 mag range. Recent epoch observations are based on over 270,000 CCD exposures, which have been re-processed for the UCAC3 release applying traditional and new techniques. Challenges in the data have been high dark current and asymmetric image profiles due to the poor charge transfer efficiency of the detector. Non-Gaussian image profile functions were explored and correlations are found for profile fit parameters with properties of the CCD frames. These were utilized to constrain the image profile fit models and adequately describe the observed point-spread function of stellar images with a minimum number of free parameters. Using an appropriate model function, blended images of double stars could be fit successfully. UCAC3 positions are derived from two-dimensional image profile fits with a five-parameter, symmetric Lorentz profile model. Internal precisions of about 5 mas per coordinate and single exposure are found, which are degraded by the atmosphere to about 10 mas. However, systematic errors exceeding 100 mas are present in the x, y data which have been corrected in the astrometric reductions following the x, y data reduction step described here.

FON: From Start to Finish

Science.gov (United States)

Pakuliak, L. K.; Andruk, V. M.; Golovnia, V. V.; Shatokhina, S. V.; Yizhakevych, O. M.; Ivanov, G. A.; Yatsenko, A. I.; Sergeeva, T. P.

Almost 40-year history of FON project ended with the creation of the whole northern sky catalog of objects down to B ≤ 16.5m. The idea of 4-fold overlapping of the northern sky with 6 wide-field astrographs has not been realized in full. For historical reasons it has been transformed into the 2-fold overlapping observational program of MAO NAS of Ukraine, resulted in three versions of the multimillion catalog of positions, proper motions, and B-magnitudes of stars. The first version of 1.2 million stars had been finished before the 2000s and is based on the AC object list. The measurements of plates were made by automatic measuring complex PARSEC, specially developed for massive photographic reviews. As the input list was limited by AC objects, the most part of stars on the FON plates remained unmeasured. Principles of workflow organization of such works formed the basis for the further development of the project using the latest IT-technologies. For the creation of the second and the third versions of the catalog, the list of objects was obtained as a result of total digitizing of plates and their image processing. The final third version contains 19.5 million stars and galaxies with the maximum possible for the photographic astrometry accuracy. The collection of plates, obtained in other observatories - participants of the project, are partially safe and can be used for the same astrometric tasks.

An Investigation on the Use of Different Centroiding Algorithms and Star Catalogs in Astro-Geodetic Observations

Science.gov (United States)

Basoglu, Burak; Halicioglu, Kerem; Albayrak, Muge; Ulug, Rasit; Tevfik Ozludemir, M.; Deniz, Rasim

2017-04-01

In the last decade, the importance of high-precise geoid determination at local or national level has been pointed out by Turkish National Geodesy Commission. The Commission has also put objective of modernization of national height system of Turkey to the agenda. Meanwhile several projects have been realized in recent years. In Istanbul city, a GNSS/Levelling geoid was defined in 2005 for the metropolitan area of the city with an accuracy of ±3.5cm. In order to achieve a better accuracy in this area, "Local Geoid Determination with Integration of GNSS/Levelling and Astro-Geodetic Data" project has been conducted in Istanbul Technical University and Bogazici University KOERI since January 2016. The project is funded by The Scientific and Technological Research Council of Turkey. With the scope of the project, modernization studies of Digital Zenith Camera System are being carried on in terms of hardware components and software development. Accentuated subjects are the star catalogues, and centroiding algorithm used to identify the stars on the zenithal star field. During the test observations of Digital Zenith Camera System performed between 2013-2016, final results were calculated using the PSF method for star centroiding, and the second USNO CCD Astrograph Catalogue (UCAC2) for the reference star positions. This study aims to investigate the position accuracy of the star images by comparing different centroiding algorithms and available star catalogs used in astro-geodetic observations conducted with the digital zenith camera system.

Discovery of Japan’s Oldest Photographic Plates of a Starfield

Science.gov (United States)

Watanabe, Jun-ichi; Sasaki, Goro; Nakagiri, Masao; Ohshima, Norio

2015-08-01

The Public Outreach and Archive Office in NAOJ has been inspecting as many as 20,000 old photographic plates, which were found in a pile of cardboard cartons. In the course of their inspections, we have discovered 437 plates recorded from the end of the 19th century to the beginning of the 20th century. This was the first era in which observations were recorded using photographic plates in Japan.Most of the plates were obtained by using the Brashear astrograph at Azabubu in the 19th century. The oldest photographic plate was marked (delete ‘as’) No.13 and was recorded on March 5, 1899. We also found a number of historically important plates; among these are images of the first minor planet “TOKIO” that was detected in Japan and named after our country, and of a star 61 Cyg, with a large proper motion.We have long known that Tokyo Observatory of Tokyo Imperial University began its observations at Azabu. However, for many years, everyone believed that all the plates and observational instruments were lost in the chaos following the Great Kanto earthquake (1923) and in a fire that damaged Tokyo Observatory’s main building during the World War II, events that took place before and after the Observatory’s move to Mitaka. We made a catalogue of these plates and will present some statistics along with our effort for archives in our observatory.

A multimembership catalogue for 1876 open clusters using UCAC4 data

Science.gov (United States)

Sampedro, L.; Dias, W. S.; Alfaro, E. J.; Monteiro, H.; Molino, A.

2017-10-01

The main objective of this work is to determine the cluster members of 1876 open clusters, using positions and proper motions of the astrometric fourth United States Naval Observatory (USNO) CCD Astrograph Catalog (UCAC4). For this purpose, we apply three different methods, all based on a Bayesian approach, but with different formulations: a purely parametric method, another completely non-parametric algorithm and a third, recently developed by Sampedro & Alfaro, using both formulations at different steps of the whole process. The first and second statistical moments of the members' phase-space subspace, obtained after applying the three methods, are compared for every cluster. Although, on average, the three methods yield similar results, there are also specific differences between them, as well as for some particular clusters. The comparison with other published catalogues shows good agreement. We have also estimated, for the first time, the mean proper motion for a sample of 18 clusters. The results are organized in a single catalogue formed by two main files, one with the most relevant information for each cluster, partially including that in UCAC4, and the other showing the individual membership probabilities for each star in the cluster area. The final catalogue, with an interface design that enables an easy interaction with the user, is available in electronic format at the Stellar Systems Group (SSG-IAA) web site (http://ssg.iaa.es/en/content/sampedro-cluster-catalog).

Progressive Research and Outreach at the WestRock Observatory

Science.gov (United States)

Brown, Johnny Eugene; Lantz Caughey, Austin; O'Keeffe, Brendon; Johnson, Michael; Murphy Williams, Rosa Nina

2016-01-01

The WestRock Observatory (WRO), located in Columbus State University's Coca-Cola Space Science Center (CCSSC), is dedicated to education and research in astronomy through hands-on engagement and public participation. The WRO has recently received funding to upgrade the PlaneWave CDK 24-inch Corrected Dall-Kirkham Astrograph telescope. Recent additions to the telescope include an all-new Apogee Alta F16 CCD camera complete with a filter wheel (with narrowband and broadband filters) and a Minor Planet Center Observatory Code (W22). These new upgrades have allowed Astrophysics students to conduct unique research ranging from high precision minor planet astrometry, to broad- and narrow-band imaging of nebulae, to light curve analysis for variable star photometry. These new endeavours, in conjunction with an existing suite of Solar telescopes, gives the WRO the ability to live-stream solar and night-time observing. These streams are available both online and through interactive displays at the CCSSC making the WRO an educational outreach program for a worldwide public audience and a growing astronomical community.Current funding is allowing students to get even more research experience than previously attainable further enabling the expansion of our publicly available gallery of nebula and galaxy images. Support and funding for the acquirement,installation, and upgrading of the new PlaneWave CDK24 has been provided by the International Museum and Library Services via the Museums for America Award Additionally, individual NASA Space Grant Scholarships have helped to secure a number of student interns partially responsible for recent improvements.

CSU's MWV Observatory: A Facility for Research, Education and Outreach

Science.gov (United States)

Hood, John; Carpenter, N. D.; McCarty, C. B.; Samford, J. H.; Johnson, M.; Puckett, A. W.; Williams, R. N.; Cruzen, S. T.

2014-01-01

The Mead Westvaco Observatory (MWVO), located in Columbus State University's Coca-Cola Space Science Center, is dedicated to education and research in astronomy through hands-on engagement and public participation. The MWVO has recently received funding to upgrade from a 16-inch Meade LX-200 telescope to a PlaneWave CDK 24-inch Corrected Dall-Kirkham Astrograph telescope. This and other technological upgrades will allow this observatory to stream live webcasts for astronomical events, allowing a worldwide public audience to become a part of the growing astronomical community. This poster will explain the upgrades that are currently in progress as well as the results from the current calibrations. The goal of these upgrades is to provide facilities capable of both research-class projects and widespread use in education and public outreach. We will present our initial calibration and tests of the observatory equipment, as well as its use in webcasts of astronomical events, in solar observing through the use of specialized piggy-backed telescopes, and in research into such topics as asteroids, planetary and nebula imaging. We will describe a pilot research project on asteroid orbit refinement and light curves, to be carried out by Columbus State University students. We will also outline many of the K-12 educational and public outreach activities we have designed for these facilities. Support and funding for the acquisition and installation of the new PlaneWave CDK 24 has been provided by the International Museum and Library Services via the Museums for America Award.

Early German Plans for a Southern Observatory

Science.gov (United States)

Wolfschmidt, Gudrun

As early as the 18th and 19th centuries, French and English observers were active in South Africa. Around the beginning of the 20th century the Heidelberg astronomer Max Wolf (1863-1932) proposed a southern observatory. In 1907 Hermann Carl Vogel (1841-1907), director of the Astrophysical Observatory Potsdam, suggested a southern station in Spain. His ideas for building an observatory in Windhuk for photographing the sky and measuring the solar constant were taken over by the Göttingen astronomers. In 1910 Karl Schwarzschild (1873-1916), after having visited the observatories in America, pointed out the usefulness of an observatory in South West Africa, where it would have better weather than in Germany and also give access to the southern sky. Seeing tests were begun in 1910 by Potsdam astronomers, but WW I stopped the plans. In 1928 Erwin Finlay-Freundlich (1885-1964), inspired by the Hamburg astronomer Walter Baade (1893-1960), worked out a detailed plan for a southern observatory with a reflecting telescope, spectrographs and an astrograph with an objective prism. Paul Guthnick (1879-1947), director of the Berlin observatory, in cooperation with APO Potsdam and Hamburg, made a site survey to Africa in 1929 and found the conditions in Windhuk to be ideal. Observations were started in the 1930s by Berlin and Breslau astronomers, but were stopped by WW II. In the 1950s, astronomers from Hamburg and The Netherlands renewed the discussion in the framework of European cooperation, and this led to the founding of ESO in 1963, as is well described by Blaauw (1991). Blaauw, Adriaan: ESO's Early History. The European Southern Observatory from Concept to Reality. Garching bei München: ESO 1991.

UCAC3 PROPER MOTION SURVEY. II. DISCOVERY OF NEW PROPER MOTION STARS IN UCAC3 WITH 0.''40 yr–1 > μ ≥ 0.''18 yr–1 BETWEEN DECLINATIONS –47° and 00°

International Nuclear Information System (INIS)

Finch, Charlie T.; Zacharias, Norbert; Boyd, Mark R.; Henry, Todd J.; Hambly, Nigel C.

2012-01-01

We present 474 new proper motion stellar systems in the southern sky having no previously known components, with 0.''40 yr –1 >μ ≥ 0.''18 yr –1 between declinations –47° and 0°. In this second paper utilizing the U.S. Naval Observatory third CCD Astrograph Catalog (UCAC3) we complete our sweep of the southern sky for objects in the proper motion range targeted by this survey with R magnitudes ranging from 9.80 to 19.61. The new systems contribute a ∼16% increase in the number of new stellar systems for the same region of sky reported in previous SuperCOSMOS Research Consortium On Nearby Stars (RECONS) surveys. Among the newly discovered stellar systems are 16 multiples, plus an additional ten components that are new common proper motion companions to previously known objects. A comparison of UCAC3 proper motions to those from Hipparcos, Tycho-2, Southern Proper Motion, and SuperCOSMOS indicates that all proper motions are consistent to ∼10 mas yr –1 , with the exception of SuperCOSMOS. Distance estimates are derived for all stellar systems having SuperCOSMOS Sky Survey B J , R 59F , and I IVN plate magnitudes and Two Micron All Sky Survey (2MASS) infrared photometry. We find five new red dwarf systems estimated to be within 25 pc. These discoveries support results from previous proper motion surveys suggesting that more nearby stellar systems are to be found, particularly in the fainter, slower moving samples. In this second paper utilizing the UCAC3 we complete our sweep of the southern sky for objects in the proper motion range targeted by this survey with R magnitudes ranging from 9.80 to 19.61.

The Equatorial Coordinates and B-Magnitudes of the Stars in the Southern Hemisphere Zones Based on the Digitized Astronegatives of FON Project at the Ulugh Beg Astronomical Institute

Science.gov (United States)

Yuldoshev, Q. X.; Muminov, M. M.; Ehgamberdiev, Sh. A.; Usmanov, O. U.; Relke, H.; Protsyuk, Yu. I.; Kovylianska, O. E.; Protsyuk, S. V.; Andruk, V. N.

FON (Russian abbreviation of the Photographic Sky Survey) were carried out at 6 observatories. The Kitab Observatory (KO) of Ulugh Beg Astronomical Institute (UBAI) of the Uzbek Academy of Sciences (UzAS) was involved in this project from 1981 to 1996. For the observations the Double Astrograph of Zeiss (DAZ, D/F = 40/300, 69"/mm) was used. On the FON project about 2600 photographic plates were exposed. In October, 2015 digitization of these astroplates were started using EPSON Expression 10000XL flatbed scanner with the spatial resolution of 1200 dpi and completed in June, 2016. The first stage of the work is the processing of the 2000 photographic plates in zones of the southern hemisphere with the declination between 0 and -20 degrees. The 1704 plates have already been processed. The equatorial coordinates α, δ of stars and galaxies were determined in the system of the Tycho2 catalogue and the Bmagnitudes in the system of the photoelectric standards. UBAI UzAS, Tashkent (Uzbekistan), ASU, Andijan (Uzbekistan), WHO, Essen (Germany), RI NAO, Nikolaev (Ukraine), MAO NASU, Kyiv (Ukraine) have taken part in the processing of the digitized images. For the data reduction the MIDAS package and software, developed in the MAO NASU were used. Based on the results of the processing of the astronegatives in the sectors of right ascension from 0 hours to 24 hours and declination from - 20° to 0° the internal errors of the catalogue were estimated. The errors calculated for all stars are 0.17" and 0.18m respectively. For the stars brighter than 14 magnitude the errors are 0.08" and 0.07m for the equatorial coordinates and B-magnitudes respectively.

A radio/optical reference frame. 5: Additional source positions in the mid-latitude southern hemisphere

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Russell, J. L.; Reynolds, J. E.; Jauncey, D. L.; de Vegt, C.; Zacharias, N.; Ma, C.; Fey, A. L.; Johnston, K. J.; Hindsley, R.; Hughes, J. A.; Malin, D. F.; White, G. L.; Kawaguchi, N.; Takahashi, Y.

1994-01-01

We report new accurate radio position measurements for 30 sources, preliminary positions for two sources, improved radio postions for nine additional sources which had limited previous observations, and optical positions and optical-radio differences for six of the radio sources. The Very Long Baseline Interferometry (VLBI) observations are part of the continuing effort to establish a global radio reference frame of about 400 compact, flat spectrum sources, which are evenly distributed across the sky. The observations were made using Mark III data format in four separate sessions in 1988-89 with radio telescopes at Tidbinbilla, Australia, Kauai, USA, and Kashima, Japan. We observed a total of 54 sources, including ten calibrators and three which were undetected. The 32 new source positions bring the total number in the radio reference frame catalog to 319 (172 northern and 147 southern) and fill in the zone -25 deg greater than delta greater than -45 deg which, prior to this list, had the lowest source density. The VLBI positions have an average formal precision of less than 1 mas, although unknown radio structure effects of about 1-2 mas may be present. The six new optical postion measurements are part of the program to obtain positions of the optical counterparts of the radio reference frame source and to map accurately the optical on to the radio reference frames. The optical measurements were obtained from United States Naval Observatory (USNO) Black Birch astrograph plates and source plates from the AAT, and Kitt Peak National Observatory (KPNO) 4 m, and the European Southern Observatory (ESO) Schmidt. The optical positions have an average precision of 0.07 sec, mostly due to the zero point error when adjusted to the FK5 optical frame using the IRS catalog. To date we have measured optical positions for 46 sources.

Reduction of EAO Positional Observations Database

Science.gov (United States)

Nefedyev, Yuri; Andreev, Alexey; Demina, Natalya; Churkin, Konstantin

2016-07-01

There is a large data bank of positional observations of Solar System bodies at Engelhadt Astronomical Observatory (EAO). The positional observations include the major planets, except Jupiter. Modern technologies replace classical methods of observations in astronomy and in astrometry as well. At the same time many positional observations have been gathered at astronomical observatories. So taking into account that observations of the past epochs have presenteda great value for astronomy and as times goes by their importance is growing it is obvious that positional astrometry will not lose its practical importance. This was noted in B3 XXIV IAU resolution by the General Assembly. The results of reduction of solar system bodies observations were published mainly in Proceeding of EAO and Transactions of Kazan City Astronomical Observatory. Earlier there have been made about three thousand observations at EAO and Zelenchuk station with the Zeiss telescope (D=400mm, f=2000mm), AFR-18 (photo visual, D=200, f=2000), refractor (D=400mm, f=3450mm), Meniscus camera (D=340mm, f=1200mm), Schmidt camera (D=350mm, f=2000mm). The major planets except Pluto and Neptune were observed with a special cassette chamber equipped with a rotating disk which had an open sector to reduce the brightness of the planets. The dimension of the sector was chosen accordingto the brightness of the planets. The disk was placed in the centre of the astrograph's field. The stars' true brightness was preserved. A large number of catalogues were compiled by the end of the 20th century. We used Tycho-2 catalogue for reducing our observations. As it is known the catalogue Tycho-2 (Tycho-2 catalogue, 2000) includes 2539913 stars. The stars' proper motions given in the catalogue were obtained by comparing positions from Tycho-2 with positions from the Astrographic Catalogue. Therefore they are considered to be highly accurate. The accuracy of stellar positions in Tycho-2 is about 60 mas and the accuracy of

First results of the Test-Bed Telescopes (TBT) project: Cebreros telescope commissioning

Science.gov (United States)

Ocaña, Francisco; Ibarra, Aitor; Racero, Elena; Montero, Ángel; Doubek, Jirí; Ruiz, Vicente

2016-07-01

The TBT project is being developed under ESA's General Studies and Technology Programme (GSTP), and shall implement a test-bed for the validation of an autonomous optical observing system in a realistic scenario within the Space Situational Awareness (SSA) programme of the European Space Agency (ESA). The goal of the project is to provide two fully robotic telescopes, which will serve as prototypes for development of a future network. The system consists of two telescopes, one in Spain and the second one in the Southern Hemisphere. The telescope is a fast astrograph with a large Field of View (FoV) of 2.5 x 2.5 square-degrees and a plate scale of 2.2 arcsec/pixel. The tube is mounted on a fast direct-drive mount moving with speed up to 20 degrees per second. The focal plane hosts a 2-port 4K x 4K back-illuminated CCD with readout speeds up to 1MHz per port. All these characteristics ensure good survey performance for transients and fast moving objects. Detection software and hardware are optimised for the detection of NEOs and objects in high Earth orbits (objects moving from 0.1-40 arcsec/second). Nominal exposures are in the range from 2 to 30 seconds, depending on the observational strategy. Part of the validation scenario involves the scheduling concept integrated in the robotic operations for both sensors. Every night it takes all the input needed and prepares a schedule following predefined rules allocating tasks for the telescopes. Telescopes are managed by RTS2 control software, that performs the real-time scheduling of the observation and manages all the devices at the observatory.1 At the end of the night the observing systems report astrometric positions and photometry of the objects detected. The first telescope was installed in Cebreros Satellite Tracking Station in mid-2015. It is currently in the commissioning phase and we present here the first results of the telescope. We evaluate the site characteristics and the performance of the TBT Cebreros

The architecture of Hamburg-Bergedorf Observatory 1906 - 1912, compared with other observatories (German Title: Die Architektur der Hamburg-Bergedorfer Sternwarte 1906 - 1912 im Vergleich mit anderen Observatorien)

Science.gov (United States)

Müller, Peter

The foundation of the astrophysical observatories in Potsdam-Telegrafenberg in 1874, in Meudon near Paris in 1875 and in Mount Hamilton in California in 1875 resulted in a complete change of observatory architecture. Astrometry had become irrelevant; meridian halls, i.e. an exact north-south orientation, were no longer necessary. The location in the centre of a (university) town was disadvantageous, due to vibrations caused by traffic and artificial light at night. New principles were defined: considerable distance (from the city center), secluded and exposed position (on a mountain) and construction of pavilions: inside a park a pavilion was built for each instrument. Other observatories of this type are: Pic du Midi in the French Alps, built as from 1878 as the first permanent observatory in the high mountains; Nice, Mont Gros, (1879); Brussels, Uccle (1883); Edinburgh, Blackford Hill (1892); Heidelberg, Königstuhl (1896); Barcelona, Monte Tibidado (1902). The original Hamburg Observatory was a modest rectangular building near the Millernrtor; in 1833 it became a State institute. As from 1906 erection of a spacious complex in Bergedorf, 20 km northeast of the city center, took place. Except for the unavailable position on a mountain, this complex fulfilled all principles of a modern observatory: in a park pavilion architecture in an elegant neo-baroque style designed by Albert Erbe (architect of the new Hamburger Kunsthalle with cupola). At the Hamburg Observatory the domed structures were cleverly hierarchised leaving an open view to the south. At the beginning astrometry and astrophysics were equally important; there was still a meridian circle. Apart from that, the instruments were manifold: a large refractor 0.60 m (installed by Repsold/Hamburg, 9 m focal length) and a large reflector 1 m (Zeiss/Jena, 3m focal length). Both were the largest instruments of their kind in the German Empire. In addition, there was the Lippert Astrograph on an elegant polar

The Selection and Protection of Optical Astronomical Observing Sites in China

Science.gov (United States)

Wenjing, Jin; Bai, Jinming; Yao, Yongqiang

2015-03-01

Before 1950 there are two observatories, Shanghai and Purple Mountain Astronomical Observatories (SHAO and PMO), and two observing stations, Qingdao and Kunming stations in China. With the requirements of astronomical research, two observatories, Beijing and Shaanxi Astronomical Observatories (BAO and SXAO) and two artificial satellite stations, Urumqi and Changchun, were established about 1960. Based on the current management, now there are 4 observatories, SHAO, PMO, NAOC(National Astronomical Observatories), which was grouped from BAO, YNAO and 2 others, as well as XAO (Xinjiang Astronomical Observatory). The optical 1-2 m class telescopes are being operated at former four observatories. SXAO is changed as National Time Service Center. Because of city expansion as well as the traveling and economic developments, these observatories are suffered severe light pollution. For example, Zo Ce is located at the suburb of Shanghai city. A 40 cm double astrograph was installed in 1900 and a 1.56 m optical reflector have been operated since November 1987. In 1994 the seeing is better than 1 and the night sky brightness in V is about 19 mag/arcsec 2, stars fainter than 20 mag with CCD are visibles. In 2007 a large playground was built in Zô Cè area. The light pollution is severe gradually. The night sky brightness has been increased to 15.8 mag/arcsec 2. The other observatories have similar situation. New site surveys and found new stations to solve the problem. Except the solar and radio stations of each Astronomical Observatory, now there are 3 optical observing sites at PMO (Hong-He, Xu-Yi and Yaoan), 2 at SHAO (Zô Cè and Tian Huang Ping) and 2 at YNAO (Kunming and Gao-Mei-Gu) as well as 1 optical observing site at BAO (Xing-Long). The best observing site is Gao-Mei-Gu, which is selected as the optical observing site of YNAO and where atmospheric turbulence distribution is 0.11 near ground with heights from 6.5m to 2.7m during night. Sky brightness in B and V band

The VMC survey. XXVIII. Improved measurements of the proper motion of the Galactic globular cluster 47 Tucanae

Science.gov (United States)

Niederhofer, Florian; Cioni, Maria-Rosa L.; Rubele, Stefano; Schmidt, Thomas; Bekki, Kenji; de Grijs, Richard; Emerson, Jim; Ivanov, Valentin D.; Oliveira, Joana M.; Petr-Gotzens, Monika G.; Ripepi, Vincenzo; Sun, Ning-Chen; van Loon, Jacco Th.

2018-05-01

We use deep multi-epoch point-spread function (PSF) photometry taken with the Visible and Infrared Survey Telescope for Astronomy (VISTA) to measure and analyze the proper motions of stars within the Galactic globular cluster 47 Tucanae (47 Tuc, NGC 104). The observations are part of the ongoing near-infrared VISTA survey of the Magellanic Cloud system (VMC). The data analyzed in this study correspond to one VMC tile, which covers a total sky area of 1.77 deg2. Absolute proper motions with respect to 9070 background galaxies are calculated from a linear regression model applied to the positions of stars in 11 epochs in the Ks filter. The data extend over a total time baseline of about 17 months. We found an overall median proper motion of the stars within 47 Tuc of (μαcos(δ), μδ) = (+5.89 ± 0.02 (statistical) ± 0.13 (systematic), -2.14 ± 0.02 (statistical) ± 0.08 (systematic)) mas yr-1, based on the measurements of 35 000 individual sources between 5' and 42' from the cluster center. We compared our result to the proper motions from the newest US Naval Observatory CCD Astrograph Catalog (UCAC5), which includes data from the Gaia data release 1. Selecting cluster members ( 2700 stars), we found a median proper motion of (μαcos(δ), μδ) = (+5.30 ± 0.03 (statistical) ± 0.70 (systematic), -2.70 ± 0.03 (statistical) ± 0.70 (systematic)) mas yr-1. Comparing the results with measurements in the literature, we found that the values derived from the VMC data are consistent with the UCAC5 result, and are close to measurements obtained using the Hubble Space Telescope. We combined our proper motion results with radial velocity measurements from the literature and reconstructed the orbit of 47 Tuc, finding that the cluster is on an orbit with a low ellipticity and is confined within the inner 7.5 kpc of the Galaxy. We show that the use of an increased time baseline in combination with PSF-determined stellar centroids in crowded regions significantly improves

New nearby white dwarfs from Gaia DR1 TGAS and UCAC5/URAT

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Scholz, R.-D.; Meusinger, H.; Jahreiß, H.

2018-05-01

Aims: Using an accurate Tycho-Gaia Astrometric Solution (TGAS) 25 pc sample that is nearly complete for GK stars and selecting common proper motion (CPM) candidates from the 5th United States Naval Observatory CCD Astrograph Catalog (UCAC5), we search for new white dwarf (WD) companions around nearby stars with relatively small proper motions. Methods: To investigate known CPM systems in TGAS and to select CPM candidates in TGAS+UCAC5, we took into account the expected effect of orbital motion on the proper motion and proper motion catalogue errors. Colour-magnitude diagrams (CMDs) MJ /J - Ks and MG /G - J were used to verify CPM candidates from UCAC5. Assuming their common distance with a given TGAS star, we searched for candidates that occupied similar regions in the CMDs as the few known nearby WDs (four in TGAS) and WD companions (three in TGAS+UCAC5). The CPM candidates with colours and absolute magnitudes corresponding neither to the main sequence nor to the WD sequence were considered as doubtful or subdwarf candidates. Results: With a minimum proper motion of 60 mas yr-1, we selected three WD companion candidates; two of which are also confirmed by their significant parallaxes measured in URAT data, whereas the third may also be a chance alignment of a distant halo star with a nearby TGAS star that has an angular separation of about 465 arcsec. One additional nearby WD candidate was found from its URAT parallax and GJKs photometry. With HD 166435 B orbiting a well-known G1 star at ≈24.6 pc with a projected physical separation of ≈700 AU, we discovered one of the hottest WDs, classified by us as DA2.0 ± 0.2, in the solar neighbourhood. We also found TYC 3980-1081-1 B, a strong cool WD companion candidate around a recently identified new solar neighbour with a TGAS parallax corresponding to a distance of ≈8.3 pc and our photometric classification as ≈M2 dwarf. This raises the question of whether previous assumptions on the completeness of the WD

The Golosyiv plate archive digitisation

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Sergeeva, T. P.; Sergeev, A. V.; Pakuliak, L. K.; Yatsenko, A. I.

2007-08-01

The plate archive of the Main Astronomical Observatory of the National Academy of Sciences of Ukraine (Golosyiv, Kyiv) includes about 85 000 plates which have been taken in various observational projects during 1950-2005. Among them are about 25 000 of direct northern sky area plates and more than 600 000 plates containing stellar, planetary and active solar formations spectra. Direct plates have a limiting magnitude of 14.0-16.0 mag. Since 2002 we have been organising the storage, safeguarding, cataloguing and digitization of the plate archive. The very initial task was to create the automated system for detection of astronomical objects and phenomena, search of optical counterparts in the directions of gamma-ray bursts, research of long period, flare and other variable stars, search and rediscovery of asteroids, comets and other Solar System bodies to improve the elements of their orbits, informational support of CCD observations and space projects, etc. To provide higher efficiency of this work we have prepared computer readable catalogues and database for 250 000 direct wide field plates. Now the catalogues have been adapted to Wide Field Plate Database (WFPDB) format and integrated into this world database. The next step will be adaptation of our catalogues, database and images to standards of the IVOA. Some magnitude and positional accuracy estimations for Golosyiv archive plates have been done. The photometric characteristics of the images of NGC 6913 cluster stars on two plates of the Golosyiv's double wide angle astrograph have been determined. Very good conformity of the photometric characteristics obtained with external accuracies of 0.13 and 0.15 mag. has been found. The investigation of positional accuracy have been made with A3± format fixed bed scanner (Microtek ScanMaker 9800XL TMA). It shows that the scanner has non-detectable systematic errors on the X-axis, and errors of ± 15 μm on the Y-axis. The final positional errors are about ± 2 μm (�

Obituary: Julena Steinheider Duncombe, 1911-2003

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Seidelmann, P. Kenneth

2004-12-01

Julena Steinheider Duncombe died on 13 September 2003, just eight days before her 92nd birthday. Julena Steinheider was born September 21, 1911 on a farm in Dorchester, Nebraska and grew up in Goehner, Nebraska. Her parents were Frederick and Ella Beenders Steinheider, and she had four brothers. She began college at the age of 17 and graduated at 21 from Doane College in Crete, Nebraska with a major in mathematics and a minor in astronomy. She started teaching in a one-room schoolhouse, where, with assistance from her family, she started possibly the first school lunch program by fixing lunches on the schoolhouse stove to provide food for children who only had popcorn to eat. Then she taught in Minatare and Scotts Bluff, Nebraska, and in a Japanese Relocation Camp in Wyoming. In 1945 she moved to Washington DC to begin working at the US Naval Observatory (USNO). She was the first woman observer on the 6-inch transit circle. She worked as an observer and mathematician reducing and analyzing observations of the Sun, Moon, planets, and stars. At the Naval Observatory she met Raynor Duncombe and married him in Goehner, Nebraska, in January 1948. She resigned from the USNO in 1948 to go with her husband to Yale University. At Yale the Duncombes introduced punched card equipment into the Astronomy Department. Ray also took graduate classes and Julie worked on Astrographic Catalog reductions. Upon returning to USNO in 1950 she joined the Nautical Almanac Office. She supervised the punched card operated typewriter to produce tables of positions of celestial bodies for air and sea navigation. With Dorrit Hoffleit she directed the keypunching of over 150 star catalogs, approximating 1.5 million cards. Several thousand errata to the catalogs were discovered and corrected on the cards and tape versions of the catalogs. This activity was the basis for future stellar databases. From 1963 she was responsible for producing the tabular predictions and maps for solar and lunar

SN1987A's Twentieth Anniversary

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2007-02-01

Looking back at 20 Years of Observations of this Supernova with ESO telescopes The unique supernova SN 1987A has been a bonanza for astrophysicists. It provided several observational 'firsts,' like the detection of neutrinos from an exploding star, the observation of the progenitor star on archival photographic plates, the signatures of a non-spherical explosion, the direct observation of the radioactive elements produced during the blast, observation of the formation of dust in the supernova, as well as the detection of circumstellar and interstellar material. ESO PR Photo 08a/07 ESO PR Photo 08a/07 SN1987A in the Large Magellanic Cloud Today, it is exactly twenty years since the explosion of Supernova 1987A in the Large Magellanic Cloud was first observed, at a distance of 163,000 light-years. It was the first naked-eye supernova to be seen for 383 years. Few events in modern astronomy have met with such an enthusiastic response by the scientists and now, after 20 years, it continues to be an extremely exciting object that is further studied by astronomers around the world, in particular using ESO's telescopes. When the first signs of Supernova 1987A, the first supernova of the year 1987, were noticed early on 24 February of that year, it was clear that this would be an unusual event. It was discovered by naked-eye and on a panoramic photographic plate taken with a 10-inch astrograph on Las Campanas in Chile by Oscar Duhalde and Ian Shelton, respectively. A few hours earlier, still on 23 February, two large underground detectors - in Japan and the USA - had registered the passage of high-energy neutrinos. Since SN 1987A exploded in the Large Magellanic Cloud (LMC), it was only accessible to telescopes in the Southern Hemisphere, more particularly in Australia, South Africa, and South America. In Chile, ESO's observatory at La Silla with its armada of telescopes with sizes between 0.5 and 3.6-m, played an important role. ESO PR Photo 08c/07 ESO PR Photo 08c/07 The

Obituary: Frank K. Edmondson (1912-2008)

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Pilachowski, Catherine A.; Olson, Margaret K. Edmondson; Edmondson, Frank K., Jr.

2009-12-01

Observatory in Brooklyn, IN, (a gift from Dr. Goethe Link, a noted Indianapolis physician and avid amateur astronomer), established a graduate program in astronomy, and enlarged the Department of Astronomy from two faculty members to eight. In one of his favorite stories, Edmondson bet Professor Cogshall a chocolate ice cream cone that President Herman B Wells would fund a new position for the Department, knowing full well that Wells had already agreed. Frank retired from IU in 1983. When many asteroids were lost during World War II, Frank and his colleague James Cuffey established the Indiana University Asteroid Program. Frank is credited with determining the orbits of 119 asteroids from 7000 photographic plates taken with a 10" astrographic telescope at the Goethe Link Observatory. Frank selected names for each of these asteroids, honoring IU Presidents, prominent scholars, and important Hoosier and astronomical landmarks. Asteroid 4300 Marg Edmondson he named for his wife Margaret. During his years as a faculty member at Indiana University, Frank advised Dr. Alfred Kinsey on statistical techniques for his pioneering studies of human sexuality, and also shared with Kinsey an abiding interest in classical music. The music and the programs at the IU School of Music brought great joy to Frank over his career at IU. His memory for programs he had heard in the past was phenomenal. Frank is best known in Bloomington for his remarkable skill as an educator. He loved teaching. He taught elementary astronomy to literally thousands of students, often taking advantage of his knowledge of music to introduce astronomical topics with appropriate musical selections. His popular, award-winning, televised astronomy course was broadcast to students throughout the state and is widely remembered even today. Following in the tradition of IU's legendary President Herman B Wells, whom he greatly admired, Frank devoted his career to service. In 1957 Indiana University became one of the seven