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A Basic Requirement for Studying the Heavens Is Determining Where In
Abasic requirement for studying the heavens is determining where in the sky things are. To specify sky positions, astronomers have developed several coordinate systems. Each uses a coordinate grid projected on to the celestial sphere, in analogy to the geographic coordinate system used on the surface of the Earth. The coordinate systems differ only in their choice of the fundamental plane, which divides the sky into two equal hemispheres along a great circle (the fundamental plane of the geographic system is the Earth's equator) . Each coordinate system is named for its choice of fundamental plane. The equatorial coordinate system is probably the most widely used celestial coordinate system. It is also the one most closely related to the geographic coordinate system, because they use the same fun damental plane and the same poles. The projection of the Earth's equator onto the celestial sphere is called the celestial equator. Similarly, projecting the geographic poles on to the celest ial sphere defines the north and south celestial poles. However, there is an important difference between the equatorial and geographic coordinate systems: the geographic system is fixed to the Earth; it rotates as the Earth does . The equatorial system is fixed to the stars, so it appears to rotate across the sky with the stars, but of course it's really the Earth rotating under the fixed sky. The latitudinal (latitude-like) angle of the equatorial system is called declination (Dec for short) . It measures the angle of an object above or below the celestial equator. The longitud inal angle is called the right ascension (RA for short). -
Unlocking Galactic Wolf-Rayet Stars with $\Textit {Gaia} $ DR2 II: Cluster
MNRAS 000,1{19 (2019) Preprint 7 May 2020 Compiled using MNRAS LATEX style file v3.0 Unlocking Galactic Wolf-Rayet stars with Gaia DR2 II: Cluster and Association membership Gemma Rate,? Paul A. Crowther, Richard J. Parkery Department of Physics and Astronomy, University of Sheffield, Sheffield, S3 7RH, UK Accepted XXX. Received YYY; in original form ZZZ ABSTRACT Galactic Wolf-Rayet (WR) star membership of star forming regions can be used to constrain the formation environments of massive stars. Here, we utilise Gaia DR2 parallaxes and proper motions to reconsider WR star membership of clusters and associations in the Galactic disk, supplemented by recent near-IR studies of young massive clusters. We find that only 18{36% of 553 WR stars external to the Galac- tic Centre region are located in clusters, OB associations or obscured star-forming regions, such that at least 64% of the known disk WR population are isolated, in contrast with only 13% of O stars from the Galactic O star Catalogue. The fraction located in clusters, OB associations or star-forming regions rises to 25{41% from a global census of 663 WR stars including the Galactic Centre region. We use simu- lations to explore the formation processes of isolated WR stars. Neither runaways, nor low mass clusters, are numerous enough to account for the low cluster member- ship fraction. Rapid cluster dissolution is excluded as mass segregation ensures WR stars remain in dense, well populated environments. Only low density environments consistently produce WR stars that appeared to be isolated during the WR phase. -
Spatial Distribution of Galactic Wolf-Rayet Stars and Implications for the Global Population
Mon. Not. R. Astron. Soc. 000, 1–43 (2014) Printed 8 October 2018 (MN LATEX style file v2.2) Spatial distribution of Galactic Wolf-Rayet stars and implications for the global population C. K. Rosslowe⋆ and P. A. Crowther Dept of Physics and Astronomy, University of Sheffield, Hicks Building, Hounsfield Road, S3 7RH, United Kingdom ABSTRACT We construct revised near-infrared absolute magnitude calibrations for 126 Galactic Wolf-Rayet (WR) stars at known distances, based in part upon recent large scale spectroscopic surveys. Application to 246 WR stars located in the field, permits us to map their Galactic distribution. As anticipated, WR stars generally lie in the thin disk (∼40 pc half width at half maximum) between Galactocentric radii 3.5–10 kpc, in accordance with other star formation tracers. We highlight 12 WR stars located at vertical distances of >300 pc from the midplane. Analysis of the radial variation in WR subtypes exposes a ubiquitously higher NWC /NWN ratio than predicted by stel- lar evolutionary models accounting for stellar rotation. Models for non-rotating stars or accounting for close binary evolution are more consistent with observations. We consolidate information acquired about the known WR content of the Milky Way to build a simple model of the complete population. We derive observable quantities over +300 a range of wavelengths, allowing us to estimate a total number of 1200−100 Galactic WR stars, implying an average duration of ∼ 0.25 Myr for the WR phase at the cur- rent Milky Way star formation rate. Of relevance to future spectroscopic surveys, we use this model WR population to predict follow-up spectroscopy to KS ≃ 13 mag will be necessary to identify 95% of Galactic WR stars. -
5-6Index 6 MB
CLEAR SKIES OBSERVING GUIDES 5-6" Carbon Stars 228 Open Clusters 751 Globular Clusters 161 Nebulae 199 Dark Nebulae 139 Planetary Nebulae 105 Supernova Remnants 10 Galaxies 693 Asterisms 65 Other 4 Clear Skies Observing Guides - ©V.A. van Wulfen - clearskies.eu - [email protected] Index ANDROMEDA - the Princess ST Andromedae And CS SU Andromedae And CS VX Andromedae And CS AQ Andromedae And CS CGCS135 And CS UY Andromedae And CS NGC7686 And OC Alessi 22 And OC NGC752 And OC NGC956 And OC NGC7662 - "Blue Snowball Nebula" And PN NGC7640 And Gx NGC404 - "Mirach's Ghost" And Gx NGC891 - "Silver Sliver Galaxy" And Gx Messier 31 (NGC224) - "Andromeda Galaxy" And Gx Messier 32 (NGC221) And Gx Messier 110 (NGC205) And Gx "Golf Putter" And Ast ANTLIA - the Air Pump AB Antliae Ant CS U Antliae Ant CS Turner 5 Ant OC ESO435-09 Ant OC NGC2997 Ant Gx NGC3001 Ant Gx NGC3038 Ant Gx NGC3175 Ant Gx NGC3223 Ant Gx NGC3250 Ant Gx NGC3258 Ant Gx NGC3268 Ant Gx NGC3271 Ant Gx NGC3275 Ant Gx NGC3281 Ant Gx Streicher 8 - "Parabola" Ant Ast APUS - the Bird of Paradise U Apodis Aps CS IC4499 Aps GC NGC6101 Aps GC Henize 2-105 Aps PN Henize 2-131 Aps PN AQUARIUS - the Water Bearer Messier 72 (NGC6981) Aqr GC Messier 2 (NGC7089) Aqr GC NGC7492 Aqr GC NGC7009 - "Saturn Nebula" Aqr PN NGC7293 - "Helix Nebula" Aqr PN NGC7184 Aqr Gx NGC7377 Aqr Gx NGC7392 Aqr Gx NGC7585 (Arp 223) Aqr Gx NGC7606 Aqr Gx NGC7721 Aqr Gx NGC7727 (Arp 222) Aqr Gx NGC7723 Aqr Gx Messier 73 (NGC6994) Aqr Ast 14 Aquarii Group Aqr Ast 5-6" V2.4 Clear Skies Observing Guides - ©V.A. -
Radio Sources in Low-Luminosity Active Galactic Nuclei
A&A 435, 521–543 (2005) Astronomy DOI: 10.1051/0004-6361:20042277 & c ESO 2005 Astrophysics Radio sources in low-luminosity active galactic nuclei IV. Radio luminosity function, importance of jet power, and radio properties of the complete Palomar sample N. M. Nagar1,2, H. Falcke3, and A. S. Wilson4 1 Kapteyn Institute, Landleven 12, 9747 AD Groningen, The Netherlands 2 Astronomy Group, Departamento de Física, Universidad de Concepción, Casilla 160-C, Concepción, Chile e-mail: [email protected] 3 ASTRON, PO Box 2, 7990 AA Dwingeloo, The Netherlands Department of Astronomy, Radboud University Nijmegen, Postbus 9010, 6500 GL Nijmegen, The Netherlands e-mail: [email protected] 4 Department of Astronomy, University of Maryland, College Park, MD 20742, USA Adjunct Astronomer, Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218, USA e-mail: [email protected] Received 29 October 2004 / Accepted 5 February 2005 Abstract. We present the completed results of a high resolution radio imaging survey of all (∼200) low-luminosity active galactic nuclei (LLAGNs) and AGNs in the Palomar Spectroscopic Sample of all (∼488) bright northern galaxies. The high incidences of pc-scale radio nuclei, with implied brightness temperatures ∼>107 K, and sub-parsec jets argue for accreting black holes in ∼>50% of all LINERs and low-luminosity Seyferts; there is no evidence against all LLAGNs being mini-AGNs. The detected parsec-scale radio nuclei are preferentially found in massive ellipticals and in type 1 nuclei (i.e. nuclei with broad Hα emission). The radio luminosity function (RLF) of Palomar Sample LLAGNs and AGNs extends three orders of magnitude below, and is continuous with, that of “classical” AGNs. -
Alexei V. Filippenko PUBLICATIONS (∗ = Refereed Journals); 18 July 2021
Alexei V. Filippenko PUBLICATIONS (∗ = refereed journals); 18 July 2021 Citations: >128k (ADS), >168k (Google Scholar). h-index: 150 (ADS), 172 (Google Scholar) ∗1) A. V. Filippenko and R. S. Simon (1981). Astron. Jour., 86, 671{686. \A Study of 52 RR Lyrae Stars in M15." ∗2) A. V. Filippenko (1982). Publ. Astron. Soc. Pacific, 94, 715{721. \The Importance of Atmospheric Differential Refraction in Spectrophotometry." ∗3) A. V. Filippenko and V. Radhakrishnan (1982). Astrophys. Jour., 263, 828{834. \Pulsar Nulling and Drifting Subpulse Phase Memory." 4) A. V. Filippenko, A. C. S. Readhead, and M. S. Ewing (1983). In Positron-Electron Pairs in Astrophysics (Proceedings of AIP Conference 101), ed. M. L. Burns, A. K. Harding, and R. Ramaty (New York: American Institute of Physics), 113{117. \The Effect of Nulls on the Drifting Subpulses in PSR 0809+74." ∗5) M. A. Malkan and A. V. Filippenko (1983). Astrophys. Jour., 275, 477{492. \The Stellar and Nonstellar Continua of Seyfert Galaxies: Nonthermal Emission in the Near-Infrared." ∗6) A. V. Filippenko and J. L. Greenstein (1984). Publ. Astron. Soc. Pacific, 96, 530{536. \Faint Spectrophotometric Standard Stars for Large Optical Telescopes. I." ∗7) A. V. Filippenko and J. P. Halpern (1984). Astrophys. Jour., 285, 458{474. \NGC 7213: A Key to the Nature of Liners?" ∗8) J. P. Halpern and A. V. Filippenko (1984). Astrophys. Jour., 285, 475{482. \The Nonstellar Continuum of the Seyfert Galaxy NGC 7213." 9) A. V. Filippenko (1984). Ph.D. thesis, California Institute of Technology. (Ann Arbor: University Microfilms International), \Physical Conditions in Low-Luminosity Active Galactic Nuclei." ∗10) A. -
219Th Meeting of the American Astronomical Society
219TH MEETING OF THE AMERICAN ASTRONOMICAL SOCIETY 8-12 JANUARY 2012 AUSTIN, TX All scientific sessions will be held at the: Austin Convention Center COUNCIL .......................... 2 500 East Cesar Chavez Street Austin, TX 78701-4121 EXHIBITORS ..................... 4 AAS Paper Sorters ATTENDEE SERVICES .......................... 9 Tom Armstrong, Blaise Canzian, Thayne Curry, Shantanu Desai, Aaron Evans, Nimish P. Hathi, SCHEDULE .....................15 Jason Jackiewicz, Sebastien Lepine, Kevin Marvel, Karen Masters, J. Allyn Smith, Joseph Tenn, SATURDAY .....................25 Stephen C. Unwin, Gerritt Vershuur, Joseph C. Weingartner, Lee Anne Willson SUNDAY..........................28 Session Numbering Key MONDAY ........................36 90s Sunday TUESDAY ........................91 100s Monday WEDNESDAY .............. 146 200s Tuesday 300s Wednesday THURSDAY .................. 199 400s Thursday AUTHOR INDEX ........ 251 Sessions are numbered in the Program Book by day and time. Please note, posters are only up for the day listed. Changes after 7 December 2011 are only included in the online program materials. 1 AAS Officers & Councilors President (6/2010-6/2013) Debra Elmegreen Vassar College Vice President (6/2009-6/2012) Lee Anne Willson Iowa State Univ. Vice President (6/2010-6/2013) Nicholas B. Suntzeff Texas A&M Univ. Vice President (6/2011-6/2014) Edward B. Churchwell Univ. of Wisconsin Secretary (6/2010-6/2013) G. Fritz Benedict Univ. of Texas, Austin Treasurer (6/2008-6/2014) Hervey (Peter) Stockman STScI Education Officer (6/2006-6/2012) Timothy F. Slater Univ. of Wyoming Publications Board Chair (6/2011-6/2015) Anne P. Cowley Arizona State Univ. Executive Officer (6/2006-Present) Kevin Marvel AAS Councilors Richard G. French Wellesley College (6/2009-6/2012) James D. -
Kinematic Disturbances in Optical Rotation Curves Among 89 Virgo
KINEMATIC DISTURBANCES IN OPTICAL ROTATION CURVES AMONG 89 VIRGO DISK GALAXIES Vera C. Rubin1,2 Department of Terrestrial Magnetism, Carnegie Institution of Washington 5241 Broad Branch Road N.W., Washington, D.C. 20015 [email protected] Andrew H. Waterman3 Montgomery Blair High School, Silver Spring, MD and Jeffrey D. P. Kenney1,2 Astronomy Department, P.O. Box 208101, Yale University, New Haven, CT. 06520 Received ; accepted arXiv:astro-ph/9904050v1 3 Apr 1999 1Visiting Astronomer, Kitt Peak National Observatory, which is operated by AURA, Inc. under contract to the National Science Foundation. 2Observations at Palomar Observatory were made as part of a collaborative agreement between the California Institute of Technology and the Carnegie Institution of Washington. 3present address: Stanford University, Stanford, CA. –2– ABSTRACT For 89 galaxies, mostly spirals, in the Virgo cluster region, we have obtained optical long-slit major axis spectra of the ionized gas. We find: (1) One-half of the Virgo galaxies we observed have regular rotation patterns, while the other 50% exhibit kinematic disturbances ranging from mild to major. Velocity complexities are generally consistent with those resulting from tidal encounters or accretion events. Since kinematic disturbances are expected to fade within ∼109 years, many Virgo galaxies have experienced several significant kinematic disturbances during their lifetimes. (2) There is no strong correlation of rotation curve complexity with Hubble type, with galaxy luminosity, with local galaxy density, or with HI deficiency. (3) A few Virgo galaxies have ionized gas of limited extent, with velocities exceptionally low for their luminosities. In these galaxies the gas must be not rotationally supported. -
On the M-Σ Relationship and SMBH Mass Estimates of Selected Nearby Galaxies
International Journal of Astronomy and Astrophysics, 2013, 3, 1-9 http://dx.doi.org/10.4236/ijaa.2013.33A001 Published Online July 2013 (http://www.scirp.org/journal/ijaa) On the M-σ Relationship and SMBH Mass Estimates of Selected Nearby Galaxies Alper K. Ateş, Can Battal Kılınç, Cafer İbanoğlu Astronomy and Space Sciences Department, Ege University, İzmir, Turkey Email: [email protected] Received March 11, 2013; revised April 13, 2013; accepted April 20, 2013 Copyright © 2013 Alper K. Ateş et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. ABSTRACT Super massive black holes are believed to influence galactic evolution and dynamics. A histogram of SMBH masses for different redshift regimes may reveal clues on how the SMBH evolve in time. A prominent method for SMBH mass estimation is based on the linear correlation between the bulge velocity dispersion and the SMBH mass. Known as M-σ relationship, this method is known to provide reasonable but not very accurate mass estimates due to considerable scat- ter in data. In order to increase the precision, we surveyed the literature and gathered SMBH and velocity dispersion data for low redshift (z < 0.02) spiral galaxies. We report the M-σ relationship for low redshift spiral galaxies as, M BH log 8.10 0.16 2.67 0.66 log 1 M Sun 200 km s By using this refined M-σ relationship we measured 32 SMBH masses and determined upper and lower mass bounda- ries and the mass histogram for spiral galaxies in a narrow redshift regime (0.016 < z < 0.017). -
Revised Shapley Ames.Pdf
A REVISED SHAPLEY-AMES CATALOG OF BRIGHT GALAXIES The Las Canspanas ridge iii Chile during the last stages of construction of the dome for the du Pont 2.5-meter reflector. The du Pout instrument is at the north end of'thr long escarpment. The Swope 1-meter reflector is in the left foreground. Photu courtesy oi'R, J. Bruuito ; 1*<7*J-. A Revised Shapley-Ames Catalog of Bright Galaxies Containing Data on Magnitudes, Types, and Redshifts for Galaxies in the Original Harvard Survey, Updated to Summer 1980. Also Contains a Selection of Photographs Illustrating the Luminosity Classification and a List of Additional Galaxies that Satisfy the Magnitude Limit of the Original Catalog. Allan Sandage and G. A. Tammann CARNEGIE INSTITUTION OF WASHINGTON PUBLICATION 635 WASHINGTON, D.C. • 198 1 ISBN:0-87U79-<i52-:i Libran oi'CongrrssCatalog Card No. 80-6H146 (JompoMtion. Printing, and Binding by Mmden-Stinehour. Inr. ('<»p\ritiht C ]'M\, (Jariit'^it* Institution nf Washington ACKNOWLEDGMENTS We are indebted to Miss B. Flach and Mrs. R. C. Kraan- Korteweg for their help in compiling part of the data. We also owe special thanks to Basil Katem for his large effort in de- termining revised coordinates by measurement of National Geo- graphic-Palomar Sky Survey prints and Uppsala Schmidt plates for most of the listed galaxies, and to John Bedke for his skill in reproducing the photographs. We are especially grateful to R. J. Brucato for his important help in obtaining the most recent plates at Las Campanas. We greatly appreciate the help of several observers for provid- ing prepublication redshift data. -
The Printable Telescope Observing Olympics Check List In
Stellafane: Visual Observing Olympics - 2018 “The Hidden Gems of Stellafane” Observe – Any 15 Objects in Any Telescope – Receive a Pin Name: 2nd Name Coordinates J2000 Type Const. Mag. Size □NGC5894 MCG 10-22-4 15 11 41.0 + 59 48 32 Gal. Dra 12.8 3.0’ x 0.4’ □NGC6217 Arp 185 16 32 39.4 + 78 11 54 Gal. UMi 11.9 2.6’ x 2.1’ □Vesta 4 Vesta 〜17 25 35.7 – 23 17 33 Ast Oph 6.5 Stellar □NGC6535 18 03 51.0 – 00 17 51 G.C. Ser 9.3 3.4’ x 3.4’ □NGC6539 18 04 50.0 – 07 35 10 G.C. Ser 8.9 7.9’ x 7.9’ □Barnard 92 LDN 323 18 15 27.9 – 18 13 19 Neb. Sgr -- 15.0’ x 9.0’ □Berkeley 82 19 11 20.3 + 13 06 49 O.C. Aql -- 4.0’ x 4.0’ □NGC6791 Berkeley 46 19 20 53.7 + 37 46 09 O.C. Lyr 9.5 10.0’ x 10.0’ □NGC6857 Sh2-100 20 01 48.7 + 33 31 32 Neb. Cyg 11.4 38” x 38” □Roslund 4 IC 4954 20 04 50.4 + 29 12 38 O.C. Vul 10.0 6.0’ x 6.0’ □NGC6888 Crescent Neb 20 12 01.0 + 38 23 00 Neb. Cyg -- 18.0’ x 8.0’ □IC4996 Cr 418 20 16 32.0 + 37 38 40 O.C. Cyg 7.3 5.0’ x 5.0’ □NGC6934 20 34 11.6 + 07 24 15 G.C. -
Inspec Vendor
ASTRONOMICAL CATALOGUE DESIGNATIONS This list of astronomical catalogue designations is designed to help in the online search for individual astronomical objects. All the major historical compilations and currently used catalogues that are most likely to be encountered in the literature have been included. The designations to be used are described by one typical example, a short description of the objects contained in that catalogue including an indication of the origin of the designation, format information, and where running numbers are involved (e.g. NN), the largest number likely to be encountered in that specific catalogue (e.g. 28). The lead-ins in italics reflect the complex alternative designations found in the literature. The ‘Systematic designations’ can also be used to construct a designation if one has not already been assigned. Some attempts have therefore been made to control the use of certain designations and this reflects the activities of the Working Group for Information Retrieval of Commission 5 of the International Astronomical Union. The catalogue information is based on the Second Reference Dictionary of the Nomenclature of Celestial Objects by Lortet et al. (Publication Speciale du C.D.S., No 24, Volumes I and II 1994) and the SIMBAD database. The “format” concept is an extension of the scheme devised by Mike Kesteven and Alan Bridle in February 1977 (J. Royal Astron. Soc. Canada, Vol. 71, p.21-39). Con Constellation (IAU 3-letter code) N Ordinal number (no positional information) F Field or plate number (no positional information) T Target (letters) HH Hours of right ascension MM.m Minutes of right ascension or declination SS.s Seconds of right ascension or declination (or seconds of time) DD.d Degrees in declination LLL.ll Degrees of Galactic longitude BB.bb Degrees of Galactic latitude R Roman numerals (I, II, III, IV, etc.) A, a, s Letters, subdivisions or suffixes YYMMDD Date (truncated year, month, day) YYYY Year VV Velocity (km/s) Coordinate-type formats use letter combinations, e.g.