CIRCULAR No. 197 (FEBRUARY 2019)
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Observing List
day month year Epoch 2000 local clock time: 23.98 Observing List for 23 7 2019 RA DEC alt az Constellation object mag A mag B Separation description hr min deg min 20 50 Andromeda Gamma Andromedae (*266) 2.3 5.5 9.8 yellow & blue green double star 2 3.9 42 19 28 69 Andromeda Pi Andromedae 4.4 8.6 35.9 bright white & faint blue 0 36.9 33 43 30 55 Andromeda STF 79 (Struve) 6 7 7.8 bluish pair 1 0.1 44 42 16 52 Andromeda 59 Andromedae 6.5 7 16.6 neat pair, both greenish blue 2 10.9 39 2 45 67 Andromeda NGC 7662 (The Blue Snowball) planetary nebula, fairly bright & slightly elongated 23 25.9 42 32.1 31 60 Andromeda M31 (Andromeda Galaxy) large sprial arm galaxy like the Milky Way 0 42.7 41 16 31 61 Andromeda M32 satellite galaxy of Andromeda Galaxy 0 42.7 40 52 32 60 Andromeda M110 (NGC205) satellite galaxy of Andromeda Galaxy 0 40.4 41 41 17 55 Andromeda NGC752 large open cluster of 60 stars 1 57.8 37 41 17 48 Andromeda NGC891 edge on galaxy, needle-like in appearance 2 22.6 42 21 45 69 Andromeda NGC7640 elongated galaxy with mottled halo 23 22.1 40 51 46 57 Andromeda NGC7686 open cluster of 20 stars 23 30.2 49 8 30 121 Aquarius 55 Aquarii, Zeta 4.3 4.5 2.1 close, elegant pair of yellow stars 22 28.8 0 -1 12 120 Aquarius 94 Aquarii 5.3 7.3 12.7 pale rose & emerald 23 19.1 -13 28 32 152 Aquarius M72 globular cluster 20 53.5 -12 32 31 151 Aquarius M73 Y-shaped asterism of 4 stars 20 59 -12 38 16 117 Aquarius NGC7606 Galaxy 23 19.1 -8 29 32 149 Aquarius NGC7009 Saturn Neb planetary nebula, large & bright pale green oval 21 4.2 -11 21.8 38 135 -
Homogeneous Spectroscopic Parameters for Bright Planet Host Stars from the Northern Hemisphere the Impact on Stellar and Planetary Mass (Research Note)
A&A 576, A94 (2015) Astronomy DOI: 10.1051/0004-6361/201425227 & c ESO 2015 Astrophysics Homogeneous spectroscopic parameters for bright planet host stars from the northern hemisphere The impact on stellar and planetary mass (Research Note) S. G. Sousa1,2,N.C.Santos1,2, A. Mortier1,3,M.Tsantaki1,2, V. Adibekyan1, E. Delgado Mena1,G.Israelian4,5, B. Rojas-Ayala1,andV.Neves6 1 Instituto de Astrofísica e Ciências do Espaço, Universidade do Porto, CAUP, Rua das Estrelas, 4150-762 Porto, Portugal e-mail: [email protected] 2 Departamento de Física e Astronomia, Faculdade de Ciências, Universidade do Porto, Rua do Campo Alegre, 4169-007 Porto, Portugal 3 SUPA, School of Physics and Astronomy, University of St Andrews, St Andrews KY16 9SS, UK 4 Instituto de Astrofísica de Canarias, 38200 La Laguna, Tenerife, Spain 5 Departamento de Astrofísica, Universidade de La Laguna, 38205 La Laguna, Tenerife, Spain 6 Departamento de Física, Universidade Federal do Rio Grande do Norte, Brazil Received 27 October 2014 / Accepted 19 February 2015 ABSTRACT Aims. In this work we derive new precise and homogeneous parameters for 37 stars with planets. For this purpose, we analyze high resolution spectra obtained by the NARVAL spectrograph for a sample composed of bright planet host stars in the northern hemisphere. The new parameters are included in the SWEET-Cat online catalogue. Methods. To ensure that the catalogue is homogeneous, we use our standard spectroscopic analysis procedure, ARES+MOOG, to derive effective temperatures, surface gravities, and metallicities. These spectroscopic stellar parameters are then used as input to compute the stellar mass and radius, which are fundamental for the derivation of the planetary mass and radius. -
Modelling the X-Ray Emission of the O3+O6 Binary HD 150136 Via a Wind-Star Collision
Mon. Not. R. Astron. Soc. 000, 1{5 (2013) Printed 8 November 2013 (MN LATEX style file v2.2) Modelling the X-ray emission of the O3+O6 binary HD 150136 via a wind-star collision C. M. P. Russell1?, A. T. Okazaki1, S. P. Owocki2, J.-C. Leyder3, A. M. T. Pollock3, and M. F. Corcoran4;5 1Faculty of Engineering, Hokkai-Gakuen University, Toyohira-ku, Sapporo 02-8605, Japan 2Department of Physics & Astronomy, University of Delaware, Newark, DE 19716, USA 3European Space Agency, European Space Astronomy Centre, P.O. Box 78, E-28691 Villanueva de la Can~ada, Spain 4NASA/GSFC, Greenbelt, MD 20771, USA 5Universities Space Research Association, Columbia, MD 21044, USA Accepted 2013 XXXX XX. Received 2013 XXXX XX; in original form 2013 November 07 ABSTRACT HD 150136 is a short-period (2.675 d), O3+O6 binary system harbouring the nearest O3 star. The literature wind parameters suggest that the stronger O3 primary wind will overwhelm the O6 secondary wind along the line between the stars and induce a `wind-star collision' (WSC). We use 3D smoothed particle hydrodynamics (SPH) to model this WSC, as well as the wind-wind collision (WWC) produced off-axis, to dis- cern the density and temperature structure of the shocked winds, and then perform 3D radiative transfer to compute the X-ray properties of the system. The model qualita- tively reproduces the Chandra X-ray light curve obtained around superior conjunction, and could reproduce this observation in absolute flux depending on the contribution of embedded-wind-shock X-rays. The model spectra match well in the soft band and show the same strong lines as the data, although the hard flux is underestimated. -
Manuscript (V6c)
Mon. Not. R. Astron. Soc. 000, 000–000 (0000) Printed 30 September 2009 (MN LATEX style file v2.2) Measuring mass-loss rates and constraining shock physics for ten OB stars using Chandra X-ray emission line profiles Emma E. Wollman,1 David H. Cohen,1 Maurice A. Leutenegger,2 Stanley P. Owocki,3 Janos Zsarg´o,4 D. John Hillier4 1Swarthmore College, Department of Physics and Astronomy, Swarthmore, Pennsylvania 19081, USA 2NASA/Goddard Space Flight Center, Laboratory for High Energy Astrophysics, Code 622, Greenbelt, Maryland 20771, USA 3University of Delaware, Bartol Research Institute, Newark, Delaware 19716, USA 4University of Pittsburgh, Department of Physics and Astronomy, 3941 O’Hara St., Pittsburgh, Pennsylvania 15260, USA 30 September 2009 ABSTRACT X-ray spectral lines provide a powerful diagnostic of massive star winds. An X-ray emission line’s characteristic shape is affected by the kinematics of the hot plasma where the X-rays are produced and by the properties of the attenuating bulk material of the wind, so X-rays can be used as a probe of both wind components. Qualitatively, X-ray lines in massive stars have been observed to lack the signatures of absorption that are predicted by other diagnostics. In this paper, following the methods of Cohen et al. (2009), we analyze the spectra of ten stars from the Chandra archive in order to 1) quantify the amount of absorption by determining mass-loss rates for all stars and 2) test predictions of the wind-shock X-ray production scenario by determining onset radii and terminal velocities for the X-ray producing material. -
Barium & Related Stars and Their White-Dwarf Companions II. Main
Astronomy & Astrophysics manuscript no. dBa_orbits c ESO 2019 April 9, 2019 Barium & related stars and their white-dwarf companions ?, ?? II. Main-sequence and subgiant stars A. Escorza1; 2, D. Karinkuzhi2; 3, A. Jorissen2, L. Siess2, H. Van Winckel1, D. Pourbaix2, C. Johnston1, B. Miszalski4; 5, G-M. Oomen1; 6, M. Abdul-Masih1, H.M.J. Boffin7, P. North8, R. Manick1; 4, S. Shetye2; 1, and J. Mikołajewska9 1 Institute of Astronomy, KU Leuven, Celestijnenlaan 200D, B-3001 Leuven, Belgium e-mail: [email protected] 2 Institut d’Astronomie et d’Astrophysique, Université Libre de Bruxelles, Boulevard du Triomphe, B-1050 Bruxelles, Belgium 3 Department of physics, Jnana Bharathi Campus, Bangalore University, Bangalore 560056, India 4 South African Astronomical Observatory, PO Box 9, Observatory 7935, South Africa 5 Southern African Large Telescope Foundation, PO Box 9, Observatory 7935, South Africa 6 Department of Astrophysics/IMAPP, Radboud University, P.O. Box 9010, 6500 GL Nijmegen, The Netherlands 7 ESO, Karl-Schwarzschild-str. 2, 85748 Garching bei München, Germany 8 Institut de Physique, Laboratoire d’astrophysique, École Polytechnique Fédérale de Lausanne (EPFL), Observatoire, 1290 Versoix, Switzerland 9 N. Copernicus Astronomical Center, Polish Academy of Sciences, Bartycka 18, 00-716 Warsaw, Poland Accepted ABSTRACT Barium (Ba) dwarfs and CH subgiants are the less-evolved analogues of Ba and CH giants. They are F- to G-type main-sequence stars polluted with heavy elements by a binary companion when the latter was on the Asymptotic Giant Branch (AGB). This companion is now a white dwarf that in most cases cannot be directly detected. We present a large systematic study of 60 objects classified as Ba dwarfs or CH subgiants. -
Wolf-Rayet Stars and O-Star Runaways with HIPPARCOS II. Photometry?
UvA-DARE (Digital Academic Repository) Wolf-Rayet stars and O-stars runaways with HIPPARCOS. II. Photometry Marchenko, S.V.; Moffat, A.F.J.; van der Hucht, K.A.; Seggewiss, W.; Schrijver, H.; Stenholm, B.; Lundstrom, I.; Setia Gunawan, D.Y.A.; Sutantyo, W.; van den Heuvel, E.P.J.; Cuyper, J.- P.; Gomez, A.E. Publication date 1998 Published in Astronomy & Astrophysics Link to publication Citation for published version (APA): Marchenko, S. V., Moffat, A. F. J., van der Hucht, K. A., Seggewiss, W., Schrijver, H., Stenholm, B., Lundstrom, I., Setia Gunawan, D. Y. A., Sutantyo, W., van den Heuvel, E. P. J., Cuyper, J-P., & Gomez, A. E. (1998). Wolf-Rayet stars and O-stars runaways with HIPPARCOS. II. Photometry. Astronomy & Astrophysics, 331, 1022-1036. General rights It is not permitted to download or to forward/distribute the text or part of it without the consent of the author(s) and/or copyright holder(s), other than for strictly personal, individual use, unless the work is under an open content license (like Creative Commons). Disclaimer/Complaints regulations If you believe that digital publication of certain material infringes any of your rights or (privacy) interests, please let the Library know, stating your reasons. In case of a legitimate complaint, the Library will make the material inaccessible and/or remove it from the website. Please Ask the Library: https://uba.uva.nl/en/contact, or a letter to: Library of the University of Amsterdam, Secretariat, Singel 425, 1012 WP Amsterdam, The Netherlands. You will be contacted as soon as possible. UvA-DARE is a service provided by the library of the University of Amsterdam (https://dare.uva.nl) Download date:30 Sep 2021 Astron. -
Observing List
day month year Epoch 2000 local clock time: 2.00 Observing List for 24 7 2019 RA DEC alt az Constellation object mag A mag B Separation description hr min deg min 39 64 Andromeda Gamma Andromedae (*266) 2.3 5.5 9.8 yellow & blue green double star 2 3.9 42 19 51 85 Andromeda Pi Andromedae 4.4 8.6 35.9 bright white & faint blue 0 36.9 33 43 51 66 Andromeda STF 79 (Struve) 6 7 7.8 bluish pair 1 0.1 44 42 36 67 Andromeda 59 Andromedae 6.5 7 16.6 neat pair, both greenish blue 2 10.9 39 2 67 77 Andromeda NGC 7662 (The Blue Snowball) planetary nebula, fairly bright & slightly elongated 23 25.9 42 32.1 53 73 Andromeda M31 (Andromeda Galaxy) large sprial arm galaxy like the Milky Way 0 42.7 41 16 53 74 Andromeda M32 satellite galaxy of Andromeda Galaxy 0 42.7 40 52 53 72 Andromeda M110 (NGC205) satellite galaxy of Andromeda Galaxy 0 40.4 41 41 38 70 Andromeda NGC752 large open cluster of 60 stars 1 57.8 37 41 36 62 Andromeda NGC891 edge on galaxy, needle-like in appearance 2 22.6 42 21 67 81 Andromeda NGC7640 elongated galaxy with mottled halo 23 22.1 40 51 66 60 Andromeda NGC7686 open cluster of 20 stars 23 30.2 49 8 46 155 Aquarius 55 Aquarii, Zeta 4.3 4.5 2.1 close, elegant pair of yellow stars 22 28.8 0 -1 29 147 Aquarius 94 Aquarii 5.3 7.3 12.7 pale rose & emerald 23 19.1 -13 28 21 143 Aquarius 107 Aquarii 5.7 6.7 6.6 yellow-white & bluish-white 23 46 -18 41 36 188 Aquarius M72 globular cluster 20 53.5 -12 32 36 187 Aquarius M73 Y-shaped asterism of 4 stars 20 59 -12 38 33 145 Aquarius NGC7606 Galaxy 23 19.1 -8 29 37 185 Aquarius NGC7009 -
December 2019 BRAS Newsletter
A Monthly Meeting December 11th at 7PM at HRPO (Monthly meetings are on 2nd Mondays, Highland Road Park Observatory). Annual Christmas Potluck, and election of officers. What's In This Issue? President’s Message Secretary's Summary Outreach Report Asteroid and Comet News Light Pollution Committee Report Globe at Night Member’s Corner – The Green Odyssey Messages from the HRPO Friday Night Lecture Series Science Academy Solar Viewing Stem Expansion Transit of Murcury Edge of Night Natural Sky Conference Observing Notes: Perseus – Rescuer Of Andromeda, or the Hero & Mythology Like this newsletter? See PAST ISSUES online back to 2009 Visit us on Facebook – Baton Rouge Astronomical Society Baton Rouge Astronomical Society Newsletter, Night Visions Page 2 of 25 December 2019 President’s Message I would like to thank everyone for having me as your president for the last two years . I hope you have enjoyed the past two year as much as I did. We had our first Members Only Observing Night (MOON) at HRPO on Sunday, 29 November,. New officers nominated for next year: Scott Cadwallader for President, Coy Wagoner for Vice- President, Thomas Halligan for Secretary, and Trey Anding for Treasurer. Of course, the nominations are still open. If you wish to be an officer or know of a fellow member who would make a good officer contact John Nagle, Merrill Hess, or Craig Brenden. We will hold our annual Baton Rouge “Gastronomical” Society Christmas holiday feast potluck and officer elections on Monday, December 9th at 7PM at HRPO. I look forward to seeing you all there. ALCon 2022 Bid Preparation and Planning Committee: We’ll meet again on December 14 at 3:00.pm at Coffee Call, 3132 College Dr F, Baton Rouge, LA 70808, UPCOMING BRAS MEETINGS: Light Pollution Committee - HRPO, Wednesday December 4th, 6:15 P.M. -
Density Estimation for Projected Exoplanet Quantities
Density Estimation for Projected Exoplanet Quantities Robert A. Brown Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 [email protected] ABSTRACT Exoplanet searches using radial velocity (RV) and microlensing (ML) produce samples of “projected” mass and orbital radius, respectively. We present a new method for estimating the probability density distribution (density) of the un- projected quantity from such samples. For a sample of n data values, the method involves solving n simultaneous linear equations to determine the weights of delta functions for the raw, unsmoothed density of the unprojected quantity that cause the associated cumulative distribution function (CDF) of the projected quantity to exactly reproduce the empirical CDF of the sample at the locations of the n data values. We smooth the raw density using nonparametric kernel density estimation with a normal kernel of bandwidth σ. We calibrate the dependence of σ on n by Monte Carlo experiments performed on samples drawn from a the- oretical density, in which the integrated square error is minimized. We scale this calibration to the ranges of real RV samples using the Normal Reference Rule. The resolution and amplitude accuracy of the estimated density improve with n. For typical RV and ML samples, we expect the fractional noise at the PDF peak to be approximately 80 n− log 2. For illustrations, we apply the new method to 67 RV values given a similar treatment by Jorissen et al. in 2001, and to the 308 RV values listed at exoplanets.org on 20 October 2010. In addition to an- alyzing observational results, our methods can be used to develop measurement arXiv:1011.3991v3 [astro-ph.IM] 21 Mar 2011 requirements—particularly on the minimum sample size n—for future programs, such as the microlensing survey of Earth-like exoplanets recommended by the Astro 2010 committee. -
PDF Hosted at the Radboud Repository of the Radboud University Nijmegen
PDF hosted at the Radboud Repository of the Radboud University Nijmegen The following full text is a publisher's version. For additional information about this publication click this link. http://hdl.handle.net/2066/205233 Please be advised that this information was generated on 2020-01-01 and may be subject to change. A&A 626, A128 (2019) Astronomy https://doi.org/10.1051/0004-6361/201935390 & c ESO 2019 Astrophysics Barium and related stars, and their white-dwarf companions II. Main-sequence and subgiant stars?,??,??? A. Escorza1,2, D. Karinkuzhi2,3, A. Jorissen2, L. Siess2, H. Van Winckel1, D. Pourbaix2, C. Johnston1, B. Miszalski4,5, G.-M. Oomen1,6, M. Abdul-Masih1, H. M. J. Boffin7, P. North8, R. Manick1,4, S. Shetye2,1, and J. Mikołajewska9 1 Institute of Astronomy, KU Leuven, Celestijnenlaan 200D, 3001 Leuven, Belgium e-mail: [email protected] 2 Institut d’Astronomie et d’Astrophysique, Université Libre de Bruxelles, Boulevard du Triomphe, 1050 Bruxelles, Belgium 3 Department of physics, Jnana Bharathi Campus, Bangalore University, Bangalore 560056, India 4 South African Astronomical Observatory, PO Box 9, Observatory 7935, South Africa 5 Southern African Large Telescope Foundation, PO Box 9, Observatory 7935, South Africa 6 Department of Astrophysics/IMAPP, Radboud University, PO Box 9010, 6500 GL Nijmegen, The Netherlands 7 ESO, Karl-Schwarzschild-str. 2, 85748 Garching bei München, Germany 8 Institut de Physique, Laboratoire d’astrophysique, École Polytechnique Fédérale de Lausanne (EPFL), Observatoire, 1290 Versoix, Switzerland 9 N. Copernicus Astronomical Center, Polish Academy of Sciences, Bartycka 18, 00-716 Warsaw, Poland Received 4 March 2019 / Accepted 5 April 2019 ABSTRACT Barium (Ba) dwarfs and CH subgiants are the less evolved analogues of Ba and CH giants. -
Where Are All the Sirius-Like Binary Systems?
Mon. Not. R. Astron. Soc. 000, 1-22 (2013) Printed 20/08/2013 (MAB WORD template V1.0) Where are all the Sirius-Like Binary Systems? 1* 2 3 4 4 J. B. Holberg , T. D. Oswalt , E. M. Sion , M. A. Barstow and M. R. Burleigh ¹ Lunar and Planetary Laboratory, Sonnett Space Sciences Bld., University of Arizona, Tucson, AZ 85721, USA 2 Florida Institute of Technology, Melbourne, FL. 32091, USA 3 Department of Astronomy and Astrophysics, Villanova University, 800 Lancaster Ave. Villanova University, Villanova, PA, 19085, USA 4 Department of Physics and Astronomy, University of Leicester, University Road, Leicester LE1 7RH, UK 1st September 2011 ABSTRACT Approximately 70% of the nearby white dwarfs appear to be single stars, with the remainder being members of binary or multiple star systems. The most numerous and most easily identifiable systems are those in which the main sequence companion is an M star, since even if the systems are unresolved the white dwarf either dominates or is at least competitive with the luminosity of the companion at optical wavelengths. Harder to identify are systems where the non-degenerate component has a spectral type earlier than M0 and the white dwarf becomes the less luminous component. Taking Sirius as the prototype, these latter systems are referred to here as ‘Sirius-Like’. There are currently 98 known Sirius-Like systems. Studies of the local white dwarf population within 20 pc indicate that approximately 8 per cent of all white dwarfs are members of Sirius-Like systems, yet beyond 20 pc the frequency of known Sirius-Like systems declines to between 1 and 2 per cent, indicating that many more of these systems remain to be found. -
Binocular Challenges
This page intentionally left blank Cosmic Challenge Listing more than 500 sky targets, both near and far, in 187 challenges, this observing guide will test novice astronomers and advanced veterans alike. Its unique mix of Solar System and deep-sky targets will have observers hunting for the Apollo lunar landing sites, searching for satellites orbiting the outermost planets, and exploring hundreds of star clusters, nebulae, distant galaxies, and quasars. Each target object is accompanied by a rating indicating how difficult the object is to find, an in-depth visual description, an illustration showing how the object realistically looks, and a detailed finder chart to help you find each challenge quickly and effectively. The guide introduces objects often overlooked in other observing guides and features targets visible in a variety of conditions, from the inner city to the dark countryside. Challenges are provided for viewing by the naked eye, through binoculars, to the largest backyard telescopes. Philip S. Harrington is the author of eight previous books for the amateur astronomer, including Touring the Universe through Binoculars, Star Ware, and Star Watch. He is also a contributing editor for Astronomy magazine, where he has authored the magazine’s monthly “Binocular Universe” column and “Phil Harrington’s Challenge Objects,” a quarterly online column on Astronomy.com. He is an Adjunct Professor at Dowling College and Suffolk County Community College, New York, where he teaches courses in stellar and planetary astronomy. Cosmic Challenge The Ultimate Observing List for Amateurs PHILIP S. HARRINGTON CAMBRIDGE UNIVERSITY PRESS Cambridge, New York, Melbourne, Madrid, Cape Town, Singapore, Sao˜ Paulo, Delhi, Dubai, Tokyo, Mexico City Cambridge University Press The Edinburgh Building, Cambridge CB2 8RU, UK Published in the United States of America by Cambridge University Press, New York www.cambridge.org Information on this title: www.cambridge.org/9780521899369 C P.