Boletim Brasileiro De Astronomia
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Naming the Extrasolar Planets
Naming the extrasolar planets W. Lyra Max Planck Institute for Astronomy, K¨onigstuhl 17, 69177, Heidelberg, Germany [email protected] Abstract and OGLE-TR-182 b, which does not help educators convey the message that these planets are quite similar to Jupiter. Extrasolar planets are not named and are referred to only In stark contrast, the sentence“planet Apollo is a gas giant by their assigned scientific designation. The reason given like Jupiter” is heavily - yet invisibly - coated with Coper- by the IAU to not name the planets is that it is consid- nicanism. ered impractical as planets are expected to be common. I One reason given by the IAU for not considering naming advance some reasons as to why this logic is flawed, and sug- the extrasolar planets is that it is a task deemed impractical. gest names for the 403 extrasolar planet candidates known One source is quoted as having said “if planets are found to as of Oct 2009. The names follow a scheme of association occur very frequently in the Universe, a system of individual with the constellation that the host star pertains to, and names for planets might well rapidly be found equally im- therefore are mostly drawn from Roman-Greek mythology. practicable as it is for stars, as planet discoveries progress.” Other mythologies may also be used given that a suitable 1. This leads to a second argument. It is indeed impractical association is established. to name all stars. But some stars are named nonetheless. In fact, all other classes of astronomical bodies are named. -
The Minor Planet Bulletin
THE MINOR PLANET BULLETIN OF THE MINOR PLANETS SECTION OF THE BULLETIN ASSOCIATION OF LUNAR AND PLANETARY OBSERVERS VOLUME 36, NUMBER 3, A.D. 2009 JULY-SEPTEMBER 77. PHOTOMETRIC MEASUREMENTS OF 343 OSTARA Our data can be obtained from http://www.uwec.edu/physics/ AND OTHER ASTEROIDS AT HOBBS OBSERVATORY asteroid/. Lyle Ford, George Stecher, Kayla Lorenzen, and Cole Cook Acknowledgements Department of Physics and Astronomy University of Wisconsin-Eau Claire We thank the Theodore Dunham Fund for Astrophysics, the Eau Claire, WI 54702-4004 National Science Foundation (award number 0519006), the [email protected] University of Wisconsin-Eau Claire Office of Research and Sponsored Programs, and the University of Wisconsin-Eau Claire (Received: 2009 Feb 11) Blugold Fellow and McNair programs for financial support. References We observed 343 Ostara on 2008 October 4 and obtained R and V standard magnitudes. The period was Binzel, R.P. (1987). “A Photoelectric Survey of 130 Asteroids”, found to be significantly greater than the previously Icarus 72, 135-208. reported value of 6.42 hours. Measurements of 2660 Wasserman and (17010) 1999 CQ72 made on 2008 Stecher, G.J., Ford, L.A., and Elbert, J.D. (1999). “Equipping a March 25 are also reported. 0.6 Meter Alt-Azimuth Telescope for Photometry”, IAPPP Comm, 76, 68-74. We made R band and V band photometric measurements of 343 Warner, B.D. (2006). A Practical Guide to Lightcurve Photometry Ostara on 2008 October 4 using the 0.6 m “Air Force” Telescope and Analysis. Springer, New York, NY. located at Hobbs Observatory (MPC code 750) near Fall Creek, Wisconsin. -
On the Habitability of Our Universe
Chapter for the book Consolidation of Fine Tuning On the Habitability of Our Universe Abraham Loeb Astronomy department, Harvard University, 60 Garden Street, Cambridge, MA 02138, USA E-mail: [email protected] Abstract. Is life most likely to emerge at the present cosmic time near a star like the Sun? We consider the habitability of the Universe throughout cosmic history, and conservatively restrict our attention to the context of “life as we know it” and the standard cosmological model, ΛCDM. The habitable cosmic epoch started shortly after the first stars formed, about 30 Myr after the Big Bang, and will end about 10 Tyr from now, when all stars will die. We review the formation history of habitable planets and find that unless habitability around low mass stars is suppressed, life is most likely to exist near ∼ 0.1M stars ten trillion years from now. Spectroscopic searches for biosignatures in the atmospheres of transiting Earth-mass planets around low mass stars will determine whether present-day life is indeed premature or typical from a cosmic perspective. arXiv:1606.08926v2 [astro-ph.CO] 24 Nov 2016 Contents 1 Introduction2 2 The Habitable Epoch of the Early Universe4 2.1 Section Background4 2.2 First Planets4 2.3 Section Summary and Implications5 3 CEMP Stars: Possible Hosts to Carbon Planets in the Early Universe6 3.1 Section Background6 3.2 Star-forming environment of CEMP stars7 3.3 Orbital Radii of Potential Carbon Planets9 3.4 Mass-Radius Relationship for Carbon Planets 13 3.5 Section Summary and Implications 15 4 Water -
OGLE 2004-BLG-254: a K3 III Galactic Bulge Giant Spatially Resolved by A
Astronomy & Astrophysics manuscript no. 4414arti c ESO 2018 January 9, 2018 OGLE 2004–BLG–254: a K3 III Galactic Bulge Giant spatially resolved by a single microlens⋆ A. Cassan1,2,3, J.-P. Beaulieu1,3, P. Fouqu´e1,4, S. Brillant1,5, M. Dominik1,6, J. Greenhill1,7, D. Heyrovsk´y8, K. Horne1,6, U.G. Jørgensen1,9, D. Kubas1,5, H.C. Stempels6, C. Vinter1,9, M.D. Albrow1,12, D. Bennett1,13, J.A.R. Caldwell1,14,15, J.J. Calitz1,16, K. Cook1,17, C. Coutures1,18, D. Dominis1,19, J. Donatowicz1,20, K. Hill1,7, M. Hoffman1,16, S. Kane1,21, J.-B. Marquette1,3, R. Martin1,22, P. Meintjes1,16, J. Menzies1,23, V.R. Miller12, K.R. Pollard1,12, K.C. Sahu1,14, J. Wambsganss1,2, A. Williams1,22, A. Udalski10,11, M.K. Szyma´nski10,11, M. Kubiak10,11, G. Pietrzy´nski10,11,24, I. Soszy´nski10,11,24, K. Zebru´n˙ 10,11, O. Szewczyk10,11, and Ł. Wyrzykowski10,11,25 (Affiliations can be found after the references) Received ¡date¿ / Accepted ¡date¿ ABSTRACT Aims. We present an analysis of OGLE 2004–BLG–254, a high-magnification (A 60) and relatively short duration (tE 13.2 days) microlensing event in which the source star, a Bulge K-giant, has been spatially resolved◦ ≃ by a point-like lens. We seek to determine≃ the lens and source distance, and provide a measurement of the linear limb-darkening coefficients of the source star in the I and R bands. We discuss the derived values of the latter and compare them to the classical theoretical laws, and furthermore examine the cases of already published microlensed GK-giants limb-darkening measurements. -
Cycle 12 Abstract Catalog
Cycle 12 Abstract Catalog Generated April 04, 2003 ================================================================================ Proposal Category: GO Scientific Category: ISM AND CIRCUMSTELLAR MATTER ID: 9718 Title: SMC Extinction Curve Towards a Quiescent Molecular Cloud PI: Francois Boulanger PI Institution: Institut d'Astrophysique Spatiale The lack of 2175 A bump in the SMC extinction curve is interpreted as an absence of small carbon grains. ISO Mid-IR observations support this interpretation by showing that PAH features are absent in the spectra of SMC and LMC massive star forming regions. However, the only ISO observation of an SMC quiescent molecular cloud shows all PAH features, indicating a PAH abundance relative to large dust grains similar to that of Milky Way clouds. We identified a reddened B2III star associated with this cloud. We propose to observe it with STIS. This observation will provide the first measure of the extinction properties of SMC dust away from star forming regions. It will allow us to disentangle the effects of metallicity and massive stars on the SMC extinction curve and dust composition and to assess the relevance of the SMC bump-free extinction curve to low metallicity and/or starburst galaxies in general. ================================================================================ Proposal Category: GO Scientific Category: STELLAR POPULATIONS ID: 9719 Title: Search For Metallicity Spreads in M31 Globular Clusters PI: Terry Bridges PI Institution: Anglo-Australian Observatory Our recent deep HST photometry of the M31 halo globular cluster (GC) Mayall~II, also called G1, has revealed a red-giant branch with a clear spread that we attribute to an intrinsic metallicity dispersion of at least 0.4 dex in [Fe/H]. -
Orders of Magnitude (Length) - Wikipedia
03/08/2018 Orders of magnitude (length) - Wikipedia Orders of magnitude (length) The following are examples of orders of magnitude for different lengths. Contents Overview Detailed list Subatomic Atomic to cellular Cellular to human scale Human to astronomical scale Astronomical less than 10 yoctometres 10 yoctometres 100 yoctometres 1 zeptometre 10 zeptometres 100 zeptometres 1 attometre 10 attometres 100 attometres 1 femtometre 10 femtometres 100 femtometres 1 picometre 10 picometres 100 picometres 1 nanometre 10 nanometres 100 nanometres 1 micrometre 10 micrometres 100 micrometres 1 millimetre 1 centimetre 1 decimetre Conversions Wavelengths Human-defined scales and structures Nature Astronomical 1 metre Conversions https://en.wikipedia.org/wiki/Orders_of_magnitude_(length) 1/44 03/08/2018 Orders of magnitude (length) - Wikipedia Human-defined scales and structures Sports Nature Astronomical 1 decametre Conversions Human-defined scales and structures Sports Nature Astronomical 1 hectometre Conversions Human-defined scales and structures Sports Nature Astronomical 1 kilometre Conversions Human-defined scales and structures Geographical Astronomical 10 kilometres Conversions Sports Human-defined scales and structures Geographical Astronomical 100 kilometres Conversions Human-defined scales and structures Geographical Astronomical 1 megametre Conversions Human-defined scales and structures Sports Geographical Astronomical 10 megametres Conversions Human-defined scales and structures Geographical Astronomical 100 megametres 1 gigametre -
Eric Agol – Bibliography
Eric Agol | Curriculum Vitae Department of Astronomy, Box 351580, University of Washington, Seattle, WA 98195-1580 Ó (206) 543-7106 • Q [email protected] • faculty.washington.edu/agol/ Professor of Astronomy, Adjunct Professor of Physics. Previous Employment University of Washington Seattle + Professor 2017 – present Department of Astronomy; Adjunct in Physics. University of Washington Seattle + Associate Professor 2009 –2017 University of Washington Seattle + Assistant Professor 2003 – 2009 Caltech Pasadena + Chandra Fellow 2000 – 2003 Johns Hopkins University Baltimore + Postdoctoral Fellow 1997 – 2000 Education Academic Qualifications................................................... ........................................... University of California Santa Barbara + PhD, Department of Physics, Astrophysics 1992–1997 University of California Berkeley + BA, Physics and Mathematics 1988–1992 Dissertation................................................... ................................................... ......... + ‘The Effects of Magnetic Fields, Absorption, and Relativity on the Polarization of Accretion Disks around Supermassive Black Holes.’ Advisor: Omer Blaes. Selected Research Accomplishments: + Created grid of models for Quasars (Hubeny, Agol et al. 2000; Agol 1997). + Computed optically-thin general-relativistic ray-tracing model, and proposed experiment for imaging the shadow of the Galactic Center black hole (Falcke, Melia & Agol 2000), which culminated in the Event Horizon Telescope. + Derived fast, analytic transit model for -
Transiting Extrasolar Planetary Candidates in the Galactic Bulge
1 To appear in NATURE, October 5, 2006 issue Transiting extrasolar planetary candidates in the Galactic bulge Kailash C. Sahu*, Stefano Casertano*, Howard E. Bond*, Jeff Valenti*, T. Ed Smith*, Dante Minniti¶, Manuela Zoccali¶, Mario Livio*, Nino Panagia*, Nikolai Piskunov#, Thomas M. Brown*, Timothy Brown†, Alvio Renzini‡, R. Michael Rich§, Will Clarkson*, Stephen Lubow* *Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 †High Altitude Observatory, 3450 Mitchell Lane, Boulder, CO 80307 ¶Universidad Catolica de Chile, Av. Vicuña Mackenna 4860, Santiago 22, Chile #Uppsala University, Box 515, S-751 20 Uppsala, SWEDEN ‡INAF-Osservatorio Astronomico di Padova, Vicolo dell'Osservatorio 5, 35122 Padova, Italy §University of California at Los Angeles, Los Angeles, CA 90095-1562 More than 200 extrasolar planets have been discovered around relatively nearby stars, primarily through the Doppler line shifts owing to the reflex motions of their host stars, and more recently through transits of some planets across the face of the host stars. The detection of planets with the shortest known periods, 1.2 to 2.5 days, has mainly resulted from transit surveys which have generally targeted stars more massive than 0.75 M⊙, where M⊙ is the mass of the Sun. Here we report the results from a planetary transit search performed in a rich stellar field towards the Galactic bulge. We discovered 16 candidates with orbital periods between 0.4 and 4.2 days, five of which orbit stars of 0.44 to 0.75 M⊙. In two cases, radial-velocity measurements support the planetary nature of the companions. Five candidates have orbital periods below 1.0 day, constituting a new class of ultra-short-period planets (USPPs), which occur only around stars of less than 0.88 M⊙. -
December 1997
No. 90 – December 1997 T E L E S C O P E S A N D I N S T R U M E N T A T I O N A Deep Field with the Upgraded NTT S. D’ODORICO, ESO This colour deep image has been prepared from 4 deep images through the filters B, V, r and i obtained with the SUSI CCD imager at the ESO NTT. The image covers a 2.2 × 2.2 arcmin “emp- ty” field centred about 2 arcminutes south of the z = 4.7 QSO BR 1202- 0725. The four images result from the co-addition of dithered short integra- tions for a total of 52,800, 23,400, 23,400 and 16,200 seconds in the four bands, and the co-added images have average FWHMs of 0.84, 0.80, 0.80 and 0.68 arcsec respectively. The data were obtained for a scientif- ic programme approved for the ESO Period 58 and aimed at the study of the photometric redshift distribution of the faint galaxies and of gravitational lens- ing effects in the field. The P.I. of the proposal is Sandro D’Odorico and the Co-P.I. are J. Bergeron, H.M. Adorf, S. Charlot, D. Clements, S. Cristiani, L. da Costa, E. Egami, A. Fontana, B. Fort, L. Gautret, E. Giallongo, R. Gilmozzi, R.N. Hook, B. Leibundgut, Y. Mellier, P. Petitjean, A. Renzini, S. Savaglio, P. Shaver, S. Seitz and L. Yan. The pro- gramme was executed in service mode by the NTT team in February through April 1997 in photometric nights with seeing better than 1 arcsec. -
A Data Viewer for R
Paul Murrell A Data Viewer for R A Data Viewer for R Paul Murrell The University of Auckland July 30 2009 Paul Murrell A Data Viewer for R Overview Motivation: STATS 220 Problem statement: Students do not understand what they cannot see. What doesn’t work: View() A solution: The rdataviewer package and the tcltkViewer() function. What else?: Novel navigation interface, zooming, extensible for other data sources. Paul Murrell A Data Viewer for R STATS 220 Data Technologies HTML (and CSS), XML (and DTDs), SQL (and databases), and R (and regular expressions) Online text book that nobody reads Computer lab each week (worth 0.5%) + three Assignments 5 labs + one assignment on R Emphasis on creating and modifying data structures Attempt to use real data Paul Murrell A Data Viewer for R Example Lab Question Read the file lab10.txt into R as a character vector. You should end up with a symbol habitats that prints like this (this shows just the first 10 values; there are 192 values in total): > head(habitats, 10) [1] "upwd1201" "upwd0502" "upwd0702" [4] "upwd1002" "upwd1102" "upwd0203" [7] "upwd0503" "upwd0803" "upwd0104" [10] "upwd0704" Paul Murrell A Data Viewer for R The file lab10.txt upwd1201 upwd0502 upwd0702 upwd1002 upwd1102 upwd0203 upwd0503 upwd0803 upwd0104 upwd0704 upwd0804 upwd1204 upwd0805 upwd1005 upwd0106 dnwd1201 dnwd0502 dnwd0702 dnwd1002 dnwd1102 dnwd1202 dnwd0103 dnwd0203 dnwd0303 dnwd0403 dnwd0503 dnwd0803 dnwd0104 dnwd0704 dnwd0804 dnwd1204 dnwd0805 dnwd1005 dnwd0106 uppl0502 uppl0702 uppl1002 uppl1102 uppl0203 uppl0503 -
A Review of the History, Theory and Observations Of
A REVIEW OF THE HISTORY, THEORY AND OBSERVATIONS OF GRAVITATIONAL MICROLENSING UP UNTIL THE PRESENT DAY A thesis submitted in fulfilment of the requirements for the Degree of Master of Science in Astronomy in the University of Canterbury by T. McClelland University of Canterbury 2008 TABLE OF CONTENTS ABSTRACT CHAPTERS 1 The Early History of Lensing Theory ...............................................................................................................................4 Newtonian Mechanics General Relativity 1960 developments Detection 2 Lens Theory and Lensing Phenomena .............................................................................................................................40 The Deflection of Light by Massive Objects Newtonian Mechanics General Relativistic Mechanics Gravitational Lensing Lens Equation Einstein Rings Gravitational Microlensing Quasar Microlensing Light curve variations and implications Parallax Caustic Curves 3 Modern Techniques and their Applications .............................................................................................................................66 Inverse Ray Technique Inverse Polygon Mapping Difference Imaging Astrometry 4 Applications .............................................................................................................................70 Dark Matter Binary Systems Extrasolar Planets Black Holes Stellar Mass Stellar Atmospheres Quasar Abnormalities Understanding Galactic Structure 5 Systematic Observational Networks .............................................................................................................................84 -
The COLOUR of CREATION Observing and Astrophotography Targets “At a Glance” Guide
The COLOUR of CREATION observing and astrophotography targets “at a glance” guide. (Naked eye, binoculars, small and “monster” scopes) Dear fellow amateur astronomer. Please note - this is a work in progress – compiled from several sources - and undoubtedly WILL contain inaccuracies. It would therefor be HIGHLY appreciated if readers would be so kind as to forward ANY corrections and/ or additions (as the document is still obviously incomplete) to: [email protected]. The document will be updated/ revised/ expanded* on a regular basis, replacing the existing document on the ASSA Pretoria website, as well as on the website: coloursofcreation.co.za . This is by no means intended to be a complete nor an exhaustive listing, but rather an “at a glance guide” (2nd column), that will hopefully assist in choosing or eliminating certain objects in a specific constellation for further research, to determine suitability for observation or astrophotography. There is NO copy right - download at will. Warm regards. JohanM. *Edition 1: June 2016 (“Pre-Karoo Star Party version”). “To me, one of the wonders and lures of astronomy is observing a galaxy… realizing you are detecting ancient photons, emitted by billions of stars, reduced to a magnitude below naked eye detection…lying at a distance beyond comprehension...” ASSA 100. (Auke Slotegraaf). Messier objects. Apparent size: degrees, arc minutes, arc seconds. Interesting info. AKA’s. Emphasis, correction. Coordinates, location. Stars, star groups, etc. Variable stars. Double stars. (Only a small number included. “Colourful Ds. descriptions” taken from the book by Sissy Haas). Carbon star. C Asterisma. (Including many “Streicher” objects, taken from Asterism.