Regulus March-April 1991
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FOIA Logs for US Army for 2000
Description of document: FOIA CASE LOGS for: United States Army, Alexandria, VA for 2000 - 2003 Released date: 2003 Posted date: 04-March-2008 Date/date range of document: 03-January-2000 – 27-March-2003 Source of document: Department Of The Army U.S. Army Freedom of Information and Privacy Office Casey Building, Suite 144 Attn: JDRP-RDF 7701 Telegraph Road Alexandria, VA 22315-3905 Phone: (703) 428-6494 Fax: (703) 428-6522 Email: [email protected] The governmentattic.org web site (“the site”) is noncommercial and free to the public. The site and materials made available on the site, such as this file, are for reference only. The governmentattic.org web site and its principals have made every effort to make this information as complete and as accurate as possible, however, there may be mistakes and omissions, both typographical and in content. The governmentattic.org web site and its principals shall have neither liability nor responsibility to any person or entity with respect to any loss or damage caused, or alleged to have been caused, directly or indirectly, by the information provided on the governmentattic.org web site or in this file 2000 FOIA# Rec'd Closed Susp Days Subject Refer By Control # Class AO Action 1 Action 2 Action 3 # Refer Q 00-0433 01/03/2000 04/06/2000 01/14/2000 67 Information on what the name or number of the group or company U SLF CATEGORY 9 0 S stationed in St. John's, Newfoundland during World War II in 1945 (E-Mail) 00-0434 01/03/2000 01/04/2000 01/14/2000 2 Information on the mortality rate of the former -
Arxiv:2009.02409V1
Draft version September 8, 2020 Typeset using LATEX preprint style in AASTeX63 Spectroscopic Detection of the Pre-White Dwarf Companion of Regulus Douglas R. Gies,1 Kathryn V. Lester,1 Luqian Wang,1 Andrew Couperus,1 Katherine Shepard,1 Coralie Neiner,2 Gregg A. Wade,3 David W. Dunham,4 and Joan B. Dunham4 1Center for High Angular Resolution Astronomy and Department of Physics and Astronomy, Georgia State University, P. O. Box 5060, Atlanta, GA 30302-5060, USA 2LESIA, Observatoire de Paris, PSL University, CNRS, Sorbonne Universit´e, Univ. Paris Diderot, Sorbonne Paris Cit´e, 5 place Jules Janssen, F-92195 Meudon, France 3 Department of Physics and Space Science, Royal Military College of Canada, P.O. Box 17000 Station Forces, Kingston, ON K7K 0C6, Canada 4IOTA, 7913 Kara Court, Greenbelt, MD 20770, USA ABSTRACT Mass transfer in an interacting binary will often strip the mass donor of its entire envelope and spin up the mass gainer to near critical rotation. The nearby B-type star Regulus represents a binary in the post-mass transfer stage: it is a rapid rotator with a very faint companion in a 40 d orbit. Here we present the results of a search for the spectral features of the stripped-down star in an extensive set of high S/N and high resolution spectra obtained with the CFHT/ESPaDOnS and TBL/NARVAL spectrographs. We first determine revised orbital elements in order to set accurate estimates of the orbital Doppler shifts at the times of observation. We then calculate cross-correlation functions of the observed and model spectra, and we search for evidence of the companion signal in the residuals after removal of the strong primary component. -
Spectral Classification of B-Type Stars
Spectral Chapter 4 Classification Gray & Corbally of B-type Katie Lester Stars Image Credit: NASA -APOD 9/13/13 Properties Temperature: 10,000 – 30,000 K Mass: 2 – 20 Msun Luminosity: 60 – 30,000 Lsun Abundance: 0.1% of all stars (Carroll & Ostlie) Image Credit: ESO Formation and Evolution • Form in molecular clouds in spiral arms of the galaxy • Usually found in binary systems with other massive stars • Main sequence lifetime: 10-100 million years • Evolves to become a supergiant • Dies in a SN explosion to become white dwarf or neutron star N11 star forming region in the LMC Image Credit: ESA/NASA Famous B stars • Rigel (Orion) – B8 Ia • Regulus (Leo) – B7 V • Pleiades Cluster (M45) – Seven brightest are B or Be type stars Many of the brightest naked eye stars in the sky are B stars! Image Credit: ESA/ESO Image Credit: Carroll & Ostlie General spectral characteristics • Energy distribution peaks in the UV and blue • Ex) B5 peaks around 1800Å • Spectra dominated by H I and He I lines • Some lines from ionized metals • Ex) O II, Si II, Mg II (Gray & Corbally) Early B stars (B0-B3) Decreasing ↓ Temperature: Optical • Balmer line strength ↑ • He I lines peak at B2 UV • Si III / Si IV ratio • C II / C III ratio • P Cygni resonance lines Early B stars (B0-B3) Increasing ↑ Luminosity: Optical • He I strength ↓ • Balmer line width ↓ • Si II and O II strength ↑ UV • Al III strength ↑ • Fe III strength ↑ Late B stars (B3-B9) Decreasing ↓ Temperature: Optical • Balmer line strength ↑ • He I strength ↓ • Mg II strength ↑ UV • Si II / Si III ratio -
April 2016 BRAS Newsletter
April 2016 Issue th Next Meeting: Monday, April 11 at 7PM at HRPO (2nd Mondays, Highland Road Park Observatory) April 6th through April 10th is our annual Hodges Gardens Star Party. You can pre-register using the form on the BRAS website. If you have never attended this star party, make plans to attend this one. What's In This Issue? President’s Message Photos: BRAS Telescope donated to EBRP Library Secretary's Summary of March Meeting Recent BRAS Forum Entries 20/20 Vision Campaign Message from the HRPO Astro Short: Stellar Dinosaurs? International Astronomy Day Observing Notes: Leo The Lion, by John Nagle Newsletter of the Baton Rouge Astronomical Society April 2016 Page 2 President’s Message There were 478 people who stopped by the BRAS display at the March 19th ―Rockin at the Swamp‖ event at the Bluebonnet Swamp and Nature Center. I give thanks to all our volunteers for our success in this outreach event. April 6th through April 10th is our annual Hodges Gardens Star Party. You can pre-register on the BRAS website, or register when you arrive (directions are on the BRAS website). If you have never attended a star party, of if you are an old veteran star partier; make plans to attend this one. Our Guest Speaker for the BRAS meeting on April 11th will be Dr. Joseph Giaime, Observatory Head, LIGO Livingston (Caltech), Professor of Physics and Astronomy (LSU). Yes, he will be talking about gravity waves and the extraordinary discovery LIGO has made. We need volunteers to help at our display on Earth Day on Sunday, April 17th. -
Teacher Activity Packet: Observation Guide March 22-April 4, 2011
Teacher Activity Packet: Observation Guide www.globeatnight.org March 22-April 4, 2011 Encourage your students to participate in a world-wide Five Easy Star-Hunting Steps: citizen science campaign to observe and record the (www.globeatnight.org/observe.html) magnitude of visible stars as a means of measuring light pollution in a given location. Because the data collec- 1) Find your latitude and longitude tion occurs in the evening, this is an excellent opportu- by using any of the following methods: nity to get parents involved in a learning activity with a. Use a GPS unit where you take a measurement. their child. Participants will learn how to locate the Report as many decimal places as the unit provides. b. Visit http://eo.ucar.edu/geocode/ on-line. Input constellation Leo. They will learn stars have different your location. Or input your city; zoom in/out and magnitudes of brightness in the night sky and that this pan around until you find your location. Double-click information is of interest to scientists studying light pol- and the latitude and longitude will be displayed. lution. Using the information provided your students c. Use topographic map of your area. will collect data and report their findings to the GLOBE d. Determine your latitude and longitude with the at Night online database. The data will then be ana- interactive tool when reporting observations on the lyzed and mapped for participants to see the results of GLOBE at Night Web site. this global campaign. 2) Find Leo by going outside an hour after You may choose to have GLOBE at Night be a part of sunset (approximately between 8-10 pm local time) your planned curricula or a completely independent ex- a. -
Adrian Zielonka's December 2020 Astronomy and Space News
Astronomy News Night Sky 2020 - December Sunrise Sunset Mercury Venus Rises 1st – 7:53am 1st – 4:07pm 1st – 5:19am 10th – 8:04am 10th – 4:04pm Not Visible 10th – 5:46am 20th – 8:12am 20th – 4:06pm this month. 20th – 6:16am 30th – 8:15am 30th – 4:13pm 30th – 6:43am Moon Rise Moon Set Moon Rise Moon Set - - - - - - - 1st – 8:54am 20th – 12:16pm (ESE) 20th – 10:46pm 1st – 4:52pm 2nd – 9:56am 21st – 12:33pm 21st – 11:55pm 2nd – 5:36pm 3rd – 10:50am 22nd – 12:48pm (E) 23rd – 1:02am (W) 3rd – 6:31pm 4th – 11:35am 23rd – 1:03pm 24th – 2:09am 4th – 7:37pm 5th – 12:10pm 24th – 1:18pm 25th – 3:16am 5th – 8:50pm 6th – 12:38pm 25th – 1:35pm (ENE) 26th – 4:24am (WNW) 6th – 10:07pm (ENE) 7th – 1:01pm (WNW) 26th – 1:55pm 27th – 5:33am 7th – 11:26pm 8th – 1:21pm 27th – 2:19pm 28th – 6:41am 9th – 12:46am 9th – 1:39pm (W) 28th – 2:50pm 29th – 7:46am 10th – 2:08am (E) 10th – 1:58pm 29th – 3:31pm 30th – 8:44am 11th – 3:32am 11th – 2:18pm 30th – 4:23pm 31st – 9:33am 12th – 4:58am (ESE) 12th – 2:42pm (WSW) 31st – 5:27pm - - - - - - - 13th – 6:26am 13th – 3:13pm - - - - - - - Moon Phases 14th – 7:51am 14th – 3:53pm All times Last Quarter – 8th 15th – 9:07am 15th – 4:45pm in notes are set New Moon – 14th 16th – 10:09am 16th – 5:50pm for First Quarter – 21st 17th – 10:56am 17th – 7:03pm Somerton Full Moon – 30th 18th – 11:30am 18th – 8:19pm unless stated 19th – 11:56am +4.5 19th – 9:34pm (WSW) A useful site: www.heavens- A S Zielonka above.com There is a planned launch (no earlier than December) of SpaceX CRS-21 Cargo mission to the International Space Station (ISS). -
Download a Sample Issue
ASTRONOMERS FROM ANTIQUITY PPAGEage 164 MARCH/APRIL 2019 $5 Probing for Planets Space agencies prepare next generation of exoplanet hunters THE UNIVERSITY OF TEXAS AT AUSTIN Mc DONALD OBSERVATORY STARDATE STAFF MARCH/APRIL • Vol. 47, No. 2 EXECUTIVE EDITOR Damond Benningfield EDITOR Rebecca Johnson ART DIRECTOR C.J. Duncan EATURES EPARtmENts TECHNICAL EDITOR F D Dr. Tom Barnes CONTRIBUTING EDITOR Alan MacRobert 4 Poets, Philosophers, Queens, Astronomers MERLIN 3 MARKETING MANAGER Casey Walker Early women astronomers drafted MARKETING ASSISTANT calendars, plotted eclipses, built SKY CALENDAR MARCH/APRIL 10 Joanne Duffy observatories, and helped shape humanity’s early understanding of the THE STARS IN MARCH/APRIL 12 universe For information about StarDate or other programs of the McDonald Observatory By Jasmin Fox-Skelly Education and Outreach Office, contact ASTROMISCELLANY 14 us at 512-471-5285. For subscription orders only, call 800-STARDATE. 16 Kepler Passes the Torch ASTRONEWS 20 StarDate (ISSN 0889-3098) is published As a successful planet-hunting bimonthly by the McDonald Observatory Resetting the Clock on Saturn’s Rings Education and Outreach Office, The Uni- spacecraft came to the end of its mission, versity of Texas at Austin, 2515 Speedway, Chasing Away Planet Nine Stop C1402, Austin, TX 78712. © 2019 a successor took flight. Several others are The University of Texas at Austin. Annual expected to follow in the next decade Chillin’ Under the Sun subscription rate is $26 in the United States. Subscriptions may be paid for using By Rebecca Johnson Birth of a Black Hole, or Death by Black Hole? credit card or money orders. The University of Texas cannot accept checks drawn on Gaia Spies Galaxy-Hopping Stars foreign banks. -
Family Activity Packet: Observation Guide March 22 - April 4, 2011
Family Activity Packet: Observation Guide www.globeatnight.org March 22 - April 4, 2011 Students and families are encouraged to participate in a Five Easy Star-Hunting Steps: global campaign to observe and record the magnitude (www.globeatnight.org/observe.html) of visible stars as a means of measuring light pollution in a given location. Your contributions to the online da- 1) Find your latitude and longitude tabase will document the visible nighttime sky. By lo- by using any of the following methods: cating and observing the constellation Leo in the night a. Use a GPS unit where you take a measurement. Report as many decimal places as the unit provides. sky, students from around the world will learn how the b. Visit http://eo.ucar.edu/geocode/ on-line. Input lights in their community contribute to light pollution. your location. Or input your city; zoom in/out and pan around until you find your location. Double-click Materials Needed: and the latitude and longitude will be displayed. • GLOBE at Night Teacher or Family Activity Packet c. Use topographic map of your area. • Something to write on (clipboard or cardboard) d. Determine your latitude and longitude with the • Something to write with (pencil or pen) interactive tool when reporting observations on the • Red light to preserve night vision (A red light can be GLOBE at Night Web site. made by covering a flashlight with a brown paper bag or red cellophane and securing the covering with a rub- 2) Find Leo by going outside an hour after ber band to be sure it doesn’t slip while making the ob- sunset (approximately between 8-10 pm local time) servation.) a. -
Extrasolar Planets and Their Host Stars
Kaspar von Braun & Tabetha S. Boyajian Extrasolar Planets and Their Host Stars July 25, 2017 arXiv:1707.07405v1 [astro-ph.EP] 24 Jul 2017 Springer Preface In astronomy or indeed any collaborative environment, it pays to figure out with whom one can work well. From existing projects or simply conversations, research ideas appear, are developed, take shape, sometimes take a detour into some un- expected directions, often need to be refocused, are sometimes divided up and/or distributed among collaborators, and are (hopefully) published. After a number of these cycles repeat, something bigger may be born, all of which one then tries to simultaneously fit into one’s head for what feels like a challenging amount of time. That was certainly the case a long time ago when writing a PhD dissertation. Since then, there have been postdoctoral fellowships and appointments, permanent and adjunct positions, and former, current, and future collaborators. And yet, con- versations spawn research ideas, which take many different turns and may divide up into a multitude of approaches or related or perhaps unrelated subjects. Again, one had better figure out with whom one likes to work. And again, in the process of writing this Brief, one needs create something bigger by focusing the relevant pieces of work into one (hopefully) coherent manuscript. It is an honor, a privi- lege, an amazing experience, and simply a lot of fun to be and have been working with all the people who have had an influence on our work and thereby on this book. To quote the late and great Jim Croce: ”If you dig it, do it. -
Surveying Stars
Northeastern Illinois University Surveying Stars Greg Anderson Department of Physics & Astronomy Northeastern Illinois University Fall 2018 c 2012-2018G. Anderson Universe: Past, Present & Future – slide 1 / 102 Northeastern Illinois Overview University The Night Sky Luminosity & Brightness Distance & Parallax Stellar Temperatures HR Diagrams Binary Systems Stellar Masses Star Clusters Review c 2012-2018G. Anderson Universe: Past, Present & Future – slide 2 / 102 Northeastern Illinois University The Night Sky Cassiopeia Stars in the Night Sky Star Trails Lower Canyons Luminosity & Brightness Distance & Parallax Stellar The Night Sky Temperatures HR Diagrams Binary Systems Stellar Masses Star Clusters Review c 2012-2018G. Anderson Universe: Past, Present & Future – slide 3 / 102 c T. Credner & S. Kohle, AlltheSky.com Northeastern Illinois Stars in the Night Sky University • Outside of the city, on very clear nights you can see thousands of stars. • Of the 25 brightest stars, the furthest away is Deneb (≈ 800 pc). • Under the best conditions the furthest star we can see with the naked eye is a few thousand light years away. c 2012-2018G. Anderson Universe: Past, Present & Future – slide 5 / 102 G. Anderson: Star Trails in the Lower Canyons Northeastern Illinois University The Night Sky Luminosity & Brightness Luminosity Q: L Units Stellar L η Carinae Blackbody Rad. Relative L Luminosity & Q: Star L Motorcycle Q: b vs L b vs. d Brightness App Brightness Bulbs Q: L vs r Q: Units for b Magnitude Sys Apparent Magnitude m chart Bright Stars Q: Visible limit Stars vs. Limiting Magnitude Darks Sky Abs Mag (M) Q: c Vega2012-2018G. Anderson Universe: Past, Present & Future – slide 7 / 102 Distance & Northeastern Illinois Luminosity University Luminosity: The total amount of power (energy per unit time) emitted by a star or other object. -
B-Type Main-Sequence Star
B-type main-sequence star A B-type main-sequence star (B V) is a main- sequence (hydrogen-burning) star of spectral type B and luminosity class V. These stars have from 2 to 16 times the mass of the Sun and surface temperatures between 10,000 and 30,000 K.[2] B-type stars are extremely luminous and blue. Their spectra have neutral helium, which are most prominent at the B2 subclass, and moderate hydrogen lines. Examples include Regulus and Algol A.[3] This class of stars was introduced with the Harvard Part of the constellation of Carina, Epsilon Carinae is an sequence of stellar spectra and published in the Revised example of a double star featuring a main-sequence B-type Harvard photometry catalogue. The definition of type star. B-type stars was the presence of non-ionized helium lines with the absence of singly ionized helium in the blue-violet portion of the spectrum. All of the spectral classes, including Typical Stellar Properties[1] the B type, were subdivided with a numerical suffix that indicated the Spectral Radius Mass T degree to which they approached the next classification. Thus B2 is 1/5 eff log g Type R☉ M☉ (K) of the way from type B (or B0) to type A.[4][5] B0V 10 17 25,000 4 Later, however, more refined spectra showed lines of ionized helium for B1V 6.42 13.21 25,400 3.9 stars of type B0. Likewise, A0 stars also show weak lines of non-ionized B2V 5.33 9.11 20,800 3.9 helium. -
How Astronomical Objects Are Named
How Astronomical Objects Are Named Jeanne E. Bishop Westlake Schools Planetarium 24525 Hilliard Road Westlake, Ohio 44145 U.S.A. bishop{at}@wlake.org Sept 2004 Introduction “What, I wonder, would the science of astrono- use of the sky by the societies of At the 1988 meeting in Rich- my be like, if we could not properly discrimi- the people that developed them. However, these different systems mond, Virginia, the Inter- nate among the stars themselves. Without the national Planetarium Society are beyond the scope of this arti- (IPS) released a statement ex- use of unique names, all observatories, both cle; the discussion will be limited plaining and opposing the sell- ancient and modern, would be useful to to the system of constellations ing of star names by private nobody, and the books describing these things used currently by astronomers in business groups. In this state- all countries. As we shall see, the ment I reviewed the official would seem to us to be more like enigmas history of the official constella- methods by which stars are rather than descriptions and explanations.” tions includes contributions and named. Later, at the IPS Exec- – Johannes Hevelius, 1611-1687 innovations of people from utive Council Meeting in 2000, many cultures and countries. there was a positive response to The IAU recognizes 88 constel- the suggestion that as continuing Chair of with the name registered in an ‘important’ lations, all originating in ancient times or the Committee for Astronomical Accuracy, I book “… is a scam. Astronomers don’t recog- during the European age of exploration and prepare a reference article that describes not nize those names.