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Volume 76 Nos 3 & in This Issue
Volume 76 Nos 3 & 4 April 2017 In this issue: News notes, New Director at SAAO, Pro -Am Interaction with NASA Juno mission, Six hours with our Home Star, Colloquia a nd Seminars EDITORIAL Mr Case Rijsdijk (Editor, MNASSA ) BOARD Mr Auke Slotegraaf (Editor, Sky Guide Africa South ) Mr Christian Hettlage (Webmaster) Mr James Smith (Web Manager) Prof M.W. Feast (Member, University of Cape Town) Prof B. Warner (Member, University of Cape Town) MNASSA Mr Case Rijsdijk (Editor, MNASSA ) PRODUCTION Dr Ian Glass (Assistant Editor) Vacant (Book Review Editor) Willie Koorts (Consultant) EDITORIAL MNASSA, PO Box 9, Observatory 7935, South Africa ADDRESSES Email: [email protected] Web Manager: [email protected] MNASSA Download Page: www.mnassa.org.za SUBSCRIPTIONS MNASSA is available for free download on the Internet ADVERTISING Advertisements may be placed in MNASSA at the following rates per insertion: full page R400, half page R200, quarter page R100. Small advertisements R2 per word. Enquiries should be sent to the editor at [email protected] CONTRIBUTIONS MNASSA mainly serves the Southern African astronomical community. Articles may be submitted by members of this community or by those with strong connections. Else they should deal with matters of direct interest to the community . MNASSA is published on the last day of every second month and articles are due one month before the publication date. RECOGNITION Articles from MNASSA appear in the NASA/ADS data system. Cover: Image of Jupiter taken by Clyde Foster on 2 February 2017. See article on page 68. mnassa Vol 76 Nos 3 & 4 April 2017 Editorial Rec ently I have received many submissions, for which I am really grateful, but they come in a variety of formats and styles. -
Information Bulletin on Variable Stars
COMMISSIONS AND OF THE I A U INFORMATION BULLETIN ON VARIABLE STARS Nos November July EDITORS L SZABADOS K OLAH TECHNICAL EDITOR A HOLL TYPESETTING K ORI ADMINISTRATION Zs KOVARI EDITORIAL BOARD L A BALONA M BREGER E BUDDING M deGROOT E GUINAN D S HALL P HARMANEC M JERZYKIEWICZ K C LEUNG M RODONO N N SAMUS J SMAK C STERKEN Chair H BUDAPEST XI I Box HUNGARY URL httpwwwkonkolyhuIBVSIBVShtml HU ISSN COPYRIGHT NOTICE IBVS is published on b ehalf of the th and nd Commissions of the IAU by the Konkoly Observatory Budap est Hungary Individual issues could b e downloaded for scientic and educational purp oses free of charge Bibliographic information of the recent issues could b e entered to indexing sys tems No IBVS issues may b e stored in a public retrieval system in any form or by any means electronic or otherwise without the prior written p ermission of the publishers Prior written p ermission of the publishers is required for entering IBVS issues to an electronic indexing or bibliographic system to o CONTENTS C STERKEN A JONES B VOS I ZEGELAAR AM van GENDEREN M de GROOT On the Cyclicity of the S Dor Phases in AG Carinae ::::::::::::::::::::::::::::::::::::::::::::::::::: : J BOROVICKA L SAROUNOVA The Period and Lightcurve of NSV ::::::::::::::::::::::::::::::::::::::::::::::::::: :::::::::::::: W LILLER AF JONES A New Very Long Period Variable Star in Norma ::::::::::::::::::::::::::::::::::::::::::::::::::: :::::::::::::::: EA KARITSKAYA VP GORANSKIJ Unusual Fading of V Cygni Cyg X in Early November ::::::::::::::::::::::::::::::::::::::: -
March 2020 BRAS Newsletter
A Monthly Meeting March 11th at 7:00 PM at HRPO (Monthly meetings are on 2nd Mondays, Highland Road Park Observatory). Presentation: Dr. Manas Gartia, (Dept. of Mechanical and Industrial Engineering at LSU), presents his research into using the natural radiation in space as a means of purifying water for long-term space travel. 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 – Astronomy On Tap Messages from the HRPO Friday Night Lecture Series Science Academy Solar Viewing Stem Expansion Plus Night Edge of Night Starlink Watch Venusian Elongation Nano Days INTERNATIONAL ASTRONOMY DAY Observing Notes: Camelopardalis –The Giraffe & 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 22 March 2020 President’s Message For having such an unbelievably long January, February certainly seemed to fly by. I hope everybody had a fun Mardi Gras and is getting ready for the coming Spring and the galaxies that come into view with it. Unfortunately, that also means that the scourge of Daylight Saving Time is also upon us, and with new bills in the Louisiana legislature proposing a permanent switch to DST, I, for one, hope you take a moment to write, call, or visit with your elected representative to suggest their doing away with it altogether instead. There will have been a talk given at HRPO on this issue by the time this newsletter is published, so I hope some of you made it out. -
On the Hipparcos Photometry of Chemically Peculiar B, A, and F Stars?
ASTRONOMY & ASTROPHYSICS OCTOBER I 1998,PAGE93 SUPPLEMENT SERIES Astron. Astrophys. Suppl. Ser. 132, 93–97 (1998) On the Hipparcos photometry of chemically peculiar B, A, and F stars? Saul J. Adelman Department of Physics, The Citadel, 171 Moultrie Street, Charleston SC 29409, U.S.A. e-mail: [email protected] Received February 23; accepted March 20, 1998 Abstract. The Hipparcos photometry of the Chemically standard error as given in the Hipparcos Catalogue and Peculiar main sequence B, A, and F stars is examined the “amplitude”, the difference between the 95 th and for variability. Some non-magnetic CP stars, Mercury- 5 th percentile magnitudes from its Photometry Annex. Manganese and metallic-line stars, which according to The Hipparcos Catalogue gives the scatter (one-half the canonical wisdom should not be variable, may be vari- difference between the 85 th and 15 th percentile magni- able and are identified for further study. Some potentially tudes). Although the scatter and amplitude should cor- important magnetic CP stars are noted. relate with one another and with the standard error, the amplitude might be more sensitive to potentially eclipsing Key words: stars: early type — stars: chemically peculiar systems. Tables 1, 2, and 3 give the Hipparcos photometry for the HgMn, Am, and magnetic CP stars, respectively. For each star, two identifiers are normally given, the HR or HD number and the Hipparcos Catalogue number, the mean Hipparcos magnitude, its standard error, its am- 1. Introduction plitude, and variability comments including the period if known except for the magnetic CP stars. Photometry from the Hipparcos Satellite (European Space Agency (ESA) 1997) can be used to study stellar variabil- The standard error, the amplitude, and the scatter ity. -
IP1: CORBALLY, GRAY: Characteristics of Our Neighboring A-Stars
Characteristics of our neighboring A-stars C. J. Corbally Vatican Observatory Research Group, University of Arizona, Tucson, AZ 85721, USA [email protected] and R. O. Gray Department of Physics and Astronomy, Appalachian State University, Boone, NC 28608, USA [email protected] Abstract We have a project, under the aegis of the Nearby Stars (NStars) / Space Interferometry Mission Preparatory Science Program to obtain spectra, spectral types, and, where feasible, basic physical parameters for the 3600 dwarf and giant stars earlier than M0 within 40 parsecs of the Sun. There are 66 B-to-early-F stars among the first 664 stars analyzed in the northern hemisphere, and 37 of the same among a similar number of southern hemisphere stars. With these we can start looking at statistics of Ap, Am, 8 Boötis, and other A-type stars for a volume-limited sample, and we can find out just how well we know our neighbors. The project’s data are available on our website, http://stellar.phys.appstate.edu The Project The Nearby Stars (NStars) Spectroscopy Project, carried out jointly at Appalachian State University, the Vatican Observatory and the David Dunlap Observatory is now in its final phases. In this project we have been engaged in obtaining spectroscopic observations of all 3600 dwarf and giant stars earlier than M0 within a radius of 40 parsecs (Gray et al. 2003). These blue- violet spectra, obtained at classification resolution, are being used to obtain homogeneous, precise MK spectral types. In addition, these spectra are being used in conjunction with existing Strömgren uvby and Johnson-Cousins BVRI photometry and synthetic spectra to derive the basic astrophysical parameters for these stars (Teff, log(g) and [M/H]). -
CONTENTS Volume 76 Nos 3 & in This Issue
Volume 76 Nos 3 & 4 April 2017 Volume 76 Nos 3 & 4 April 2017 CONTENTS Editorial ................................ ................................ ................................ ................................ ... 61 News ................................ ................................ ................................ ................................ ........ 61 New Director Appointed for SAAO ................................................................ ................................ .............. 61 News Notes ................................ ................................ ................................ ............................ 63 A r obotic all sky monitor to observe one star for one year ................................ ................................. 63 SAAO helps to reveal seven new Earth -sized planets ................................ ................................ ............ 65 New highly inflated exoplanet spotted around nearby star ................................ ................................ 66 Pro-Am interaction on the NASA Juno mission to Jupiter ................................ ............... 68 Amateur Astronomical involvement ................................ ................................ .................. 69 Six Hours in the Life of our Home Star ................................ ................................ ................. 74 Seeing the sky all over again ................................ ................................ .............................. 81 Colloquia and Seminars ............................... -
THE 73Rd NAME-LIST of VARIABLE STARS
COMMISSIONS AND OF THE IAU INFORMATION BULLETIN ON VARIABLE STARS Number Konkoly Observatory Budap est April HU ISSN THE rd NAMELIST OF VARIABLE STARS The present rd NameList of Variable Stars compiled basically in the manner rst introduced in the th NameList IBVS No contains all data necessary for identication of new variables nally designated in The total number of designated variable stars not counting designated nonexisting stars or stars subsequently identied with earlierdesignated variables has now reached In the nearest future we are going to present two sp ecial NameLists containing variables discovered by the HIPPARCOS mission and in the frame of the OGLE pro ject The rd NameList consists of two tables Table contains the list of new variables arranged in the order of their right ascensions It gives the ordinal number and the des ignation of each variable its equatorial co ordinates for the equinox note that we have changed the standard accuracy For all stars but two we present right ascensions s 00 to and declinations to The co ordinates were found in the literature taken from p ositional catalogues including GSC or determined by the authors Sometimes the ac curacy may actually b e ab out seconds of arc For V and V Cas we could not improve the published rough co ordinates b ecause nding charts are not available the range of variability sometimes the column Min gives in parentheses the amplitude of light variation and the system of magnitudes used the symbols Rc Ic desig nate magnitudes in Cousinss RI system -
Contributions to the Nearby Stars (Nstars) Project: Spectroscopy of Stars Earlier Than M0 Within 40 Parsecs: the Northern Sample I
Contributions to the Nearby Stars (NStars) Project: Spectroscopy of Stars Earlier than M0 within 40 parsecs: The Northern Sample I. R.O. Gray Department of Physics and Astronomy Appalachian State University, Boone, NC 28608 [email protected] C.J. Corbally Vatican Observatory Research Group, Steward Observatory Tucson, AZ 85721-0065 [email protected] R.F. Garrison David Dunlap Observatory, Richmond Hill, Ontario [email protected] M.T. McFadden Department of Physics and Astronomy Appalachian State University, Boone, NC 28608 [email protected] P.E. Robinson Department of Physics and Astronomy Appalachian State University, Boone, NC 28608 arXiv:astro-ph/0308182v1 11 Aug 2003 ABSTRACT We have embarked on a project, under the aegis of the Nearby Stars (NStars)/ Space Interfer- ometry Mission Preparatory Science Program to obtain spectra, spectral types, and, where feasi- ble, basic physical parameters for the 3600 dwarf and giant stars earlier than M0 within 40 parsecs of the sun. In this paper we report on the results of this project for the first 664 stars in the north- ern hemisphere. These results include precise, homogeneous spectral types, basic physical pa- rameters (including the effective temperature, surface gravity and the overall metallicity, [M/H]) and measures of the chromospheric activity of our program stars. Observed and derived data pre- sented in this paper are also available on the project’s website http://stellar.phys.appstate.edu/. Subject headings: astronomical databases: surveys — stars: abundances — stars: activity — stars: fundamental parameters — stars: statistics 1 1. Introduction two gratings with 600 grooves mm−1 and 1200 grooves mm−1 and a thinned, back-illuminated The three institutions represented by the au- 1024 × 1024 Tektronix CCD operating in the thorship of this paper are cooperating on a project multipinned-phase mode.