August 2019 BRAS Newsletter
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Spectroscopy of the Candidate Luminous Blue Variable at the Center
A&A manuscript no. ASTRONOMY (will be inserted by hand later) AND Your thesaurus codes are: 06 (08.03.4; 08.05.1; 08.05.3; 08.09.2; 08.13.2; 08.22.3) ASTROPHYSICS Spectroscopy of the candidate luminous blue variable at the center of the ring nebula G79.29+0.46 R.H.M. Voors1,2⋆, T.R. Geballe3, L.B.F.M. Waters4,5, F. Najarro6, and H.J.G.L.M. Lamers1,2 1 Astronomical Institute, University of Utrecht, Princetonplein 5, 3508 TA Utrecht, The Netherlands 2 SRON Laboratory for Space Research, Sorbonnelaan 2, NL-3584 CA Utrecht, The Netherlands 3 Gemini Observatory, 670 N. A’ohoku Place, Hilo, Hawaii 96720, USA 4 Astronomical Institute ’Anton Pannekoek’, University of Amsterdam, Kruislaan 403, NL-1098 SJ Amsterdam, The Nether- lands 5 SRON Laboratory for Space Research, P.O. Box 800, NL-9700 AV Groningen, The Netherlands 6 CSIC Instituto de Estructura de la Materia, Dpto. Fisica Molecular, C/Serrano 121, E-28006 Madrid, Spain Received date: 23 March 2000; accepted date Abstract. We report optical and near-infrared spectra of Luminous Blue Variable (LBV) stage (Conti 1984), these the central star of the radio source G79.29+0.46, a can- stars lose a large amount of mass in a short time interval didate luminous blue variable. The spectra contain nu- (e.g. Chiosi & Maeder 1986). The identifying characteris- merous narrow (FWHM < 100 kms−1) emission lines of tics of an LBV in addition to its blue colors are (1) a mass −5 −1 which the low-lying hydrogen lines are the strongest, and loss rate of (∼ 10 M⊙ yr ), (2) a low wind velocity of resemble spectra of other LBVc’s and B[e] supergiants. -
BRAS Newsletter August 2013
www.brastro.org August 2013 Next meeting Aug 12th 7:00PM at the HRPO Dark Site Observing Dates: Primary on Aug. 3rd, Secondary on Aug. 10th Photo credit: Saturn taken on 20” OGS + Orion Starshoot - Ben Toman 1 What's in this issue: PRESIDENT'S MESSAGE....................................................................................................................3 NOTES FROM THE VICE PRESIDENT ............................................................................................4 MESSAGE FROM THE HRPO …....................................................................................................5 MONTHLY OBSERVING NOTES ....................................................................................................6 OUTREACH CHAIRPERSON’S NOTES .........................................................................................13 MEMBERSHIP APPLICATION .......................................................................................................14 2 PRESIDENT'S MESSAGE Hi Everyone, I hope you’ve been having a great Summer so far and had luck beating the heat as much as possible. The weather sure hasn’t been cooperative for observing, though! First I have a pretty cool announcement. Thanks to the efforts of club member Walt Cooney, there are 5 newly named asteroids in the sky. (53256) Sinitiere - Named for former BRAS Treasurer Bob Sinitiere (74439) Brenden - Named for founding member Craig Brenden (85878) Guzik - Named for LSU professor T. Greg Guzik (101722) Pursell - Named for founding member Wally Pursell -
Discovery of a Pulsar Wind Nebula Candidate in the Cygnus Loop
Discovery of a Pulsar Wind Nebula Candidate in the Cygnus Loop 2 3 S Satoru Katsuda" Hiroshi Tsunemi , Koji Mori , Hiroyuki Uchida" Robert Petre , Shin'ya 1 Yamada , and Thru Tamagawa' ABSTRACT We report on a discovery of a diffuse nebula containing a pointlike source in the southern blowout region of the Cygnus Loop supernova remnant, based on Suzaku and XMM-Newton observations. The X-ray spectra from the nebula and the pointlike source are well represented by an absorbed power-law model with photon indices of 2.2±0.1 and 1.6±0.2, respectively. The photon indices as well as the flux ratio of F nebula/ F po;.,li" ~ 4 lead us to propose that the system is a pulsar wind nebula, although pulsations have not yet been detected. If we attribute its origin to the Cygnus Loop supernova, then the 0.5- 8 keY luminosity of the nebula is computed to be 2.1xlo"' (d/MOpc)2ergss-" where d is the distance to the Loop. This implies a spin-down loss-energy E ~ 2.6 X 1035 (d/MOpc)2ergss-'. The location of the neutron star candidate, ~2° away from the geometric center of the Loop, implies a high transverse velocity of ~ 1850(8/2D ) (d/540pc) (t/lOkyr)- ' kms-" assuming the currently accepted age of the Cygnus Loop. Subject headings: ISM: individual objects (Cygnus Loop) - ISM: supernova remnants - pulsars: general - stars: neutron - stars: winds, outflows - X-rays: ISM 'RlKEN (The Institute of Physical and Chemical Research), 2-1 Hirosawa, Wako, Sailama 351-0198 2Department of EaTth and Space Science, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Thyonaka, Osaka, 60-0043, Japan SDepartment of Applied Physics, Faculty of Engineering, University of Miyazaki, 1-1 Gakuen Klbana-dai Nishi, Miyazaki, 889-2192, Japan ' Department of PhysiCS, Kyoto University, Kitashirakawa-oiwake-clto, Sakyo, Kyoto 606-8502, J apan 'NASA Goddard Space Flight Center, Code 662, Greenbelt MD 20771 - 2 - 1. -
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 -
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. -
SEPTEMBER 2014 OT H E D Ebn V E R S E R V ESEPTEMBERR 2014
THE DENVER OBSERVER SEPTEMBER 2014 OT h e D eBn v e r S E R V ESEPTEMBERR 2014 FROM THE INSIDE LOOKING OUT Calendar Taken on July 25th in San Luis State Park near the Great Sand Dunes in Colorado, Jeff made this image of the Milky Way during an overnight camping stop on the way to Santa Fe, NM. It was taken with a Canon 2............................. First quarter moon 60D camera, an EFS 15-85 lens, using an iOptron SkyTracker. It is a single frame, with no stacking or dark/ 8.......................................... Full moon bias frames, at ISO 1600 for two minutes. Visible in this south-facing photograph is Sagittarius, and the 14............ Aldebaran 1.4˚ south of moon Dark Horse Nebula inside of the Milky Way. He processed the image in Adobe Lightroom. Image © Jeff Tropeano 15............................ Last quarter moon 22........................... Autumnal Equinox 24........................................ New moon Inside the Observer SEPTEMBER SKIES by Dennis Cochran ygnus the Swan dives onto center stage this other famous deep-sky object is the Veil Nebula, President’s Message....................... 2 C month, almost overhead. Leading the descent also known as the Cygnus Loop, a supernova rem- is the nose of the swan, the star known as nant so large that its separate arcs were known Society Directory.......................... 2 Albireo, a beautiful multi-colored double. One and named before it was found to be one wide Schedule of Events......................... 2 wonders if Albireo has any planets from which to wisp that came out of a single star. The Veil is see the pair up-close. -
Sky Notes by Neil Bone 2005 August & September
Sky notes by Neil Bone 2005 August & September below Castor and Pollux. Mercury is soon ing June and July, it is still quite possible that Sun and Moon lost from view again, arriving at superior con- noctilucent clouds (NLC) could be seen into junction beyond the Sun on September 18. early August, particularly by observers at The Sun continues its southerly progress along Venus continues its rather unfavourable more northerly locations. Quite how late into the ecliptic, reaching the autumnal equinox showing as an ‘Evening Star’. Although it August NLC can be seen remains to be deter- position at 22h 23m Universal Time (UT = pulls out to over 40° elongation east of the mined: there have been suggestions that the GMT; BST minus 1 hour) on September 22. Sun during September, Venus is also heading visibility period has become longer in recent At that precise time, the centre of the solar southwards, and as a result its setting-time years. Observational reports will be welcomed disk is positioned at the intersection between after the Sun remains much the same − barely by the Aurora Section. the celestial equator and the ecliptic, the latter an hour − during this interval. Although bright While declining sunspot activity makes great circle on the sky being inclined by 23.5° at magnitude −4, Venus will be quite tricky major aurorae extending to lower latitudes to the former. Calendrical autumn begins at the to catch in the early twilight: viewing cir- less likely, the appearance of coronal holes equinox, but amateur astronomers might more cumstances don’t really improve until the in the latter parts of the cycle does bring the readily follow meteorological timing, wherein closing weeks of 2005. -
Nightwatch Club Events Calendar President's Message
Henry Wadsworth Longfellow Henry Wadsworth Thewithfilled skyby day. is stars, invisible Volume 32 Number 06 nightwatch June 2012 President's Message Club Events Calendar Busy days right now, both in the heavens and here on Earth. June 8 - General Meeting – Speaker Robert Stephens - I've heard lots of good reports of people successfully viewing the “A Journey Through the Asteroid Belt” eclipse on May 20. My own eclipse trip to Page, Arizona, was a June 16 - Star Party - White Mountain smashing success. The lunar eclipse early in the morning on June 22 - Star Party - Cottonwood Springs - joint with June 4 was clouded out, at least here in Claremont. By the time Palm Springs Braille Institute you read this, the transit of Venus across the face of the sun on June 5 will already have happened. I hope you got a chance to July 2 - School Star Party - Colony High School, Ontario see it—it won't happen again until 2117. July 5 - Board Meeting, 6:15 We also have some great club events coming up. Our speaker July 13 - General Meeting for the June 8 general meeting is Robert Stephens July 21 – Star Party – Cottonwood Springs (http://planetarysciences.org/stephens.html), who will give us “A July 24 - Ontario Library Main Branch - Dark to 9pm Journey Through the Asteroid Belt”. On June 16 we'll have a star July 25 – Star Party – Orange County Braille Institute, party at White Mountain. My annual curse has struck again—I'll Anaheim be in New York looking at fossils instead of on White Mountain looking at stars, but I hope you all have fun without me. -
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). -
Eagle Nebula Star Formation Region
Eagle Nebula Star Formation Region AST 303: Chapter 17 1 The Formation of Stars (2) • A cloud of gas and dust must collapse if stars are to be formed. • The self-gravity of the cloud will tend to cause it to collapse. • Radiation pressure from nearby hot stars may do the same. • The passage of a shock wave from a nearby supernova blast or some other source (such as galactic shock waves) may do the same. – Note: The “sonic boom” of a jet plane is an example of a shock wave. • When two clouds collide, they may cause each other to collapse. AST 303: Chapter 17 2 Trifid Nebula AST 303: Chapter 17 3 Trifid Nebula Stellar Nursery Revealed AST 303: Chapter 17 4 Young Starburst Cluster Emerges from Cloud AST 303: Chapter 17 5 The Formation of Stars (3) • The gas in the collapsing cloud probably becomes turbulent. • This would tend to fragment the collapsing gas, producing condensations that would be the nuclei of new stars. • There is abundant evidence that shows that the stars in a cluster are all about the same age. For a young cluster, many stars have not yet reached the main sequence: ! Isochron Luminosity "Temperature AST 303: Chapter 17 6 The Formation of Stars (4) • The evolutionary paths of young stars on the H-R diagram look like this. Note the T Tauri stars, long thought to be young stars. • Theory says that these stars use convection as the main method of transporting energy to their surfaces. ! T Tauri Stars Luminosity "Temperature AST 303: Chapter 17 7 The Search for Stellar Precursors • Astronomers have long been fascinated by very dark, dense regions seen outlined against bright gas, called globules. -
Hard X-Ray Emission Clumps in the Γ-Cygni Supernova Remnant: the an INTEGRAL-ISGRI View To
A&A 427, L21–L24 (2004) Astronomy DOI: 10.1051/0004-6361:200400089 & c ESO 2004 Astrophysics Editor Hard X-ray emission clumps in the γ-Cygni supernova remnant: the An INTEGRAL-ISGRI view to A. M. Bykov1, A. M. Krassilchtchikov1 , Yu. A. Uvarov1,H.Bloemen2,R.A.Chevalier3, M. Yu. Gustov1, W. Hermsen2,F.Lebrun4,T.A.Lozinskaya5,G.Rauw6,T.V.Smirnova7, S. J. Sturner8, J.-P. Swings6, R. Terrier4, and I. N. Toptygin1 Letter 1 A. F. Ioffe Institute for Physics and Technology, 26 Polytechnicheskaia, 194021 St. Petersburg, Russia e-mail: [email protected] 2 SRON National Institute for Space Research, Sorbonnelaan 2, 3584 CA Utrecht, The Netherlands 3 Department of Astronomy, University of Virginia, PO Box 3818, Charlottesville, VA 22903, USA 4 CEA – Saclay, DSM/DAPNIA/Service d’Astrophysique, 91191 Gif-sur-Yvette Cedex, France 5 Sternberg Astronomical Institute, Moscow State University, 13 Universitetskij, 119899 Moscow, Russia 6 Institut d’Astrophysique et de Géophysique, Université de Liège, Allée du 6 Août 17, Bât. B5c, 4000 Liège, Belgium 7 Astro Space Center of the Lebedev Physics Institute, 84/32 Profsoyuznaia, 117810 Moscow, Russia 8 NASA Goddard Space Flight Center, Code 661, Greenbelt, MD 20771, USA Received 22 September 2004 / Accepted 9 October 2004 Abstract. Spatially resolved images of the galactic supernova remnant G78.2+2.1 (γ-Cygni) in hard X-ray energy bands from 25 keV to 120 keV are obtained with the IBIS-ISGRI imager aboard the International Gamma-Ray Astrophysics Laboratory INTEGRAL. The images are dominated by localized clumps of about ten arcmin in size. -
International Astronomical Union Commission 42 BIBLIOGRAPHY of CLOSE BINARIES No. 93
International Astronomical Union Commission 42 BIBLIOGRAPHY OF CLOSE BINARIES No. 93 Editor-in-Chief: C.D. Scarfe Editors: H. Drechsel D.R. Faulkner E. Kilpio E. Lapasset Y. Nakamura P.G. Niarchos R.G. Samec E. Tamajo W. Van Hamme M. Wolf Material published by September 15, 2011 BCB issues are available via URL: http://www.konkoly.hu/IAUC42/bcb.html, http://www.sternwarte.uni-erlangen.de/pub/bcb or http://www.astro.uvic.ca/∼robb/bcb/comm42bcb.html The bibliographical entries for Individual Stars and Collections of Data, as well as a few General entries, are categorized according to the following coding scheme. Data from archives or databases, or previously published, are identified with an asterisk. The observation codes in the first four groups may be followed by one of the following wavelength codes. g. γ-ray. i. infrared. m. microwave. o. optical r. radio u. ultraviolet x. x-ray 1. Photometric data a. CCD b. Photoelectric c. Photographic d. Visual 2. Spectroscopic data a. Radial velocities b. Spectral classification c. Line identification d. Spectrophotometry 3. Polarimetry a. Broad-band b. Spectropolarimetry 4. Astrometry a. Positions and proper motions b. Relative positions only c. Interferometry 5. Derived results a. Times of minima b. New or improved ephemeris, period variations c. Parameters derivable from light curves d. Elements derivable from velocity curves e. Absolute dimensions, masses f. Apsidal motion and structure constants g. Physical properties of stellar atmospheres h. Chemical abundances i. Accretion disks and accretion phenomena j. Mass loss and mass exchange k. Rotational velocities 6. Catalogues, discoveries, charts a.