Issue 32, June 2006
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FY08 Technical Papers by GSMTPO Staff
AURA/NOAO ANNUAL REPORT FY 2008 Submitted to the National Science Foundation July 23, 2008 Revised as Complete and Submitted December 23, 2008 NGC 660, ~13 Mpc from the Earth, is a peculiar, polar ring galaxy that resulted from two galaxies colliding. It consists of a nearly edge-on disk and a strongly warped outer disk. Image Credit: T.A. Rector/University of Alaska, Anchorage NATIONAL OPTICAL ASTRONOMY OBSERVATORY NOAO ANNUAL REPORT FY 2008 Submitted to the National Science Foundation December 23, 2008 TABLE OF CONTENTS EXECUTIVE SUMMARY ............................................................................................................................. 1 1 SCIENTIFIC ACTIVITIES AND FINDINGS ..................................................................................... 2 1.1 Cerro Tololo Inter-American Observatory...................................................................................... 2 The Once and Future Supernova η Carinae...................................................................................................... 2 A Stellar Merger and a Missing White Dwarf.................................................................................................. 3 Imaging the COSMOS...................................................................................................................................... 3 The Hubble Constant from a Gravitational Lens.............................................................................................. 4 A New Dwarf Nova in the Period Gap............................................................................................................ -
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A&A 454, 527–536 (2006) Astronomy DOI: 10.1051/0004-6361:20053468 & c ESO 2006 Astrophysics A search for photometric variability of hydrogen-deficient planetary-nebula nuclei, J. M. González Pérez1,2, J.-E. Solheim2,3, and R. Kamben2 1 Instituto de Astrofísica de Canarias, 38200 La Laguna, Tenerife, Spain e-mail: [email protected] 2 Institut of Physics, University of Tromsø, 9037 Tromsø, Norway 3 Institut of Theoretical Astrophysics, University of Oslo, PO box 1029 Blindern, 0315 Oslo, Norway Received 18 May 2005 / Accepted 9 March 2006 ABSTRACT Aims. We searched for photometric variability in a sample of hot, hydrogen-deficient planetary nebula nuclei (PNNi) with “PG 1159” or “O VI” spectral type, most of them embedded in a bipolar or elliptical planetary nebula envelope (PNe). These characteristics may indicate the presence of a hidden close companion and an evolution affected by episodes of interaction between them. Methods. We obtained time-series photometry from a sample of 11 candidates using the Nordic Optical Telescope (NOT) with the Andalucía Faint Object Spectrograph and Camera (ALFOSC), modified with our own control software to be able to observe in a high- speed multi-windowing mode. The data were reduced on-line with the real time photometry (RTP) code, which allowed us to detect periodic variable stars with small amplitudes from CCD data in real time. We studied the properties of the observed modulation fre- quencies to investigate their nature. Results. We report the first detection of low-amplitude pulsations in the PNNi VV 47, NGC 6852, and Jn 1. In addition, we investi- gated the photometric variability of NGC 246. -
Planetary Nebulae
Planetary Nebulae A planetary nebula is a kind of emission nebula consisting of an expanding, glowing shell of ionized gas ejected from old red giant stars late in their lives. The term "planetary nebula" is a misnomer that originated in the 1780s with astronomer William Herschel because when viewed through his telescope, these objects appeared to him to resemble the rounded shapes of planets. Herschel's name for these objects was popularly adopted and has not been changed. They are a relatively short-lived phenomenon, lasting a few tens of thousands of years, compared to a typical stellar lifetime of several billion years. The mechanism for formation of most planetary nebulae is thought to be the following: at the end of the star's life, during the red giant phase, the outer layers of the star are expelled by strong stellar winds. Eventually, after most of the red giant's atmosphere is dissipated, the exposed hot, luminous core emits ultraviolet radiation to ionize the ejected outer layers of the star. Absorbed ultraviolet light energizes the shell of nebulous gas around the central star, appearing as a bright colored planetary nebula at several discrete visible wavelengths. Planetary nebulae may play a crucial role in the chemical evolution of the Milky Way, returning material to the interstellar medium from stars where elements, the products of nucleosynthesis (such as carbon, nitrogen, oxygen and neon), have been created. Planetary nebulae are also observed in more distant galaxies, yielding useful information about their chemical abundances. In recent years, Hubble Space Telescope images have revealed many planetary nebulae to have extremely complex and varied morphologies. -
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. -
The Agb Newsletter
THE AGB NEWSLETTER An electronic publication dedicated to Asymptotic Giant Branch stars and related phenomena Official publication of the IAU Working Group on Abundances in Red Giants No. 165 — 1 April 2011 http://www.astro.keele.ac.uk/AGBnews Editors: Jacco van Loon and Albert Zijlstra Editorial Dear Colleagues, It is our pleasure to present you the 165th issue of the AGB Newsletter. Lots of nucleosynthesis work, pulsating stars, binaries, and AGB stars in stellar systems from globulars and the Bulge to Local Group galaxies and farther afield. Congratulations to Val´erio Ribeiro, who has just obtained his Philospher’s Degree. It’s great then to see that there are opportunitites for postdoctoral research, such as the one advertised by the group in Uppsala. Don’t miss the announcement of the very interesting workshop in wonderful Warsaw this Summer. Stefan Uttenthaler, back in Vienna, offered the following reaction to last month’s Food for Thought: ”Certainly, the PN population will not be fully representative of the underlying AGB population. Most likely not every AGB star will evolve into a PN, and also the binarity properties (incl. planets) of the population will have an impact on the evolution from the AGB to the PN phase. In fact, just in the previous issue of the Newsletter, De Marco & Soker note that the presence of a companion will alter the PN life time, and that only one quarter of all AGB stars will make a PN. Now concerning the Bulge my opinion is that in the absence of evidence that the PNe are not representative for the underlying AGB population (i.e. -
Stats2010 E Final.Pdf
Imprint Publisher: Max-Planck-Institut für extraterrestrische Physik Editors and Layout: W. Collmar und J. Zanker-Smith Personnel 1 PERSONNEL 2010 Directors Min. Dir. J. Meyer, Section Head, Federal Ministry of Prof. Dr. R. Bender, Optical and Interpretative Astronomy, Economics and Technology also Professorship for Astronomy/Astrophysics at the Prof. Dr. E. Rohkamm, Thyssen Krupp AG, Düsseldorf Ludwig-Maximilians-University Munich Prof. Dr. R. Genzel, Infrared- and Submillimeter- Scientifi c Advisory Board Astronomy, also Prof. of Physics, University of California, Prof. Dr. R. Davies, Oxford University (UK) Berkeley (USA) (Managing Director) Prof. Dr. R. Ellis, CALTECH (USA) Prof. Dr. Kirpal Nandra, High-Energy Astrophysics Dr. N. Gehrels, NASA/GSFC (USA) Prof. Dr. G. Morfi ll, Theory, Non-linear Dynamics, Complex Prof. Dr. F. Harrison, CALTECH (USA) Plasmas Prof. Dr. O. Havnes, University of Tromsø (Norway) Prof. Dr. G. Haerendel (emeritus) Prof. Dr. P. Léna, Université Paris VII (France) Prof. Dr. R. Lüst (emeritus) Prof. Dr. R. McCray, University of Colorado (USA), Prof. Dr. K. Pinkau (emeritus) Chair of Board Prof. Dr. J. Trümper (emeritus) Prof. Dr. M. Salvati, Osservatorio Astrofi sico di Arcetri (Italy) Junior Research Groups and Minerva Fellows Dr. N.M. Förster Schreiber Humboldt Awardee Dr. S. Khochfar Prof. Dr. P. Henry, University of Hawaii (USA) Prof. Dr. H. Netzer, Tel Aviv University (Israel) MPG Fellow Prof. Dr. V. Tsytovich, Russian Academy of Sciences, Prof. Dr. A. Burkert (LMU) Moscow (Russia) Manager’s Assistant Prof. S. Veilleux, University of Maryland (USA) Dr. H. Scheingraber A. v. Humboldt Fellows Scientifi c Secretary Prof. Dr. D. Jaffe, University of Texas (USA) Dr. -
A Blast Wave from the 1843 Eruption of Eta Carinae
1 A Blast Wave from the 1843 Eruption of Eta Carinae Nathan Smith* *Astronomy Department, University of California, 601 Campbell Hall, Berkeley, CA 94720-3411 Very massive stars shed much of their mass in violent precursor eruptions [1] as luminous blue variables (LBVs) [2] before reaching their most likely end as supernovae, but the cause of LBV eruptions is unknown. The 19th century eruption of Eta Carinae, the prototype of these events [3], ejected about 12 solar masses at speeds of 650 km/s, with a kinetic energy of almost 1050ergs[4]. Some faster material with speeds up to 1000-2000 km/s had previously been reported [5,6,7,8] but its full distribution was unknown. Here I report observations of much faster material with speeds up to 3500-6000 km/s, reaching farther from the star than the fastest material in earlier reports [5]. This fast material roughly doubles the kinetic energy of the 19th century event, and suggests that it released a blast wave now propagating ahead of the massive ejecta. Thus, Eta Carinae’s outer shell now mimics a low-energy supernova remnant. The eruption has usually been discussed in terms of an extreme wind driven by the star’s luminosity [2,3,9,10], but fast material reported here suggests that it was powered by a deep-seated explosion rivalling a supernova, perhaps triggered by the pulsational pair instability[11]. This may alter interpretations of similar events seen in other galaxies. Eta Carinae [3] is the most luminous and the best studied among LBVs [1,2]. -
NASA's Goddard Space Flight Center Laboratory for Astronomy & Solar Physics Greenbelt, Maryland, 20771
NASA’s Goddard Space Flight Center Laboratory for Astronomy & Solar Physics Greenbelt, Maryland, 20771 The following report covers the period from Septem- istrator announced the cancellation of the next servicing ber 2003 through September 2004. mission (SM4) to the Hubble Space Telescope (HST), citing safety concerns about sending the Shuttle into an 1 INTRODUCTION orbit that did not have a “safe haven” (namely, the Inter- The Laboratory for Astronomy & Solar Physics national Space Station). Subsequently, the Administra- (LASP) is a Division of the Space Sciences Directorate tor authorized GSFC to begin study of a robotic repair at NASA’s Goddard Space Flight Center (GSFC). Mem- of HST, which would add new batteries, gyroscopes, and bers of LASP conduct a broad program of observational install both of the new instruments intended for installa- and theoretical scientific research. Observations are car- tion on SM4 – the Cosmic Origins Spectrograph (COS) ried out from space-based observatories, balloons, and and the Wide Field Camera 3 (WFC3). An intensive ground-based telescopes at wavelengths extending from engineering effort in the HST Project at Goddard is cur- the EUV to the sub-millimeter. Research projects cover rently underway to determine if this robotic repair is the fields of solar and stellar astrophysics, extrasolar technically possible within the allowed time-fame (be- planets, the interstellar and intergalactic medium, ac- fore the HST batteries die). WFC3 has completed a tive galactic nuclei, and the evolution of structure in the successful initial thermal vacuum test at Goddard under universe. the leadership of Instrument Scientist Randy Kimble. Studies of the sun are carried out in the gamma- However, on a decidedly sad note for LASP, the Space ray, x-ray, EUV/UV and visible portions of the spec- Telescope Imaging Spectrograph (STIS; Woodgate, PI), trum from space and the ground. -
Planetary Nebulae: Exposing the Top Polluters of the ISM
The Evolving ISM in the Milky Way & Nearby Galaxies Planetary Nebulae: Exposing the Top Polluters of the ISM Joseph L. Hora1, Massimo Marengo1, Howard A. Smith1, Luciano Cerrigone1, William B. Latter2 ABSTRACT The high mass loss rates of stars in their asymptotic giant branch (AGB) stage of evolution is one of the most important pathways for mass return from stars to the ISM. In the planetary nebulae (PNe) phase, the ejected material is illuminated and can be altered by the UV radiation from the central star. PNe therefore play a significant role in the ISM recycling process and in changing the environment around them. We show some highlights of the results of observations that have been carried out using the Spitzer instruments to study the gas and dust emission from PNe in the Milky Way and nearby galaxies. Spitzer is especially sensitive to the cool dust and molecules in the PNe shell and halos. We present new results from our program on Galactic PNe, including IRAC and IRS observations of NGC 6720 in the ring and halo of that nebula. Subject headings: galaxies: ISM | infrared: galaxies | infrared: ISM | ISM: dust, extinction | ISM: structure 1. Introduction A key link in the recycling of material to the Interstellar Medium (ISM) is the phase of stellar evolution from Asymptotic Giant Branch (AGB) to white dwarf star. When stars are on the AGB, they begin to lose mass at a prodigious rate. The stars on the AGB are relatively cool, and their atmospheres are a fertile environment for the formation of dust and molecules. -
The Perek-Kohoutek Catalogue of Planetary Nebulae
Perek- Right Catalog Other Declination Kohoutek ascension The Perek-Kohoutek number designation (2000.0) number (2000.0) Catalogue of 1 119+06.1 A 1 0h12.9m 69°11' 2 120+09.1 NGC 40 0h13.0m 72°32' Planetary Nebulae 3 118–08.1 Vy 1–1 0h18.7m 53°53' 4 119+00.1 BV 1 0h19.9m 62°59' Data is from Catalogue of Galactic Planetary 5 119–06.1 Hu 1–1 0h28.3m 55°58' Nebulae, updated version 2000, by L. Kohoutek, 6 120–05.1 Sh 2–176 0h31.8m 57°23' Hamburg-Berfedorf, 2001. 7 108–76.1 BOBN 1 0h37.2m –13°43' 8 121+03.1 We 1–1 0h38.9m 66°23' 9 121+00.1 BV 2 0h40.3m 62°51' 10 122–04.1 A 2 0h45.6m 57°57' 11 118–74.1 NGC 246 0h47.0m –11°53' 12 125–47.1 PHL 932 0h59.9m 15°44' 13 124–07.1 WeSb 1 1h00.9m 55°04' 14 124+02.1 KLSS 2–7 1h02.4m 65°46' 15 124+10.1 EL 0103+73 1h07.1m 73°33' 16 126+03.1 K 3–90 1h24.9m 65°39' 17 128–04.1 S 22 1h30.5m 58°24' 18 130–11.1 M 1–1 1h37.3m 50°28' 19 129–05.1 KLSS 2–8 1h40.1m 56°35' 20 130–10.1 NGC 650–1 1h42.4m 51°34' 21 129–02.1 We 2–5 1h42.6m 60°10' 22 131–05.1 BV 3 1h53.0m 56°25' 23 130+01.1 IC 1747 1h57.6m 63°20' 24 129+04.1 K 3–91 1h58.6m 66°34' 25 148–48.1 GR 0155+10 1h58.0m 10°57' 26 133–08.1 M 1–2 1h58.8m 52°54' 27 130+03.1 K 3–92 2h03.7m 64°57' 28 131+02.1 A 3 2h12.1m 64°09' 29 132+04.1 K 3–93 2h26.5m 65°47' 30 144–15.1 A 4 2h45.4m 42°34' 31 141–07.1 A 5 2h52.3m 50°36' 32 136+04.1 A 6 2h58.7m 64°30' 33 255–59.1 Lo 1 2h57.0m –44°10' 34 136+05.1 HEFE 1 3h03.8m 64°54' 35 138+02.1 IC 289 3h10.3m 61°19' 36 138+04.1 HtDe 2 3h11.0m 62°48' 37 147–09.1 HtWe 3 3h16.6m 46°54' 38 149–09.1 HtDe 3 3h27.2m 45°24' 39 220–53.1 NGC -
OCTOBER 2013 OT H E D Ebn V E R S E R V EOCTOBERR 2013
THE DENVER OBSERVER OCTOBER 2013 OT h e D eBn v e r S E R V EOCTOBERR 2013 P H O T O O P P S G A L O R E — G E A R U P ! ! SISTER GALAXY—THE ANDROMEDA GALAXY (M31 OR NGC 224) The Andromeda galaxy is one of the closest galaxies to our own. At only 2.5 million light-years away, it Calendar spans about 170 arc-minutes of sky which is over three times the diameter of the moon! Although that distance in light years equates to 393,121,310,400,000,000 km, it is still close enough to see in incredi- 4.......................................... New moon ble detail. Because of its close proximity, Andromeda is fairly easy to image because it is bright enough to capture in short exposures. The images that comprise this image were taken on November 1, 2008 at 11............................ First quarter moon the CSAS site near Gardner, CO. with a Canon EOS Digital Rebel XTi using a Canon 200 mm f/4L lens 18......................................... Full moon riding atop a Meade 10-inch LX200GPS on an equatorial wedge. There are a total of 13 60-second im- ages stacked together to render this image. Stacking and editing was accomplished using Images Plus. 26........................... Last quarter moon Image © Scott Leach Inside the Observer OCTOBER SKIES by Dennis Cochran he Canadian astronomy magazine Sky News (from comet Giacobini-Zinner) on the 8th, then on President’s Message......................... 2 T informs us that on October 11, there will be the 10th we’ll see the Southern Taurids (from comet three—count ’em—three moon shadows on Enke). -
The Binarity of Eta Carinae Revealed from Photoionization Modeling of The
The Binarity of Eta Carinae Revealed from Photoionization Modeling of the Spectral Variability of the Weigelt Blobs B and D 1 Short title: Eta Carinae Binarity E. Verner2,3, F. Bruhweiler2,3, and T. Gull3 [email protected], [email protected], and [email protected] 1 Based on observations made with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555 2 Institute for Astrophysics and Computational Science, Department of Physics, Catholic University of America, 200 Hannan Hall, Washington, DC 20064 3 Laboratory of Astronomy and Solar Physics, NASA Goddard Space, Flight Center, Greenbelt, MD 20771 Abstract We focus on two Hubble Space Telescope/Space Telescope Imaging Spectrograph (HST/STIS) spectra of the Weigelt Blobs B&D, extending from 1640 to 10400Å; one recorded during the 1998 minimum (March 1998) and the other recorded in February 1999, early in the following broad maximum. The spatially-resolved spectra suggest two distinct ionization regions. One structure is the permanently low ionization cores of the Weigelt Blobs, B&D, located several hundred AU from the ionizing source. Their spectra are dominated by emission from H I, [N II], Fe II, [Fe II], Ni II, [Ni II], Cr II and Ti II. The second region, relatively diffuse in character and located between the ionizing source and the Weigelt Blobs, is more highly ionized with emission from [Fe III], [Fe IV], N III], [Ne III], [Ar III], [Si III], [S III] and He I.