A Norma Scorpius
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The Richness of Compact Radio Sources in NGC 6334D to F S.-N
Astronomy & Astrophysics manuscript no. main c ESO 2021 June 22, 2021 The richness of compact radio sources in NGC 6334D to F S.-N. X. Medina1, S. A. Dzib1, M. Tapia2, L. F. Rodríguez3, and L. Loinard3;4 1 Max-Planck-Institut für Radioastronomie, Auf dem Hügel 69, D-53121 Bonn, Germany 2 Instituto de Astronomía, Universidad Nacional Autónoma de México, Ensenada, B. C., CP 22830, Mexico 3 Instituto de Radioastronomía y Astrofísica, Universidad Nacional Autónoma de México, Morelia 58089, Mexico 4 Instituto de Astronomía, Universidad Nacional Autónoma de México, Apartado Postal 70-264, CdMx C.P. 04510, Mexico e-mail: smedina, sdzib, @mpifr-bonn.mpg.de; [email protected]; l.rodriguez, and l.loinard, @crya.unam.mx Received 2017; ABSTRACT Context. The presence and properties of compact radio sources embedded in massive star-forming regions can reveal important physical properties about these regions and the processes occurring within them. The NGC 6334 complex, a massive star-forming region, has been studied extensively. Nevertheless, none of these studies has focused in its content in compact radio sources. Aims. Our goal here is to report on a systematic census of the compact radio sources toward NGC 6334, and their characteristics. This will be used to try and define their very nature. Methods. We use VLA C band (4–8 GHz) archive data with 000.36 (500 AU) of spatial resolution and noise level of 50 µJy bm−1 to carry out a systematic search for compact radio sources within NGC 6334. We also search for infrared counterparts to provide some constraints on the nature of the detected radio sources. -
Planetary Nebula
How Far Away Is It – Planetary Nebula Planetary Nebula {Abstract – In this segment of our “How far away is it” video book, we cover Planetary Nebula. We begin by introducing astrophotography and how it adds to what we can see through a telescope with our eyes. We use NGC 2818 to illustrate how this works. This continues into the modern use of Charge-Coupled Devices and how they work. We use the planetary nebula MyCn18 to illustrate the use of color filters to identify elements in the nebula. We then show a clip illustrating the end-of-life explosion that creates objects like the Helix Planetary Nebula (NGC 7293), and show how it would fill the space between our Sun and our nearest star, Proxima Centauri. Then, we use the Cat’s Eye Nebula (NGC 6543) to illustrate expansion parallax. As a fundamental component for calculating expansion parallax, we also illustrate the Doppler Effect and how we measure it via spectral line red and blue shifts. We continue with a tour of the most beautiful planetary nebula photographed by Hubble. These include: the Dumbbell Nebula, NGC 5189, Ring Nebula, Retina Nebula, Red Rectangle, Ant Nebula, Butterfly Nebula, , Kohoutek 4- 55, Eskimo Nebula, NGC 6751, SuWt 2, Starfish, NGC 5315, NGC 5307, Little Ghost Nebula, NGC 2440, IC 4593, Red Spider, Boomerang, Twin Jet, Calabash, Gomez’s Hamburger and others culminating with a dive into the Necklace Nebula. We conclude by noting that this will be the most likely end for our Sun, but not for billions of years to come, and we update the Cosmic Distance Ladder with the new ‘Expansion Parallax’ rung developed in this segment.} Introduction [Music @00:00 Bizet, Georges: Entracte to Act III from “Carman”; Orchestre National de France / Seiji Ozawa, 1984; from the album “The most relaxing classical album in the world…ever!”] Planetary Nebulae represent some of the most beautiful objects in the Milky Way. -
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Arxiv:2012.09981V1 [Astro-Ph.SR] 17 Dec 2020 2 O
Contrib. Astron. Obs. Skalnat´ePleso XX, 1 { 20, (2020) DOI: to be assigned later Flare stars in nearby Galactic open clusters based on TESS data Olga Maryeva1;2, Kamil Bicz3, Caiyun Xia4, Martina Baratella5, Patrik Cechvalaˇ 6 and Krisztian Vida7 1 Astronomical Institute of the Czech Academy of Sciences 251 65 Ondˇrejov,The Czech Republic(E-mail: [email protected]) 2 Lomonosov Moscow State University, Sternberg Astronomical Institute, Universitetsky pr. 13, 119234, Moscow, Russia 3 Astronomical Institute, University of Wroc law, Kopernika 11, 51-622 Wroc law, Poland 4 Department of Theoretical Physics and Astrophysics, Faculty of Science, Masaryk University, Kotl´aˇrsk´a2, 611 37 Brno, Czech Republic 5 Dipartimento di Fisica e Astronomia Galileo Galilei, Vicolo Osservatorio 3, 35122, Padova, Italy, (E-mail: [email protected]) 6 Department of Astronomy, Physics of the Earth and Meteorology, Faculty of Mathematics, Physics and Informatics, Comenius University in Bratislava, Mlynsk´adolina F-2, 842 48 Bratislava, Slovakia 7 Konkoly Observatory, Research Centre for Astronomy and Earth Sciences, H-1121 Budapest, Konkoly Thege Mikl´os´ut15-17, Hungary Received: September ??, 2020; Accepted: ????????? ??, 2020 Abstract. The study is devoted to search for flare stars among confirmed members of Galactic open clusters using high-cadence photometry from TESS mission. We analyzed 957 high-cadence light curves of members from 136 open clusters. As a result, 56 flare stars were found, among them 8 hot B-A type ob- jects. Of all flares, 63 % were detected in sample of cool stars (Teff < 5000 K), and 29 % { in stars of spectral type G, while 23 % in K-type stars and ap- proximately 34% of all detected flares are in M-type stars. -
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. -
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). -
The Complete ISO Spectrum of NGC 6302?
A&A 372, 165–172 (2001) Astronomy DOI: 10.1051/0004-6361:20010465 & c ESO 2001 Astrophysics The complete ISO spectrum of NGC 6302? F. J. Molster1,2,T.L.Lim3,R.J.Sylvester4,L.B.F.M.Waters1,5,M.J.Barlow4,D.A.Beintema6, M. Cohen7,P.Cox8, and B. Schmitt9 1 Astronomical Institute “Anton Pannekoek”, University of Amsterdam, Kruislaan 403, 1098 SJ Amsterdam, The Netherlands 2 School of Materials Science and Engineering, Georgia Tech, Atlanta, GA 30332-0245, USA 3 Space Science Department, Rutherford Appleton Laboratory, Chilton, Didcot OX11 0QX, UK 4 Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT, UK 5 Instituut voor Sterrenkunde, K.U. Leuven, Celestijnenlaan 200B, 3001 Heverlee, Belgium 6 SRON Space Research Laboratory, PO Box 800, 9700 AV Groningen, The Netherlands 7 Radio Astronomy Laboratory, 601 Campbell Hall, University of California, Berkeley, CA 94720, USA 8 Institut d’Astrophysique Spatiale, Bˆat. 121, Universit´e de Paris XI, 91405 Orsay Cedex, France 9 Laboratoire de Planetologie de Grenoble, Universite J. Fourier – CNRS, Bˆat. D de Physique, BP 53, 38041 Grenoble Cedex 9, France Received 12 October 1999 / Accepted 22 March 2001 Abstract. We present the combined Infrared Space Observatory Short-Wavelength Spectrometer and Long- Wavelength Spectrometer 2.4–197 µm spectrum of the Planetary Nebula NGC 6302 which contains in addition to strong atomic lines, a series of emission features due to solid state components. The broad wavelength coverage enables us to more accurately identify and determine the properties of both oxygen- and carbon-rich circumstellar dust. A simple model fit was made to determine the abundance and typical temperature of the amorphous silicates, enstatite and forsterite. -
Spitzer Observations of Planetary Nebulae
Planetary Nebulae: An Eye to the Future Proceedings IAU Symposium No. 283, 2011 c 2011 International Astronomical Union A. Manchado, L. Stanghellini, & D. Sch¨onberner, eds. DOI: 00.0000/X000000000000000X Spitzer Observations of Planetary Nebulae You-Hua Chu Department of Astronomy, University of Illinois, 1002 West Green Street, Urbana, Illinois, 61801, USA email: [email protected] Abstract. The Spitzer Space Telescope has three science instruments (IRAC, MIPS, and IRS) that can take images at 3.6, 4.5, 5.8, 8.0, 24, 70, and 160 µm, spectra over 5–38 µm, and spectral energy distribution over 52–100 µm. The Spitzer archive contains targeted imaging observations for more than 100 PNe. Spitzer legacy surveys, particularly the GLIMPSE survey of the Galactic plane, contain additional serendipitous imaging observations of PNe. Spitzer imaging and spectroscopic observations of PNe allow us to investigate atomic/molecular line emission and dust continuum from the nebulae as well as circumstellar dust disks around the central stars. Highlights of Spitzer observations of PNe are reviewed in this paper. 1. Spitzer Space Telescope The Spitzer Space Telescope (Werner et al. 2004), one of the four NASA’s Great Observatories, is a 0.85 meter diameter, f/12 infrared (IR) telescope launched on August 25, 2003. It has an Earth-trailing heliocentric orbit so that the telescope is kept away from the Earth’s heat and can be cooled more efficiently. Spitzer has three science instruments: (1) The Infrared Array Camera (IRAC; Fazio et al. 2004) has four detectors that take images at 3.6, 4.5, 5.8, and 8.0 µm, respectively. -
The Hubble-Type Outflows from the High-Excitation, Polypolar Planetary Nebula Ngc 6302 J
The Astronomical Journal, 130:2303–2311, 2005 November # 2005. The American Astronomical Society. All rights reserved. Printed in U.S.A. THE HUBBLE-TYPE OUTFLOWS FROM THE HIGH-EXCITATION, POLYPOLAR PLANETARY NEBULA NGC 6302 J. Meaburn, J. A. Lo´pez, and W. Steffen Instituto de Astrono´mia, Universidad Nacional Auto´noma de Me´xico, Campus Ensenada, Apartado Postal 877, 22800 Ensenada, Mexico and M. F. Graham and A. J. Holloway Jodrell Bank Observatory, University of Manchester, Macclesfield SK11 9DL, UK Received 2005 July 8; accepted 2005 July 26 ABSTRACT Spatially resolved profiles of the H and [N ii] lines have been obtained at unprecedented signal-to-noise ratios over the outflowing lobes of the high-excitation, polypolar planetary nebula NGC 6302. A deep image in the light of [N ii] k6584 was also obtained of the extremities of the prominent northwestern lobe. The Manchester Echelle Spectrometer combined with the 2.1 m San Pedro Martir telescope (Mexico) was used for these observations. First, À1 an accurate value of the systemic heliocentric radial velocity of Vsys ¼29:8 Æ 1kms has been established. Also, from ‘‘velocity ellipses’’ across its diameter from previous observations, the parallel-sided northwestern lobe is shown to have a circular section with a tilt of its axis to the plane of the sky of 12N8. With this starting point the position-velocity arrays of profiles have been very closely simulated, using the SHAPE code, with Hubble-type outflows. The faint extremities of the northwestern outflow are shown to be expanding at 600 km sÀ1. The prominent lobes of NGC 6302 have then been generated in an eruptive event with a dynamical age of 1900 yr for an expansion proper-motion distance of 1:04 Æ 0:16 kpc, as measured here by comparing a 1956 image with one taken in 2002. -
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 -
The Distribution of Molecular Hydrogen in Planetary Nebulae
THE DISTRIBUTION OF MOLECULAR HYDROGEN IN PLANETARY NEBULAE J. W. V. Storey, B. L. Webster and P. Payne School of Physics, University of New South Wales Kensington, Australia M. A. Dopita Mt. Stromlo & Siding Spring Observatory Canberra, Australia ABSTRACT. A correlation has been found between strong molecular hydro- gen emission and the morphological type of a planetary nebula. Those with an equatorial toroid and bipolar extensions have H^ 1-0 S(l) stronger than Brackett Ύ. H? maps of several objects, and NGC 2346 in particular, are consistent with a fast stellar wind interacting with an anisotropic medium. The first detection of infrared lines of molecular hydrogen from a planetary nebula was made in 1975 in NGC 7027. Since that time, some 35 planetaries have been searched for in H? at various detection levels, and most planetaries have revealed a detectable emission of H^. The ra- tio of this emission to ionized gas content may vary over many orders of magnitude. We propose that planetary nebulae with very strong H~ emission be- long to one morphological class. These are characterised By a dominant equatorial toroid, and bipolar extensions. Planetaries of this form pre- dominantly fall into a class called Type I. Type I planetaries are dis- tinguished by their bipolar structure as well as a high Ν and He abun- dances, and some, but not all, have a pronounced equatorial toroid plus less dense extended polar lobes. To test our hypothesis we chose a se- ries of Type I planetaries to be observed in H^ on the Anglo-Australian Telescope. -
Proto-Planetary Nebula Observing Guide
Proto-Planetary Nebula Observing Guide www.reinervogel.net RA Dec CRL 618 Westbrook Nebula 04h 42m 53.6s +36° 06' 53" PK 166-6 1 HD 44179 Red Rectangle 06h 19m 58.2s -10° 38' 14" V777 Mon OH 231.8+4.2 Rotten Egg N. 07h 42m 16.8s -14° 42' 52" Calabash N. IRAS 09371+1212 Frosty Leo 09h 39m 53.6s +11° 58' 54" CW Leonis Peanut Nebula 09h 47m 57.4s +13° 16' 44" Carbon Star with dust shell M 2-9 Butterfly Nebula 17h 05m 38.1s -10° 08' 33" PK 10+18 2 IRAS 17150-3224 Cotton Candy Nebula 17h 18m 20.0s -32° 27' 20" Hen 3-1475 Garden-sprinkler Nebula 17h 45m 14. 2s -17° 56' 47" IRAS 17423-1755 IRAS 17441-2411 Silkworm Nebula 17h 47m 13.5s -24° 12' 51" IRAS 18059-3211 Gomez' Hamburger 18h 09m 13.3s -32° 10' 48" MWC 922 Red Square Nebula 18h 21m 15s -13° 01' 27" IRAS 19024+0044 19h 05m 02.1s +00° 48' 50.9" M 1-92 Footprint Nebula 19h 36m 18.9s +29° 32' 50" Minkowski's Footprint IRAS 20068+4051 20h 08m 38.5s +41° 00' 37" CRL 2688 Egg Nebula 21h 02m 18.8s +36° 41' 38" PK 80-6 1 IRAS 22036+5306 22h 05m 30.3s +53° 21' 32.8" IRAS 23166+1655 23h 19m 12.6s +17° 11' 33.1" Southern Objects ESO 172-7 Boomerang Nebula 12h 44m 45.4s -54° 31' 11" Centaurus bipolar nebula PN G340.3-03.2 Water Lily Nebula 17h 03m 10.1s -47° 00' 27" PK 340-03 1 IRAS 17163-3907 Fried Egg Nebula 17h 19m 49.3s -39° 10' 37.9" Finder charts measure 20° (with 5° circle) and 5° (with 1° circle) and were made with Cartes du Ciel by Patrick Chevalley (http://www.ap-i.net/skychart) Images are DSS Images (blue plates, POSS II or SERCJ) and measure 30’ by 30’ (http://archive.stsci.edu/cgi- bin/dss_plate_finder) and STScI Images (Hubble Space Telescope) Downloaded from www.reinervogel.net version 12/2012 DSS images copyright notice: The Digitized Sky Survey was produced at the Space Telescope Science Institute under U.S. -
Young Stars in NGC 6231 and the Sco OB1 Association
Handbook of Star Forming Regions Vol. II Astronomical Society of the Pacific, c 2008 Bo Reipurth, ed. Young Stars in NGC 6231 and the Sco OB1 Association Bo Reipurth Institute for Astronomy, University of Hawaii 640 N. Aohoku Place, Hilo, HI 96720, USA Abstract. NGC 6231 is a young cluster in the southern sky, around 3-5 Myr old, located at a distance of about 1.6 kpc at the near side of the Sagittarius spiral arm. It forms the nucleus of the extended Sco OB1 association. The cluster is very rich, with more than 100 massive stars, among them 15 O-stars. Radial velocity studies have revealed a very large binary fraction among these OB stars. The young low- mass population has recently been identified using deep X-ray observations. Within the large HII region Gum 55 that surrounds NGC 6231 there exists a major elephant trunk, which shows evidence for recent second-generation star formation in the form of young B-stars surrounded by reflection nebulae and a number of low-mass Hα emission stars. 1. Introduction The open cluster NGC 6231 (also known as De Cheseaux No. 9, Lacaille II.13, Dun- lop 499, Melotte 153, and Collinder 315) in Scorpius was first discovered by Giovanni Battista Hodierna, who included it in his 1654 ”De systemate orbis cometici; deque admirandis coeli characteribus” [Of the systematics of the world of comets, and on the admirable objects of the sky]. Subsequently, NGC 6231 was independently discovered by Edmond Halley, who included it as one of three nebulous objects in his 1678 catalog of southern stars (Ashworth 1981).