DOCSLIB.ORG

SIMBA Observations of the R Corona Australis Molecular Cloud?,??

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text

Load more

A&A 409, 235–244 (2003) Astronomy DOI: 10.1051/0004-6361:20031115 & c ESO 2003 Astrophysics SIMBA observations of the R Corona Australis molecular cloud?;?? R. Chini1,K.K¨ampgen1;2,B.Reipurth2, M. Albrecht1,E.Kreysa3,R.Lemke1,M.Nielbock4, L. A. Reichertz3,A.Sievers5,andR.Zylka6 1 Astronomisches Institut der Ruhr-Universit¨at Bochum, Universit¨atsstrasse 150, 44780 Bochum, Germany 2 Institute for Astronomy, University of Hawaii, 2680 Woodlawn Drive, Honolulu, HI 96822, USA 3 Max Planck Institut f¨ur Radioastronomie, Auf dem H¨ugel 69, 53121 Bonn, Germany 4 SEST, European Southern Observatory, Alonso de Cordova 3107, Santiago, Chile 5 IRAM, Avda. Divina Pastora 7, Nucleo Central, 18012 Granada, Spain 6 I. Physikalisches Institut, Universit¨at zu K¨oln, Z¨ulpicher Strasse 77, 50937 K¨oln, Germany Received 10 March 2003 / Accepted 16 July 2003 Abstract. We have mapped the R Corona Australis molecular cloud at 1.2 mm with SIMBA on SEST and detected 25 distinct dust emission peaks. While 7 of them coincide with positions of previously known young stars, 18 are seemingly not associated with any known stellar object. We discuss the nature of individual sources and conclude that there are at least four small concentrations of young objects located along the filamentary shaped cloud. A comparison with C18O data hints at the depletion of molecules in some of the cores. Our new results yield some conflicting arguments about whether star formation proceeds from north-west to south-east in the R Cr A cloud. Key words. ISM: dust, extinction – stars: circumstellar matter – stars: formation 1. Introduction counts (e.g. Rossano 1978; Andreazza & Vilas-Boas 1996; Cambr´esy 1999), reveal a cometary shaped cloud complex For more than a century, attention has been drawn to a high ex- oriented northwest-southeast which is about 6◦ long with the tinction region in Corona Australis where a number of variable abovementioned young stars located in the dense cometary stars are located. The R Corona Australis cloud coincides with head. This morphology suggests that star formation in the Rossano’s (1978) cloud A and is named after the highly vari- Corona Australis complex has been triggered by an external able Herbig Ae/Be star R Cr A (e.g. Joy 1945; Herbig 1960) influence which possibly originates in the Upper Centaurus- which is surrounded by a bright reflection nebula that also Lupus association (Harju et al. 1993). At a distance of varies with time (e.g. Graham & Phillips 1987). A major reflec- about 170 pc (Knude & Høg 1998), the Cr A cloud complex tion nebula surrounds the B8 star TY Cr A which is an eclips- is among the closest star-forming regions. ing PMS binary (e.g. Vaz 2001) and the neighbouring A0 star HD 176386. The two bright variable stars S Cr A and VV Cr A Surveys of the R Cr A cloud have revealed a population are both T Tauri stars and visual PMS binaries (e.g. Reipurth & of young, visible low-mass stars, either through the presence Zinnecker 1993). of Hα emission (e.g. Knacke et al. 1973; Marraco & Rydgren These young stars are associated with a large complex 1981) or as X-ray sources (e.g. Koyama et al. 1996; Neuh¨auser of dark clouds mapped in molecular and atomic transitions et al. 2000). Infrared surveys have uncovered a small clus- by, among others, Loren (1979), Cappa de Nicolau & P¨oppel ter, named the Coronet, of low-luminosity sources embedded (1991), Harju et al. (1993) and Yonekura et al. (1999). These around R Cr A (Taylor & Storey 1984; Wilking et al. 1986; data, together with large-scale extinction maps based on star Wilking et al. 1997). More deeply embedded sources have been identified through radio continuum observations (Brown 1987; Send offprint requests to: R. Chini, Suters et al. 1996; Harju et al. 2001) and millimetre contin- e-mail: [email protected] uum observations (Reipurth et al. 1993; Henning et al. 1994; ? Based on observations collected at the European Southern Saraceno et al. 1996). These young stars drive various outflows Observatory, La Silla, Chile. which are observed either as Herbig-Haro objects or as molec- ?? Appendices A and B are only available in electronic form at ular outflows (e.g. Hartigan & Graham 1987; Levreault 1988; http://www.edpsciences.org Graham 1993; Anderson et al. 1997). Article published by EDP Sciences and available at http://www.aanda.org or http://dx.doi.org/10.1051/0004-6361:20031115 236 R. Chini et al.: SIMBA observations of the R Corona Australis molecular cloud Fig. 1. The complete 1.2 mm mosaic of the R Cr A dark cloud consisting of 71 individual fastscanning maps. This and all the following figures containing SIMBA data are slightly Gaussian smoothed (2800 vs. a beam of 2400 ). The smoothed beam (2800) is indicated in the box to the lower right. The typical 1σ rms noise is 17 1mJy/beam; along the edges, the noise level is obviously higher. The contour lines start at 51 mJy/beam ± (=3 rms). Details of this mosaic are given in subsequent figures. In this paper, we present the first deep, large-scale survey measurements. Maps of Uranus were taken for calibration pur- of the R Corona Australis cloud at millimetre continuum wave- poses. A calibration accuracy of 15% was obtained. All data lengths. Our 1.2 mm maps reveal several small clusters of em- were reduced and analysed with MOPSI1 according to the in- bedded, very cold objects which we interpret in terms of con- structions of the SIMBA Observer’s Handbook (2002). A de- centrations of newborn low-mass stars. tailed description of the data reduction and the data analysis including the determination of the noise in the mosaic is pre- 2. Observations sented in Appendices A and B, respectively. The 1.2 mm continuum observations were carried out with the 37 channel bolometer array SIMBA (SEST Imaging 3. Results and discussion Bolometer Array) at the SEST (Swedish-ESO Submillimetre In the following section, we present and discuss the data from Telescope) on La Silla, Chile, during the commissioning pe- our 1.2 mm survey. Figure 1 shows the total mosaic of the riods in June, July and October 2001. We performed a mo- R Corona Australis region as covered by SIMBA. Table 1 saic that covers an area extending from north-west to south- summarises those 25 dust emission peaks – labelled “MMS” east of roughly 2000 1000 . The mosaic was constructed 00 × 00 (millimetre source) – which we consider to be bona fide de- by combining 71 individual fastscanning maps (8000 per s) of tections. They were selected according to the following crite- different sizes taken at different hour angles in order to re- ria: i) their S=N ratio is larger than 9 (see Appendix B.1 for duce scanning effects. The total integration time spent on the the definition of the S=N ratio); ii) their extent is larger or area was 978 min. The residual noise in the final co-added equal to the beam size; iii) their reality was checked within mosaic varies by 2 around 17 mJy/beam (rms) across the ± individual maps in order to exclude residuals caused by the region due to different numbers of coverages per area. The direction of fast-scanning. All entries in Table 1 are derived beam size of an individual bolometer channel is 2400 HPBW. from the original, unsmoothed mosaic. As to be seen in the Skydips were performed at least every three hours in or- overview in Fig. 1, there are additional peaks above the 3σ der to determine the atmospheric opacity. The zenith opac- ity values range from 0.160 to 0.364. The positional accuracy 1 MOPSI is a software package for infrared, millimetre and radio was determined to be 200–300 by performing frequent pointing data reduction developed and constantly upgraded by R. Zylka. R. Chini et al.: SIMBA observations of the R Corona Australis molecular cloud 237 Table 1. Source positions, peak intensities, morphology, flux densities and other designations for 25 mm sources detected by SIMBA. RCrA RA Dec I (1) Source size (a b)(2) S (3) Other designations 1:2mm × 1:2mm MMS (J2000) [mJy/beam] [00][mJy] h m s 11901 08:3 36◦5701900 260 (0) 25 25 290 S Cr A; ISO 116 h m s − × 21901 04:2 36◦5402300 140 h m s − 31901 06:6 36◦5402500 160 h m s − 41901 09:0 36◦5401800 138 h m s − 51901 14:6 36◦5400200 141 h m s − 61901 33:2 36◦5303500 268 h m s − 71901 38:1 36◦5400300 322 h m s − 81901 38:2 36◦5303600 336 HD 176386 h m s − 91901 41:7 36◦5802800 660 (0) 36 32 1320 IRS 2; TS 13.1; IRAS 21 h m s − × 10 19 01 45:9 36◦5504800 838 h m s − 11 19 01 46:6 36◦5603000 897 h m s − 12 19 01 49:2 36◦5702200 1173 IRS 5; TS 2.4 h m s − 13 19 01 55:5 36◦5703800 2315 confused; see text h m s − 14 19 01 58:0 37◦0100300 150 h m s − 15 19 02 02:4 37◦0103400 158 h m s − 16 19 02 05:0 37◦0103100 147 h m s − 17 19 02 04:8 37◦0000300 180 h m s − 18 19 02 08:6 37◦0004100 170 h m s − 19 19 02 12:4 36◦5701700 146 h m s − 20 19 02 15:3 37◦0103700 160 h m s − 21 19 02 17:8 37◦0103400 148 h m s − 22 19 02 40:7 37◦0801100 146 h m s − 23 19 02 59:0 37◦0703200 472 (126) 36 31 672 IRAS 18595-3712; IRAS 32c; − × ISO-CrA 182 h m s 24 19 03 06:9 37◦1204700 543 (42) 28 24 584 VV Cr A; IRAS 18597-3717 h m s − × 25 19 03 56:1 37◦1503200 250 − (1) Peak intensity measured above the zero level; the beam size is 2400.
Recommended publications
  • MESSIER 13 RA(2000) : 16H 41M 42S DEC(2000): +36° 27'

    MESSIER 13 RA(2000) : 16H 41M 42S DEC(2000): +36° 27'

    MESSIER 13 RA(2000) : 16h 41m 42s DEC(2000): +36° 27’ 41” BASIC INFORMATION OBJECT TYPE: Globular Cluster CONSTELLATION: Hercules BEST VIEW: Late July DISCOVERY: Edmond Halley, 1714 DISTANCE: 25,100 ly DIAMETER: 145 ly APPARENT MAGNITUDE: +5.8 APPARENT DIMENSIONS: 20’ Starry Night FOV: 1.00 Lyra FOV: 60.00 Libra MESSIER 6 (Butterfly Cluster) RA(2000) : 17Ophiuchus h 40m 20s DEC(2000): -32° 15’ 12” M6 Sagitta Serpens Cauda Vulpecula Scutum Scorpius Aquila M6 FOV: 5.00 Telrad Delphinus Norma Sagittarius Corona Australis Ara Equuleus M6 Triangulum Australe BASIC INFORMATION OBJECT TYPE: Open Cluster Telescopium CONSTELLATION: Scorpius Capricornus BEST VIEW: August DISCOVERY: Giovanni Batista Hodierna, c. 1654 DISTANCE: 1600 ly MicroscopiumDIAMETER: 12 – 25 ly Pavo APPARENT MAGNITUDE: +4.2 APPARENT DIMENSIONS: 25’ – 54’ AGE: 50 – 100 million years Telrad Indus MESSIER 7 (Ptolemy’s Cluster) RA(2000) : 17h 53m 51s DEC(2000): -34° 47’ 36” BASIC INFORMATION OBJECT TYPE: Open Cluster CONSTELLATION: Scorpius BEST VIEW: August DISCOVERY: Claudius Ptolemy, 130 A.D. DISTANCE: 900 – 1000 ly DIAMETER: 20 – 25 ly APPARENT MAGNITUDE: +3.3 APPARENT DIMENSIONS: 80’ AGE: ~220 million years FOV:Starry 1.00Night FOV: 60.00 Hercules Libra MESSIER 8 (THE LAGOON NEBULA) RA(2000) : 18h 03m 37s DEC(2000): -24° 23’ 12” Lyra M8 Ophiuchus Serpens Cauda Cygnus Scorpius Sagitta M8 FOV: 5.00 Scutum Telrad Vulpecula Aquila Ara Corona Australis Sagittarius Delphinus M8 BASIC INFORMATION Telescopium OBJECT TYPE: Star Forming Region CONSTELLATION: Sagittarius Equuleus BEST
  • The Lore of the Stars, for Amateur Campfire Sages

    The Lore of the Stars, for Amateur Campfire Sages

    obscure. Various claims have been made about Babylonian innovations and the similarity between the Greek zodiac and the stories, dating from the third millennium BCE, of Gilgamesh, a legendary Sumerian hero who encountered animals and characters similar to those of the zodiac. Some of the Babylonian constellations may have been popularized in the Greek world through the conquest of The Lore of the Stars, Alexander in the fourth century BCE. Alexander himself sent captured Babylonian texts back For Amateur Campfire Sages to Greece for his tutor Aristotle to interpret. Even earlier than this, Babylonian astronomy by Anders Hove would have been familiar to the Persians, who July 2002 occupied Greece several centuries before Alexander’s day. Although we may properly credit the Greeks with completing the Babylonian work, it is clear that the Babylonians did develop some of the symbols and constellations later adopted by the Greeks for their zodiac. Contrary to the story of the star-counter in Le Petit Prince, there aren’t unnumerable stars Cuneiform tablets using symbols similar to in the night sky, at least so far as we can see those used later for constellations may have with our own eyes. Only about a thousand are some relationship to astronomy, or they may visible. Almost all have names or Greek letter not. Far more tantalizing are the various designations as part of constellations that any- cuneiform tablets outlining astronomical one can learn to recognize. observations used by the Babylonians for Modern astronomers have divided the sky tracking the moon and developing a calendar. into 88 constellations, many of them fictitious— One of these is the MUL.APIN, which describes that is, they cover sky area, but contain no vis- the stars along the paths of the moon and ible stars.
  • Corona-Australis Dance I

    Corona-Australis Dance I

    A&A 634, A98 (2020) Astronomy https://doi.org/10.1051/0004-6361/201936708 & c P. A. B. Galli et al. 2020 Astrophysics Corona-Australis DANCe I. Revisiting the census of stars with Gaia-DR2 data? P. A. B. Galli1, H. Bouy1, J. Olivares1, N. Miret-Roig1, L. M. Sarro2, D. Barrado3, A. Berihuete4, and W. Brandner5 1 Laboratoire d’Astrophysique de Bordeaux, Univ. Bordeaux, CNRS, B18N, allée Geoffroy Saint-Hillaire, 33615 Pessac, France e-mail: [email protected] 2 Depto. de Inteligencia Artificial, UNED, Juan del Rosal, 16, 28040 Madrid, Spain 3 Centro de Astrobiología, Depto. de Astrofísica, INTA-CSIC, ESAC Campus, Camino Bajo del Castillo s/n, 28692 Villanueva de la Cañada, Madrid, Spain 4 Dept. Statistics and Operations Research, University of Cádiz, Campus Universitario Río San Pedro s/n, 11510 Puerto Real, Cádiz, Spain 5 Max Planck Institute for Astronomy, Königstuhl 17, 69117 Heidelberg, Germany Received 16 September 2019 / Accepted 11 December 2019 ABSTRACT Context. Corona-Australis is one of the nearest regions to the Sun with recent and ongoing star formation, but the current picture of its stellar (and substellar) content is not complete yet. Aims. We take advantage of the second data release of the Gaia space mission to revisit the stellar census and search for additional members of the young stellar association in Corona-Australis. Methods. We applied a probabilistic method to infer membership probabilities based on a multidimensional astrometric and photo- metric data set over a field of 128 deg2 around the dark clouds of the region. Results. We identify 313 high-probability candidate members to the Corona-Australis association, 262 of which had never been reported as members before.
  • Educator's Guide: Orion

    Educator's Guide: Orion

    Legends of the Night Sky Orion Educator’s Guide Grades K - 8 Written By: Dr. Phil Wymer, Ph.D. & Art Klinger Legends of the Night Sky: Orion Educator’s Guide Table of Contents Introduction………………………………………………………………....3 Constellations; General Overview……………………………………..4 Orion…………………………………………………………………………..22 Scorpius……………………………………………………………………….36 Canis Major…………………………………………………………………..45 Canis Minor…………………………………………………………………..52 Lesson Plans………………………………………………………………….56 Coloring Book…………………………………………………………………….….57 Hand Angles……………………………………………………………………….…64 Constellation Research..…………………………………………………….……71 When and Where to View Orion…………………………………….……..…77 Angles For Locating Orion..…………………………………………...……….78 Overhead Projector Punch Out of Orion……………………………………82 Where on Earth is: Thrace, Lemnos, and Crete?.............................83 Appendix………………………………………………………………………86 Copyright©2003, Audio Visual Imagineering, Inc. 2 Legends of the Night Sky: Orion Educator’s Guide Introduction It is our belief that “Legends of the Night sky: Orion” is the best multi-grade (K – 8), multi-disciplinary education package on the market today. It consists of a humorous 24-minute show and educator’s package. The Orion Educator’s Guide is designed for Planetarians, Teachers, and parents. The information is researched, organized, and laid out so that the educator need not spend hours coming up with lesson plans or labs. This has already been accomplished by certified educators. The guide is written to alleviate the fear of space and the night sky (that many elementary and middle school teachers have) when it comes to that section of the science lesson plan. It is an excellent tool that allows the parents to be a part of the learning experience. The guide is devised in such a way that there are plenty of visuals to assist the educator and student in finding the Winter constellations.
  • Constellation Is the Corona Australis

    Constellation Is the Corona Australis

    CORONA AUSTRALIS, THE SOUTHERN CROWN Corona Australis is a constellation in the southern celestial hemisphere. Its Latin name means "southern crown", and it is the southern counterpart of Corona Borealis, the northern crown. One of the 48 constellations listed by the 2nd-century astronomer Ptolemy, it remains one of the 88 modern constellations. The Ancient Greeks saw Corona Australis as a wreath rather than a crown and associated it with Sagittarius or Centaurus. Other cultures have likened the pattern to a turtle, ostrich nest, a tent, or even a hut belonging to a rock hyrax (a shrewmouse; a small, well-furred, rotund animals with short tails). Although fainter than its northern namesake, the oval - or horseshoe-shaped pattern of its brighter stars renders it distinctive. Alpha and Beta Coronae Australis are its two brightest stars with an apparent magnitude of around 4.1. Epsilon Coronae Australis is the brightest example of a W Ursae Majoris variable in the southern sky (an eclipsing contact binary). Lying alongside the Milky Way, Corona Australis contains one of the closest star-forming regions to our Solar System —a dusty dark nebula known as the Corona Australis Molecular Cloud, lying about 430 light years away. Within it are stars at the earliest stages of their lifespan. The variable stars R and TY Coronae Australis light up parts of the nebula, which varies in brightness accordingly. Corona Australis is bordered by Sagittarius to the north, Scorpius to the west, Telescopium to the south, and Ara to the southwest. The three-letter abbreviation for the constellation, as adopted by the International Astronomical Union in 1922, is 'CrA'.
  • THE CONSTELLATION MUSCA, the FLY Musca Australis (Latin: Southern Fly) Is a Small Constellation in the Deep Southern Sky

    THE CONSTELLATION MUSCA, the FLY Musca Australis (Latin: Southern Fly) Is a Small Constellation in the Deep Southern Sky

    THE CONSTELLATION MUSCA, THE FLY Musca Australis (Latin: Southern Fly) is a small constellation in the deep southern sky. It was one of twelve constellations created by Petrus Plancius from the observations of Pieter Dirkszoon Keyser and Frederick de Houtman and it first appeared on a 35-cm diameter celestial globe published in 1597 in Amsterdam by Plancius and Jodocus Hondius. The first depiction of this constellation in a celestial atlas was in Johann Bayer's Uranometria of 1603. It was also known as Apis (Latin: bee) for two hundred years. Musca remains below the horizon for most Northern Hemisphere observers. Also known as the Southern or Indian Fly, the French Mouche Australe ou Indienne, the German Südliche Fliege, and the Italian Mosca Australe, it lies partly in the Milky Way, south of Crux and east of the Chamaeleon. De Houtman included it in his southern star catalogue in 1598 under the Dutch name De Vlieghe, ‘The Fly’ This title generally is supposed to have been substituted by La Caille, about 1752, for Bayer's Apis, the Bee; but Halley, in 1679, had called it Musca Apis; and even previous to him, Riccioli catalogued it as Apis seu Musca. Even in our day the idea of a Bee prevails, for Stieler's Planisphere of 1872 has Biene, and an alternative title in France is Abeille. When the Northern Fly was merged with Aries by the International Astronomical Union (IAU) in 1929, Musca Australis was given its modern shortened name Musca. It is the only official constellation depicting an insect. Julius Schiller, who redrew and named all the 88 constellations united Musca with the Bird of Paradise and the Chamaeleon as mother Eve.
  • NANTEN Observations of Dense Cores in the Corona Australis Molecular Cloud

    NANTEN Observations of Dense Cores in the Corona Australis Molecular Cloud

    PASJ: Publ. Astron. Soc. Japan 51, 911-918 (1999) NANTEN Observations of Dense Cores in the Corona Australis Molecular Cloud Yoshinori YONEKURA Department of Earth and Life Sciences, Osaka Prefecture University, Sakai, Osaka 599-8531 E-mail (YY): [email protected] and Norikazu MIZUNO, Hiro SAITO, Akira MIZUNO, Hideo OGAWA* and Yasuo FUKUI Department of Astrophysics, Nagoya University, Chikusa-ku, Nagoya, ^64-8602 Downloaded from https://academic.oup.com/pasj/article/51/6/911/1467816 by guest on 30 September 2021 (Received 1999 August 26; accepted 1999 October 24) Abstract We carried out a C180 survey for dense molecular cores in the Corona Australis (CrA) molecular cloud with the NANTEN telescope. We observed 2.2 deg2 at a 2' grid spacing with a 2/7 beam, and 1980 positions were observed. We identified 8 C180 cores, whose typical line width, average column density, radius, mass, and average number density were 0.66 km s_1, 1.1 x 1022 cm-2, 0.13 pc, 18M®, and 1.4 x 104 cm-3, respectively. We found that AKomp, (Af(H2)), R, M, and n(H2) become larger along with an increase in the star-formation activity, whereas the ratio Mv-ir/M becomes smaller. A comparison of the present cores with those in Chamaeleon, Lupus, Ophiuchus, Taurus, and L 1333 indicates that star-forming cores tend to have a high column density, as well as a smaller MV-1T/M ratio. Key words: ISM: clouds — ISM: individual (Corona Australis Cloud) — ISM: molecules — stars: formation — radio lines: ISM 1. Introduction T CrA (FOe), TY CrA (B9e), and W CrA (Kl); there are also > 20 embedded IR sources, including the 'coro­ Recent observational studies have revealed that there net' cluster (Taylor, Storey 1984; Graham 1992; Wilking are a great variety of star-formation activities; only low- et al.
  • SFA Star Chart 1

    SFA Star Chart 1

    Nov 20 SFA Star Chart 1 - Northern Region 0h Dec 6 Nov 5 h 23 30º 1 h d Dec 21 h p Oct 21h s b 2 h 22 ANDROMEDA - Daughter of Cepheus and Cassiopeia Mirach Local Meridian for 8 PM q m ANTLIA - Air Pumpe p 40º APUS - Bird of Paradise n o i b g AQUILA - Eagle k ANDROMEDA Jan 5 u TRIANGULUM AQUARIUS - Water Carrier Oct 6 h z 3 21 LACERTA l h ARA - Altar j g ARIES - Ram 50º AURIGA - Charioteer e a BOOTES - Herdsman j r Schedar b CAELUM - Graving Tool x b a Algol Jan 20 b o CAMELOPARDALIS - Giraffe h Caph q 4 Sep 20 CYGNUS k h 20 g a 60º z CAPRICORNUS - Sea Goat Deneb z g PERSEUS d t x CARINA - Keel of the Ship Argo k i n h m a s CASSIOPEIA - Ethiopian Queen on a Throne c h CASSIOPEIA g Mirfak d e i CENTAURUS - Half horse and half man CEPHEUS e CEPHEUS - Ethiopian King Alderamin a d 70º CETUS - Whale h l m Feb 5 5 CHAMAELEON - Chameleon h i g h 19 Sep 5 i CIRCINUS - Compasses b g z d k e CANIS MAJOR - Larger Dog b r z CAMELOPARDALIS 7 h CANIS MINOR - Smaller Dog e 80º g a e a Capella CANCER - Crab LYRA Vega d a k AURIGA COLUMBA - Dove t b COMA BERENICES - Berenice's Hair Aug 21 j Feb 20 CORONA AUSTRALIS - Southern Crown Eltanin c Polaris 18 a d 6 d h CORONA BOREALIS - Northern Crown h q g x b q 30º 30º 80º 80º 40º 70º 50º 60º 60º 70º 50º CRATER - Cup 40º i e CRUX - Cross n z b Rastaban h URSA CORVUS - Crow z r MINOR CANES VENATICI - Hunting Dogs p 80º b CYGNUS - Swan h g q DELPHINUS - Dolphin Kocab Aug 6 e 17 DORADO - Goldfish q h h h DRACO o 7 DRACO - Dragon s GEMINI t t Mar 7 EQUULEUS - Little Horse HERCULES LYNX z i a ERIDANUS - River j
  • The Corona Australis Star Forming Region

    The Corona Australis Star Forming Region

    Handbook of Star Forming Regions Vol. II Astronomical Society of the Pacific, 2008 Bo Reipurth, ed. The Corona Australis Star Forming Region Ralph Neuh¨auser Astrophysikalisches Institut und Universitats-Sternwarte,¨ Schillergaßchen¨ 2-3, D-07745 Jena, Germany Jan Forbrich Harvard-Smithsonian Center for Astrophysics, 60 Garden Street MS 72, Cambridge, MA 02138, USA Abstract. At a distance of about 130 pc, the Corona Australis molecular cloud complex is one of the nearest regions with ongoing and/or recent star formation. It is a region with highly variable extinction of up to AV ∼ 45 mag, containing, at its core, the Coronet protostar cluster. There are now 55 known optically detected members, starting at late B spectral types. At the opposite end of the mass spectrum, there are two confirmed brown dwarf members and seven more candidate brown dwarfs. The CrA region has been most widely surveyed at infrared wavelengths, in X-rays, and in the millimeter continuum, while follow-up observations from centimeter radio to X-rays have focused on the Coronet cluster. 1. Introduction: The Corona Australis Cloud Corona Australis (southern crown), abbreviated CrA, is one of the 48 ancient constella- tions listed by Ptolemy, who called it Stephanos Notios (in Greek). The latin translation was corona notia, austrina, australis, meridiana, or meridionalis, from which Allen (1936) picked corona australis; see also Botley (1980) for a discussion of the name. For an overview, see Fig. 1. 1.1. The Discovery Given the convention for naming variable stars, R CrA was the first variable star no- ticed in the CrA constellation.
  • THE SKY TONIGHT Constellation Is Said to Represent Ganymede, the Handsome Prince of Capricornus Troy

    THE SKY TONIGHT Constellation Is Said to Represent Ganymede, the Handsome Prince of Capricornus Troy

    - October Oketopa HIGHLIGHTS Aquarius and Aquila In Greek mythology, the Aquarius THE SKY TONIGHT constellation is said to represent Ganymede, the handsome prince of Capricornus Troy. His good looks attracted the attention of Zeus, who sent the eagle The Greeks associated Capricornus Aquila to kidnap him and carry him with Aegipan, who was one of the to Olympus to serve as a cupbearer Panes - a group of half-goat men to the gods. Because of this story, who often had goat legs and horns. Ganymede was sometimes seen as the god of homosexual relations. He Aegipan assumed the form of a fish- also gives his name to one of the tailed goat and fled into the ocean moons of Jupiter, which are named to flee the great monster Typhon. after the lovers of Zeus. Later, he aided Zeus in defeating Typhon and was rewarded by being To locate Aquarius, first find Altair, placed in the stars. the brightest star in the Aquila constellation. Altair is one of the To find Capricornus (highlighted in closest stars to Earth that can be seen orange on the star chart), first locate with the naked eye, at a distance the Aquarius constellation, then of 17 light years. From Altair, scan look to the south-west along the east-south-east to find Aquarius ecliptic line (the dotted line on the (highlighted in yellow on the star chart). star chart). What’s On in October? October shows at Perpetual Guardian Planetarium, book at Museum Shop or online. See website for show times and - details: otagomuseum.nz October Oketopa SKY GUIDE Capturing the Cosmos Planetarium show.
  • THE SKY TONIGHT Romans About Two Thousand Years Ago

    THE SKY TONIGHT Romans About Two Thousand Years Ago

    - Southern Birds JULY HuRAE SKY GUIDE Most constellations visible in the northern sky in Dunedin were named by the Greeks and THE SKY TONIGHT Romans about two thousand years ago. These constellations are predominantly tied to myths and legends that explained how the stars were Moon Landing Anniversary put in the sky. The constellations in the southern The 20th of July this year marks fifty years sky, however, are not visible in the northern since humans first walked on the moon. hemisphere and so were not seen by Europeans The Apollo 11 mission was manned by three until the 15th and 16th centuries. These astronauts: Neil Armstrong, Buzz Aldrin, and constellations were given more practical names Michael Collins. They flew for four days after related to the journeys of the explorers, rather launch before reaching the moon’s orbit. than being based on any mythological stories. Neil Armstrong and Buzz Aldrin piloted the lunar module to the surface of the moon and In the late 1500s, the Dutch embarked on many collected 47.5kg of lunar material before trade voyages around Africa and the East Indies. returning to the command module and Navigation on these trips proved to be quite heading home. What’s truly amazing is that this difficult, as there were no accurate maps of the was accomplished with a computer the size of southern skies. Petrus Plancius was a mapmaker a car, with less processing power than today’s who commissioned a pilot, Pieter Keyser, to pocket calculators. record the position of the stars in the southern skies.
  • An Aboriginal Australian Record of the Great Eruption of Eta Carinae

    An Aboriginal Australian Record of the Great Eruption of Eta Carinae

    Accepted in the ‘Journal for Astronomical History & Heritage’, 13(3): in press (November 2010) An Aboriginal Australian Record of the Great Eruption of Eta Carinae Duane W. Hamacher Department of Indigenous Studies, Macquarie University, NSW, 2109, Australia [email protected] David J. Frew Department of Physics & Astronomy, Macquarie University, NSW, 2109, Australia [email protected] Abstract We present evidence that the Boorong Aboriginal people of northwestern Victoria observed the Great Eruption of Eta (η) Carinae in the nineteenth century and incorporated the event into their oral traditions. We identify this star, as well as others not specifically identified by name, using descriptive material presented in the 1858 paper by William Edward Stanbridge in conjunction with early southern star catalogues. This identification of a transient astronomical event supports the assertion that Aboriginal oral traditions are dynamic and evolving, and not static. This is the only definitive indigenous record of η Carinae’s outburst identified in the literature to date. Keywords: Historical Astronomy, Ethnoastronomy, Aboriginal Australians, stars: individual (η Carinae). 1 Introduction Aboriginal Australians had a significant understanding of the night sky (Norris & Hamacher, 2009) and frequently incorporated celestial objects and transient celestial phenomena into their oral traditions, including the sun, moon, stars, planets, the Milky Way and Magellanic Clouds, eclipses, comets, meteors, and impact events. While Australia is home to hundreds of Aboriginal groups, each with a distinct language and culture, few of these groups have been studied in depth for their traditional knowledge of the night sky. We refer the interested reader to the following reviews on Australian Aboriginal astronomy: Cairns & Harney (2003), Clarke (1997; 2007/2008), Fredrick (2008), Haynes (1992; 2000), Haynes et al.