A Galaxy Classification Grid That Better Recognises Early-Type Galaxy
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Infrared Spectroscopy of Nearby Radio Active Elliptical Galaxies
The Astrophysical Journal Supplement Series, 203:14 (11pp), 2012 November doi:10.1088/0067-0049/203/1/14 C 2012. The American Astronomical Society. All rights reserved. Printed in the U.S.A. INFRARED SPECTROSCOPY OF NEARBY RADIO ACTIVE ELLIPTICAL GALAXIES Jeremy Mould1,2,9, Tristan Reynolds3, Tony Readhead4, David Floyd5, Buell Jannuzi6, Garret Cotter7, Laura Ferrarese8, Keith Matthews4, David Atlee6, and Michael Brown5 1 Centre for Astrophysics and Supercomputing Swinburne University, Hawthorn, Vic 3122, Australia; [email protected] 2 ARC Centre of Excellence for All-sky Astrophysics (CAASTRO) 3 School of Physics, University of Melbourne, Melbourne, Vic 3100, Australia 4 Palomar Observatory, California Institute of Technology 249-17, Pasadena, CA 91125 5 School of Physics, Monash University, Clayton, Vic 3800, Australia 6 Steward Observatory, University of Arizona (formerly at NOAO), Tucson, AZ 85719 7 Department of Physics, University of Oxford, Denys, Oxford, Keble Road, OX13RH, UK 8 Herzberg Institute of Astrophysics Herzberg, Saanich Road, Victoria V8X4M6, Canada Received 2012 June 6; accepted 2012 September 26; published 2012 November 1 ABSTRACT In preparation for a study of their circumnuclear gas we have surveyed 60% of a complete sample of elliptical galaxies within 75 Mpc that are radio sources. Some 20% of our nuclear spectra have infrared emission lines, mostly Paschen lines, Brackett γ , and [Fe ii]. We consider the influence of radio power and black hole mass in relation to the spectra. Access to the spectra is provided here as a community resource. Key words: galaxies: elliptical and lenticular, cD – galaxies: nuclei – infrared: general – radio continuum: galaxies ∼ 1. INTRODUCTION 30% of the most massive galaxies are radio continuum sources (e.g., Fabbiano et al. -
Messier Plus Marathon Text
Messier Plus Marathon Object List by Wally Brown & Bob Buckner with additional objects by Mike Roos Object Data - Saguaro Astronomy Club Score is most numbered objects in a single night. Tiebreaker is count of un-numbered objects Observer Name Date Address Marathon Obects __________ Tiebreaker Objects ________ SEQ OBJECT TYPE CON R.A. DEC. RISE TRANSIT SET MAG SIZE NOTES TIME M 53 GLOCL COM 1312.9 +1810 7:21 14:17 21:12 7.7 13.0' NGC 5024, !B,vC,iR,vvmbM,st 12.. NGC 5272, !!,eB,vL,vsmbM,st 11.., Lord Rosse-sev dark 1 M 3 GLOCL CVN 1342.2 +2822 7:11 14:46 22:20 6.3 18.0' marks within 5' of center 2 M 5 GLOCL SER 1518.5 +0205 10:17 16:22 22:27 5.7 23.0' NGC 5904, !!,vB,L,eCM,eRi, st mags 11...;superb cluster M 94 GALXY CVN 1250.9 +4107 5:12 13:55 22:37 8.1 14.4'x12.1' NGC 4736, vB,L,iR,vsvmbM,BN,r NGC 6121, Cl,8 or 10 B* in line,rrr, Look for central bar M 4 GLOCL SCO 1623.6 -2631 12:56 17:27 21:58 5.4 36.0' structure M 80 GLOCL SCO 1617.0 -2258 12:36 17:21 22:06 7.3 10.0' NGC 6093, st 14..., Extremely rich and compressed M 62 GLOCL OPH 1701.2 -3006 13:49 18:05 22:21 6.4 15.0' NGC 6266, vB,L,gmbM,rrr, Asymmetrical M 19 GLOCL OPH 1702.6 -2615 13:34 18:06 22:38 6.8 17.0' NGC 6273, vB,L,R,vCM,rrr, One of the most oblate GC 3 M 107 GLOCL OPH 1632.5 -1303 12:17 17:36 22:55 7.8 13.0' NGC 6171, L,vRi,vmC,R,rrr, H VI 40 M 106 GALXY CVN 1218.9 +4718 3:46 13:23 22:59 8.3 18.6'x7.2' NGC 4258, !,vB,vL,vmE0,sbMBN, H V 43 M 63 GALXY CVN 1315.8 +4201 5:31 14:19 23:08 8.5 12.6'x7.2' NGC 5055, BN, vsvB stell. -
Stellar Tidal Streams As Cosmological Diagnostics: Comparing Data and Simulations at Low Galactic Scales
RUPRECHT-KARLS-UNIVERSITÄT HEIDELBERG DOCTORAL THESIS Stellar Tidal Streams as Cosmological Diagnostics: Comparing data and simulations at low galactic scales Author: Referees: Gustavo MORALES Prof. Dr. Eva K. GREBEL Prof. Dr. Volker SPRINGEL Astronomisches Rechen-Institut Heidelberg Graduate School of Fundamental Physics Department of Physics and Astronomy 14th May, 2018 ii DISSERTATION submitted to the Combined Faculties of the Natural Sciences and Mathematics of the Ruperto-Carola-University of Heidelberg, Germany for the degree of DOCTOR OF NATURAL SCIENCES Put forward by GUSTAVO MORALES born in Copiapo ORAL EXAMINATION ON JULY 26, 2018 iii Stellar Tidal Streams as Cosmological Diagnostics: Comparing data and simulations at low galactic scales Referees: Prof. Dr. Eva K. GREBEL Prof. Dr. Volker SPRINGEL iv NOTE: Some parts of the written contents of this thesis have been adapted from a paper submitted as a co-authored scientific publication to the Astronomy & Astrophysics Journal: Morales et al. (2018). v NOTE: Some parts of this thesis have been adapted from a paper accepted for publi- cation in the Astronomy & Astrophysics Journal: Morales, G. et al. (2018). “Systematic search for tidal features around nearby galaxies: I. Enhanced SDSS imaging of the Local Volume". arXiv:1804.03330. DOI: 10.1051/0004-6361/201732271 vii Abstract In hierarchical models of galaxy formation, stellar tidal streams are expected around most galaxies. Although these features may provide useful diagnostics of the LCDM model, their observational properties remain poorly constrained. Statistical analysis of the counts and properties of such features is of interest for a direct comparison against results from numeri- cal simulations. In this work, we aim to study systematically the frequency of occurrence and other observational properties of tidal features around nearby galaxies. -
April Constellations of the Month
April Constellations of the Month Leo Small Scope Objects: Name R.A. Decl. Details M65! A large, bright Sa/Sb spiral galaxy. 7.8 x 1.6 arc minutes, magnitude 10.2. Very 11hr 18.9m +13° 05’ (NGC 3623) high surface brighness showing good detail in medium sized ‘scopes. M66! Another bright Sb galaxy, only 21 arc minutes from M65. Slightly brighter at mag. 11hr 20.2m +12° 59’ (NGC 3627) 9.7, measuring 8.0 x 2.5 arc minutes. M95 An easy SBb barred spiral, 4 x 3 arc minutes in size. Magnitude 10.5, with 10hr 44.0m +11° 42’ a bright central core. The bar and outer ring of material will require larger (NGC 3351) aperature and dark skies. M96 Another bright Sb spiral, about 42 arc minutes east of M95, but larger and 10hr 46.8m +11° 49’ (NGC 3368) brighter. 6 x 4 arc minutes, magnitude 10.1. Located about 48 arc minutes NNE of M96. This small elliptical galaxy measures M105 only 2 x 2.1 arc minutes, but at mag. 10.3 has very high surface brightness. 10hr 47.8m +12° 35’ (NGC 3379) Look for NGC 3384! (110NGC) and NGC 3389 (mag 11.0 and 12.2) which form a small triangle with M105. NGC 3384! 10hr 48.3m +12° 38’ See comment for M105. The brightest galaxy in Leo, this Sb/Sc spiral galaxy shines at mag. 9.5. Look for NGC 2903!! 09hr 32.2m +21° 30’ a hazy patch 11 x 4.7 arc minutes in size 1.5° south of l Leonis. -
PMAS-PPAK Integral-Field Spectroscopy of Nearby Seyfert And
PMAS-PPAK integral-field spectroscopy of nearby Seyfert and normal spiral galaxies I. The central kiloparsecs of NGC 4138 Bartakov´ a´ T.1, Jungwiert B.2,3,Sanchez´ S. F.4,5, Stoklasova´ I.2, Emsellem E.6, Ferruit P.7, Jahnke K.8, Mundell C.9, Tacconi-Garman L. E.6, Vergani D.10, Wisotzki L.11 1 Department of Theoretical Physics and Astrophysics, Faculty of Science, Masaryk University, Brno, Czech Republic; 2 Astronomical Institute, Academy of Science of the Czech Republic, Prague, Czech Republic; 3 Astronomical Institute of the Charles University in Prague, Czech Republic; 4 Centro de Estudios de F´ısica del Cosmos de Aragon´ (CEFCA), Teruel, Spain; 5 Centro Astronomico´ Hispano-Aleman,´ Calar Alto, Almer´ıa, Spain; 6 European Southern Observatory, Garching, Germany; 7 CRAL-Observatoire de Lyon, Saint-Genis-Laval, France; 8 Max-Planck-Institut fur Astronomie, Heidelberg, Germany; 9 Astrophysics Research Institute, Liverpool John Moores University, United Kingdom; 10 INAF-Osservatorio Astronomico di Bologna, Italy; 11 Astrophysical Institute Potsdam, Germany. email: [email protected] Project overview These peculiarities are suspected to be related to a minor merger, however they could also be related to a destroyed Ratio Ha/Hb |2.5/*| Ratio [SII]6717/[SII]6731 |1.15/2.0| We study properties of ionized gas, gas/stellar kinematics bar, or a combination of both. New studies are necessary 30 6 30 2 5.5 1.9 and stellar populations in central regions (a few inner 20 20 to understand the galaxy history and mass transfer within 1.8 5 kiloparsecs) of four pairs of nearby Seyfert (NGC 5194, 10 10 1.7 the inner kiloparsecs. -
115 Abell Galaxy Cluster # 373
WINTER Medium-scope challenges 271 # # 115 Abell Galaxy Cluster # 373 Target Type RA Dec. Constellation Magnitude Size Chart AGCS 373 Galaxy cluster 03 38.5 –35 27.0 Fornax – 180 ′ 5.22 Chart 5.22 Abell Galaxy Cluster (South) 373 272 Cosmic Challenge WINTER Nestled in the southeast corner of the dim early winter western suburbs. Deep photographs reveal that NGC constellation Fornax, adjacent to the distinctive triangle 1316 contains many dust clouds and is surrounded by a formed by 6th-magnitude Chi-1 ( 1), Chi-2 ( 2), and complex envelope of faint material, several loops of Chi-3 ( 3) Fornacis, is an attractive cluster of galaxies which appear to engulf a smaller galaxy, NGC 1317, 6 ′ known as Abell Galaxy Cluster – Southern Supplement to the north. Astronomers consider this to be a case of (AGCS) 373. In addition to his research that led to the galactic cannibalism, with the larger NGC 1316 discovery of more than 80 new planetary nebulae in the devouring its smaller companion. The merger is further 1950s, George Abell also examined the overall structure signaled by strong radio emissions being telegraphed of the universe. He did so by studying and cataloging from the scene. 2,712 galaxy clusters that had been captured on the In my 8-inch reflector, NGC 1316 appears as a then-new National Geographic Society–Palomar bright, slightly oval disk with a distinctly brighter Observatory Sky Survey taken with the 48-inch Samuel nucleus. NGC 1317, about 12th magnitude and 2 ′ Oschin Schmidt camera at Palomar Observatory. In across, is visible in a 6-inch scope, although averted 1958, he published the results of his study as a paper vision may be needed to pick it out. -
Do Normal Galaxies Host a Black Hole? the High Energy Perspective
DO NORMAL GALAXIES HOST A BLACK HOLE? THE HIGH ENERGY PERSPECTIVE 1 Y. Terashima2 Nagoya University ABSTRACT We review ASCA results on a search for low luminosity active nuclei at the center of nearby normal galaxies. More than a dozen low-luminosity AGN have been discovered with 2–10 keV − − luminosity in the range 1040 41 ergs s 1. Their X-ray properties are in some respects similar to those of luminous Seyfert galaxies, but differ in other respects. We also present estimated black hole masses in low luminosity AGNs and a drastic activity decline in the nucleus of the radio galaxy Fornax A. These results altogether suggest that relics of the past luminous AGNs lurk in nearby normal galaxies. KEYWORDS: Galaxies; Low luminosity AGNs; LINERs; Black holes 1. Introduction The number density of quasars is peaked at a redshift of z ∼ 2 and rapidly de- creases toward smaller redshifts. In the local universe, there is no AGN emitting at huge luminosity like quasars. These facts infer that quasars evolve to supermassive black holes in nearby apparently normal galaxies (e.g. Rees 1990). The growing evidence for supermassive black holes in nearby galaxies are ob- tained from recent optical and radio observations of gas/stellar kinematics around the center of galaxies (e.g. Ho 1998a; Magorrian et al. 1998; Kormendy & Rich- stone 1995). If fueling to the supermassive black hole takes place with a small arXiv:astro-ph/9905218v1 17 May 1999 mass accretion rate, they are expected to be observed as very low luminosity AGNs compared to quasars. Recent optical spectroscopic surveys have shown that low level activity is fairly common in nearby galaxies. -
Celebrating the Wonder of the Night Sky
Celebrating the Wonder of the Night Sky The heavens proclaim the glory of God. The skies display his craftsmanship. Psalm 19:1 NLT Celebrating the Wonder of the Night Sky Light Year Calculation: Simple! [Speed] 300 000 km/s [Time] x 60 s x 60 m x 24 h x 365.25 d [Distance] ≈ 10 000 000 000 000 km ≈ 63 000 AU Celebrating the Wonder of the Night Sky Milkyway Galaxy Hyades Star Cluster = 151 ly Barnard 68 Nebula = 400 ly Pleiades Star Cluster = 444 ly Coalsack Nebula = 600 ly Betelgeuse Star = 643 ly Helix Nebula = 700 ly Helix Nebula = 700 ly Witch Head Nebula = 900 ly Spirograph Nebula = 1 100 ly Orion Nebula = 1 344 ly Dumbbell Nebula = 1 360 ly Dumbbell Nebula = 1 360 ly Flame Nebula = 1 400 ly Flame Nebula = 1 400 ly Veil Nebula = 1 470 ly Horsehead Nebula = 1 500 ly Horsehead Nebula = 1 500 ly Sh2-106 Nebula = 2 000 ly Twin Jet Nebula = 2 100 ly Ring Nebula = 2 300 ly Ring Nebula = 2 300 ly NGC 2264 Nebula = 2 700 ly Cone Nebula = 2 700 ly Eskimo Nebula = 2 870 ly Sh2-71 Nebula = 3 200 ly Cat’s Eye Nebula = 3 300 ly Cat’s Eye Nebula = 3 300 ly IRAS 23166+1655 Nebula = 3 400 ly IRAS 23166+1655 Nebula = 3 400 ly Butterfly Nebula = 3 800 ly Lagoon Nebula = 4 100 ly Rotten Egg Nebula = 4 200 ly Trifid Nebula = 5 200 ly Monkey Head Nebula = 5 200 ly Lobster Nebula = 5 500 ly Pismis 24 Star Cluster = 5 500 ly Omega Nebula = 6 000 ly Crab Nebula = 6 500 ly RS Puppis Variable Star = 6 500 ly Eagle Nebula = 7 000 ly Eagle Nebula ‘Pillars of Creation’ = 7 000 ly SN1006 Supernova = 7 200 ly Red Spider Nebula = 8 000 ly Engraved Hourglass Nebula -
Galaxy Classification Questions of the Day
Galaxy classification Questions of the Day • What are elliptical, spiral, lenticular and dwarf galaxies? • What is the Hubble sequence? • What determines the colors of galaxies? Top View of the Milky Way The MW is a “spiral” galaxy, or a “late type” galaxy. The different components have different colors, motions, and chemical compositions different origins! Other Late Type Spiral Galaxies • More disk than bulge (if any!). • High current star formation. These are also “late-type” galaxies. Apparent shape depends on orientation Other Types: “Early type galaxies” • More bulge than disk. • Low current star formation. “Sombrero Galaxy” And even earlier type galaxies: • Elliptical Galaxies (or just “ellipticals”) – No disk! All bulge! Have evolved to the point – Very little gas where no gas is left for – Probably old! making new stars! “spheroidals” And in between, “lenticulars” • Just a hint of a disk. • Low current star formation. “S0” galaxies: Like ellipticals, but usually a bit flatter. Many galaxies have “bars” – linear arrangements of stars (The Milky Way has a bar!) All of these different types of galaxy fit nicely into a sequence. Ellipticals Unbarred and Barred Spirals Lenticulars Number indicates how flat the elliptical is Lowercase “a”, “b”, “c” indicates how unlike the spiral is to an elliptical Things that vary along the Hubble Sequence: 1. “Bulge-to-Disk Ratio” 2. Lumpiness of the spiral arms 3. How tightly the spiral arms are wound E Sa Sb Sc “early type” “late type” Things that vary along the Hubble Sequence: 1. “Bulge-to-Disk Ratio” 2. Lumpiness of the spiral arms 3. How tightly the spiral arms are wound E Sa Sb Sc Note: These are not exact trends! Galaxies are much more complex than stars! 1. -
The Evolution of Galaxy Morphology
The Morphological Evolution of Galaxies Roberto G. Abraham Sidney van den Bergh Dept. of Astronomy & Dominion Astrophysical Observatory Astrophysics Herzberg Institute of Astrophysics University of Toronto National Research Council of Canada 60 St. George Street Victoria, British Columbia Toronto, Ontario M5S 3H8, V9E 2E7, Canada Canada ABSTRACT Many galaxies appear to have taken on their familiar appearance relatively recently. In the distant Universe, galaxy morphology started to deviate significantly (and systematically) from that of nearby galaxies at redshifts, z, as low as z = 0.3. This corresponds to a time ~3.5 Gyr in the past, which is only ~25% of the present age of the Universe. Beyond z = 0.5 (5 Gyr in the past) spiral arms are less well-developed and more chaotic, and barred spiral galaxies may become rarer. By z = 1, around 30% of the galaxy population is sufficiently peculiar that classification on Hubble’s traditional “tuning fork” system is meaningless. On the other hand, some characteristics of galaxies do not seem to have changed much over time. The co-moving space density of luminous disk galaxies has not changed significantly since z = 1, indicating that while the general appearance of these objects has continuously changed with cosmic epoch, their overall numbers have been conserved. Attempts to explain these results with hierarchical models for the formation of galaxies have met with mixed success. denoted Sa, Sb, and Sc (SBa, SBb, SBc in of Hubble’s classification system are Introduction the case of barred spirals). A final “catch- based on the idea that most matter in the all” category for irregular galaxies is also Universe is not in stellar or gaseous form, Nearby galaxies are usually classified on included. -
New Type of Black Hole Detected in Massive Collision That Sent Gravitational Waves with a 'Bang'
New type of black hole detected in massive collision that sent gravitational waves with a 'bang' By Ashley Strickland, CNN Updated 1200 GMT (2000 HKT) September 2, 2020 <img alt="Galaxy NGC 4485 collided with its larger galactic neighbor NGC 4490 millions of years ago, leading to the creation of new stars seen in the right side of the image." class="media__image" src="//cdn.cnn.com/cnnnext/dam/assets/190516104725-ngc-4485-nasa-super-169.jpg"> Photos: Wonders of the universe Galaxy NGC 4485 collided with its larger galactic neighbor NGC 4490 millions of years ago, leading to the creation of new stars seen in the right side of the image. Hide Caption 98 of 195 <img alt="Astronomers developed a mosaic of the distant universe, called the Hubble Legacy Field, that documents 16 years of observations from the Hubble Space Telescope. The image contains 200,000 galaxies that stretch back through 13.3 billion years of time to just 500 million years after the Big Bang. " class="media__image" src="//cdn.cnn.com/cnnnext/dam/assets/190502151952-0502-wonders-of-the-universe-super-169.jpg"> Photos: Wonders of the universe Astronomers developed a mosaic of the distant universe, called the Hubble Legacy Field, that documents 16 years of observations from the Hubble Space Telescope. The image contains 200,000 galaxies that stretch back through 13.3 billion years of time to just 500 million years after the Big Bang. Hide Caption 99 of 195 <img alt="A ground-based telescope&amp;#39;s view of the Large Magellanic Cloud, a neighboring galaxy of our Milky Way. -
High Velocity Dispersion in a Rare Grand Design Spiral Galaxy at Redshift Z =2.18
High Velocity Dispersion in a Rare Grand Design Spiral Galaxy at Redshift z =2.18 Nature, in press (July 19 2012) 1 2 3 4 David R. Law , Alice E. Shapley , Charles C. Steidel , Naveen A. Reddy , Charlotte R. 5 6 Christensen , Dawn K. Erb 1 Dunlap Institute for Astronomy & Astrophysics, University of Toronto, 50 St. George Street, Toronto M5S 3H4, Ontario, Canada 2 Department of Physics and Astronomy, University of California, Los Angeles, CA 90095 3 California Institute of Technology, MS 249-17, Pasadena, CA 91125 4 Department of Physics and Astronomy, University of California, Riverside, CA 92521 5 Steward Observatory, 933 North Cherry Ave, Tucson, AZ 85721 6 Department of Physics, University of Wisconsin-Milwaukee, Milwaukee, WI 53211 Although relatively common in the local Universe, only one grand-design spiral galaxy has been spectroscopically confirmed1 to lie at z>2 (HDFX 28; z=2.011), and may prove to be a major merger that simply resembles a spiral in projection. The rarity of spirals has been explained as a result of disks being dynamically ‘hot’ at z>2 2,3,4,5 which may instead favor the formation of commonly-observed clumpy structures 6,7,8,9,10. Alternatively, current instrumentation may simply not be sensitive enough to detect spiral structures comparable to those in the modern Universe11. At redshifts <2, the velocity dispersion of disks decreases12, and spiral galaxies are more numerous by z~1 7,13,14,15. Here we report observations of the grand design spiral galaxy Q2343-BX442 at z=2.18. Spectroscopy of ionized gas shows that the disk is dynamically hot, implying an uncertain origin for the spiral structure.