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We Had a Great Time on the Trip. We Had Some Representatives from the Vandenberg and Santa Barbara Clubs Along with Us for the Trip
We had a great time on the trip. We had some representatives from the Vandenberg and Santa Barbara clubs along with us for the trip. The most notable thing on the trip up was a stop in La Canada Flintridge to refuel the bus and get a bite to eat. I pulled out my PST Coronado and did a little impromptu public Sun Gazing. The Sun was pretty active with a number of platform prominences as well as the ever-present flame types. A distinct sunspot group in a very disturbed area of the Sun with a bright spot had me wondering if there was a flare in progress (There wasn’t.) The patrons at the tables outside didn’t seem to object to seeing the Sun either. I had a little bit of a scare when we first got up to the gate as a couple of people who were going to meet us there were nowhere to be seen. Fortunately one of them was already on the grounds and the other showed up while we were in the Museum. Relief! As it turned out we all went on the tour of the grounds. Our tour guide Greg gave us a tour starting outside the 60” Dome. He talked about the various Solar Telescopes -the old Snow telescope which was always a non-performer because of the design of the building- too many air currents. He talked about the rivalry over the 60 and 150 ft tower solar instruments (looks like UCLA won this one over USC.) And we got a good look at the 150 ft tower. -
198 7Apj. . .312L. .11J the Astrophysical Journal, 312:L11-L15
.11J The Astrophysical Journal, 312:L11-L15,1987 January 1 .312L. © 1987. The American Astronomical Society. All rights reserved. Printed in U.S.A. 7ApJ. 198 INTERSTELLAR DUST IN SHAPLEY-AMES ELLIPTICAL GALAXIES M. Jura and D. W. Kim Department of Astronomy, University of California, Los Angeles AND G. R. Knapp and P. Guhathakurta Princeton University Observatory Received 1986 August 11; accepted 1986 September 30 ABSTRACT We have co-added the IRAS survey data at the positions of the brightest elliptical galaxies in the Revised Shapley-Ames Catalog to increase the sensitivity over that of the IRAS Point Source Catalog. More than half of 7 8 the galaxies (with Bj< \\ mag) are detected at 100 /xm with flux levels indicating, typically, 10 or 10 M0 of cold interstellar matter. The presence of cold gas in ellipticals thus appears to be the rule rather than the exception. Subject headings: galaxies: general — infrared: sources I. INTRODUCTION infrared emission from the elliptical galaxy in the line of sight. The traditional view of early-type galaxies is that they are Our criteria for a real detection are as follows: essentially free of interstellar matter. However, with advances 1. The optical position of the galaxy and the position of the in instrumental sensitivity, it has become possible to observe IRAS source agree to better than V. (The agreement is usually 21 cm emission (Knapp, Turner, and Cunniffe 1985; Wardle much better than T.) and Knapp 1986), optical dust patches (Sadler and Gerhard 2. The flux is at least 3 times the r.m.s. noise. -
Arxiv:0807.0009V2
Draft version October 29, 2018 A Preprint typeset using LTEX style emulateapj v. 08/22/09 THE RESOLVED PROPERTIES OF EXTRAGALACTIC GIANT MOLECULAR CLOUDS Alberto D. Bolatto1, Adam K. Leroy2, Erik Rosolowsky3,4, Fabian Walter2, & Leo Blitz5 Draft version October 29, 2018 ABSTRACT We use high spatial resolution observations of CO to systematically measure the resolved size-line width, luminosity-line width, luminosity-size, and the mass-luminosity relations of Giant Molecular Clouds (GMCs) in a variety of extragalactic systems. Although the data are heterogeneous we analyze them in a consistent manner to remove the biases introduced by limited sensitivity and resolution, thus obtaining reliable sizes, velocity dispersions, and luminosities. We compare the results obtained in dwarf galaxies with those from the Local Group spiral galaxies. We find that extragalactic GMC properties measured across a wide range of environments are very much compatible with those in the Galaxy. The property that shows the largest variability is their resolved brightness temperature, although even that is similar to the average Galactic value in most sources. We use these results to investigate metallicity trends in the cloud average column density and virial CO-to-H2 factor. We find that these measurements do not accord with simple predictions from photoionization-regulated star formation theory, although this could be due to the fact that we do not sample small enough spatial scales or the full gravitational potential of the molecular cloud. We also find that the virial CO-to-H2 conversion factor in CO-bright GMCs is very similar to Galactic, and that the excursions do not show a measurable metallicity trend. -
Long-Period Variables in NGC 147 and NGC 185⋆
A&A 532, A78 (2011) Astronomy DOI: 10.1051/0004-6361/201116951 & c ESO 2011 Astrophysics Long-period variables in NGC 147 and NGC 185 D. Lorenz1, T. Lebzelter1,W.Nowotny1, J. Telting2, F. Kerschbaum1,H.Olofsson3,4, and H. E. Schwarz 1 University of Vienna, Department of Astronomy, Türkenschanzstrasse 17, 1180 Vienna, Austria e-mail: [email protected] 2 Nordic Optical Telescope, Apartado 474, 38700 Santa Cruz de La Palma, Spain 3 Department of Astronomy, Stockholm University, AlbaNova University Center, 10691 Stockholm, Sweden 4 Onsala Space Observatory, 43992 Onsala, Sweden Received 24 March 2011 / Accepted 25 May 2011 ABSTRACT Context. Previous studies on the stellar content of the two nearby dwarf galaxies NGC 147 and NGC 185 reveal a rich population of late-type giants in both systems, including a large number of carbon-rich objects. These stars are known to show pronounced photo- metric variability, which can be used for a more detailed characterisation of these highly evolved stars. Owing to their well-studied parameters, these Local Group members are ideal candidates for comparative studies. Aims. Through photometric monitoring, we attempt to provide a catalogue of long-period variables (LPVs), including Mira variables, semi-regular variables, and even irregular variables in NGC 147 and NGC 185. We investigate the light variations and compare the characteristics of these two LPV populations with the results found for other galaxies, such as the LMC. Methods. We carried out time-series photometry in the i-band of the two target galaxies with the Nordic Optical Telescope (NOT), covering a time span of ≈2.5 years. -
Astronomy Magazine Special Issue
γ ι ζ γ δ α κ β κ ε γ β ρ ε ζ υ α φ ψ ω χ α π χ φ γ ω ο ι δ κ α ξ υ λ τ μ β α σ θ ε β σ δ γ ψ λ ω σ η ν θ Aι must-have for all stargazers η δ μ NEW EDITION! ζ λ β ε η κ NGC 6664 NGC 6539 ε τ μ NGC 6712 α υ δ ζ M26 ν NGC 6649 ψ Struve 2325 ζ ξ ATLAS χ α NGC 6604 ξ ο ν ν SCUTUM M16 of the γ SERP β NGC 6605 γ V450 ξ η υ η NGC 6645 M17 φ θ M18 ζ ρ ρ1 π Barnard 92 ο χ σ M25 M24 STARS M23 ν β κ All-in-one introduction ALL NEW MAPS WITH: to the night sky 42,000 more stars (87,000 plotted down to magnitude 8.5) AND 150+ more deep-sky objects (more than 1,200 total) The Eagle Nebula (M16) combines a dark nebula and a star cluster. In 100+ this intense region of star formation, “pillars” form at the boundaries spectacular between hot and cold gas. You’ll find this object on Map 14, a celestial portion of which lies above. photos PLUS: How to observe star clusters, nebulae, and galaxies AS2-CV0610.indd 1 6/10/10 4:17 PM NEW EDITION! AtlAs Tour the night sky of the The staff of Astronomy magazine decided to This atlas presents produce its first star atlas in 2006. -
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). -
Corrugated Velocity Patterns in the Spiral Galaxies: NGC 278, NGC 1058, NGC 2500 & UGC 3574
Mem. S.A.It. Suppl. Vol. 25, 86 Memorie della c SAIt 2013 Supplementi Corrugated velocity patterns in the spiral galaxies: NGC 278, NGC 1058, NGC 2500 & UGC 3574 M. C. Sanchez´ Gil1, E. J. Alfaro2, and E. Perez´ 2 1 Universidad de Cadiz,´ Facultad de Ciencias Poligono Rio San Pedro 11510 - Puerto Real, Spain, e-mail: [email protected] 2 Instituto de Astrof´ısica de Andaluc´ıa (CSIC), E18008, Granada, Spain Abstract. In this work we address the study of the detection in Hα of a radial corruga- tion in the vertical velocity field in a sample of four nearly face-on, spiral galaxies. The geometry of the problem is a main criterion in the selection of the sample as well as of the azimuthal angle of the slits. These spatial corrugations must be equally associated with wavy vertical motions in the galactic plane with a strong large-scale consistency. Evidence of these kinematic waves were first detected in the analysis of the rotation curves of spiral galaxies (eg Vaucoleurs & de Vaucaleurs 1963, Pismis 1965), but it was not until 2001 that Alfaro et al. analyzed in more detail the velocity corrugations in NGC 5427 and a possi- ble physical mechanism for their origin. The aim of this study is to analyze the corrugated velocity pattern in terms of the star formation processes. We describe the geometry of the problem and establish its fundamental relationships. Key words. Techniques: spectroscopic–Galaxies: kinematics and dynamics - spiral - struc- ture 1. Introduction & Delgado 1992) and both in the azimuthal direction along different spiral arms (Spicker The disks of spiral galaxies are highly struc- & Feitzinger 1986), as in the radial, in differ- tured. -