The Harlow-Shapley Symposium on Globular
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Is the Universe Expanding?: an Historical and Philosophical Perspective for Cosmologists Starting Anew
Western Michigan University ScholarWorks at WMU Master's Theses Graduate College 6-1996 Is the Universe Expanding?: An Historical and Philosophical Perspective for Cosmologists Starting Anew David A. Vlosak Follow this and additional works at: https://scholarworks.wmich.edu/masters_theses Part of the Cosmology, Relativity, and Gravity Commons Recommended Citation Vlosak, David A., "Is the Universe Expanding?: An Historical and Philosophical Perspective for Cosmologists Starting Anew" (1996). Master's Theses. 3474. https://scholarworks.wmich.edu/masters_theses/3474 This Masters Thesis-Open Access is brought to you for free and open access by the Graduate College at ScholarWorks at WMU. It has been accepted for inclusion in Master's Theses by an authorized administrator of ScholarWorks at WMU. For more information, please contact [email protected]. IS THEUN IVERSE EXPANDING?: AN HISTORICAL AND PHILOSOPHICAL PERSPECTIVE FOR COSMOLOGISTS STAR TING ANEW by David A Vlasak A Thesis Submitted to the Faculty of The Graduate College in partial fulfillment of the requirements forthe Degree of Master of Arts Department of Philosophy Western Michigan University Kalamazoo, Michigan June 1996 IS THE UNIVERSE EXPANDING?: AN HISTORICAL AND PHILOSOPHICAL PERSPECTIVE FOR COSMOLOGISTS STARTING ANEW David A Vlasak, M.A. Western Michigan University, 1996 This study addresses the problem of how scientists ought to go about resolving the current crisis in big bang cosmology. Although this problem can be addressed by scientists themselves at the level of their own practice, this study addresses it at the meta level by using the resources offered by philosophy of science. There are two ways to resolve the current crisis. -
The Future of Spaceimaging
(NASA-CR-198818) THE FUTURE OF N95-31364 SPACE IMAGING. REPORT OF A COMMUNITY-BASED STUDY OF AN ADVANCED CAMERA FOR THE HUBBLE Unclas SPACE TELESCOPE Final Technical Report (Space Telescope Science Inst.) 150 p G3/89 0055789 TheFuture of SpaceImaging hen Lyman Spitzer first proposed a great, earth-orbiting telescope in I946, the nudear energy source of stars had been known for just six years. Knowledge of galaxies beyond our own and the understanding that our universe is expanding were only about twenty years of age in the human consciousness. The planet Pluto was seventeen. Quasars, black holes, gravitational lenses, and detection of the Big Bang were still in the future--together with much of what constitutes our current un- derstanding of the solar system and the cosmos beyond it. In I993, forty- seven years after it was conceived in a forgotten milieu of thought, the Hubble Space Telescope is a reality. Today, the science of the Hubble attests to the forward momentum of astronomical exploration from ancient times. The qualities of motion and drive for knowledge it exemplifies are not fixed in an epoch or a generation: most of the astronomers using Hubble today were not born when the idea of it was first advanced, and many were in the early stages of their education when the glass for its mirror was cast, The commitments we make today to the future of the Hubble observatory will equip a new genera- tion of young men and women to explore the astro- nomical frontier at the start of the 2I st century. -
Chapter I Review Papers Harlow Shapley
Chapter I Review Papers Harlow Shapley Downloaded from https://www.cambridge.org/core. IP address: 170.106.40.40, on 25 Sep 2021 at 08:30:59, subject to the Cambridge Core terms of use, available at https://www.cambridge.org/core/terms. https://doi.org/10.1017/S0074180900042340 Helen Sawyer Hogg and Willis Shapley remembering Willis Shapley fielding questions on his father Downloaded from https://www.cambridge.org/core. IP address: 170.106.40.40, on 25 Sep 2021 at 08:30:59, subject to the Cambridge Core terms of use, available at https://www.cambridge.org/core/terms. https://doi.org/10.1017/S0074180900042340 SHAPLEY'S DEBATE Michael Hoskin Cambridge University The attempt to make three-dimensional sense of the Milky Way goes back to a most unlikely origin: the English antiquary of the early eighteenth century, William Stukeley, remembered today for associating the Druids with Stonehenge. Stukeley came from Lincolnshire and so was a fellow-countryman of Isaac Newton, and as a result he was privileged to talk with the great man from time to time. In his Memoirs of Newton Stukeley records one conversation they had in about 1720, in which Stukeley proposed that the Sun and the brightest stars of the night sky make up what we today would term a globular cluster, and this cluster is surrounded by a gap, outside of which lie the small stars of the Milky Way in the form of a flattened ring. Stukeley's remarkable suggestion was recorded only in his manuscript memoirs, and had no effect on the subsequent history of astronomy. -
Our Milky Way.Key
Our Milky Way Learning Objectives ! What is the Milky Way? The Herschels thought we were at the center of our Galaxy...why were they wrong? ! How did Shapley prove we aren’t at the center? What are globular clusters? Cepheid Variable stars? ! How do we use Cepheid Variables to measure distance? ! What are the components of our Galaxy? What color are old stars? Young stars? Does our Galaxy get older or younger as you move out (i.e. from the disk to the halo)? ! How do we know our Galaxy is a spiral galaxy? ! Do stars in our Galaxy’s disk orbit as Kepler’s Laws would predict? What is a rotation curve? Why does our Galaxy’s rotation curve suggest dark matter exists? The Milky Way ! Our Galaxy is a collection of stars, nebulae, molecular clouds, and stellar remnants ! All bound together by gravity ! Connected by the stellar evolution cycle Determining the Shape of our Galaxy ! The number of 6400 ly stars were counted in all directions from 1300 ly the Sun by Sun Caroline Herschel and her brother William ! They assumed that all stars have the same brightness and that space contains no dust – these are incorrect assumptions ! They thus concluded that the Sun is at the center of the Universe - which is not true The Importance of Dust ! Dust dims and reddens starlight ! There is more dust toward the center of the Galaxy ! Consequence: We underestimate the number of stars in one direction ! We appear to be near the center, but we’re not Us Star Sun Can’t see stars here (if we’re looking for blue light from them) How Do We Find the Galactic Center? -
At the Harvard Observatory
Book Reviews 117 gravitational wave physicists, all of whom are members of an international group of over a thousand scientists engaged with the detection apparatus at two widely separated sites, one in Livingston, Louisiana and the other in Hanford, Washington. The emails research- ers in the collaboration exchanged and the queries Collins sent to the physicists who acted for him as “key informants” provide the bulk of the material for Collins’ “real- time” observations of this discovery in the making. At times, Collins finds the community of researchers exasperating and wrong-headed in their, in his view, overly secretive attitudes to their results. But Collins is not a detached witness of the events he describes and analyses. Instead, he is overall a highly enthusias- tic fan of the gravitational wave community. Collins has not sought out for Gravity’s Kiss the kinds of evidence one might have expected a historian to have pursued. Gravity’s Kiss, however, should be read on its terms. It is a work of reportage from an “embedded” sociologist of science with long experience of, and valuable connections in, the gravitational wave community. Along the way, he offers sharp insights into the work- ing of these scientists. Collins proves to be an excellent guide to the operations of a “Big Science” collaboration and the intense scrutiny of, and complicated negotiations around, the “[v]ery interesting event on ER8.” Robert W. Smith University of Alberta [email protected] “Girl-Hours” at the Harvard Observatory The Glass Universe: How the Ladies of the Harvard Observatory Took the Measure of the Stars. -
Astronomy HOMEWORK Chapter 15
Astronomy HOMEWORK Chapter 15 1. Where in the Galaxy is the solar system located? a. in the nucleus; b. in the halo; c. in a spiral arm; d. between two spiral arms; e. in the central bulge. d. between two spiral arms. Also, 26,000 LY from the center. 2. What is located in the nucleus of the Galaxy? a. a globular cluster; b. a spiral arm; c. a black hole; d. the solar system; e. a MACHO. c. a black hole. Of 4 million M⊙. 3. Which statement about the Milky Way Galaxy is correct? a. Our Galaxy is but one of many galaxies. b. Our Galaxy contains all stars in the universe. c. All stars in our Galaxy take the same time to complete one orbit. d. Most stars in our Galaxy are in the central bulge. e. None of the stars in our Galaxy move. a. Our Galaxy is but one of many [billions] of galaxies in the universe. 5. How did Edwin Hubble prove that M31 is not a nebula in our Milky Way Galaxy? M31 is the Andromeda Galaxy, called “Andromeda Nebula” at the time. Hubble identified several stars in M31 as Cepheid variables, and measured their pulsation periods and apparent brightness. He then used the known relationship between period and luminosity of Cepheid variables to determine their luminosity. Finally, he used the inverse square law to obtain their distance. Their distance put them many times farther away than the size of our Galaxy, which Shapley had determined in 1915. If they are farther away than the size of our Galaxy, they have to be outside it. -
Observational Cosmology - 30H Course 218.163.109.230 Et Al
Observational cosmology - 30h course 218.163.109.230 et al. (2004–2014) PDF generated using the open source mwlib toolkit. See http://code.pediapress.com/ for more information. PDF generated at: Thu, 31 Oct 2013 03:42:03 UTC Contents Articles Observational cosmology 1 Observations: expansion, nucleosynthesis, CMB 5 Redshift 5 Hubble's law 19 Metric expansion of space 29 Big Bang nucleosynthesis 41 Cosmic microwave background 47 Hot big bang model 58 Friedmann equations 58 Friedmann–Lemaître–Robertson–Walker metric 62 Distance measures (cosmology) 68 Observations: up to 10 Gpc/h 71 Observable universe 71 Structure formation 82 Galaxy formation and evolution 88 Quasar 93 Active galactic nucleus 99 Galaxy filament 106 Phenomenological model: LambdaCDM + MOND 111 Lambda-CDM model 111 Inflation (cosmology) 116 Modified Newtonian dynamics 129 Towards a physical model 137 Shape of the universe 137 Inhomogeneous cosmology 143 Back-reaction 144 References Article Sources and Contributors 145 Image Sources, Licenses and Contributors 148 Article Licenses License 150 Observational cosmology 1 Observational cosmology Observational cosmology is the study of the structure, the evolution and the origin of the universe through observation, using instruments such as telescopes and cosmic ray detectors. Early observations The science of physical cosmology as it is practiced today had its subject material defined in the years following the Shapley-Curtis debate when it was determined that the universe had a larger scale than the Milky Way galaxy. This was precipitated by observations that established the size and the dynamics of the cosmos that could be explained by Einstein's General Theory of Relativity. -
Women in Astronomy: an Introductory Resource Guide
Women in Astronomy: An Introductory Resource Guide by Andrew Fraknoi (Fromm Institute, University of San Francisco) [April 2019] © copyright 2019 by Andrew Fraknoi. All rights reserved. For permission to use, or to suggest additional materials, please contact the author at e-mail: fraknoi {at} fhda {dot} edu This guide to non-technical English-language materials is not meant to be a comprehensive or scholarly introduction to the complex topic of the role of women in astronomy. It is simply a resource for educators and students who wish to begin exploring the challenges and triumphs of women of the past and present. It’s also an opportunity to get to know the lives and work of some of the key women who have overcome prejudice and exclusion to make significant contributions to our field. We only include a representative selection of living women astronomers about whom non-technical material at the level of beginning astronomy students is easily available. Lack of inclusion in this introductory list is not meant to suggest any less importance. We also don’t include Wikipedia articles, although those are sometimes a good place for students to begin. Suggestions for additional non-technical listings are most welcome. Vera Rubin Annie Cannon & Henrietta Leavitt Maria Mitchell Cecilia Payne ______________________________________________________________________________ Table of Contents: 1. Written Resources on the History of Women in Astronomy 2. Written Resources on Issues Women Face 3. Web Resources on the History of Women in Astronomy 4. Web Resources on Issues Women Face 5. Material on Some Specific Women Astronomers of the Past: Annie Cannon Margaret Huggins Nancy Roman Agnes Clerke Henrietta Leavitt Vera Rubin Williamina Fleming Antonia Maury Charlotte Moore Sitterly Caroline Herschel Maria Mitchell Mary Somerville Dorrit Hoffleit Cecilia Payne-Gaposchkin Beatrice Tinsley Helen Sawyer Hogg Dorothea Klumpke Roberts 6. -
Cosmic Search Issue 06 Page 32
North American AstroPhysical Observatory (NAAPO) Cosmic Search: Issue 6 (Volume 2 Number 2; Spring (Apr., May, June) 1980) [Article in magazine started on page 32] ABCs of Space By: John Kraus A. How Do You Harness a Black Hole? Nowadays universities have astronomy departments, aeronautical engineering departments and even astronautical engineering departments. As yet, however, I am not aware of any astro-engineering departments. But some day there may be and what kind of courses might be offered? Probably ones on the mining of asteroids, construction of space habitats and even possibly one on "Harnessing of Black Holes." A first consideration regarding the last item would be data on critical distances and strategies on how to approach a black hole without falling in. A second consideration would be a discussion of how a black hole is a potential source of great amounts of energy if you go at it right. And finally, the instructor would probably get down to the details of the astroengineering required with blueprints of a design and calculations of the expected power generating capability. This may sound a bit futuristic and it is, but the famous text "Gravitation" by Charles Misner, Kip Thorne and John Wheeler includes a hypothetical example about how an advanced civilization could construct a rigid platform around a black hole and build a city on the platform. The discussion goes on to say that every day garbage trucks carry a million tons of garbage collected from all over the city to a dump point where the garbage goes into special containers which are then dropped one after the other down toward the black hole at the center of the city. -
Discoveries 1917 100” Hooker Telescope on Mt
Discoveries 1917 100” Hooker telescope on Mt. Wilson 1920 “Debate on the Scale of the Universe” Interpretaon of the “Spiral Nebulae” Harlow Shapley “only gas clouds” within a single galacc Universe Sun far from the center Heber CurGs Sun at the center of our relavely small galaxy all the spiral nebulae are other galaxies Measure the size – HOW?? Fall 2018 1 Yardstck 1.Brightness (magnitude) 2.Parallax 3.Cepheid Variables November 23, 1924 Edwin Hubble, 35, published in the New York Times his discovery that there were many galaxies further away from the Milky Way. Fall 2018 2 MMilkyilky Way 1838 Discovery of stellar parallax 1838 Discovery of stellar parallax (F.Bessel) ) 1 1 1 Parsec = Parsec = = = 3.263.26 ly P (arcsec) (arcsec) 1 1 Mpc = 10= 106 parsecs = 3.26 million lightyears parsecs = 3.26 million lightyears Fall 2018 Fall 2018 213 Cepheid Variables At Harvard (Society For the Collegiate InstrucGon of Women) Oberlin and Radcliff Colleges she was capGvated by Astronomy. Variable stars vary periodically in brightness HenrieUa LeaviU HenrieUa found ~50) Cepheid variables Fall 2018 4 Edwin Hubble ! Confirmed the extra galacGc nature of nebulae using Cepheid variable yardsGck ! Observed that every galaxy appears to be moving away from every other one Farthest ones moving faster Fall 2018 5 Velocit measurement Doppler Effect Aer Einstein Fall 2018 6 Speed vs. Distance Fall 2018 7 Hubble Constant Not constant! Fall 2018 8 What is going on? Q1 Moving away? – the track back and find where they started Finally Copernicus is verified – we are not -
Assessment of Options for Extending the Life of the Hubble Space Telescope
PREPUBLICATION COPY Subject to Further Editorial Correction Assessment of Options for Extending the Life of the Hubble Space Telescope Final Report Committee on the Assessment of Options for Extending the Life of the Hubble Space Telescope Space Studies Board Aeronautics and Space Engineering Board Division on Engineering and Physical Sciences THE NATIONAL ACADEMIES PRESS Washington, D.C. www.nap.edu THE NATIONAL ACADEMIES PRESS 500 Fifth Street, N.W. Washington, DC 20001 NOTICE: The project that is the subject of this report was approved by the Governing Board of the National Research Council, whose members are drawn from the councils of the National Academy of Sciences, the National Academy of Engineering, and the Institute of Medicine. The members of the committee responsible for the report were chosen for their special competences and with regard for appropriate balance. Support for this project was provided by Contract NASW 01001 between the National Academy of Sciences and the National Aeronautics and Space Administration. Any opinions, findings, conclusions, or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of the sponsors. Cover: International Standard Book Number 0-309-XXXXX-0 (Book) International Standard Book Number 0-309-XXXXX-0 (PDF) Copies of this report are available free of charge from Space Studies Board National Research Council The Keck Center of the National Academies 500 Fifth Street, N.W. Washington, DC 20001 Additional copies of this report are available from the National Academies Press, 500 Fifth Street, N.W., Lockbox 285, Washington, DC 20055; (800) 624-6242 or (202) 334-3313 (in the Washington metropolitan area); Internet, http://www.nap.edu. -
How Telescopes Changed Our Understanding of Our Universe - Suggested Script PRESENTATION NOTE: This Presentation Can Take 45 Minutes to an Hour
- How Telescopes Changed our Understanding of our Universe - Suggested Script PRESENTATION NOTE: This presentation can take 45 minutes to an hour. To shorten it, you may want to allow your audience to vote on the three or four questions they would like discussed. See Slide 3 for the questions covered in this presentation. 1. 400 years ago, before telescopes, our understanding of the universe was very different. This is what was believed: We live on a spherical ball orbited by the rest of a finite, spherical universe. Earth does not move. It is the center of the universe. Our Sun orbits the Earth, as do all the other planets and the Moon. The stars are distant objects, always perfect and unchanging. How did telescopes & associated technologies unlock the secrets of the universe and help us toward the understanding we have today where Earth is no longer at the center of the universe? Instead, we know that ours is a small planet orbiting a star in the suburbs of a large galaxy filled with billions of other stars and planets, surrounded by billions of other galaxies becoming increasingly ever distant from each other by the expansion of space. This is the story of how telescopes continuously changed our understanding of the universe and our place in it - transforming our view of our universe. And we still have much more to discover! 2. Before telescopes, we could only use our eyes and a variety of measuring instruments to plot the positions and movements of objects in the sky to create a limited understanding of our universe.