The Story of Starlight: Women Who Changed Our Understanding of the Universe
Total Page:16
File Type:pdf, Size:1020Kb
Load more
Recommended publications
-
Astronomy 142, Spring 2013 2 April 2013
Astronomy 142, Spring 2013 2 April 2013 Today in Astronomy 142: distances to the galaxies Standard candles and standard rulers. Cepheids, and Henrietta Leavitt’s invention of standard candles. The extragal acti c nature of the spiral nebulae and the Shapley-Curtis debate. Type Ia supernovae as standard candles. The extragalactic distance The Small Magellanic Cloud, site of the scale. discovery of Leavitt’s Law. (Photograph by Weihao Wang (NRAO).) 2 April 2013 Astronomy 142, Spring 2013 1 Standard candles and standard rulers There’s only one direct distance measurement method for individual objects more than a few light-hours away – trig parallax – and it only works on objects within a few hundred parsecs, these days. (> 10 kpc, after Gaia is deployed.) Distance being key, astronomers have often sought standard candles or rulers to aid in its determination. Standard candle: an object with a well-determined luminosity L known a priori, whose distance is therefore rLf4(or equivalently 5log r10 pc mM ) . Standard ruler: an object with length d perpendicular to the line of sight is known a priori, whose distance is rdsin d . 2 April 2013 Astronomy 142, Spring 2013 2 Henrietta Leavitt and standard candles Today tens of thousands of Cepheid variable stars are known, a large fraction of which – about 2400 – were discovered by Henrietta Leavitt, perhaps the most illustrious of the women Henrietta Swan Leavitt (AIP photo) who worked as “computers” in Edward Pickering’s group at Harvard College Observatory. 969 of them are in the Small Magellanic Cloud (Leavitt 1908), and therefore all about the same distance (~60 kpc). -
AAS NEWSLETTER Issue 127 a Publication for the Members of the American Astronomical Society
October 2005 AAS NEWSLETTER Issue 127 A Publication for the members of the American Astronomical Society PRESIDENT’S COLUMN know that Henrietta Swan Leavitt measured the Cepheid variable stars in the Magellanic Clouds Robert Kirshner, [email protected] to establish the period-luminosity relation, and that Inside this rung on the distance ladder let Hubble reach As I write this, summer is definitely winding down, M31 and other nearby galaxies. And I recognized George Johnson’s name from his thoughtful pieces 3 and the signs of Fall on a college campus are all in the New York Times science pages. Who Served Us Well: around: urgent overtime work on the last licks of John N. Bahcall summer renovations is underway, vast piles of trash and treasure from cleaning out dorm rooms are But I confess, though I walk on the streets where accumulating, with vigorous competitive double- she lived, work in a building connected by a 5 parking of heavily-laden minivans just ahead. With labyrinth to the one she worked in, and stand on Katrina Affected the Galaxy overhead most of the night, and the the distance ladder every day, my cerebral cortex Physics and summer monsoon in progress in Arizona, the pace is a little short on retrievable biographical details Astronomy (KAPA) of supernova studies slackens just a bit (for me, for Henrietta Swan Leavitt. Johnson has plumbed Community Bulletin anyway) and I had time to do a little summer reading. the Harvard archives, local census records, and the correspondence of Harvard College Board There were too many mosquitoes in Maine to read in a hammock, but there was enough light on the Observatory Directors to give us a portrait of screened porch. -
Selected Highlights of Women's History
Selected Highlights of Women’s History United States & Connecticut 1773 to 2015 The Permanent Commission on the Status of Women omen have made many contributions, large and Wsmall, to the history of our state and our nation. Although their accomplishments are too often left un- recorded, women deserve to take their rightful place in the annals of achievement in politics, science and inven- Our tion, medicine, the armed forces, the arts, athletics, and h philanthropy. 40t While this is by no means a complete history, this book attempts to remedy the obscurity to which too many Year women have been relegated. It presents highlights of Connecticut women’s achievements since 1773, and in- cludes entries from notable moments in women’s history nationally. With this edition, as the PCSW celebrates the 40th anniversary of its founding in 1973, we invite you to explore the many ways women have shaped, and continue to shape, our state. Edited and designed by Christine Palm, Communications Director This project was originally created under the direction of Barbara Potopowitz with assistance from Christa Allard. It was updated on the following dates by PCSW’s interns: January, 2003 by Melissa Griswold, Salem College February, 2004 by Nicole Graf, University of Connecticut February, 2005 by Sarah Hoyle, Trinity College November, 2005 by Elizabeth Silverio, St. Joseph’s College July, 2006 by Allison Bloom, Vassar College August, 2007 by Michelle Hodge, Smith College January, 2013 by Andrea Sanders, University of Connecticut Information contained in this book was culled from many sources, including (but not limited to): The Connecticut Women’s Hall of Fame, the U.S. -
Student Exploration: Big Bang Theory – Hubble's
McCarthy Physical Science 2017 Name: Date: Student Exploration: Big Bang Theory – Hubble’s Law Vocabulary: absolute brightness, absorption spectrum, apparent brightness, Big Bang theory, blueshift, Cepheid variable, Doppler shift, Hubble constant, Hubble’s law, luminosity, megaparsec, period, redshift, spectrograph Prior Knowledge Questions (Do these BEFORE using the Gizmo.) Standing by the side of a lonely highway at night, you see two motorcycle headlights, one in each direction. The headlight on your left appears brighter than the one on your right. 1. If the headlights are equally bright, which motorcycle is closer? Explain: 2. Suppose the dim-looking headlight on the right is actually a small light on the front of a bicycle. What can you conclude about the distance of the motorcycle and bicycle? Gizmo Warm-up In 1912, an astronomer named Henrietta Swan Leavitt studied a class of stars called Cepheid variables. These stars change from bright to dim to bright again. Her discoveries led to a method of measuring distances to other galaxies and eventually helped to support the Big Bang theory of the origin of the universe. In the Big Bang Theory – Hubble’s Law Gizmo™, select Region A. Look at the image of the Andromeda Galaxy, a galaxy relatively close to our own Milky Way galaxy. 1. Locate the two Cepheid variables, the stars that change in brightness over time. Star A-091 is the yellow star, and A-171 is the white star. A. Which star reaches a greater apparent brightness? B. Which star takes longer to pulse? 2. Because both stars are in the same galaxy, they are about the same distance from Earth. -
The Hidden History of Women in Astronomy
The Hidden History of Women in Astronomy Michael McEllin 1 Introduction What is the Sun made of? One hundred years ago our physical samples consisted of the Earth itself and a few meteorites, mostly rocky, with a few metallic and some rare `carbonaceous' examples containing volatiles. Fur- thermore, spectral lines in the Sun's light showed that many of the chemical elements discovered on the Earth were indeed also present on the Sun. Why would you believe that its composition was radically different to the Earth's, especially when the prevailing theories of Solar System origin had them be- ing formed from the same primeval stuff? There was even a just about tenable theory that the steady accretion of meteorites onto the Solar surface might release enough gravitational energy to keep it hot. What alternative was there? Sir Arthur Eddington had indeed speculated that Einstein's E = MC2 hinted at the possibility of extraordinary energy sources that might power the sun but we were still a decade away from understanding nuclear fusion reactions: Eddington's speculation may have been inspired but it was still vague speculation. Spectral lines were, in fact, still something of a mystery. We did not know why some spectral lines were so much more prominent than others or why some expected lines failed to appear at all. Until Bohr's model of the atom in 1913 we had no understanding at all of the origin of spectral lines, and there were clearly many missing bits of the puzzle. If you do not fully understand why lines look the way they do line how can you be certain you understand the conditions in which they form and relatively abundances of the contributing chemical elements? Atomic spectra began to be really understood only after 1925, when the new `Quantum Mechanics', in the form of Schr¨odinger'sequation, Heisen- berg's Matrix Mechanics and Dirac's relativistic theory of the electron re- placed the `Old Quantum Theory'. -
Maria Mitchell's Legacy to Vassar College: Then And
Library and Information Services in Astronomy IV July 2-5, 2002, Prague, Czech Republic B. Corbin, E. Bryson, and M. Wolf (eds) Maria Mitchell's Legacy to Vassar College: Then and Now Flora Grabowska Vassar College Libraries, Poughkeepsie, NY 12604, USA fl[email protected] Abstract. Maria Mitchell became Vassar's first Astronomy Professor and Observatory Director in 1865. Her teaching emphasis on students learning by direct observation and analysis is continued today at Vassar College. Several of her students went on to prominence in astronomy, two of them succeeding her at Vassar. Astronomy majors today, both male and female, consistently achieve success after Vassar, in astronomy as well as in other fields. She encouraged her students to present their findings at scientific meetings and in scientific journals, also encouraged today as undergraduates co-author research papers with faculty members. She insisted on excellent facilities and built up the library collection, maintained today to a standard remarkable for a college of just under 2,500 undergraduate students. 1. Great Beginnings Matthew Vassar was keen to have female teachers at Vassar College (Haight 1916). Maria Mitchell had achieved world fame with her 1847 telescopic discov- ery of a comet and was an excellent choice, becoming Vassar's first astronomy professor in 1865. In a eulogy at her funeral in 1889, Vassar College President Taylor concluded, \She has been an impressive figure in our time, and one whose influence lives." (Taylor 1889) Henry Albers, Vassar's fifth Observatory director (the first male!), referring to our fine facilities today, wrote, \In keeping with the legacy of Maria Mitchell, these facilities enable today's students to learn and apply the most modern astronomical techniques." (Albers 2001, 329) This presentation aims to confirm that the legacy has been self-perpetuating and lives on. -
Curriculum Vitae
CURRICULUM VITAE Smadar Naoz September 2021 Contact University of California Los Angeles, Information Department of Physics & Astronomy 30 Portola Plaza, Box 951547 E-mail: [email protected] Los Angeles, CA 90095 WWW: http://www.astro.ucla.edu/∼snaoz/ Research Dynamics of planetary, stellar and black hole systems, which include formation of Hot Jupiters, Interests globular clusters, spiral structure, compact objects etc. Cosmology, structure formation in the early Universe, reionization and 21cm fluctuations. Education Tel Aviv University, Tel Aviv, Israel Ph.D. in Physics, January 2010 Hebrew University of Jerusalem, Jerusalem, Israel M.S. in Physics, Magna Cum Laude, 2004 B.S. in Physics 2002 Positions University of California, Los Angeles Associate professor since July 2019 Howard & Astrid Preston Term Chair in Astrophysics since July 2018 Assistant professor 2014-2019 Harvard Smithsonian CfA, Institute for Theory and Computation Einstein Fellow, September 2012 { June 2014 ITC Fellow, September 2011 { August 2012 Northwestern University, CIERA Gruber Fellow, September 2010 { August 2011 Postdoctoral associate in theoretical astrophysics, January 2010 { August 2010 Scholarships Helen B. Warner Prize, awarded by the American Astronomical Society, 2020 Honors and Scialog fellow, and accepted proposal, Signatures of Life in the Universe, 2020/2021 (conference Awards postponed to 2021 due to COVID-19) Career Commitment to Diversity, Equity and Inclusion Award, given by UCLA Academic Senate 2019. For other diversity awards, see xDEI. Hellman Fellows Award, awarded by Hellman Fellows Program, aimed to support the research of promising Assistant Professors who show capacity for great distinction in their research, June 2017 Multiple departmental teaching awards 2015-2019, see xTeaching, for details Sloan Research Fellowships awarded by the Alfred P. -
Women Who Read the Stars Sue Nelson Delights in Dava Sobel’S Account of a Rare Band of Human Computers
Some of the Harvard Observatory ‘computers’ in 1925. Annie Jump Cannon is seated fifth from left; Cecilia Payne is at the drafting table. HISTORY Women who read the stars Sue Nelson delights in Dava Sobel’s account of a rare band of human computers. here are half a million photographic magnitude, on the as computers at Harvard, a practice unique plates in the Harvard College Observa- photographic plates to the university. Within five years, the num- tory collection, all unique. They date to and computing its ber of paid female computers, from a range Tthe mid-1880s, and each can display the light location in the sky. of backgrounds, had risen to 14. Their efforts from 50,000 stars. These fragments of the Pickering was espe- would be boosted by philanthropist Cath- cosmos furthered our understanding of the cially interested in erine Wolfe Bruce, who in 1889 donated Universe. They also reflect the dedication and variable stars, whose US$50,000 to the observatory, convinced intelligence of extraordinary women whose light would brighten that the introduction of photography and stories are more than astronomical history: and fade over a spe- spectroscopy would advance the field. ARCHIVES UNIV. HARVARD COURTESY they reveal lives of ambition, aspiration and cific period. These The Glass The Glass Universe concentrates on a few of brilliance. It takes a talented writer to inter- fluctuations, captured Universe: How the Harvard computers. Williamina Fleming, weave professional achievement with per- on the plates, required the Ladies of a Scottish school teacher, arrived at the obser- sonal insight. By the time I finished The Glass constant observation, the Harvard vatory in 1879, pregnant and abandoned by Universe, Dava Sobel’s wonderful, meticulous but he couldn’t afford Observatory Took her husband. -
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. -
Antonia Maury, Clasificadora De Estrellas (1866-1952, Estados Unidos)
Antonia Maury, clasificadora de estrellas (1866-1952, Estados Unidos) Antonia Maury fue una astrónoma importante de finales del siglo XIX. Fue una de las primeras mujeres en publicar un trabajo sobre estrellas con su propio nombre. Sus estudios sirvieron para crear el diagrama HR, el diagrama más importante de la astrofísica estelar. Nació en 1866 en Cold Spring, Nueva York, dentro de una familia acomodada de origen portugués. Su abuelo y su tío materno eran dos astrónomos muy reputados: John William Draper y Henry Draper. Así, Maury y sus hermanos crecieron muy familiarizados con la ciencia desde pequeños. Antonia aspiró a ser astrónoma, y se graduó del Vassar College con una matrícula de honor en astronomía, física y filosofía en 1887. Su mentora fue otra astrónoma importante de la época: Maria Mitchell. En 1887 comenzó a trabajar en el Observatorio de Harvard, y entró a formar parte del grupo de mujeres computadoras de Harvard, un grupo de astrónomas encargadas de la clasificación de las estrellas bajo la dirección de Edward Pickering. Allí se encontró con otros astrónomas importantes de la época: Henrietta Swan Leavitt, Annie Jump Cannon y Williamina Fleming. Maury comenzó determinando el periodo orbital de varias estrellas binarias que giran la una alrededor de la otra, y luego se puso a clasificar estrellas según su espectro. Ahora bien, muy pronto comenzó a tener discrepancias con Pickering, tanto por el sistema de trabajo como el de clasificación estelar. Debido a estas discrepancias con el director, en 1896 dejó el observatorio y fue a trabajar a la escuela Miss Masson de Nueva York dando clases de astronomía y también se encargó de la gestión del Draper Park Museum.