Magellanic Cloud Concepts

The Glass Universe: How the Ladies of the Harvard Observatory Took the Measure of the Stars

by Dava Sobel · 6 Dec 2016 · 442pp · 110,704 words

southern night sky. Astronomers who later resolved the clouds into star clusters still called them by Magellan’s name. In early 1905, in the Small Magellanic Cloud alone, Miss Leavitt uncovered nine hundred new variables. “What a variable-star ‘fiend’ Miss Leavitt is,” Charles Young of Princeton wrote in awe to Pickering

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comprehensive, concentrated on the variable stars of long period. It did not include the multitude of short-period variables Miss Leavitt had uncovered in the Magellanic Clouds. Those required a separate treatment, currently nearing completion by Miss Leavitt herself. “It may be asked,” Solon Bailey wrote in an article for Popular Science

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of the sky in 1908, maintaining her lead over Miss Cannon and Miss Leland by a wide margin. She also published her findings about the Magellanic Clouds. Through careful comparisons of many plates, she had observed the range of maximum to minimum brightness for all 1,777 of her variables, and listed

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taken within two to three days of each other in 1905 had alerted Miss Leavitt to the untold number of quick-change stars in the Magellanic Clouds. • • • MISS LEAVITT HAD BEEN CALLED HOME AGAIN to Wisconsin after her father died on March 4, 1911, and she spent the spring and summer helping

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-Hudson. Resuming the hunt for new variable stars on the Harvard sky maps, Miss Leavitt continued to ponder the thousands she had encountered in the Magellanic Clouds. The prevalence of variables in those two southern star Clouds beggared all comparison. Miss Leavitt had tallied more than nine hundred in the Small Cloud

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, denied such intimacy with the heavens, could only imagine herself standing agape in the Andes, under the southern meanders of the Milky Way, watching the Magellanic Clouds trail after the star stream like a pair of lost sheep. Bailey believed the two Clouds to be unique structures, separate from the Milky Way

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white nebulous objects scattered through space were also separate star systems, independent of the Milky Way. Bailey’s two- and four-hour exposures of the Magellanic Clouds, taken with the Bruce telescope, had revealed crowds of stars as faint as seventeenth magnitude. Miss Leavitt picked her way among them in her initial

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, since most of them remained at their dimmest most of the time, brightening suddenly in short bursts. In her 1908 publication, “1777 Variables in the Magellanic Clouds,” she gauged all the ranges of magnitude and gave the maximum and minimum value for every star, as best she could. She traced the complete

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Observatory Circular on March 3, 1912. He used the word “law” to describe the finding she had demonstrated for twenty-five stars in the Small Magellanic Cloud: The brighter the magnitude, the longer the period. It meant that certain types of variables telegraphed their true magnitudes in the duration of their light

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. These stars shone many orders of magnitude brighter than their peers of the same period among Miss Leavitt’s stars. The differences put the Small Magellanic Cloud, by Hertzsprung’s reckoning, at a distance of thirty thousand light-years—a chasm so great as to strain credulity. Henry Norris Russell followed some

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-type variable stars, thanks to the period-luminosity relation. In so doing, he had assumed that Miss Leavitt’s law was not limited to the Magellanic Clouds, but could govern conditions anywhere. To place the clusters not containing Cepheids, Shapley combined a variety of means and assumptions to leapfrog his way across

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the most important photometric work that can be done on Cepheid variables at the present time is a study of the Harvard plates of the Magellanic clouds. Probably Miss Leavitt’s many other problems have interrupted and delayed her work on the variables of the clouds for the interval of six or

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1918, filled the known universe. It was so immense that it subsumed everything else: globular clusters rimmed it, nebulous forms fit inside it, and the Magellanic Clouds hung from it as appendages. But numerous astronomers refused to be bound by it. Unlike Shapley, they viewed the Milky Way as one galaxy among

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Arville “Billy” Walker to assist him with his correspondence. He straightaway engaged Miss Leavitt in a study of the different types of variables in the Magellanic Clouds. Together they demonstrated that the Clouds contained short-period, cluster-type variables, in addition to Cepheids. This was just the confirmation Shapley needed to shore

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physicians and the help of a maidservant. He sent reports of Ruth’s convalescence north, along with the plates he continued making of the Large Magellanic Cloud. Shapley, sympathetic to the couple’s plight, sought to relieve them of responsibility at Arequipa, and looked to Edward King and his wife, Kate, as

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countryman Henri Becquerel, the discoverer of radioactivity. Shapley responded to Mittag-Leffler on March 9: “Miss Leavitt’s work on the variable stars in the Magellanic Clouds, which led to the discovery of the relation between period and apparent magnitude, has afforded us a very powerful tool in measuring great stellar distances

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cousins Harriet and Dorothy Catherine. The woman in the dark dress is unidentified. Stars appear as black dots in this negative plate of the Small Magellanic Cloud, a satellite galaxy of the Milky Way that can be seen from the Southern Hemisphere. The splotch at right is the dense globular cluster of

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Cushman. At her right is Annie Cannon, and Evelyn Leland is in the back row between them. This two-hour-long exposure of the Large Magellanic Cloud, taken with the 8-inch Bache telescope at Arequipa on January 23, 1897, gave the staff in Cambridge hundreds of objects to number and ponder

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as a full-time employee Edward Pickering issues “Photographic Map of the Entire Sky.” 1905 Henrietta Leavitt notices an inordinate number of variables in the Magellanic Clouds. Edward Pickering elected president of the Astronomical and Astrophysical Society of America. 1906 Edward Pickering and Henrietta Leavitt embark on a large-scale determination of

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a whole-sky catalogue of 263 bright clusters and nebulae in the Annals, vol. 60 Henrietta Leavitt publishes her discovery of “1777 Variables in the Magellanic Clouds” in the Annals, vol. 60 Edward Pickering receives the Catherine Wolfe Bruce Gold Medal. 1909 Solon Bailey reconnoiters potential new observatory sites in South Africa

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members’ published articles in professional journals. 1924 Harlow Shapley issues the first in a series of papers detailing the distance, size, and structure of the Magellanic Clouds. Ninth volume of the Henry Draper Memorial is published in the Annals, vol. 99. 1925 Harlow Shapley introduces a new publication series of books, the

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body’s) changing brightness over time. Luminosity The intrinsic brightness of a star, or the total amount of energy it emits per unit of time. Magellanic Clouds Two dense conglomerations of stars and nebulae seen from the Southern Hemisphere, now known to be satellite galaxies of the Milky Way. Magnitude The brightness

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with the Leiden Observatory in the Netherlands, was first to seize on Henrietta Leavitt’s period-luminosity relation to measure the distance to the Small Magellanic Cloud. He uncovered the existence of both giant and dwarf red stars, demonstrated the variability of Polaris (the North Star), and helped chart the general course

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, 1900–May 4, 1989), a 1923 Vassar alumna, delayed the start of her graduate studies till 1924 because of illness. At Harvard she studied the Magellanic Clouds, but returned to Vassar in 1925 as a physics instructor, then married accountant Hubert Stanley Russell in 1927. Anna Winlock (September 15, 1857–January 3

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–15, 275, 276 honors and tributes, 171, 210–11 and observatory directorship, 183 personal life, 131, 134, 150, 170, 183 work of: Orion Nebula and Magellanic Clouds research, 113–15, 125, 149–53, 276; period-luminosity relation discovery, 130–31, 151–52, 170–71, 210–11, 261–62, 277, 288–89; photometric

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luminosity indicators, 252–53 See also absolute magnitude; period-luminosity relation M-42. See Orion Nebula McAteer, Charles, 149 McCarthy, Joseph, 254 Mackie, Joan, 171 Magellanic Clouds, 150–51, 153, 282 variable star discoveries in, 114–15, 125, 130–31, 149–53, 276 See also Cepheid variables magnitude (of stars), 11, 282

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, 255, 258, 279, 289 meteors and meteor research, 187–88, 254, 255, 273, 282 Milky Way, 37, 150–51, 282 interstellar absorption in, 227–28 Magellanic Clouds and, 150–51 Shapley’s work and related galactic theories, 182, 184–88, 190, 198, 204–6, 211, 222–23, 228, 233, 262 Milne, Edward

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seeing (viewing conditions), 45, 132, 283 Boyden Station conditions, 45, 131, 132–33, 202, 219–20 at Cambridge site, 67–68 “1777 Variables in the Magellanic Clouds” (Leavitt), 151, 276 Shapley, Harlow, 291 ant studies, 169–70, 196 astronomy research and theories, 285; catalogue of nebulae, 219, 233; cluster variable research, 161

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of Variable Star Observers; Cepheid variables; Harvard Photometry; specific stars, observers, and analysts variable stars: Chandler’s catalogues, 60, 111 Harvard catalogue, 97, 111 in Magellanic Clouds, 114–15, 125, 130–31, 149–53, 276 naming conventions, 297 novae as, 57–58 number known, 48, 278 periods of, 283 types and classification

Coming of Age in the Milky Way

by Timothy Ferris · 30 Jun 1988 · 661pp · 169,298 words

a telescope are rare; the next one after the seventeenth century did not come until 1987, when a blue giant star exploded in the Large Magellanic Cloud, a neighboring galaxy to the Milky Way, to the delight of astronomers in Australia and the Chilean Andes. The two Supernovae that graced the Renaissance

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familiarity with the southern sky. She happened to be assigned to a region that includes the Magellanic Clouds. So named because they attracted the attention of Magellan and his crew on their voyage around the world, the Magellanic Clouds are two large, shaggy patches of softly glowing light that resemble detached swatches of the

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fireflies in a bottle viewed from across a field at night. This means that any significant difference in the apparent magnitudes of stars in a Magellanic Cloud must result from genuine differences in their absolute magnitudes and not from the effect of differing distances. Thanks to this happy circumstance, Leavitt in studying

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Cepheid variable stars in the Magellanic Clouds was able to notice a correlation between their brightness and their period of variability—the brighter the Cepheid, the longer its cycle of variation. The

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are. Moreover, he assumed that the Cepheid variable stars he observed in globular clusters were essentially identical to those Henrietta Leavitt had found in the Magellanic Clouds; actually, as Walter Baade and other astrophysicists were to find, the cluster variables are less massive and intrinsically less bright, and therefore by implication less

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, as the back-blowing veils of froth that whitecap the waves of earthly oceans. Beyond the Milky Way lie more galaxies. Some, like the Large Magellanic Cloud and the Andromeda galaxy, are spirals. Others are ellipticals, their stars hung in pristine, cloudless space. Others are dim dwarfs, some not much larger than

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and metal that had been assembled to look for proton decay. This came in handy in 1987, when a supernova blazed forth in the Large Magellanic Cloud and a wave of neutrinos was promptly detected at the Kamioka and Lake Erie proton-decay installations. The observation confirmed a theory (authored in part

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universe. Though unproved and perhaps unprovable, Mach’s principle inspired Einstein, who sought with partial success to incorporate it into the general theory of relativity. Magellanic Clouds. Two galaxies that lie close to the Milky Way galaxy. They are visible in the southern skies of Earth. Magnetic monopole. A massive particle with

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all four forces. Time: 1987 Noteworthy Events: Proton-decay experiments in the United States and Japan detect neutrinos broadcast by a supernova in the Large Magellanic Cloud, ushering in the new science of observational neutrino astronomy. Time: 1988 Noteworthy Events: Quasars are detected near the outposts of the observable universe; their redshifts

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Koran, the, 43 Lamarck, Jean-Baptiste de, 236 Lamarckism, 236 Lambert, Johann Heinrich, 144, 149–150, 161 Laplace, Pierre-Simon de, 161, 290–291 Large Magellanic Cloud, 70, 175, 327 Law of falling bodies, 84, 90–94 Law of universal gravitation, 81 Laws of thermodynamics, 247 Lead, 279 Leavitt, Henrietta Swan, 169

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Lyell, Charles, 217, 225, 226–229 Darwin and, 229, 231, 232, 239, 242, 243, 244 Mach, Ernst, 190–191, 386 Magellan, Ferdinand, 48, 56n, 59 Magellanic Clouds, 70, 169–170, 171, 175, 327 Magnesium, 165, 272 Magnetic monopoles, 356–357 Malthus, Thomas, 237 Many body problem, 121 Mars, 117 Kepler’s study

The Milky Way: An Autobiography of Our Galaxy

by Moiya McTier · 14 Aug 2022 · 194pp · 63,798 words

’m better than dwarf galaxies just because of my size. There are some galaxies right on the cusp between dwarf and not, like the Large Magellanic Cloud, whom I know better as Larry. The two of us have our disagreements, and I am the objectively better galaxy, but it’s not because

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’t give away too much of that story just yet. That leaves Larry, Sammy, and Trin, or as you probably know them, the Large Magellanic Cloud, the Small Magellanic Cloud, and Triangulum. “Friends” is possibly too strong a word, and not always accurate. Do you have a word for a being whose presence you

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body. But I’ve gotten ahead of myself. I haven’t even properly introduced you to Sammy yet. You might know Sammy as the Small Magellanic Cloud, and perhaps you’ve even seen the blurry smudge in your night sky if you live near your planet’s southern hemisphere. Sitting just two

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the sixteenth century—because apparently you ignore the forty-five million centuries that came before it—that humans started calling them the Small and Large Magellanic Clouds after some blowhard named Magellan saw them while he sailed around the globe. For better or worse, those are the companions the universe has provided

Day We Found the Universe

by Marcia Bartusiak · 6 Apr 2009 · 412pp · 122,952 words

in the early sixteenth century. And so the hazy pair came to be named in honor of the Portuguese-born explorer. The Large and Small Magellanic Clouds are each a chaotic collection of stars, richly diffused with glowing gas. Such novel and fascinating sights were a compelling reason for European and American

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reveal a few surprises along the way. The Harvard survey was no exception, but it took many photographs to get there. The Small and Large Magellanic Clouds (top left, bottom left) as seen from Cerro-Tololo Inter-American Observatory, in Chile. The Milky Way is on the right. (Roger Smith/NOAO/AURA

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1904, though, did variable stars come back into her life in full force. Peering through a magnifying eyepiece at two photographic plates of the Small Magellanic Cloud, taken at different times, she noticed that several stars in the cloud had changed in brightness. On one plate a particular star was relatively luminous

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readily and meticulously updated her count, so much so that a Princeton astronomer described her as a “variable-star ‘fiend.’” Soon she included the Large Magellanic Cloud in her tally, and by 1907 she found a record-setting total of 1,777 new variable stars residing within the prominent, mistlike clouds (before

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that, only a couple of dozen variable stars had been detected in the Magellanic Clouds). She dutifully reported her findings in the 1908 Annals of the Astronomical Observatory of Harvard College, with thirteen pages taken up with listing every new

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and maximum brightness. More intriguing was what she wrote at the end of this paper. Over the course of her painstaking examination of the Small Magellanic Cloud, she came to notice a special group of variable stars, sixteen in number. They were later identified as Cepheid variables, stars that are thousands of

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. This historic finding was published as Harvard College Observatory Circular, No. 173, a three-page paper titled “Periods of 25 Variable Stars in the Small Magellanic Cloud” and now considered a “masterpiece” of scientific literature. Henrietta Leavitt's historic 1912 graph showing how a Cepheid's brightness increases as the variable star

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Shapley. Once he arrived at Harvard in 1920, she lost no time in asking his advice on advancing her research on the stars in the Magellanic Clouds. By then Shapley had already calibrated the Cepheids, but he told Leavitt he would like to see a deeper investigation of the short-period variables

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globular clusters and the size of the galactic system,” he said. Moreover, does the same period-luminosity law also work for stars in the Large Magellanic Cloud? he asked. He wished her success on tackling these questions. But just as she was on the verge of completing her prolonged stellar magnitude project

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person to try to confront the Cepheid distance problem was Ejnar Hertzsprung, who had initially recognized that Leavitt's twenty-five variables in the Small Magellanic Cloud were specifically Cepheid stars. He began to look at the Cepheids best studied within the Milky Way, thirteen in all. He couldn't measure their

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basic idea.) Hertzsprung's approach in the end provided a crude statistical calibration, one that he then applied to Leavitt's Cepheids in the Small Magellanic Cloud. He concluded that the cloud was 30,000 light-years distant, one of the greatest distances then measured for a celestial object. This demonstrated for

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concluded that they were giant stars, far bigger than our Sun. Inspired by Hertzsprung, Russell proceeded to make his own distance calculation to the Small Magellanic Cloud, arriving at 80,000 light-years. Both estimates were highly uncertain and turned out to be far less than current distance measurements (210,000 light

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, though, that Shapley parted company with Hertzsprung. He didn't use Leavitt's period-luminosity relationship, which was based solely on stars in the Small Magellanic Cloud, but instead constructed his own relationship based as well on the Cepheids in the Milky Way, in order to obtain an “improved and extended” period

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mightily to check with Leavitt on this question, writing several times to her boss, Edward Pickering, on whether she had detected fast variables in the Magellanic Clouds and found them to obey her rule. Pickering assured him that photographs were being taken. But progress on the question was occurring at a glacial

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, he called it a “normal spiral;” if elongated, a “barred spiral.” The nongalactic nebulae that didn't fit either class, like those resembling the chaotic Magellanic Clouds, were tagged “irregulars.” But the IAU committee dragged its feet on Hubble's naming system and desired some changes, a rebuke that may have had

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discovered in 1884 by his former Yerkes colleague E. E. Barnard. The nebula stood out from the pack because it looked strikingly similar to the Magellanic Clouds in the southern celestial hemisphere. The 100-inch and 60-inch telescopes (left, right) side by side on Mount Wilson (Courtesy of the Archives, California

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faint nebulae,” responded Shapley. “As for N.G.C. 6822, I think there is no doubt but that it is another star cloud like the Magellanic Cloud.” Although there was no love lost between Shapley and Hubble, the two astronomers maintained a courteous correspondence, perhaps adhering to that old adage, “Keep your

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proceeded to estimate the distance of NGC 6822 by comparing its size and the observed magnitudes of its brightest stars to that of the Large Magellanic Cloud. Interestingly, he arrived at a distance of about a million light-years. “It appears to be a great star cloud that is at least three

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he was seeing two additional novae and wrote “N” beside each one on his plate to mark their location. From his earlier work on the Magellanic cloud–like NGC 6822, Hubble knew that he had to make sure his newly spied objects were truly novae and not some other phenomenon. For a

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Mount Wilson (Courtesy of AIP Emilio Segrè Visual Archives) • • • By 1929 Hubble had determined the distances to twenty-four galaxies (including the Small and Large Magellanic Clouds), the most remote then judged to reside some 6 million light-years away. He accomplished this feat by establishing a ladder of measurements, one rung

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” for stars silently disappeared from the astronomical literature. 6. It Is Worthy of Notice 90 Ancient Persians called the biggest one Al Bakr: The Large Magellanic Cloud was named Al Bakr by the noted Persian astronomer Al-Sûfi in his Book of Fixed Stars, written in 964. While not visible from northern

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a typed, unsigned note in which either Walter Adams or George Hale remarks that by an “ingenious argument” Hertzsprung has found the distance of the Magellanic Cloud “to be 10,000 parsecs—the greatest distance we have yet had occasion to mention.” But the published error may have contributed to the delay

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on this question: Shapley was still concerned late in his project. “I notice that a great many of the hundreds of [variables in the Small Magellanic Cloud] are fainter. Does Miss Leavitt know if they have shorter periods[?] … The matter is of much importance, as you know, because of the relation between

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Pacific. Lankford, J. 1997. American Astronomy: Community, Careers, and Power, 1859-1940. Chicago: University of Chicago Press. Leavitt, H. S. 1908. “1777 Variables in the Magellanic Clouds.” Annals of the Astronomical Observatory of Harvard College 60: 87-108. Leavitt, H., and E. C. Pickering. 1912. “Periods of 25 Variable Stars in the

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Small Magellanic Cloud.” Harvard College Observatory Circular no. 173: 1-3. Lemaître, G. 1931a. “A Homogeneous Universe of Constant Mass and Increasing Radius Accounting for the Radial Velocity

Extraterrestrial Civilizations

by Isaac Asimov · 2 Jan 1979 · 330pp · 99,226 words

. They were first described in 1521 by the chronicler accompanying Magellan’s voyage of circumnavigation of the globe—so they are called the Large Magellanic Cloud and the Small Magellanic Cloud. They were not studied in detail until John Herschel observed them from the astronomic observatory at the Cape of Good Hope in 1834

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(the expedition that fueled the Moon Hoax). Like the Milky Way, the Magellanic Clouds turned out to be assemblages of vast numbers of very dim stars, dim because of their distance. In the first decade of the twentieth century

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, the American astronomer Henrietta Swan Leavitt (1868–1921) studied certain variable stars in the Magellanic Clouds. By 1912, the use of these variable stars (called Cepheid variables because the first to be discovered was in the constellation Cepheus) made it possible

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to measure vast distances that could not be estimated in other ways. The Large Magellanic Cloud turned out to be 170,000 light-years away and the Small Magellanic Cloud 200,000 light-years away. Both are well outside the Galaxy. Each is a galaxy in its own right

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. They are not large, however. The Large Magellanic Cloud may include perhaps 10 billion stars and the Small Magellanic Cloud only about 2 billion. Our Galaxy (which we may refer to as the Milky Way Galaxy if we wish to distinguish

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it from others) is 25 times as large as both Magellanic Clouds put together. We might consider the Magellanic Clouds as satellite galaxies of the Milky Way Galaxy. Is this all, then? A certain suspicion arose concerning a faint, fuzzy patch of

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exactly like starlight. Another alternative, then, was that the Andromeda Nebula was a conglomeration of stars, but one that was even more distant than the Magellanic Clouds, so that the individual stars could not be made out. When Thomas Wright had first suggested in 1750 that the visible stars were collected into

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methods of distance determination, it would appear that the Andromeda Galaxy is 2,200,000 light-years distant, eleven times as far away as the Magellanic Clouds. No wonder it was difficult to make out the individual stars. The Andromeda Galaxy is no dwarf, however. It is perhaps twice as large as

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the Milky Way Galaxy and may contain up to 600 billion stars. The Milky Way Galaxy, the Andromeda Galaxy, and the two Magellanic Clouds are bound together gravitationally. They form a “galactic cluster” called the Local Group and are not the only members, either. There are some twenty members

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roughly that there are on the average 10 billion stars to a galaxy, so that the average galaxy is of the size of the Large Magellanic Cloud. That would mean that in the observable universe, there are as many as 1,000,000,000,000,000,000,000 (a billion trillion) stars

Big Bang

by Simon Singh · 1 Jan 2004 · 492pp · 149,259 words

led her to a rather cunning and brilliant idea. She made her breakthrough by focusing her attention on the stellar formation known as the Small Magellanic Cloud, named after the sixteenth-century explorer Ferdinand Magellan, who recorded it when he sailed the southern oceans while circumnavigating the globe. Because the Small

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Magellanic Cloud is visible only from the southern hemisphere, Leavitt had to rely on photographs taken at Harvard’s southern station at Arequipa in Peru. Leavitt managed

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to identify twenty-five Cepheid variables within the Small Magellanic Cloud. She did not know the distance from the Earth to the Small Magellanic Cloud, but she suspected that it was relatively far away and that the Cepheids within it were relatively close together

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Cepheids were more or less at the same distance from the Earth. Suddenly, Leavitt had exactly what she needed. If the Cepheids in the Small Magellanic Cloud were all roughly the same distance away, then if one Cepheid was brighter than another it was because it was intrinsically more luminous, not just

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apparently brighter. The assumption that the stars in the Small Magellanic Cloud were roughly equidistant from the Earth was something of a leap of faith, but a very reasonable one. Leavitt’s line of thinking was akin

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now ready to explore the brightness versus period relationship for Cepheids. Building on the assumption that the apparent brightness of each Cepheid in the Small Magellanic Cloud was a true indication of its actual brightness in relation to the other Cepheids in the Cloud, Leavitt plotted a graph of the apparent brightness

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. This was a staggering result, pregnant with cosmic repercussions, but it was published with the understated title ‘Periods of 25 Variable Stars in the Small Magellanic Cloud’. The power of Leavitt’s discovery was that it was now possible to compare any two Cepheids in the sky and work out their relative

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be 12 times as distant, because 122 = 144. Figure 45 These two graphs show Henrietta Leavitt’s observations of Cepheid variable stars in the Small Magellanic Cloud. Graph (a) is a plot of brightness (on the vertical axis) against period, measured in days (on the horizontal axis), and each point represents a

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vast majority of other galaxies are even farther away. The only exceptions to this are a small number of dwarf galaxies, such as the Small Magellanic Cloud studied by Henrietta Leavitt. This is now known to be a small, satellite galaxy gravitationally attached to and on the periphery of our Milky Way

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, Ludwig 136 singularity 489 Sirius 172-3,174,239,244 Sizi, Francesco 67 Skellet, Melvin 405 Slipher,Vesto 247-9,250,251-2,256 Small Magellanic Cloud 209-10, 211, 226 Smith, Barnabas 117 Smithsonian National Air and Space Museum 437, 439 Smoot, George 450-4, 456,459-62 Sochocky, Sabin von

Neutrino Hunters: The Thrilling Chase for a Ghostly Particle to Unlock the Secrets of the Universe

by Ray Jayawardhana · 10 Dec 2013 · 203pp · 63,257 words

possible. Neutrinos were the first harbingers of the dramatic demise of a massive, bloated star that exploded 160,000 light-years away in the Large Magellanic Cloud, a satellite galaxy of the Milky Way that appears as a fuzzy patch in the southern sky. Three underground detectors in Japan, Russia, and the

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absolutely stunning at night when the star-studded Milky Way arches across the sky, accompanied by two fuzzy patches of light, the Large and Small Magellanic Clouds, off to one side. Ian Shelton, a thirty-year-old Canadian who grew up in Winnipeg, happened to be here at Las Campanas on the

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by eye. As he often did, that night Shelton trained the little telescope on the bigger of the Milky Way’s two sidekicks, the Large Magellanic Cloud (LMC), and registered long exposures of this dwarf galaxy onto old-fashioned photographic plates in order to look for variable stars in its midst. In

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the precursor star’s gravitational binding energy goes into neutrinos of all flavors, while barely half a percent appears as visible light. Since the Large Magellanic Cloud is located some 160,000 light-years away, the neutrinos generated in the supernova that reached the Earth in 1987 began their journey 160,000

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of matter could enhance neutrino oscillations. 1987: Kamiokande and two other experiments recorded a total of two dozen neutrinos from Supernova 1987A in the Large Magellanic Cloud, a satellite galaxy of the Milky Way located 160,000 light-years away. These were the first neutrinos to be detected from beyond the solar

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the weak force. light-year: The distance that light travels in a year, just under 10 trillion kilometers (or about 6 trillion miles). Magellanic Clouds: The Large and Small Magellanic Clouds (LMC and SMC) are two irregularly shaped satellite galaxies of the Milky Way. Supernova 1987A occurred in the LMC. Manhattan Project: The research

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that accumulates material from a companion. Elements heavier than iron (e.g., gold) are produced only in supernovae. Supernova 1987A: The supernova in the Large Magellanic Cloud seen in the year 1987. Detectors on Earth also recorded neutrinos emitted during this supernova explosion. theory: A hypothesis that has withstood experimental and/or

A Grand and Bold Thing: An Extraordinary New Map of the Universe Ushering

by Ann K. Finkbeiner · 16 Aug 2010 · 225pp · 65,922 words

call it the Milky Way. The Milky Way is bound by gravity—along with around thirty-five galaxies, including Andromeda and the Large and Small Magellanic clouds—in a cluster; ours is called the Local Group. The Local Group is one of around one hundred galaxy clusters gathered by gravity but not

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, 35, 39, 45, 55, 77, 104, 156, 177–78, 180 becomes survey director, 138 redshift survey idea of, 32–33 Lamb, Don, 36–37 Large Magellanic cloud, 31 Large Synoptic Survey Telescope (LSST), 179, 197 Lawrence Berkeley National Laboratory, 180 Legacy project, 177 Leger, French, 84, 112, 117, 124 cracked mirror problem

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mirror, problems of, 52–54 software problem of, 117 thermal disappearance of, 110 tracking problem of, 116–17, 119 ubercal code and, 143–44 Small Magellanic cloud, 31 small redshift survey (SRS), 74 Smee, Steve, 49, 88, 121–22 Snedden, Stephanie, 112 software crisis, 61–71, 76, 105 astrometric pipeline and, 62

What We Cannot Know: Explorations at the Edge of Knowledge

by Marcus Du Sautoy · 18 May 2016

know if there was any pattern to the pulse of these stars, Leavitt focussed on a batch of stars that were located in the Small Magellanic Cloud and were therefore believed to be at similar distances from the Earth. When she plotted luminosity against the period of pulsation, she discovered a very

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, 248, 278–82, 283, 284, 289, 290, 293, 294 61 Cygni 201, 202 sleep, consciousness and 315–16, 339–41, 342, 343, 344, 346 Small Magellanic Cloud 203 Socrates 412 space-time: black holes and 276–8, 283, 284, 285; God and 296–8; origin of concept 262–4; shape of 264

QI: The Book of General Ignorance - The Noticeably Stouter Edition

by Lloyd, John and Mitchinson, John · 7 Oct 2010 · 624pp · 104,923 words

). In the Northern Hemisphere, you can see the Milky Way and Andromeda (M31), while in the Southern Hemisphere you can see the Large and Small Magellanic Clouds. Some people with exceptional eyesight claim to be able to see three more: M33 in Triangulum, M81 in Ursa Major and M83 in Hydra, but

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1 Laika (dog) 1 lakes, largest in Canada 1 Landseer, Edwin 1 Landy, John 1 Lapland 1, 2, 3 Laprise, Larry 1 Large and Small Magellanic Clouds 1 lateral line 1, 2 Lawrence, D. H. 1, 2 Le Carré, John 1 Leasor, James 1 Leeuwenhoek, Antonie van 1 lemmings, death of 1