Harvard Computers: women astronomers 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

they won the right to vote, several of them made contributions of such significance that their names gained honored places in the history of astronomy: Williamina Fleming, Antonia Maury, Henrietta Swan Leavitt, Annie Jump Cannon, and Cecilia Payne. This book is their story. PART ONE The Colors of Starlight I swept around for comets about an hour, and then

…

the observatory at Wellesley College. Qualified Radcliffe astronomy students occasionally landed unpaid assistantships at the Harvard Observatory. In 1895 Searle and Pickering selected Henrietta Swan Leavitt for this honor, and Annie Jump Cannon a short while later. These two ladies displayed maturity well beyond that of the typical matriculant. They had both completed college studies, traveled

…

Kiss Me! It was almost as if the distant stars had really acquired speech, and were able to tell of their constitution and physical condition. —Annie Jump Cannon (1863–1941) Curator of Astronomical Photographs, Harvard College Observatory The fact that I was a girl never damaged my ambitions to be a pope or

…

train. It went to all fifteen committee members and about as many nonmembers selected for their strong interest or expertise in classification—notably Annie Cannon, Williamina Fleming, Antonia Maury, and Ejnar Hertzsprung, the Danish astronomer who had so emphatically endorsed Miss Maury’s approach. The questionnaire began with a recapitulation of the committee’s

…

She frequently consulted the director of the Harvard College Observatory for advice, and asked him to recommend guest lecturers. For several years beginning in 1906, Annie Jump Cannon made a summer pilgrimage to Nantucket in this capacity. She also taught a correspondence course in astronomy and helped bring Ida Whiteside of the Wellesley

…

human mind could traverse space and time. • • • CECILIA PAYNE PATIENTLY SIFTED the same objective-prism plates that had passed through the hands of Nettie Farrar, Williamina Fleming, Antonia Maury, and Annie Cannon. In the runic line patterns, which had helped her predecessors sort the stars into categories, Miss Payne read a new subtext. It

…

of her fellow scientists looked down on her on account of her sex. She faced scant risk of that at the Harvard Observatory, where Annie Jump Cannon could bake a batch of oatmeal cookies for a meeting of the Bond Astronomical Club and then lecture authoritatively to the assembled about her latest

…

The committee concurred. Shapley, in his glee, prepared a private citation in advance of the official one yet to come. His read as follows: Dr. Annie Jump Cannon the benign presence of the Brick Building, noted collector of degrees and medals, author of nine immortal volumes and several thousand oatmeal cookies, Virginia Reeler

…

of $1,000 to two worthy recipients, Dr. Helen Dean King, a biologist at the Wistar Institute of the University of Pennsylvania, and Dr. Annie Jump Cannon of the Harvard College Observatory. With that decision, the twelve members declared themselves satisfied with the progress they had seen, and they drafted a resolution

…

demands a justification in the highest service which it is possible for one to give.” Miss Cannon earmarked her $1,000 bounty to endow the Annie Jump Cannon Prize. She wished it to be awarded biennially or triennially by the American Astronomical Society, to a deserving woman of any nationality. It would

…

’s first sight of Miss Payne surprised him, he later wrote, because he had expected her to be as old as the famed Harvard astronomer Annie Jump Cannon. Her youth and bearing put him in mind of “a ripe peach left alone on a tree, darkened, wrinkled a little outside, but the

…

she knew, could produce a whole greater than the sum of its components. Single or married, Cecilia was still her top pick for the first Annie Jump Cannon Prize, to be awarded at the December 1934 meeting of the American Astronomical Society (AAS), in Philadelphia. It just so happened that the current president

…

house in Lexington on a large lot, where they cleared the yard of rocks and brambles to make room for flowers and trees. • • • THE ANNIE JUMP CANNON PRIZE, awarded every three years by the executive council of the American Astronomical Society, increased gradually in cash value over time. In 1937 it went

…

died young. “During the past year,” Shapley rued in his 1941 annual report, “the observatory suffered a heavy loss through the death of Miss Annie Jump Cannon. In her seventy-seventh year Miss Cannon was still engaged in classifying the spectra of the stars, work in which she was a pioneer and

…

THE 1943 WINTER MEETING of the American Astronomical Society, held in Cincinnati, the executive council moved to award the fourth Annie Jump Cannon Prize to Miss Cannon’s old friend and coworker Antonia Maury. The seventy-seven-year-old Miss Maury, a party to the discovery of spectroscopic binaries in 1889, had nurtured her

…

distribution. The days of the human computer were numbered—by zeros and ones. • • • FORMER PICKERING FELLOW Helen Sawyer Hogg took the news of her Annie Jump Cannon Prize not exactly in stride. Pleasure jostled with anxiety and the lethargy that had come over her in the past few months. “All Spring I

…

asked Frank to get me an indefinite leave of absence from my university position here, but he is very much upset at the thought.” The Annie Jump Cannon Prize seemed to add a new weight of obligation. “In my opinion, this award carries with it a certain amount of responsibility, when made

…

synonymous with photometry and photography, Shapley tied it securely to graduate education. He had fostered a generation of Harvard astronomers. Mrs. Hogg accepted her Annie Jump Cannon Prize at the June 1950 meeting of the AAS, held at the University of Indiana in Bloomington. Not long afterward, on New Year’s Day

…

P. Haynes of Cornell University, who shared the 1989 honor with Riccardo Giovanelli for their joint mapping of the large-scale distribution of galaxies. The Annie Jump Cannon Prize likewise endures. It was awarded to Miss Cannon’s former recorder, Margaret Walton Mayall, in 1958, and to Nantucket observatory director Margaret Harwood

…

of the staff is female. • • • THE MONUMENTAL WORK of stellar classification known as the Henry Draper Catalogue and Extension, begun under Williamina Fleming in the 1880s and continued through 1940 by Annie Jump Cannon, is still in regular use. Every astronomy student learns the temperature order of the stars by memorizing Oh, Be A Fine

…

El Misti. The observer’s house built by William Pickering is at right. Annie Jump Cannon, a Wellesley College graduate, was continuing her astronomy studies at Radcliffe and also assisting at the Harvard Observatory when this photograph was taken, ca. 1895. Antonia Maury (far right) and her sister Carlotta (far left) are pictured here with

…

as 47 Tucanae. Called a fly spanker for its resemblance to a fly swatter, this diminutive instrument helped computers compare the relative brightness of stars. Henrietta Swan Leavitt discovered a relation between certain stars’ peak brightness and the time it took them to cycle through their changes in magnitude. This “period-luminosity

…

Star in Norma,” in the pages of Astronomy and Astro-Physics. Pickering’s correspondence with Antonia Maury, also with the Reverend Mytton Maury, is held in the Harvard University Archives. CHAPTER FIVE: Bailey’s Pictures from Peru Annie Jump Cannon was a lifelong diarist and prolific letter writer. Her diaries, scrapbooks, and other papers,

…

including the libretti she collected for the many opera performances she attended, are held in the Harvard University Archives. Antonia Maury’s “Verses to the Vassar Dome,” written in

…

Rugged Ways to the Stars, published in 1969. He dedicated the book “To the memory of Henry Norris Russell.” Margaret Harwood’s letters to Annie Jump Cannon, Edward Pickering, and Harlow Shapley are preserved in the Harvard University Archives along with other materials pertaining to the observatory, but most of her private

…

in America, at the Radcliffe Institute for Advanced Study, Cambridge. CHAPTER ELEVEN: Shapley’s “Kilo-Girl” Hours As chairman of the Astronomical Fellowship Committee, Annie Jump Cannon chronicled the activities of current and past Pickering Fellows in her write-ups for the Nantucket Maria Mitchell Association Annual Report. These can be read

…

construction of a 24-inch astrophotographic telescope Edward Pickering discovers the first spectroscopic binary; Antonia Maury finds the second one. 1890 “The Draper Catalogue of Stellar Spectra” is published in the Annals, vol. 27, with classifications made by Williamina Fleming. Solon Bailey establishes Harvard’s Boyden Station at Arequipa. 1891 William Pickering takes over

…

the observatory, beginning with Williamina Fleming’s discovery of Nova Carinae (her second nova) from photographs taken at Arequipa; her third such discovery, Nova Centaurus, follows a few months later. Henrietta Swan Leavitt volunteers at the observatory Solon Bailey discovers many variables within certain star clusters of the Southern Hemisphere. 1896 Annie Jump Cannon joins the observatory as

…

a research assistant, commences her study of the spectra of bright southern stars. Bruce telescope arrives at Arequipa. 1897 Antonia Maury publishes “The Spectra 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 photographic magnitudes. Williamina Fleming elected to honorary membership in the Royal Astronomical Society. 1907 Annie Cannon publishes her “Second Catalogue of Variable Stars” in

…

Williamina Fleming publishes “A Photographic Study of Variable Stars” in the Annals, vol. 47 Margaret Harwood joins the staff. 1908 Edward Pickering publishes the Revised Harvard Photometry in the Annals, vols. 50 and 54. Solon Bailey compiles a whole-sky catalogue of 263 bright clusters and nebulae in the Annals, vol. 60 Henrietta Leavitt

…

by Annie Cannon. 1911 Williamina Fleming dies. American Association of Variable Star Observers is founded by William Tyler Olcott, one of Pickering’s volunteer contributors. 1912 Harvard Bulletin switches from handwritten and mimeographed production to printed format. Edward Pickering and Annie Cannon demonstrate the brightness of B stars Henrietta Leavitt publishes her “period-luminosity

…

of the universe. 1921 Harlow Shapley is named fifth director. Henrietta Leavitt dies Harlow Shapley and Annie Cannon explore the relation between spectral type and magnitude. 1922 International Astronomical Union adopts Harvard’s Draper stellar classification, representing the work of Williamina Fleming, Antonia Maury, and especially Annie Jump Cannon. 1923 Adelaide Ames enrolls as Harvard’s first graduate student

…

dies. International Astronomical Union meets at Harvard. 1933 Antonia Maury publishes “The Spectral Changes of Beta Lyrae” in the Annals, vol. 84. Several Harvard telescopes move to rural site at Oak Ridge. 1934 Cecilia Payne and Sergei Gaposchkin elope. Cecilia Payne-Gaposchkin wins the Annie Jump Cannon Prize. 1935 Harlow Shapley inaugurates graduate summer program

…

in astronomy and astrophysics. 1939 Annie Cannon finds Harvard’s ten thousandth variable star. 1941 Annie Cannon dies. 1943 Antonia Maury receives the Annie Jump Cannon Prize. 1946 An Observatory Council, including Bart Bok, Donald Menzel, and Cecilia Payne-Gaposchkin, is appointed to advise the director on policies and

…

completes the Henry Draper Extension, published as the Annie J. Cannon Memorial Volume in the Annals, vol. 112. 1950 Helen Sawyer Hogg wins the Annie Jump Cannon Prize. 1952 Antonia Maury dies. Harlow Shapley retires Donald Menzel becomes acting director. 1954 Donald Menzel officially named sixth director of the observatory. 1955 Smithsonian Astrophysical Observatory moves

…

of variable stars and taught others the techniques. For many years he collected, collated, and published reports for the American Association of Variable Star Observers. Annie Jump Cannon (December 11, 1863–April 13, 1941) classified the spectra of several hundred thousand stars for the nine-volume Henry Draper Catalogue and its Extension.

…

12, 1927) learned from Edward Pickering how to set up a practical physics laboratory, and established one at Wellesley College, where she taught and inspired Annie Jump Cannon. Harvia Hastings Wilson (December 23, 1900–May 4, 1989), a 1923 Vassar alumna, delayed the start of her graduate studies till 1924 because of

…

carries stellar distance measurements only so far—no more than a few hundred light-years from the Sun. CHAPTER NINE: Miss Leavitt’s Relationship As Annie Jump Cannon, Antonia Maury, Henry Norris Russell, and others suspected, the various color categories in the Draper classification are indeed associated with specific stages in the lives of stars

…

College, 14, 20, 37, 38, 42, 60, 61, 79, 80, 101–2, 111, 128, 144, 145, 150, 162, 171–72, 181, 212, 251, 273 Annie Jump Cannon Memorial Volume, 247–48, 253, 279 time line of published papers, 273–79 See also Draper Catalogue; Draper Extension; Harvard College Observatory publications; other specific

…

papers Annie Jump Cannon Prize. See Cannon Prize ants and ant research, 169–70, 196, 236, 237 Arequipa observatory. See Boyden Station (Arequipa, Peru) Argelander, Friedrich Wilhelm, 109,

…

, 198–99, 200–201, 213–14 Campbell, Leon, 110, 148, 149, 171, 286 Cannon, Annie Jump, 87, 286 as AAS treasurer, 156, 277 and Annie Jump Cannon Prize, 235–36, 242, 246 arrival at Harvard, 72, 74–75, 275 background and studies, 71, 72, 74, 90, 91 death of, 247, 279 honors

…

108, 139, 143, 296 stellar temperature and, 206–8, 212 See also Cannon, Annie Jump; Fleming, Williamina; Maury, Antonia Draper Extension, 213, 243, 279, 297 Annie Jump Cannon Memorial Volume, 247–48, 253, 279 Draper Medal, 18, 230–31, 260, 278 Draper Memorial project: establishment of, 19–20 funding and finances, 20, 21

Big Bang

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

do a better job. To prove his point, he sacked his allmale team, hired women computers to replace them and put his maid in charge.Williamina Fleming had been a teacher in Scotland before emigrating to America, where she had been abandoned by her husband when pregnant, forcing her to take a

…

past. Figure 43 The Harvard ‘computers’ at work, busy examining photographic plates while Edward Pickering and Williamina Fleming watch over them. On the back wall are two plots that show the oscillating brightness of stars. Although Williamina Fleming’s team of women computers were supposed to focus on the drudgery of harvesting data from

…

conclusions. Endless days spent staring at the photographic plates had given them an intimate familiarity with the stellar objects that they were surveying. For example, Annie Jump Cannon catalogued roughly 5,000 stars per month between 1911 and 1915, calculating the location, brightness and colour of each one. She drew upon her hands

…

sense of sight, thus allowing them to pick up fine details that had been missed by others. The most famous member of Pickering’s team, Henrietta Leavitt, was also profoundly deaf. It was Leavitt who spotted features in the photographic plates that would settle the Great Debate once and for all. She

…

be a dim star that was close by, while an apparently dim Cepheid might actually be a bright star that was far away. Figure 44 Henrietta Leavitt, who rose from being an unpaid volunteer at Harvard College Observatory to make one of the most important breakthroughs in twentieth-century astronomy Astronomers had

…

fainter than another with a very similar period, then it must 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

…

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 galaxy. The term ‘nebula

…

years studying a particular type of star known as an RR Lyrae star, a type of variable star similar to a Cepheid variable star. Williamina Fleming, who worked alongside Henrietta Leavitt at the Harvard Observatory, had shown that the variability of RR Lyrae stars could be used, like Cepheids, to measure distances. So far

…

3, the original measurement to the Andromeda Galaxy had been performed using Cepheid variable stars, which had become the basic yardstick for measuring intergalactic distances. Henrietta Leavitt had shown that Cepheids have the useful property that the time period between two peaks in brightness is an excellent indication of their inherent luminosity

…

somewhat dry) account of the research projects pursued at the Harvard College Observatory from its founding until the mid-1920s. It covers the work of Henrietta Leavitt and Annie Jump Canon, and explains the techniques and instruments they employed. Harry G. Lang, Silence of the Spheres (Greenwood Press, 1994) Subtitled The Deaf

…

Experience in the History of Science, this book includes sections on John Goodricke and Henrietta Leavitt. Edwin Powell Hubble, The Realm of the Nebulae (Yale University Press, 1982) A somewhat technical book, based on the 1935 Silliman Lectures delivered by Hubble

…

, and Alison Doane at Harvard College Observatory, who changed her plans at short notice to show me the photographic stacks that house the work of Henrietta Leavitt and her colleagues. I have also been able to include several remarkable photographs of Fred Hoyle in this book, and I am enormously grateful to

Day We Found the Universe

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

receive much larger salaries. Three or four times as many assistants can thus be employed, and the work done correspondingly increased for a given expenditure.” Williamina Fleming (standing) directs her “computers” while Harvard Observatory director Edward Pickering looks on (Harvard College Observatory) These women “computers,” as they were called, many with college

…

, and cheaply—numbered each star on a given plate, determined the star's exact position, and assigned it either a spectral class or photographic magnitude. Annie Jump Cannon, who established the stellar classification system adopted internationally in the course of this work, praised Pickering's modern outlook. “He treated [the computers] as equals

…

of courtesy as if he were meeting them at a social gathering.” He was their gallant Victorian gentleman. Pickering's first hire was his housekeeper, Williamina Fleming, who had displayed a keen intelligence in carrying out her duties. Frustrated one day by a male assistant's ineptitude, Pickering had declared that his

…

in 1919, some forty women came to be employed in “Pickering's harem,” as it was jokingly known. One of his most brilliant choices was Henrietta Leavitt, who first began work at the Harvard Observatory as a volunteer. Leavitt grew up in Massachusetts, within a big and supportive family (she was the

…

and white images of a star did not exactly match, the star was likely changing its intensity and so was suspected to be a variable. Henrietta Leavitt at her Harvard College Observatory desk (AIP Emilio Segrè Visual Archives) After writing up a draft of her initial research, Leavitt left Harvard in 1896

…

, 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's period gets longer (From Harvard College Observatory Circular, No

…

on the verge of completing her prolonged stellar magnitude project—possibly when she would have at last gone back to her work on the Cepheids—Henrietta Leavitt passed away at the age of fifty-three. She had faced a long and grueling struggle with stomach cancer. By the time of her death

…

to identify Cepheids which he knew would serve as his measuring tape out to the globular clusters. He was quite aware of the paper that Henrietta Leavitt had published just a couple of years earlier and intended to apply it. “Her discovery … is destined to be one of the most significant results

…

supportive family: Johnson (2005), pp. 25–26. Many of the personal details of Leavitt's life are drawn from George Johnson's excellent biography of Henrietta Leavitt, the most comprehensive review of her life to date. 93 “For light amusements, she appeared to care little”: Bailey (1922), p. 197. 94 “For this

…

found enough Cepheids in Omega Centauri, the largest globular cluster in the Milky Way, to have discerned a crude period-luminosity relation six years before Henrietta Leavitt's first suggestion of such a rule. But Bailey was more focused on gathering data than interpreting it and so never made the connection. See

…

): 97-102. Bailey, S. I. 1919. “Variable Stars in the Cluster Messier 15.” Annals of the Astronomical Observatory of Harvard College 78: 248-50. ——. 1922. “Henrietta Swan Leavitt.” Popular Astronomy 30 (April): 197-99. Ball, R. S. 1895. The Great Astronomers. London: Isbister. Barnard, E. E. 1891. “Observations of the Planet Jupiter and

Coming of Age in the Milky Way

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

dimmer star is twice as far away. The relationship between the periodicity and the absolute magnitude of Cepheid variable stars was discovered in 1912 by Henrietta Swan Leavitt, one of a number of women hired at meager wages to work as “computers” in the Harvard College Observatory office in Cambridge, Massachusetts. Leavitt spent

…

appear farther away than they really 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

…

light on Hubble’s photographic plate really were stars, however, was open to contention; Shapley dismissed them as curds in a Laplacian nebula. Here, again, Henrietta Leavitt’s Cepheid variable stars provided the needed mileposts. Cepheids are bright enough to be discernible across intergalactic distances. Using the new one-hundred-inch telescope

…

of “computers”—spinsters, most of them, employed as staff members at a university where their sex barred them from attending classes or earning a degree. (Henrietta Leavitt, the pioneer researcher of the Cepheid variable stars that were to prove so useful to Shapley and Hubble, was a Harvard computer.) The computers were

…

of stars cataloged; Antonia Maury, Draper’s niece, reckoned that she had indexed the spectra of over five hundred thousand stars. Theirs was authentically Baconian work, of the sort Newton and Darwin claimed to practice but seldom did, and the ladies took pride in it; as the Harvard computer Annie Jump Cannon affirmed, “Every fact

…

galaxy. Time: 1911 Noteworthy Events: Ernest Rutherford determines that most of the mass of atoms is contained in their tiny nuclei. Time: 1912 Noteworthy Events: Henrietta Swan Leavitt discovers a correlation between the absolute magnitude and the period of variability of Cepheid variable stars, opening the door to their use as intergalactic distance

…

the absolute luminosity of stars from their spectra alone, making it possible to estimate the distances of millions of distant stars. Time: 1915 Noteworthy Events: Annie Jump Cannon classifies stars into categories according to their spectral type, a major step in discerning order underlying the diversity of the stars. Time: Arnold Sommerfeld refines

…

. Chamberlin, Science, Vol. 9, July 7, 1899, p. 12, in Albritton, 1980, p. 198. 2. Planck, Nobel Prize address, in Heathcote, 1954, p. 415. 3. Annie Jump Cannon, “Pioneering in the Classification of Stellar Spectra,” from “The Henry Draper Memorial,” Journal of the Royal Astronomical Society of Canada, Vol. 9, 1915, in Shapley

Broad Band: The Untold Story of the Women Who Made the Internet

by Claire L. Evans · 6 Mar 2018 · 371pp · 93,570 words

1880s, for example, the astronomer Edward Charles Pickering hired only women to analyze and classify stellar data for his Harvard lab, including his own maid, Williamina Fleming. Although he would later champion the women working in the observatory, even presenting papers on Fleming’s behalf at astronomical conferences, Pickering didn’t hire

…

nothing.” Known to history as “Pickering’s Harem,” the Harvard Computers cataloged ten thousand stars; Williamina Fleming, the erstwhile maid, discovered the Horsehead Nebula and helped develop a common designation system for stars, while her colleague Annie Jump Cannon could classify spectra at a rate of three stars a minute, and with a remarkable consistency

The Milky Way: An Autobiography of Our Galaxy

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

for someone to realize the period of a star’s variability was related to its brightness. In the early 1900s, a tragically underemployed woman named Henrietta Leavitt made that discovery while working as one of the so-called Harvard computers. Believe it or not, that was the more polite nickname given to

…

even the expansion of the universe. It’s safe to say that the course of human astronomy would have looked very different if not for Henrietta Leavitt, and yet no one thought to appropriately award her work until after she died. You fools. Cepheids aren’t the only stars your astronomers use

…

an opportunity to try to put yourselves at the center of everything? A young rebel named Harlow Shapley had been using Cepheid variables (thanks to Henrietta Leavitt) to map globular clusters in my halo. Globular clusters are just what your astronomers call collections of gas, dust, and up to thousands of stars

…

their classification—you know, the M-, G-, and O-type system. This scheme that I’ve deigned to use was developed by a human named Annie Jump Cannon. Cannon divided the stars she observed into seven different categories based on their surface temperature. From hottest to coolest (which also happens to be from

A Short History of Nearly Everything

by Bill Bryson · 5 May 2003 · 654pp · 204,260 words

benchmarks to measure the brightness (and hence relative distance) of other stars. Hubble's luck was to come along soon after an ingenious woman named Henrietta Swan Leavitt had figured out a way to do so. Leavitt worked at the Harvard College Observatory as a computer, as they were known. Computers spent their

…

it ensured that women ended up with an appreciation of the fine structure of the cosmos that often eluded their male counterparts. One Harvard computer, Annie Jump Cannon, used her repetitive acquaintance with the stars to devise a system of stellar classifications so practical that it is still in use today. Leavitt's

…

wealth of physical endowments, too.” Cropper, p. 423. 29 “At a single high school track meet . . .” Christianson, Edwin Hubble, p. 33. 30 “One Harvard computer, Annie Jump Cannon . . .” Ferris, Coming of Age in the Milky Way, p. 258. 31 “elderly stars that have moved past their ‘main sequence phase' . . .” Ferguson, Measuring the Universe

First Light: Switching on Stars at the Dawn of Time

by Emma Chapman · 23 Feb 2021 · 265pp · 79,944 words

, those with slightly less hydrogen B and so on down the alphabet, up to Q. This was rather cumbersome, and a later assistant of Pickering, Annie Jump Cannon, reorganised the system in 1901 in order of temperature, merging similar classes.5 She was quite the computer, classifying hundreds of stars per hour until

The Last Stargazers: The Enduring Story of Astronomy's Vanishing Explorers

by Emily Levesque · 3 Aug 2020

of the planet’s largest telescopes and flown over the Antarctic stratosphere in an experimental aircraft for her research. Her academic accolades include the 2014 Annie Jump Cannon Award, a 2017 Alfred P. Sloan fellowship, a 2019 Cottrell Scholar award, and the 2020 Newton Lacy Pierce Prize. She earned a bachelor’s degree

Extraterrestrial Civilizations

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

be assemblages of vast numbers of very dim stars, dim because of their distance. In the first decade of the twentieth century, 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