Edward Charles Pickering(1846 — 1919)
Edward Charles Pickering
États-Unis
8 min read
American astronomer (1846–1919), director of the Harvard Observatory for 42 years. He revolutionized stellar classification and led the famous group known as the "Harvard Computers," composed mostly of women scientists.
Frequently asked questions
Key Facts
- 1846: born in Boston, Massachusetts
- 1876: becomes director of the Harvard College Observatory, a post he holds until his death
- 1884: introduces standardized stellar photometry with the Harvard magnitude scale
- 1890–1924: publication of the Henry Draper Catalogue, classifying more than 225,000 stars by spectrum
- 1919: dies, leaving behind a team of women computers (including Annie Jump Cannon) who transformed astronomy
Works & Achievements
The first major photometric catalogue published by Pickering, providing precise brightness measurements for 4,260 stars. It established the standards for stellar magnitude measurement for a generation of astronomers.
A catalogue of the spectra of 10,351 stars photographed and classified at the Harvard Observatory. It laid the groundwork for the spectral classification system that would become universal.
An expanded and corrected version of the 1884 photometric catalogue, now covering more than 9,000 stars. It remained the international reference for stellar magnitudes for several decades.
The masterwork of the Harvard Observatory under Pickering, cataloguing the spectra of more than 225,000 stars classified by Annie Jump Cannon. It stands as one of the most ambitious achievements in observational astronomy of the 20th century.
An international network for observing stars whose brightness varies over time, initiated and coordinated by Pickering. This pioneering collaborative programme led to major discoveries, including Leavitt's law on Cepheid variables.
A classification of stars by surface temperature, developed under Pickering's direction by Annie Jump Cannon. Adopted internationally in 1922, this system is still taught and used worldwide.
Anecdotes
One day in 1881, exasperated by the repeated mistakes of his male assistants, Edward Pickering remarked sarcastically that his Scottish maid, Williamina Fleming, could do a better job than they could. He made good on the quip: he hired her at the Observatory. Fleming became one of the most productive astronomers in history, single-handedly cataloging more than 10,000 stars.
Pickering gradually assembled a team of women computers known as the “Harvard Computers.” Paid around 25 cents an hour — less than their male counterparts — they produced first-rate scientific work. Among them, Annie Jump Cannon classified more than 350,000 stars, and Henrietta Swan Leavitt discovered the period-luminosity relationship of Cepheid stars, the cornerstone of measuring distances across the Universe.
Pickering was a pioneer of large-scale astronomical photography. He equipped Harvard Observatory with an observation station in Peru to cover the southern hemisphere, creating the first truly global star catalog. Thousands of photographic plates were taken, forming a unique archive that still allows researchers today to study how the sky has changed over more than a century.
After the death of astronomer Henry Draper in 1882, his widow Anna Palmer Draper generously funded Harvard Observatory to carry on his work. Thanks to her patronage, Pickering was able to launch the Henry Draper Catalogue, a monumental record of the spectra of more than 225,000 stars, published between 1918 and 1924, which remained the world standard for decades.
Pickering was convinced that modern astronomy could only move forward by collecting large amounts of standardized data. As early as the 1880s, he established a network of amateur correspondents around the world to observe variable stars simultaneously. This collaborative approach, ahead of its time, foreshadowed the large-scale citizen science projects of the 21st century.
Primary Sources
A Catalogue of 4260 Stars, observed with the Meridian Photometer during the years 1879-1882. The observations were made with the greatest care, and the results are believed to be the most accurate stellar magnitudes yet determined.
The spectra of 10,351 stars have been examined and the classification of each recorded. The work was carried out at the Harvard College Observatory under the direction of the Director, Professor Edward C. Pickering.
The importance of a southern station for the purpose of completing the photographic survey of the entire sky cannot be overestimated. Without it, our catalogue must remain forever incomplete and our understanding of the stellar universe partial.
The work of the women employed in the reduction of the photographs continues to advance satisfactorily. Miss Cannon has during the past year classified the spectra of more than 5,000 stars, bringing the total of her classifications to over 150,000.
Key Places
Birthplace of Edward Pickering, born on July 19, 1846. Boston was at the time a major American intellectual center, home to Harvard University and MIT.
The site of Pickering's entire astronomical career, which he directed from 1877 to 1919. It was here that he assembled the team of Harvard Computers and built the largest stellar catalog of his era.
The institution where Pickering taught physics from 1867 to 1877 and founded the first practical physics laboratory in the United States, before moving to Harvard.
An observing station founded by Pickering in 1891 at an altitude of 2,400 meters to photograph the southern sky. It made it possible to complete the universal stellar catalog and discover previously unknown stars.
Home to the major American scientific institutions with which Pickering collaborated throughout his career, most notably the National Academy of Sciences, of which he was a prominent member.
