The Study of the Stars

by Edward Charles Pickering

Excerpt from The Study of the Stars The first accurate measures of the positions of the stars were made in the middle of the eighteenth century. The catalogue of Bradley in 1755 is even at the present time one of the best means of determining the early positions of the stars. A large number of Similar, but later, Observations by Hornsby are still unpublished. During the next hun dred years the meridian circle, which is at present the standard instru ment for determining the places of thegstars, was gradually evolved. In this instrument, a telescope is mounted so that it will point only to stars in the meridian, that is, to stars exactly north or south of the observer. The declinations of stars, corresponding to the latitude of points on the surface of the earth, are then measured by a finely gradu ated circle. Owing to the motion of the earth all stars cross the meridian twice during every twenty-four hours. The right ascension, corresponding to longitude, will be given by the time of transit. At first, this time was found by the eye and ear method in which the Observer counted the ticks of an accurate timepiece and compared them mentally with the instant at which the star appeared to cross a wire in the field of view of the telescope. About the middle of the nineteenth century a great advance was made by recording the time electrically on a chronograph. This method was known for many years as the Ameri can method, owing to its-introduction and general adoption in this country. This continued to be the standard method almost to the present time, and an enormous number of observations have been accumulated in this way, the total cost amounting to millions of dol lars. Perhaps the most valuable 'work of this kind is that of the Astronomische Gesellschaft, which, by international cooperation, secured accurate Observations of the positions of one hundred and sixty-six thousand stars. All stars of the ninth magnitude, and brighter, north of declination - 23° are included. Of the twenty zones, seven were Observed in Germany, four in the United States, three in Russia, one each in Algeria, Austria, England, Holland, Norway and Sweden. Of the American zones, one was observed at Albany, one at Washington. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works.

22 pages, Paperback

Published November 3, 2018

About the author

Edward Charles Pickering (July 19, 1846 – February 3, 1919) was an American astronomer and physicist as well as the older brother of William Henry Pickering.

Along with Carl Vogel, Pickering discovered the first spectroscopic binary stars. He wrote Elements of Physical Manipulations (2 vol., 1873–76).

Pickering attended Boston Latin School, and received his B.S. from Harvard in 1865. Soon after graduating from Harvard, Pickering taught physics at the Massachusetts Institute of Technology. Later, he served as director of Harvard College Observatory from 1877 to his death in 1919, where he made great leaps forward in the gathering of stellar spectra through the use of photography.

At Harvard, he recruited many women to work for him, including Annie Jump Cannon, Henrietta Swan Leavitt, and Antonia Maury. These women, who came to be known as "Pickering's Harem" by the scientific community, made several important discoveries at HCO. Leavitt's discovery of the period-luminosity relationship for Cepheids, published by Pickering, would prove the foundation for the modern understanding of cosmological distances.

In 1876 he co-founded the Appalachian Mountain Club.

In 1882, Pickering developed a method to photograph the spectra of multiple stars simultaneously by putting a large prism in front of the photographic plate.

He also, along with Williamina Fleming designed a stellar classification system based on an alphabetic system for spectral classes that was first known as the Harvard Stellar Classification and became the basis for the Henry Draper Catalog.

Pickering is credited for making the Harvard College Observatory known and respected around the world, and it continues today to be a well-respected observatory and program.

Awards and honors:

Fellow of the American Academy of Arts and Sciences in 1867.
Gold Medal of the Royal Astronomical Society (1886 and 1901)
Henry Draper Medal from the National Academy of Sciences (1888)
Bruce Medal (1908)

Named after him:

The crater Pickering on the Moon
The crater Pickering Mars.
Asteroid 784 Pickeringia
(all jointly named after him and his brother William Henry Pickering)