5.9 KiB
| title | chunk | source | category | tags | date_saved | instance |
|---|---|---|---|---|---|---|
| Harvard Plate Stacks | 1/3 | https://en.wikipedia.org/wiki/Harvard_Plate_Stacks | reference | science, encyclopedia | 2026-05-05T07:09:36.798310+00:00 | kb-cron |
The Harvard Plate Stacks, previously known as the Harvard College Observatory glass plate collection or the astronomical photographic glass plate collection, is a collection of astronomical glass plate negatives at the Center for Astrophysics | Harvard & Smithsonian in Cambridge, Massachusetts. Created over more than a century by the Harvard College Observatory, it is widely described as the largest collection of astronomical glass plates in the world. The collection includes more than 550,000 glass plate negatives dating from the 1870s to the late 1990s, as well as early photographic data from as early as 1849, and logbooks, notebooks, and photographic prints associated with astronomical research at Harvard and affiliated observing stations. It is one of the largest photographic collections at Harvard. Many of the astronomers, assistants, and computers who worked with the collection were women, including members of the group now commonly known as the Women Astronomical Computers.
== Scope and Size == The Harvard Plate Stacks collection consists of over 550,000 glass plate negatives of the night sky. The glass alone is estimated to weigh over 165 tons and stored across three floors of a purpose-built building on Observatory Hill in Cambridge, MA. The majority of the collection consists of the astronomical glass plates negatives, with most of these being gelatin dry-plate negatives. Astronomically, the collection consists of both direct image and spectral plates, with two-thirds of the collection made up of the latter. The collection is also mostly known for its widefield imagery and consists of 20% of the known plates ever taken. The glass plates negatives date from the 1870s to the late 1990s. Any given region of the night sky appears on between 500 and 1,000 plates across a century of time. Both in number of observations and time, the collection will not be surpassed by digitally collected data until projects like the LSST at the Vera Rubin Observatory complete hundreds of observations and until a century of digital CCD imaging in the 2080s. Photographically, the collection spans the history of the analogue photography. While the majority of the collection is photographic negatives, there is a large collection of photographic prints across the same century of time. Archivally, the collection consists of materials like the 2,500 individual notebooks of researchers who were hired to study the plates. These notebooks include those made by some of the most famous astronomers at the Harvard College Observatory including, Williamina Fleming, Antonia Maury, Henrietta Swan Leavitt, Annie Jump Cannon, and Cecilia Payne-Gaposchkin. The Harvard Plate Stacks also hold 1,200 logbooks that record the metadata of each plate, including the time it was created and the observer who made the image.
== Earliest parts of the collection == The collection starts at the dawn of photography with some of the earliest images created of objects in space. These include an early collection of daguerreotypes, including a collection made by photographer John Adams Whipple collaborating with father-son astronomers William Cranch Bond and George Bond. The oldest dated image in the collection is a multiple exposure daguerreotype of the moon made by Samuel Dwight Humphrey on 1 September 1849. This is the second oldest extant image of the moon known to survive, only surpassed by the John William Draper's photograph of the moon now at the New York University Libraries Special Collections.
Photographic firsts contained in the collection include the first photograph of an eclipse (partial) created by Whipple on 28 July 1851 and the first photograph showing the "diamond ring" effect of a total solar eclipse by Whipple in Shelbyville, Kentucky on 7 August 1869. It also includes the first photograph made of a comet made by William Usherwood of the Comet Donati on 27 September 1858, and subsequent exposures made by George Bond on 28 September 1858. While scientifically, photographically, and artistically significant, these earliest photographs were not created consistently. Instead These earliest examples of photography that include daguerreotypes, ambrotypes, wet plate collodion, and salt prints are photographic processes that require more light through longer exposure times than these media would allow to capture all but the brightest objects in the night sky. It was not until the invention of the dry plate negatives as a commercially available medium that the exposure length was no longer limited.
== Anna Palmer Draper, Edward Pickering and the Harvard Computers ==
Following the American Civil War, advances in photography and astronomy allowed for multiple pioneers to make advances in the burgeoning art and science of astrophotography. The British couple, Margaret Lindsay Huggins and William Huggins, would be credited with being the first to experiment using dry plate photography to capture astronomical objects in 1876. At the same time, the American couple, Anna Palmer Draper and Henry Draper, had been experimenting with photography, spectroscopy, and astronomy in their personal observatory in Hastings-on-Hudson, New York. The Drapers would be the first to successfully photograph a spectrum of a star, Vega, in 1872 and be the first to capture the Orion Nebula on September 30, 1880, all with collodion photography. In Massachusetts, the brothers William H. and Edward C. Pickering, would experiment with lenses and start systematically photographing the night sky by 1877. These three pairs of collaborators would exchange correspondences and share discoveries and advancements. On November 20, 1882, Henry Draper dies of "pleurisy" after returning home to New York from a hunting trip in Colorado. In a letter from Edward Pickering to Anna Palmer Draper dated 13 January 1883, he writes,