United States Naval Observatory


19th and 20th century astronomy and physics


Since its founding in 1841, the US Naval Observatory has amassed culturally and scientifically significant materials relevant to the study of the intellectual, social and cultural history of the United States and beyond. As one of the most complete astronomical collections in the country, the USNO Library has important resources for the investigation into the history of science and technology. These resources can and should facilitate investigations into the dramatic changes in the fields of astronomy and physics, particularly in the 19th and 20th century.
The USNO Library’s unique environment makes it an exceptional place for the study of the history of science. Researchers will be able to see the historic scientific instruments they study still in use, like the 26-inch refractor telescope which was used by USNO staff astronomer Asaph Hall for the discovery of the Moons of Mars in 1877. Scientific instruments, however, are only a small part of the collection. Hundreds of manuscript observation notebooks, detailing the nightly observations of astronomers since the mid-19th century, are available for research, as are the notebooks from the several 19th-century Transit of Venus expeditions organized by the Naval Observatory to such far-flung locations as Vladivostok and Santa Cruz. 
The 800-volume rare book collection, dating from 1482 to 1799, consists of the foundational texts in the history of astronomy, and our larger 19th-century scientific monograph collection is ripe for study. Perhaps most essential to the study of the history of science is the scientific periodicals collection, originating from across the globe and dating from the early 17th century to today.


Collections URL

Holding Highlights

  • 800 volume rare book collection
  • 19th century scientific monograph collection
  • Tens of thousands of scientific periodicals originating from across the globe dating from the early 17th century to today