APDA and the PARI Library

APDA (Astronomical Photographic Data Archive) & the PARI Library


Acknowledging Those Who Made the Astronomy Legacy Project Possible

For more than 120 years before the advent of digital cameras in the 1990s, astronomers logged several million telescope hours photographing the night sky – measuring star brightness, detecting comets, planets, nebulae, mapping our Galaxy and building the foundations of our understanding of the Universe. All of this raw beauty, and secrets yet to be discovered, are held as largely unexplored photometric, astrometric, spectral and surface brightness images on thin, fragile pieces of glass. Archiving and digitizing the glass photographic plates is the only way to forever preserve these 1,000 terabytes of data acquired and left as a legacy to us by our greatest scientists, those who studied the night sky and gave future explorers a time machine to the past night sky.

The Astronomical Photographic Data Archive (APDA), was established at PARI in 2007 by an international consortium of scientists as a center for collecting, storing, preserving and restoring astronomical photographic data. APDA is also tasked with digitizing these images to establish a database of images that can be accessed via the Internet by the global community of scientists, researchers, students, and interested public. 

APDA is located in the PARI Research Building, the far right building in this photo, just to the left of a 26m radio telescope.

Currently, about 20% of the plates known to exist in North America are housed in APDA and that number grows every year.  The 40 collections in APDA with more than 220,000 images include plates taken for QSO identification, parallax measurements, spectral classification and monitoring, Magellanic Cloud studies, H-alpha emission star surveys, novae evolution, and astrometry of asteroids, outer planet satellites and Pluto.


Books and Journals in the PARI Library

Visiting researchers and students, as well as permanent PARI staff, have access to a large collection of astronomical, physical, and mathematical books and principal journals in astronomy and related sciences.

Through purchase and donations, PARI has been steadily building a collection of journals, textbooks and treatises, and reference works in the physical sciences, mathematics, computer science and engineering. The collection still has many needs, so acquisition will be a continuing effort.

The collection is being consolidated into an library area adjacent to the media center in Building 1. The area is also convenient to professional staff offices and the main antenna control room. Work is already in progress; when complete, the library will have a digital catalog, Internet access, patron reading and desk furniture, shelving for 20,000 volumes and a separate workroom for a librarian.

Books and journals have been donated by a wide variety of people and libraries. Holdings include:

  • The Astronomical Journal (complete from volume 1)
  • The Astrophysical Journal (complete from volume 1)
  • Astronomy and Astrophysics
  • Publicatons of the Astronomical Society of the Pacific
  • Monthly Notices of the RAS
  • Nature
  • Science
  • Journal of Geophysical Research

Electronic cataloging is in process. Organization of general (survey) and introductory monographs by age and knowledge appropriate levels, as designed to serve PARI educational programs, is a convenient feature of each subject matter section.