Astronomical Photographic Research Archive
Discoveries still hide within this vast store of data where skies of the past wait to answer questions of the future.
Astrophysics often seeks to understand phenomena that stretch the limits of what we know, things that cannot be observed here on Earth or replicated in labs, (at least for now!) so we look to the skies. As things in space change, we learn how they work.
Short-term changes in can be studied by making new observations, but many changes happen slowly and need to be observed for years, even decades, to understand them.
Fortunately, astronomical observations beginning in the 1800's were archived and stored on photographic glass plates and film all around the world. There are an estimated one to two million plates in North America alone.
In 2007, a group of 31 international scientists gathered at PARI to develop a plan for the preservation of this astronomical photographic data. They established the Astronomical Photographic Data Archive (APDA) which is dedicated to the task of collecting, restoring, preserving and storing the data. The process includes scanning each image and recording data about what it is and how it was collected. Once scanned it becomes accessible to scientists, researchers, and students around the world.
Many plates contain a vast number of stars and other objects that were never studied by the astronomers who originally collected the data. Researchers today can look back in time with plate collections to reveal the past.
Some collections contain images of the same part of the sky, night after night, for years or decades! Fascinating, important, and ground-breaking data still contains information to be studied. APDA includes plates of the first ultra-violet astronomy ever done, images of the Sun every day for a century, films used to identify near-Earth objects, data used in the creation of all-sky catalogs used by today's space telescopes to aim and position themselves, and more!
New techniques exist today to learn more from the data they contain. AI and Machine Learning give new uses to the collections.
Exoplanets and variables stars can be confirmed. Transient events can be investigated for past occurrences. Countless research opportunities await!
APDA currently includes collections from the following organizations, and more:
From students to space agencies, APDA contains the data needed to grow our understanding of the universe.
Interns pursue projects that lead to posters, papers, and publications, growing their skills, experience, and confidence as they make contributions to astronomy and astrophysics.
Scientists and Researchers use the archive to test how their ideas match historical observations, fill in gaps in data, and grow our understanding of objects and phenomena.
Space agencies and engineers use the data as a training set to make telescopes smarter and more autonomous and increase how efficiently new discoveries can be made.
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