The North American Astronomical Photographic Plate Center Session Wednesday, June 2, th Meeting of the American Astronomical Society A Not-for-Profit Public Foundation J. D. Cline, M. W. Castelaz, T. Crowley (PARI) E. Griffin (DAO) W. Osborn (CMU)

One-Minute Overview  Observations in digital form have become an essential element of modern astronomical research.  At present, generally only recent observations are available digitally - the rich older collections of observations are largely available only on archived photographic plates.  These photographs constitute an enormously important and, for the large part, unrepeatable resource for research, but many plate archives are currently being neglected and their information may be lost.  International concurrence is mounting to rescue, preserve and catalog the plates, and to preserve their information through digitization. Digitization permits development of an easily accessible public database of images and spectra for worldwide retrieval and use.  The task of digitizing the photographic material is large but uncomplicated, and is fully feasible with modern technology.

Is digitizing old plates worth the effort? A few examples of research based on archived plate collections  Gamma Ray Bursts Historical Data  Long-term Star Variability  Re-analysis of old observations of currently interesting object that include: Near-Earth Asteroids BL Lac Objects Novae

What is being done to preserve and digitize astronomical plates A number of projects of plate preservation and digitization are currently active. These are summarized in Table 1. ProjectURLLocation IAU Preservation & Digitization of Photographic Plates Working Group pp.html UCCLE Direct Astronomical Plate Archive Centre udapac.oma.be/~fido/ovid.htmlRoyal Observatory of Belgium Wide-Field Plate Database of Astronomy Bulgarian Academy of Sciences Spectroscopic Virtual Observatory html Dominion Astrophysical Observatory The Plate Collection of the Nantucket Maria Mitchell Association plates.htm Maria Mitchell Association 4 Vestal St., Nantucket, MA Table 1. Some Examples of Plate Preservation & Digitization Projects

The Center is Being Developed in Four Phases: I.Acquisition, Storage and Indexing II.Local Measurements and Linking with Other Plate Libraries III. Digitization IV.Web Image Database The Pisgah Astronomical Research Institute (PARI) is the home to a new initiative, called the North American Center of Astronomical Photographic Plate Preservation. The goal is to be a collection, preservation, and distribution center for digitized images of astronomical plates

Why a Center at PARI? PARI is a natural home for a plate archive, offering physically secure and abundant environmentally controlled space PARI is well suited to serve as a distribution center for digitized images, provide available space and Internet 2 infrastructure. The Center at PARI is also a long-term repository for unwanted direct and objective prism plate collections currently stored in North America, complementing the work of the Spectroscopic Virtual Observatory (DAO, Canada), whose focus is digitizing slit spectra plates from archives worldwide.

Pisgah Astronomical Research Institute PARI is a not-for-profit public foundation dedicated to providing research and educational access to radio and optical astronomy for a broad cross-section of users. PARI is located on 200 acres in the Pisgah National Forest in western North Carolina The PARI Campus is relatively free of light and radio interference. N

PARI Meets the Requirements for Facilities and Storage Area  A secure area with controlled access  Backup power for the entire site  Location with small probability of flood, earthquake, or fire  Several thousand square feet of floor space  A clean, relative dust-free environment with control of humidity, temperature and protection from direct sunlight  Space for a high resolution scanner and densitometer  A solid foundation for the digitizing instrument  High speed internet access  Space for servers and storage media

Funding Requirements To fully function as a world-wide distribution center of digitized data from astronomical plates, the Plate Center at PARI requires funding for: Personnel Acquisition of plates A scanner Data storage and Network Electricity, Heating, Humidity and air conditioning Those preserving their plate collections at PARI are asked to work with the PARI staff to seek grants and donations for funding to support effort.

1. Acquisition A. Contact PARI with the following information: 1.Number of plates 2.Plate Dimensions 3.Type: Objective Prism or Direct 4.Observatory and Telescope used 5.Plate observer/author/log book 6.Sky Coverage 7.Storage for Plates 8.Coordination of shipping of plates: a. Schedule for Shipping b. Costs and Funding PHASE I

B. Ship plates to PARI 1. Box Plates a.Align plates neatly against each other within their box to eliminate side-to-side movement of individual plates b.Insert corrugated cardboard filler to prevent side-to-side plate movement or end-to-end shifting 2. Transportation a.Use trucks with air ride suspensions if at all possible b.Stack boxes no more than two high 3. Items to be included with plates: Copy of Logs Cabinets/shelves 4. Plates will be stored at the Center in their original cabinets if available

2.Relevant information is catalogued and indexed on the Internet Relevant Information for the Index Observatory and telescope Plate observer/author Plate center coordinates (RA-DEC) from center of plate “Equinox” Object/field name and Unique plate identifier Filter used Date (yyyymmdd) Beginning of exposure time in UTC Continued…

Duration of the exposure in seconds Emulsion type Plate size Multiplicity of the exposure Object prism indicated Temperature and humidity Seeing and transparency Plate quality Image Quality Notes/remarks 3. Secure Long Term Funding To be an archival resource harnessed by present and future generations of astronomers To be a resource for Earth and Atmospheric Sciences, as well as History of Science.

PHASE II Local Measurements and Linking to Other Plate Libraries  Measuring machines currently at PARI include (Thanks to Vanderbilt University)  Grant Line Measuring Comparator  Becker Iris Diaphram Photometer  Acquire other measuring machines  Setup lab space to include  Internet connection  Table and desk space  Document scanner  Temperature and humidity control  Easy physical access to plates

PHASE III Digitization Plate Digitization Requirements Digitizer Requirements Scanning resolution similar to resolution of a photographic plate Preserve astrometric precision of the plate Data Storage Requirements Potentially 3,000,000 plates Subscribe to the Astronomical Photographic Plate Listerserver. Go to

Funding will support Personnel Acquisition of plates A scanner Computer and data storage Electricity Network connection fees Heating and air conditioning Phase IV will be digitization and development of a public web accessible database of images. Begin service of higher resolution scanning per astronomer request. Continue to acquire plates Increase Center staff PHASE IV