Pulkovo Observatory Collection consists of astronomic photographic negatives (plates) dated from 1893.
Significant part of the collection was lost during the Second World War. The majority of plates was evacuated with all the observatory equipment, but storage conditions were poor due to the war and a lot of plates have been damaged. The remaining part of the Collection was lost under ruins of Observatory. Only about 900 plates dated from 1893 to 1940 had survived all the casualties of the war and we still have all of them in our Collection.
Now the Collection has about 37 000 plates and new arrivals keep coming.
Currently the Collection has plates taken by:
Plates kept in special wooden cabinets. The glue that was used for construction of the cabinets does not contain any chemical active ingredients.
Plates are organized by NGC, ADS numbers or by right ascension.
In order to store information about every plate in the Collection a special database (Electronic Catalog) have been designed and implemented. The project was carried put by the Laboratory of Automation of the Scientific Research (LANI) under management of software engineer Svetlana Cekmeister.
For every plate Electronic Catalog stores the following data fields: telescope model; plate number; plate size; plate scale; plate shape; object name; number by JC, NGC, ADS, IC and other; right ascension (RA); optical center declination (D) of the plate at the moment of observation by epoch J2000.0; time of the beginning and the end of observation; number of exposures; diafragma; filter; star trail ; emulsion; color system; air temperature; air pressure; quality of plate; present condition of the plate emulsion; observer's name; location of the plate in the Collection; name of the observatory where the plate was taken.
Search engine of the Electronic Catalog allows to request search by one or several (group of) data fields. Beside this, search can be made by Celestial coordinates of the selected area or by an object. The result of search is an image of the requested object where every star on the background marked with its number in PPM Catalog.
With the help of the LANI staff Electronic Catalog is constantly updated by the data from new and old plates. By now the Catalog consists of data taken from 15250 plates of Normal Astrograph and 9000 plates of 26' Refractor.