ReTrOH-UNLP: Conservation of the Historical Observational Work of the Astronomical Observatory of La Plata with Computer Vision

Abstract

The Observatorio Astronómico de La Plata from the Facultad de Ciencias Astronómicas y Geofísicas (FCAG) of the Universidad Nacional de La Plata (UNLP) is one of the oldest observatories in South America. It has an enormous collection of observations, including thousands of spectroscopic and photographic glass plates. These observations were taken between the 1900s and the 1980s by renowned Argentine astronomers and constitute unique and unpublished records.Since 2019, the Recuperation of Historical Observational Work (ReTrOH, for its initials in Spanish) project has begun digitizing the 15,000+ samples of the spectroscopic plate collection.The digitization process for each plate is a complex, error-prone, multi-stage procedure requiring several person-hours. Consequently, a multidisciplinary team of astronomers and computer scientists was formed to develop the first system capable of assisting the user in this process. This system, designated PlateUNLP, employs signal processing algorithms and computer vision models to accelerate the process, reduce error rates, and standardizes data formats and processes. A key feature of PlateUNLP is its ability to automatically detect and record each spectrum recorded on the plates, along with the corresponding metadata, thus minimizing the need for user intervention.The developed system is publicly available under an open source license. Furthermore, while the system was developed with the ReTrOH project´s requirements in mind, it could be adapted and used to assist with the digitization of thousands of other plates available around the world.PlateUNLP is therefore a first step towards making possible and practical the recovery of historical astronomical observations. Digitizing and exploiting these observations can provide a unique window into the past of our universe.