The NAROO program

The NAROO program has been created at Paris Observatory, Meudon, as a unique centre dedicated to the digitization and the analysis of old astro-photographic plates, mainly for scientific purposes.

The NAROO digitizer consists of a granite-based Newport-Microcontrol open frame air-bearing XY positioning table, a scientific sCMOS camera, and a telecentric optical system. The machine is placed in an overpressure, air-conditioned, ISO-5 clean room to maintain its positioning stability better than 15 nm, and its accuracy better than 65 nm.

The renewed interest about photographic plates concerns the expansion of the database of transient objects evolving in time, since 1) digitization now makes it possible to measure images with a high level of accuracy and to identify all the available objects, 2) the arrival of the Gaia reference catalogs allows to realize reductions for past observations with today accuracy. The information extracted from such materials can be of an astrometric, photometric, and spectroscopic nature, when not purely imaging, with consequences in planetology, near-Earth asteroid risk assessment, astrophysical phenomena, and general relativity, to mention but a few. Since we invite researchers to use our facilities and digitize their collection (free of charge), we detail current and upcoming uses for the community: precoveries, small bodies, planetary satellites, Sun, Be stars, SMC and LMC observations for example.

We will present the results of first mass scans of the Galilean satellites (1967-1998) for which we now reach the limit in accuracy with such observations. We will also present the results of PHA precoveries, up to 60 years before the official discovery date, with consequences on their dynamics.