Accession Number : ADA545808


Title :   A New Astrometric Reduction of Photographic Plates Using the DAMIAN Digitizer: Improving the Dynamics of the Jovian System


Descriptive Note : Journal


Corporate Author : NAVAL OBSERVATORY WASHINGTON DC


Personal Author(s) : Robert, V ; De Cuyper, J ; Arlot, J ; de Decker, G ; Guibert, J ; Lainey, V ; Pascu, D ; Winter, L ; Zacharias, N


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a545808.pdf


Report Date : Jan 2011


Pagination or Media Count : 9


Abstract : The astrometric monitoring of the natural planetary satellites is an important step to assess the formation and the evolution of these systems. However, in order to quantify relevant gravitational effects such as tidal forces, it is necessary to have very accurate observations over a long time interval. Unfortunately, the accuracy is decreasing as one considers older observations. To solve this issue, digitizing of old photographic plates is an attractive method, but a high accuracy in the measurement and the reduction of those plates is absolutely necessary. We have developed methods and algorithms adapted to specific plates provided by USNO, using the DAMIAN digitizer of ROB. From a set of 35 plates taken in 1974, we have been able to produce measurements with an accuracy better than 0.08 micrometers and after reduction using the UCAC2 catalogue, rms residuals of 35 mas (1.7 micrometers) for intersatellite positions (when the original reduction provided 100 mas) and of 65 mas for equatorial RA and Dec. positions (which were not possible to get with the original reduction). First results on the dynamics of the satellites and of the planet Jupiter are provided.


Descriptors :   *PLANETARY SATELLITES , *MONITORING , DYNAMICS , ACCURACY , LONG RANGE(TIME) , REDUCTION , PLATES , GRAVITY , ASTRONOMY , ANALOG TO DIGITAL CONVERTERS , PHOTOGRAPHIC PLATES , PLANETS , JUPITER(PLANET) , REPRINTS , ALGORITHMS , TIME INTERVALS


Subject Categories : Astronomy


Distribution Statement : APPROVED FOR PUBLIC RELEASE