Astrometric results of observations of mutual occultations and eclipses of the Saturnian satellites in 2009^⋆

¹ Institut de mécanique céleste et de calcul des éphémérides – Observatoire de Paris, UMR 8028 du CNRS, 77 Av. Denfert-Rochereau, 75014 Paris, France
e-mail: arlot@imcce.fr
² Sternberg astronomical institute, 13 Universitetskij prospect, 119992 Moscow, Russia
e-mail: emelia@sai.msu.ru
³ Terskol Observatory, Kabardino-Balkaria Republic, 361605, Russian Federation
⁴ Institut de Ciéncies de l’Espai (IEEC-CSIC), Campus UAB, Facultat de Ciéncies, Torre C5 parell, 08193 Bellaterra, Spain
⁵ Armagh Observatory, College Hill, Armagh BT61 9DG, UK
⁶ 20 rue Jean Monnet, 78180 Montigny-le-Bretonneux, France
⁷ Université de Bordeaux, Observatoire Aquitain des Sciences de l’Univers, CNRS, UMR 5804, Laboratoire d’Astrophysique de Bordeaux, 2 rue de l’observatoire, BP 89, 33271 Floirac Cedex, France
⁸ Sparta Astronomical Society, Sparta, Greece
⁹ 22 Booker Road, 2777 Hawkesbury Heights, Australia
¹⁰ 136 Rio Senda, Umatilla, Oregon, 97882, USA
¹¹ Paris Observatory, place J. Janssen, 92190 Meudon, France
¹² 14 Craigieburn Street, 7510 Darfield, New Zealand
¹³ c/ Anselm Clav, 14, 08635 Sant Esteve Sesrovires, Catalonia, Spain
¹⁴ Universidad de Monterrey, Departamento de Física y Matemáticas Av. I. Morones Prieto 4500 Pte, San Pedro Garza García, N.L., CP 66238, México
¹⁵ Yunnan Observatory, PR China
¹⁶ St. Patrick’s Grammar School, Cathedral Road, Armagh BT61 7QZ, UK
¹⁷ St. Louis Grammar School, 151 Newry Road, Kilkeel BT34 4EU, UK
¹⁸ Pulkovo Observatory, Saint Petersburg, Russia
¹⁹ 3 Lupin Pl, Murrumbateman, NSW 2582, Australia
²⁰ Ellinogermaniki Agogi School Observatory, Pallini Attikis, Athens, Greece
²¹ Observatório Nacional/MCTI, rua Gal. J. Cristino 77, Rio de Janeiro, Brazil
²² Department of Physics, Universidad de La Serena, Cisternas 1200 La Serena, Chile
²³ Observatorio do Valongo/UFRJ, Ladeira Pedro Antonio 43, Rio de Janeiro, Brazil
²⁴ Agrupació Astronómica de Sabadell, PO Box 50, 08200 Sabadell, Spain

Received: 23 November 2011
Accepted: 10 April 2012

Abstract

Context. The photometry of mutual occultations and eclipses of natural planetary satellites can be used to infer very accurate astrometric data. This can be achieved by processing the light curves of the satellites observed during international campaigns of photometric observations of these mutual events.

Aims. This work focuses on processing the complete database of photometric observations of the mutual occultations and eclipses of the Saturnian satellites made during the international campaign in 2009. The final goal is to derive new accurate astrometric data.

Methods. We develop an accurate photometric model of mutual event observations of sufficiently high accuracy. Our original method is applied to derive astrometric data from photometric observations of the mutual occultations and eclipses of the Saturnian satellites.

Results. We process the 26 light curves obtained during the international campaign of photometric observations of the Saturnian satellites in 2009. Compared with the theory TASS 1.7 by Vienne and Duriez, we find that the root mean square of the “O–C” residuals for the 23 highest quality observations are equal to 48.5 and 21.7 mas in right ascension and declination, respectively, we obtain 16.4 and 20.7 mas with the new theory by Lainey and collaborators and 17.3 and 21.6 mas with JPL SAT351 ephemerides. Topocentric or heliocentric angular differences for satellites pairs are obtained for 16 time instants during the time period from December 19, 2008 to July 16, 2009.