Predictions of the events of the satellites of Saturn during the 2009 equinox*
Institut de mécanique céleste et de calcul des éphémérides – Observatoire de Paris, UMR 8028 du CNRS, 77 avenue Denfert-Rochereau, 75014 Paris, France, USTL, Lille, UPMC, Paris, France e-mail: [arlot;thuillot]@imcce.fr
Accepted: 19 March 2008
Aims. The Saturnian equinox will occur in 2009; i.e., the Sun (and the Earth, very close to the Sun as seen from Saturn) will be in the equatorial plane of Saturn. Eclipses of the satellites by Saturn or mutual eclipses and occultations will occur among the seven first satellites orbiting in the Saturnian equatorial plane. This paper provides predictions of these events, along with information useful for observing them. Such events are uncommon, since they only occur every 15 years during the Saturnian equinox. The present dynamical models of motion of the Saturnian satellites include many effects on their motion. One needs accurate observations, such as mutual events, to determine all the relevant parameters.
Methods. For these predictions, we used the best theoretical models of the motion of the satellites, since the prediction of events is very sensitive to the accuracy of the relative calculated positions of the satellites.
Results. Therefore, we encourage professional and amateur astronomers to join the observers network to get as many observations as possible. Data on the predictions of the events and interactive software for their visibility are available on the web server of the IMCCE (www.imcce.fr/phemu09).
Key words: astrometry / occultations / eclipses / celestial mechanics / planets and satellites: individual
© ESO, 2008