Abstract
Results of the observations of mutual eclipses of Galilean satellites observed from the Vainu Bappu Observatory during 1985 are presented. Theoretical models assuming a uniform disc, Lambert’s law and Lommel-Seeliger’s law describing the scattering characteristics of the surface of the eclipsed satellite were used to fit the observations. Light curves of the 1E2 event on 1985 September 24 and the 3E1 event on 1985 October 24 observed from VBO and published light curves of the 1E2 event on 1985 September 14, the 3E1 event on 1985 September 26 and the 2E1 event on 1985 October 28 (Arlotet al 1989) were fitted with theoretical light curves using Marquardt’s algorithm. The best fitting was obtained using Lommel-Seeliger’s law to describe the scattering over the surface of Io and Europa. During the fitting, a parameterδxshift which shifts the theoretical light curve along the direction of relative motion of the eclipsed satellite with respect to the shadow centre, on the sky plane (as seen from the Sun) was determined along with the impact parameter. In absence of other sources like prominent surface features or non perfect sky conditions which could lead to asymmetric light curves,δxshift would be a measure of the phase correction (Aksnes, Franklin & Magnusson 1986) with an accuracy as that of the midtime. Heliocentric Δα cos (δ) and gDδ at mid times derived from fitted impact parameters are reported
Similar content being viewed by others
References
Aksnes, K. A. 1974,Icarus,21, 100.
Aksnes, K. A., Franklin, F. 1976,Astr. J.,81, 464.
Aksnes, K. A., Franklin, F. 1984,Icarus,60, 180.
Aksnes, K. A., Franklin, F., Magnusson, P. 1986,Astr. J.,92, 1436.
Arlot, J.-E., Camichel, H., Link, F. 1974,Astr. Astrophys.,35, 115.
Arlot, J.-E., 1982,Astr. Astrophys.,107, 305
Arlot, J.-E., 1984,Astr. Astrophys.,138, 113.
Arlot, J.-E., Bouchet, P., Gouiffes, C. H., Schmider, F. X., Thuillot, W. 1989,Astr. J.,98, 1890.
Bevington, P. R. 1969,Data Reduction and Error Analysis for the Physical Sciences, New York, Chapter 11, McGraw-Hill.
Galilean Satellite Observers 1990,Astr. J., (in press).
Lieske, J. H. 1980,Astr. Astrophys.,82, 340.
Lieske, J. H. 1987,Astr. Astrophys.,176, 146.
Morrison, D. 1982 inSatellites of Jupiter, Ed. D. Morrison, Univ. Arizona press, pp. 3–37.
Surdej, A., Surdej, J. 1978,Astr. Astrophys.,66, 31.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Vasundhara, R. Mutual phenomena of Jovian satellites. J Astrophys Astron 12, 69–87 (1991). https://doi.org/10.1007/BF02709773
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF02709773