Photometry with a periodic grid

D. Hestroffer

doi:doi:10.1051/0004-6361:20030373

Free access

Issue		A&A Volume 403, Number 2, May IV 2003


Page(s)		749 - 756
Section		The Sun
DOI		http://dx.doi.org/10.1051/0004-6361:20030373

A&A 403, 749-756 (2003)
DOI: 10.1051/0004-6361:20030373

II. Results for J2 Europa and S6 Titan

D. Hestroffer

IMCCE, UMR CNRS 8028, Paris Observatory, 77 Av. Denfert Rochereau 75014 Paris, France
(Received 20 December 2002 / Accepted 19 February 2003)

Abstract
The Hipparcos satellite successfully gathered astrometric and photometric information for a few solar system objects including natural satellites. In contrast to the case for asteroids, the Hipparcos main-mission does not provide the photometry - in the conventional sense - of planetary satellites. Nevertheless, valuable photometric results can be obtained, such as a modelling of the centre-to-limb darkening of the bodies. We present in this paper results obtained for the photometry with a periodic grid of the satellites J2 Europa and S6 Titan from the Hipparcos main mission and within the FAST data-reduction Consortium. The Minnaert parameter of S6 Titan is found to be $k\sim0.90\pm0.02$ , and for J2 Europa, $k\sim0.58\pm0.01$ . Brightness variations with orbital phase are also given for Europa.

Key words: planets and satellites: general -- planets and satellites: individual: J2 Europa, S6 Titan