35th Meeting of the AAS Division on Dynamical Astronomy, April 2004
Session 7 Posters II
, Thursday, April 22, 2004, 7:00-8:30pm,

[Previous] | [Session 7] | [Next]

[7.01] Passing the Baton: HST Observations of Pandora and Prometheus on the Eve of Cassini

R.G. French, C.A. McGhee (Wellesley College)

For nearly a decade, the Hubble Space Telescope has provided stunning views of the Saturn system, including hundreds of images of Pandora and Prometheus, two small moons that straddle the F ring. In spite of technological advances in large ground-based telescopes since the launch of the HST, Hubble's WFPC2 is the only near-Earth instrument capable of routine observations of these and other tiny satellites lying just outside of the bright A ring. From earlier HST images, we have shown that Pandora and Prometheus are interacting dynamically (French et al. 2002 Icarus 162, 143-170). Goldreich and Rappaport (2003 Icarus 162, 391-399; 166, 320-327) have demonstrated that their orbits are chaotic, due to interactions associated with the 121:118 mean motion resonance, with particularly strong perturbations at closest approach during the 6.2 year precessional cycle. We have continued to monitor the wanderings of these satellites with the HST, with additional observations scheduled for late March 2004. Not until April of 2004 will the Cassini spacecraft's cameras finally surpass the HST in angular resolution, just before the start of a four year orbital tour of Saturn. We will present a summary of a survey of ten years of HST astrometric observations of Saturn's satellites. This work was supported in part by the NASA PGG program and the Massachusetts Space Grant Consortium. Our results are based on observations with the NASA/ESA Hubble Space Telescope, obtained at the STScI, which is operated by AURU under NASA Contract NAS5-26555.

[Previous] | [Session 7] | [Next]

Bulletin of the American Astronomical Society, 36 #2
© 2004. The American Astronomical Soceity.