Close Cassini flybys of Saturn's ring moons Pan, Daphnis, Atlas, Pandora, and Epimetheus

B J Buratti; P C Thomas; E Roussos; C Howett; M Seiß; A R Hendrix; P Helfenstein; R H Brown; R N Clark; T Denk; G Filacchione; H Hoffmann; G H Jones; N Khawaja; P Kollmann; N Krupp; J Lunine; T W Momary; C Paranicas; F Postberg; M Sachse; F Spahn; J Spencer; R Srama; T Albin; K H Baines; M Ciarniello; T Economou; H-W Hsu; S Kempf; S M Krimigis; D Mitchell; G Moragas-Klostermeyer; P D Nicholson; C C Porco; H Rosenberg; J Simolka; L A Soderblom

doi:10.1126/science.aat2349

Close Cassini flybys of Saturn's ring moons Pan, Daphnis, Atlas, Pandora, and Epimetheus

Science. 2019 Jun 14;364(6445):eaat2349. doi: 10.1126/science.aat2349. Epub 2019 Mar 28.

Authors

B J Buratti¹, P C Thomas², E Roussos³, C Howett⁴, M Seiß⁵, A R Hendrix⁶, P Helfenstein², R H Brown⁷, R N Clark⁶, T Denk⁸, G Filacchione⁹, H Hoffmann⁵, G H Jones¹⁰, N Khawaja^{8

11}, P Kollmann¹¹, N Krupp³, J Lunine², T W Momary¹², C Paranicas¹³, F Postberg^{8

11}, M Sachse⁵, F Spahn⁵, J Spencer⁴, R Srama¹⁴, T Albin¹⁴, K H Baines¹², M Ciarniello⁹, T Economou¹⁵, H-W Hsu¹⁶, S Kempf¹⁶, S M Krimigis¹³, D Mitchell¹³, G Moragas-Klostermeyer¹⁴, P D Nicholson², C C Porco¹⁷, H Rosenberg⁸, J Simolka¹⁴, L A Soderblom¹⁸

Affiliations

¹ Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA. [email protected].
² Cornell Center for Astrophysics and Planetary Science, Cornell University, Ithaca, NY 14853, USA.
³ Max Planck Institute for Solar System Research, 37077 Göttingen, Germany.
⁴ Southwest Research Institute, Boulder, CO 80302, USA.
⁵ Department of Physics and Astronomy, University of Potsdam, 14476 Potsdam, Germany.
⁶ Planetary Sciences Institute, Tucson, AZ 85719, USA.
⁷ Lunar and Planetary Lab, University of Arizona, Tucson, AZ 85721, USA.
⁸ Institute of Geological Sciences, Freie Universität Berlin, 12249 Berlin, Germany.
⁹ Istituto Nazionale di Astrofisica, Rome, Italy.
¹⁰ University College London, London, UK.
¹¹ Institute of Earth Sciences, University of Heidelberg, 69120 Heidelberg, Germany.
¹² Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA.
¹³ Applied Physics Laboratory, Johns Hopkins University, Laurel, MD 20723, USA.
¹⁴ University of Stuttgart, 70569 Stuttgart, Germany.
¹⁵ Enrico Fermi Institute, University of Chicago, Chicago, IL 60637, USA.
¹⁶ Physics Department, University of Colorado, Boulder, CO 80303, USA.
¹⁷ Space Sciences Institute, Boulder, CO 80301, USA, and Department of Astronomy, University of California, Berkeley, CA 94720, USA.
¹⁸ U.S. Geological Survey, Flagstaff, AZ 86001, USA.

PMID: 30923171
DOI: 10.1126/science.aat2349

Abstract

Saturn's main ring system is associated with a set of small moons that either are embedded within it or interact with the rings to alter their shape and composition. Five close flybys of the moons Pan, Daphnis, Atlas, Pandora, and Epimetheus were performed between December 2016 and April 2017 during the ring-grazing orbits of the Cassini mission. Data on the moons' morphology, structure, particle environment, and composition were returned, along with images in the ultraviolet and thermal infrared. We find that the optical properties of the moons' surfaces are determined by two competing processes: contamination by a red material formed in Saturn's main ring system and accretion of bright icy particles or water vapor from volcanic plumes originating on the moon Enceladus.

Publication types

Research Support, Non-U.S. Gov't