Astrophysics, abstract
astro-ph/0608036

From: Andrew Steffl [view email]

Date: Tue, 1 Aug 2006 20:51:54 GMT (162kb)

First Constraints on Rings in the Pluto System

Authors: A.J. Steffl, S.A. Stern

Comments: 12 pages, including 2 figures and 1 table

Simple theoretical calculations have suggested that small body impacts onto Pluto's newly discovered small satellites, Nix and Hydra, are capable of generating time-variable rings or dust sheets in the Pluto system. We present the first observational constraints on the present-day optical depth of such debris systems using HST/ACS data obtained on 2006 February 15 and 2006 March 2. We find that any Plutonian dust rings between Nix and Hydra must have optical depths of 2x10^(-5) or lower, when averaged over 1000-km radial distance scales. While usefully constraining, the derived ring optical depth limits are still a factor of four higher than those predicted by Stern et al. (2006). Were the New Horizons spacecraft to fly through a ring system with optical depth as high as 2x10^(-5), it would collide with a significant number of potentially damaging ring particles. We therefore recommend that New Horizons cross the potential ring plane at a radial distance where dust rings are not expected due to either dynamical instability or large distance from potential sources of ring particles.

http://arxiv.org/abs/astro-ph/0608036