Astronomy and Astrophysics – Astrophysics
Scientific paper
2006-08-01
Astron.J.133:1485-1498,2007
Astronomy and Astrophysics
Astrophysics
14 pages, including 3 figures and 2 tables
Scientific paper
10.1086/511770
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. Using HST/ACS data obtained on 2006 February 15 and 2006 March 2, we find no observational evidence for such a ring system and present the first constraints on the present-day I/F and optical depth of a putative ring system. At the 1500-km radial resolution of our search, we place a 3-sigma upper limit on the azimuthally-averaged normal I/F of ring particles of 5.1x10^-7 at a distance of 42,000 km from the Pluto-Charon barycenter, the minimum distance for a dynamically stable ring (Stern et al., 1994; Nagy et al., 2006); 4.4x10^-7 at the orbit of Nix; and 2.5x10^-7 at the orbit of Hydra. For an assumed ring particle albedo of 0.04 (0.38), these I/F limits translate into 3-sigma upper limits on the normal optical depth of macroscopic ring particles of 1.3x10^-5 (1.4x10^-6), 1.1x10^-5 (1.2x10^-6), 6.4x10^-6 (6.7x10^-7), respectively. Were the New Horizons spacecraft to fly through a ring system with optical depth of 1.3x10^-5, it would collide with a significant number of potentially damaging ring particles. We therefore recommend that unless tighter constraints can be obtained, New Horizons cross the putative ring plane within 42,000 km of the Pluto-Charon barycenter, where rings are dynamically unstable. We derive a crude estimate of the lifetime of putative ring paritcles of 900 years.
Alan Stern S.
Steffl Andrew J.
No associations
LandOfFree
First Constraints on Rings in the Pluto System does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with First Constraints on Rings in the Pluto System, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and First Constraints on Rings in the Pluto System will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-265192