CPS researchers, in collaboration with an international team of
colleagues on six Cassini instrument teams report in the March 7, 2008
issue of Science that Saturn's second-largest moon, Rhea, may be
encircled by rings.
CPS Contacts
Dr Geraint Jones
University
College London, Mullard Space Science Laboratory
Tel +44
(0)1483 204 263
[UCL Media
office +44 (0)20 7679 9726; +44 (0)7917271364 out of hours]
ghj@mssl.ucl.ac.uk
Professor Andrew Coates
University College London, Mullard Space Science
Laboratory
Tel +44 (0)7788 448318
ajc@mssl.ucl.ac.uk
G.
H. Jones, E. Roussos, N. Krupp, U. Beckmann, A. J. Coates, F. Crary, I.
Dandouras, V. Dikarev, M. K. Dougherty, P. Garnier, C. J. Hansen, A. R.
Hendrix, G. B. Hospodarsky, R. E. Johnson, S. Kempf, K. K. Khurana, S.
M. Krimigis, H. Krüger, W. S. Kurth, A. Lagg, H. J. McAndrews, D.
G.
Mitchell, C. Paranicas, F. Postberg, C. T. Russell, J. Saur, M.
Seiß,
F. Spahn, R. Srama, D. F. Strobel, R. Tokar, J.-E. Wahlund, R. J.
Wilson, J. Woch, and D. Young Science 7 March 2008
1380-1384.(subscription
required for access to papers)
Supporting
multimedia material
Please do not link directly to files on this page. Files may be posted
elsewhere if credit is used.
Cartoon explaining the interpretation of
the electron data
[Click on
image for full-sized version]
Electron measurements by Cassini’s MIMI instrument as the spacecraft
swept by Rhea on November 26th, 2005. Cassini's path (red), slightly
south of the equator, intersected Rhea’s Hill sphere, shown, where the
moon’s gravitational field dominates. Cassini passed downstream of the
flow of charged particles in Saturn’s magnetosphere (blue), crossing
Rhea's wake (green), where electrons almost disappeared, as expected.
The unusual broad electron decrease on either side of the moon, not
seen elsewhere, was a great surprise. Cassini scientists suggest that
this feature may be evidence for an unobserved equatorial disk of
debris orbiting Rhea. Additional brief dips in electron flow may
indicate the presence of narrow rings within the disk. [Credit:
MPS/MSSL-UCL]
Animation with sound
[Click on image for animation file]
Animation depicting the broad electron depletion near Rhea during 30
minutes, as
Cassini passed the moon on November 26, 2005.
The volume changes reflect the varying amount of electron flux within a
limited energy range.
[Credit:
Animation
by G. Collinson and A. Walsh, MSSL-UCL]
The sound of
electrons near Rhea - signatures of rings around a moon?
This 25-second sound file illustrates how electron fluxes varied during
10 minutes, as Cassini passed Rhea on November 26, 2005. The volume
changes reflect the varying amount of electron flux. At the centre of
the clip is the silence during the crossing of the wake of Rhea. Before
and after than long silence, three brief gaps are heard - the hint of a
ring system? [Credit: MSSL-UCL]
This page
last modified 9 March, 2008
by Geraint Jones
+44 (0)20 7679 2000
- Copyright © 1999-2005 UCL
