Ultraviolet imaging spectroscopy shows an active saturnian system.
Neutral oxygen in the saturnian system shows variability, and the total number of oxygen atoms peaks at 4 x 10(34). Saturn's aurora brightens in response to solar-wind forcing, and the auroral spectrum resembles Jupiter's. Phoebe's surface shows variable water-ice content, and the data indicate it originated in the outer solar system. Saturn's rings also show variable water abundance, with the purest ice in the outermost A ring. This radial variation is consistent with initially pure water ice bombarded by meteors, but smaller radial structures may indicate collisional transport and recent renewal events in the past 10(7) to 10(8) years.
Esposito
Larry W
LW
University of Colorado, Laboratory for Atmospheric and Space Physics, 234 Innovation Drive, Boulder, CO 80303-7814, USA. larry.esposito@lasp.colorado.edu
Colwell
Joshua E
JE
Larsen
Kristopher
K
McClintock
William E
WE
Stewart
A Ian F
AI
Hallett
Janet Tew
JT
Shemansky
Donald E
DE
Ajello
Joseph M
JM
Hansen
Candice J
CJ
Hendrix
Amanda R
AR
West
Robert A
RA
Keller
H Uwe
HU
Korth
Axel
A
Pryor
Wayne R
WR
Reulke
Ralf
R
Yung
Yuk L
YL
D005118:Extraterrestrial Environment; D006859:Hydrogen; D007053:Ice; D010100:Oxygen; D018539:Saturn; D018531:Spacecraft; D013057:Spectrum Analysis; D014466:Ultraviolet Rays; D014867:Water
D007053:Ice; D014867:Water; D006859:Hydrogen; D010100:Oxygen