Open AccessFirst results from the ionospheric radio occultations of Saturn by the Cassini spacecraft
Author(s) -
Nagy Andrew F.,
Kliore Arvydas J.,
Marouf Essam,
French Richard,
Flasar Michael,
Rappaport Nicole J.,
Anabtawi Aseel,
Asmar Sami W.,
Johnston Douglas,
Barbinis Elias,
Goltz Gene,
Fleischman Don
Publication year - 2006
Publication title -
journal of geophysical research: space physics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.67
H-Index - 298
eISSN - 2156-2202
pISSN - 0148-0227
DOI - 10.1029/2005ja011519
Subject(s) - ionosphere , dusk , zenith , saturn , altitude (triangle) , solar zenith angle , latitude , physics , local time , atmosphere (unit) , atmospheric sciences , astrobiology , astronomy , spacecraft , magnetosphere of saturn , radio occultation , geology , magnetosphere , geodesy , planet , meteorology , magnetopause , plasma , statistics , geometry , mathematics , quantum mechanics
The first set of near‐equatorial occultations of the Saturn ionosphere was obtained by the Cassini spacecraft between May and September of 2005. The occultations occurred at near‐equatorial latitudes, between 10°N and 10°S, at solar zenith angles from about 84° to 96°. The entry observations correspond to dusk conditions and the exit ones to dawn. An initial look at the data indicates that the average peak densities are lower and the peak altitude higher at dawn than at dusk, possibly the result of ionospheric decay during the night hours. There are also significant differences between individual dawn and dusk occultations; the initial thought is that this variation must be connected to changes in the water inflow into the upper atmosphere and/or variations in the particle impact ionization rates.