Between 2004 and 2009 the RADAR instrument of the Cassini mission provided 31 SAR images of Titan. We tracked the position of 160 surface landmarks as a function of time in order to monitor the rotational dynamics of Titan. We generated and processed RADAR observables using a least squares fit to determine the updated values of the rotational parameters. We provide a new rotational model of Titan, which includes updated values for spin pole location, spin rate, precession and nutation terms. The estimated pole location is compatible with the occupancy of a Cassini state 1. We found a synchronous value of the spin rate (22.57693 deg/day), compatible at a 3- σlevel with IAU predictions. The estimated obliquity is equal to 0.31 °, incompatible with the assumption of a rigid body with fully-damped pole and a moment of inertia factor of 0.34, as determined by gravity measurements.
The rotational dynamics of titan from Cassini radar images / Meriggiola, Rachele; Iess, Luciano; Stiles, B. r. y. a. n. W.; Lunine, J. o. n. a. t. h. a. n. I.; Mitri, Giuseppe. - In: ICARUS. - ISSN 0019-1035. - STAMPA. - 275:(2016), pp. 183-192. [10.1016/j.icarus.2016.01.019]
The rotational dynamics of titan from Cassini radar images
MERIGGIOLA, RACHELE
;IESS, Luciano;
2016
Abstract
Between 2004 and 2009 the RADAR instrument of the Cassini mission provided 31 SAR images of Titan. We tracked the position of 160 surface landmarks as a function of time in order to monitor the rotational dynamics of Titan. We generated and processed RADAR observables using a least squares fit to determine the updated values of the rotational parameters. We provide a new rotational model of Titan, which includes updated values for spin pole location, spin rate, precession and nutation terms. The estimated pole location is compatible with the occupancy of a Cassini state 1. We found a synchronous value of the spin rate (22.57693 deg/day), compatible at a 3- σlevel with IAU predictions. The estimated obliquity is equal to 0.31 °, incompatible with the assumption of a rigid body with fully-damped pole and a moment of inertia factor of 0.34, as determined by gravity measurements.File | Dimensione | Formato | |
---|---|---|---|
Meriggiola_the-rotational-dynamics_2016.pdf
solo gestori archivio
Tipologia:
Versione editoriale (versione pubblicata con il layout dell'editore)
Licenza:
Tutti i diritti riservati (All rights reserved)
Dimensione
1.57 MB
Formato
Adobe PDF
|
1.57 MB | Adobe PDF | Contatta l'autore |
I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.