The Depth, Composition, and Sea State of Titan’s Mare

Abstract : On August 21st, 2014, the Cassini spacecraft will perform its 104th flyby of Titan. The T104 fly-by will present a unique opportunity to sound the depth of Titan’s largest sea - Kraken Mare, and characterize the sea state of both Kraken and Ligeia Mare. Based on the recent May 2013 (T91) nadir observations of Ligeia Mare, which were used to construct a bathymetric profile and determined the sea’s loss tangent, we expect to detect echoes from both the surface and seafloor of Kraken with the opportunity to derive the depth and composition of this sea. In addition, the T104 observations will be interpreted in the context of wave activity. On Earth, it is rare to observe a body of water whose surface is not disturbed by some form of wave activity. On Titan, Cassini observations through the end of its Equinox Mission in Dec. 2010 showed no indication of waves. These observations are intriguing given the predominance of aeolian features at equatorial latitudes and have been attributed to the light winds predicted during the Titan winter. More recently, however, the previous series of upper limits and non-detections are giving way to indications that the expected freshening of winds in northern summer may be causing sporadic ruffling of the sea surfaces. Specifically, apparent sunglints offset from the geometric specular point has been observed by VIMS in Punga Mare and a transient radar signature, known as Titan’s “Magic Island”, has been observed over the surface of Ligeia Mare. The T104 observation will be acquired at an incidence angle that will either confirm or deny the Magic Island’s transient nature.We will present a summary of the discoveries made during the T104 flyby, which represents one of the most exciting Titan observations of the Cassini mission and has the potential to significantly enhance our understanding of Titan’s methane cycle. The discussion will address the total volume of liquid hydrocarbon contained in Titan’s lakes and seas, the sea state of the Mare as Saturn approaches northern summer, and address the origin of a recent transient feature (the Magic Island) observed in Ligeia Mare in July 2013.
Type de document :
Communication dans un congrès
American Astronomical Society, DPS Meeting , Nov 2014, Tucson, United States. 46, pp.#112.09, 2014
Liste complète des métadonnées

https://hal.archives-ouvertes.fr/hal-01082271
Contributeur : Marie-Paule Pomies <>
Soumis le : jeudi 13 novembre 2014 - 10:18:50
Dernière modification le : jeudi 8 juin 2017 - 15:02:49

Identifiants

Collections

Citation

Alexander Hayes, Marco Mastrogiuseppe, Ralph Lorenz, Jason Hofgartner, Jonathan Lunine, et al.. The Depth, Composition, and Sea State of Titan’s Mare. American Astronomical Society, DPS Meeting , Nov 2014, Tucson, United States. 46, pp.#112.09, 2014. 〈hal-01082271〉

Partager

Métriques

Consultations de la notice

239