Ocean acoustic circumpropagation in the ice seas of Europa

• Main Authors: Leighton, T.G., Finfer, D.C., White, P.R.
• Format: Book
• Language: English
• Published: University of Southampton 2007
• Subjects: Ice Sheet
• Online Access: https://eprints.soton.ac.uk/50495/; https://eprints.soton.ac.uk/50495/1/Pub10140.pdf

In recent years increased attention has been paid to the potential uses of acoustics for extraterrestrial exploration. A number of important papers have discussed propagation on Europa, primarily with respect to sound in the ice sheet which is believed to cover a salt water ocean. The models used to date assume a flat ice surface and a gravitational acceleration which does not vary with depth. Models of long range acoustic propagation through Europa’s ice seas require models which do not make these two assumptions. This report applies such a model to simple Europan geometries to show how observables can be affected by the values of physical parameters: the report considers the specific case of the effect on the travel time of a circumpropagating pulse of the ice and water thicknesses, and water temperature (assumed to be uniform), on a simple spherical planet. Such effects could be the basis of acoustic inversion experiments, although it is recognised that the complexities and uncertainties associated with the actual ice seas of Europa would make the task very much more challenging than the calculations undertaken in this simple study.