Bathymetry and absorptivity of Titan's Ontario Lacus

Details Bathymetry and absorptivity of Titan's Ontario Lacus Bathymetry and absorptivity of Titan's Ontario Lacus

Sep 2010

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2010jgre..11509009h&link_type=abstract

Journal of Geophysical Research, Volume 115, Issue E9, CiteID E09009

Physics

5

Planetary Sciences: Solar System Objects: Titan, Planetary Sciences: Solid Surface Planets: Hydrology And Fluvial Processes, Planetary Sciences: Solid Surface Planets: Surface Materials And Properties, Planetary Sciences: Solid Surface Planets: Remote Sensing, Radio Science: Radio Wave Propagation

Scientific paper

Ontario Lacus is the largest and best characterized lake in Titan's south polar region. In June and July 2009, the Cassini RADAR acquired its first Synthetic Aperture Radar (SAR) images of the area. Together with closest approach altimetry acquired in December 2008, these observations provide a unique opportunity to study the lake's nearshore bathymetry and complex refractive properties. Average radar backscatter is observed to decrease exponentially with distance from the local shoreline. This behavior is consistent with attenuation through a deepening layer of liquid and, if local topography is known, can be used to derive absorptive dielectric properties. Accordingly, we estimate nearshore topography from a radar altimetry profile that intersects the shoreline on the East and West sides of the lake. We then analyze SAR backscatter in these regions to determine the imaginary component of the liquid's complex index of refraction ($\kappa$). The derived value, $\kappa$ = (6.1-1.3+1.7) × 10-4, corresponds to a loss tangent of tan Δ = (9.2-2.0+2.5) × 10-4 and is consistent with a composition dominated by liquid hydrocarbons. This value can be used to test compositional models once the microwave optical properties of candidate materials have been measured. In areas that do not intersect altimetry profiles, relative slopes can be calculated assuming the index of refraction is constant throughout the liquid. Accordingly, we construct a coarse bathymetry map for the nearshore region by measuring bathymetric slopes for eleven additional areas around the lake. These slopes vary by a factor of ˜5 and correlate well with observed shoreline morphologies.

Affiliated with

Also associated with

No associations

Rating

Bathymetry and absorptivity of Titan's Ontario Lacus does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Bathymetry and absorptivity of Titan's Ontario Lacus, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Bathymetry and absorptivity of Titan's Ontario Lacus will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1498802