elib
DLR-Header
DLR-Logo -> http://www.dlr.de
DLR Portal Home | Imprint | Privacy Policy | Contact | Deutsch
Fontsize: [-] Text [+]

Titan's lakes and Mare observed by the Visual and Infrared Mapping Spectrometer

Brown, Robert H. and Soderblom, L.A. and Sotin, C. and Barnes, Jason W. and Hayes, A. and Lawrence, K.J. and Le Mouelic, S. and Rodriguez, S. and Soderblom, Jason M. and Baines, K. H. and Buratti, B.J. and Clark, R. N. and Jaumann, R. and Nicholson, P. D. and Stephan, K. (2012) Titan's lakes and Mare observed by the Visual and Infrared Mapping Spectrometer. In: Copernicus. EGU 2012, 22.04-27.04.2012, Wien, Österreich.

[img]
Preview
PDF
38kB

Abstract

Titan is the only place, besides Earth, that holds stable liquid bodies at its surface. The large Kraken Mare, first seen by ISS [1], was then observed by the radar instrument that discovered a large number of small lakes as well as two other Mare [2]. The liquid nature of these radar-dark features was later confirmed by the specular reflection observed by the Visual and Infrared Mapping Spectrometer (VIMS) over Kraken Mare [3] and by the very low albedo at 5-micron over Ontario Lacus [4]. The three largest lakes are called Mare and are all located in the North Pole area. It is remarkable that most of these lakes have been observed on the North Pole with only one large lake, Ontario lacus, located in the South Pole area. This observation suggests the influence of orbital parameters on the meteorology and the occurrence of rainfalls to refill the depressions [5]. Ethane was detected by the VIMS instrument as one component of Ontario lacus [4]. These lakes and Mare play a key role in Titan's meteorology as demonstrated by recent global circulation models [6]. Determining the composition and the evolution of those lakes has become a primary science objective of the Cassini extended mission. Since Titan entered northern spring in August 2009, the North Pole has been illuminated allowing observations at optical wavelengths. On June 5, 2010 the Visual and Infrared Mapping Spectrometer (VIMS) onboard the Cassini spacecraft observed the northern pole area with a pixel size from 3 to 7 km. These observations demonstrate that little of the solar flux at 5-micron is scattered by the atmosphere, which allowed us to build a mosaic covering an area of more than 500,000 km2 that overlaps and complements observations made by the Synthetic Aperture Radar (SAR) in 2007. We find that there is an excellent correlation between the shape of the radar dark area, known as Ligeia Mare and the VIMS 5-micron dark unit. Matching most of the radar shoreline, the 2010 VIMS observations suggest that the 125,000-km2 surface area of Ligeia Mare measured by RADAR in 2007 has not significantly changed [7]. The analysis of the 2-micron spectral window confirms the presence of ethane [8]. Because its saturation vapor pressure is several orders of magnitude smaller than that of methane, liquid ethane is expected to be very stable at Titan's surface conditions, which could explain the stability of the shorelines if ethane is the major compound of the lakes. VIMS observations of Ontario Lacus are planned in 2012 before it disappears in the polar night. Several observations of the northern lakes are planned in 2012 as well as observations of the Mare later in the mission. This work has been performed at the Jet Propulsion Laboratory, California Institute of Technology, under contract to NASA. Government sponsorship acknowledged.

Item URL in elib:https://elib.dlr.de/80544/
Document Type:Conference or Workshop Item (UNSPECIFIED)
Title:Titan's lakes and Mare observed by the Visual and Infrared Mapping Spectrometer
Authors:
AuthorsInstitution or Email of AuthorsAuthors ORCID iD
Brown, Robert H.Lunar and Planetary Laboratory, University of Arizona, Tucson, AZ, USAUNSPECIFIED
Soderblom, L.A.United States Geological Survey, Flagstaff, AZUNSPECIFIED
Sotin, C.University of Nantes, Nantes, FranceUNSPECIFIED
Barnes, Jason W.Lunar and Planetary Laboratory, University of Arizona, Tucson, AZ, USAUNSPECIFIED
Hayes, A.CaltechUNSPECIFIED
Lawrence, K.J.Jet Propulsion Laboratory, Caltech, 4800 Oak Grove Drive, Pasadena, CA 91109, USAUNSPECIFIED
Le Mouelic, S.Laboratoire de Planétologie et Géodynamique, 2 rue de la Houssinière, 44322 NantesUNSPECIFIED
Rodriguez, S.Laboratoire AIM, FranceUNSPECIFIED
Soderblom, Jason M.Department of Planetary Sciences, University of Arizona, Tucson, AZ 85721, USAUNSPECIFIED
Baines, K. H.Jet Propulsion Laboratory, Pasadena, CA, USAUNSPECIFIED
Buratti, B.J.Jet Propulsion Laboratory, Pasadena, CAUNSPECIFIED
Clark, R. N.US Geological Survey, Denver, CO, USAUNSPECIFIED
Jaumann, R.ralf.jaumann (at) dlr.deUNSPECIFIED
Nicholson, P. D.Department of Astronomy, Cornell University, Ithaca, NY, USAUNSPECIFIED
Stephan, K.katrin.stephan (at) dlr.deUNSPECIFIED
Date:April 2012
Journal or Publication Title:Copernicus
Open Access:No
In DOAJ:No
In SCOPUS:No
In ISI Web of Science:No
Status:Published
Keywords:Titan
Event Title:EGU 2012
Event Location:Wien, Österreich
Event Type:international Conference
Event Dates:22.04-27.04.2012
HGF - Research field:Aeronautics, Space and Transport
HGF - Program:Space
HGF - Program Themes:Space Science and Exploration
DLR - Research area:Raumfahrt
DLR - Program:R EW - Erforschung des Weltraums
DLR - Research theme (Project):R - Vorhaben CASSINI (old)
Location: Berlin-Adlershof
Institutes and Institutions:Institute of Planetary Research > Planetary Geology
Deposited By: Aydin, Zeynep
Deposited On:11 Jan 2013 13:53
Last Modified:12 Dec 2013 21:58

Repository Staff Only: item control page

Browse
Search
Help & Contact
Information
electronic library is running on EPrints 3.3.12
Copyright © 2008-2017 German Aerospace Center (DLR). All rights reserved.