Titan Focus Group
Jonathan Lunine, Chair
University of Arizona
External Link: Titan Focus Group Website
Since the discovery of a methane atmosphere around Titan by Gerard Kuiper in 1944, Titan has been a world that has attracted much exobiological interest. Titan provides us with a planet-sized laboratory for testing the synthesis of organic compounds in a nearly neutral redox environment, over large spatial scales, both with and without liquid water. These natural chemical experiments could be ongoing today, and the products of such experiments in localized regions of elevated temperatures would be well preserved under the ambient 95 K temperatures and high atmospheric densities that shield the surface from destructive radiation.
The Titan Focus Group (TFG) was initiated in November 2002. It is open to all interested parties, but all individuals who desire to participate are asked to identify themselves, their institution, and to commit to a certain amount of time and activity. Most of the work of the group is by e-mail, but two or three meetings of the focus group are organized around convenient ancillary meetings (such as the NAI annual meeting).
A major Titan mission—Titan Planetary Explorer (or TiPEx) has been studied at JPL under the PI-ship of Jonathan Lunine (Titan Focus Group chair). Other focus group member who participated were Ralph Lorenz (UA), Pat Beauchamp (JPL), Jack Beauchamp (Caltech). The study evaluated the scientific rationale for and technical feasibility after Cassini of a hot air balloon that would operate at 10 km above the surface of Titan, making observations and dipping down occasionally to retrieve a sample for onboard analysis. The lifetime of the balloon is not limited by buoyancy; a long-lived radioisotopic power source for the gondola provides a heat source and altitude is controlled by a valve in the balloon. The balloon, therefore, could circumnavigate Titan in the zonal winds, blown slowly across latitude lines by slower meridional breezes. An orbiter could enhance communications rates and provide global context, but is not necessary.
A parallel study by Ed Sittler (Goddard) and colleagues has also looked at Titan aerial vehicles beyond Cassini. Both of these studies have been informed and partly motivated by the NAI Titan Focus Group discussions regarding the astrobiology of Titan. A descriptive version of the JPL study, in pdf form, will be made available to the NAI website in 2006.
The TFG Chair Jonathan Lunine was on sabbatical in Rome for the entire 2005 year, and so the group did not meet. However, several members of the group including Dr. Lunine participated in NASA Visions mission studies for future Titan missions and presented their results at the Outer Planets Assessment Group (OPAG) meeting in Washington DC October 6-7, 2005.
The Titan photochemical website went live and is curated by Professor R. Minard. http://psarc.geosc.psu.edu/TITAN/index.html
The group will reactivate when Dr. Lunine’s sabbatical concludes in June, 2006.
The TFG met at NASA Ames this year after the AbSciCon 2004. A summary of the meeting is appended. It was decided to attempt the construction of a website for laboratory photochemical data to be used in analyzing Cassini data beginning late this year. Dr. Robert Minard of Penn State has agreed to begin this process.
Cassini-Huygens reached Saturn orbit on June 30, 2004. Several TFG members are Science Team Members for the mission. NASA also initiated two future Titan studies, one of which involves individuals from the Focus Group as PIs and collaborators. A member of TFG is the Project Investigator for the Titan Organics Explorer.
Our first topical area was tackled at the NAI conference in Tempe, AZ in February 2003. A map of potential questions to be addressed by a follow-on Titan mission was sketched, and will be worked on further this fall. Arrangements for a conference on future Titan missions to be held in Tucson were made in coordination with Cassini Project personnel, and will highlight Focus Group discussions.