Update from Saturn After Cassini-Huygens
I’ve been off-line for a bit due to a combination of European travel, interrupted internet access, and illness. We’re just finishing up the Symposium “Saturn After Cassini-Huygens” at Imperial College in London. The symposium is linked to a book of the same name that will be published in mid-2009. I’m the lead author on the chapter on the structure of Saturn’s rings. Others have the more difficult task of explaining that structure. Of course, Cassini is now into its “Equinox Mission” which runs through mid-2010, so the “After” in the title of the book is a bit misleading.
The big news from Cassini this week is the confirmation that there is liquid on the surface of Titan. The lake was identified by the spectral signature of liquid ethane which is in solution with methane and other compounds in the lake in Titan’s south polar region. Suspected to be a lake based on its appearance, this confirms it is in fact liquid, making Titan only the second object after Earth to have stable liquid on the surface. Many other suspected lakes exist in the north polar region where it is currently late winter. Those were identified by radar measurements, while the new identification comes from the Cassini Visual and Infrared Mapping Spectrometer (VIMS). Future observations as Cassini continues its mission should identify more lakes.
The more distant future may see more dramatic observations as both NASA and ESA are considering major missions dedicated to Titan exploration.