[X] My Assistant

[Mark6]

Today I heard this on NPR: Exploring a moon by boat

The mission could launch around 2016 and be sailing on Titan around 2022 — if this team gets through a highly competitive selection process to get funding from NASA. Stofan and her colleagues are busy working up their proposal for when NASA begins to accept ideas for future Discovery-class missions.

Quick Google search on Dr. Stofan's name found this: What Next for Titan?

Ellen Stofan has a Discovery-class Titan lake lander proposal. I've not seen the presentation, but a friend who has tells me that it is less capable than the ESA lake lander proposed for TSSM. (This would make sense – ESA had a budget of ~$1B for just the lake lander and balloon. Stofan has just $450M and has to fit a carrier craft and launch vehicle into that budget.) The 2007 report did not look at lake landers. I know of Stofan by reputation, and she's highly competent. However, fitting in a carrier, lander (with entry shell), and launch vehicle within a Discovery mission budget seems ambitious. Perhaps this could be done with a New Frontiers budget ($650M with the launch vehicle provided by NASA outside this budget), although the 2007 budget suggested that a budget twice this amount would be needed just for an atmopheric probe.

Aside from above quote's understandable skepticism of the Discovery-class price tag, where would plutonium for this mission come from? I thought it is all already allocated?

[Juramike]

Titan's terrain is pretty varied: If we did pick the land what terrain type would we sample?
The Equatorial bright stuff? the dark dune stuff? the mid-latitude RADAR-bland stuff? or the dark blue ice sand unit (Huygens part II - the taste test), or the Hotei Arcus cryovolcano stuff?

[Now if you could land on just one part of Earth, where would you send it? The white stuff at the poles, the blue stuff, the yellow-brown stuff, or the green stuff?]

Landing in a lake has the advantage of being relatively homogeneous compared to land terrain. (However, I'll contend that it is possible that the different chemical thingys could segregate out vertically into different goopy layers - sampling different depth might give different results). Another advantage of landing in a lake is that the soluble species (and some of the smaller particulates) from surrounding terrain will end up getting washed into the lakes. So in theory, tasting the lake will give you a taste of all the soluble species from all the terrain types that drain into the lake.

In ignorance of the exact instrumentation, the lake lander will have an easier time acquiring the sample, no digging or scooping, just suck through a straw and shoot into the GC (or whatever). Liquids are much easier to handle than solids. Yet other advantage is that the lake lander will drift over time. So you'll get some spatial coverage as well that a lander won't give you.

My favorite mission is still a Titan balloon that has the capability to touchdown and image and sample multiple points along it's path. Then you could hit a lake, a dune, the mid-latitude bland stuff, etc all with one mission...AND get wind and weather information at different varying locations and altitudes.