Is Europa really the "highest priority" of the community?, Cleave said it was at LPSC? Options

[mcaplinger]

From Emily's LPSC blog: "Bob Pappalardo would not sit down until he got Cleave to acknowledge that Europa is the consensus highest priority of the planetary science community."

Cleave was obviously poorly prepared for this session, but I don't see that this acknowledgement is either meaningful or particularly accurate. If Europa were the "highest priority" of the PS community as a whole, then one might wonder why we were spending all this money on Mars. I could easily imagine that Europa is the highest priority of the outer planets community, but frankly I was surprised when Europa Orbiter appeared in the '07 budget (presumably the result of some serious lobbying on someone's part.) It was pretty obvious to me then that there would be no money for it, especially in the aftermath of JPL running the old EO project into the ground with cost overruns and engineering upscopes. (And JIMO is best forgotten.)

Don't get me wrong, I would love to be involved with a Europa mission (we did what I think was a good proposal design for EO) but I don't see either the money or the political support being there in the near term. I know it's frustrating, but one has to be realistic, and it might help to avoid the aura of entitlement that I perceive is building in some parts of the community (not referring to you, Bob). Of course, I am just a lowly engineer.

[Guest_BruceMoomaw_*]

Regarding other ideas: two of the second-tier NF missions proposed by the Decadal Survey were an Io Observer (a Jupiter orbiter to make repeated Io flybys), and a Ganymede Observer (ditto for that world). It doesn't take much imagination to envision using one copy of the same type of craft -- with few design changes -- for all four Galileans, for a lower-cost and higher-data replay of Galileo. The main problem might be that you very much want an Io Observer to have a polar rather than equatorial orbit to minimize its radiation dose, which minimizes your ability to do a gravity-assist tour of the other moons.

As for Titan: the cheaper version of the Titan Organics Explorer -- the wind-blown hot-air balloon that would make repeated landings to sample the surface -- was projected at the COMPLEX meeting to cost about a billion dollars (although this would probably turn out to be about as accurate as NASA's other cost estimates). It would have kept itself within that cost limit largely by simply skipping any accompanying Titan orbiter, and communicating directly with Earth instead. If so, then -- IF Cassini can locate a spot on Titan that seems likely to have water volcanism, and thus water-processed organics -- it might be possible, within the NF budget, to drop off a stationary lander onto that one spot, do the same analyses planned for TOE, and have it radio its data directly to Earth.

Alternatively, it might be possible within the NF budget to drop off, by itself, a wind-blown balloon that would never land, but would just blow around Titan mapping its surface in far more detail than any orbiter can do. (While the spectral windows for sunlight piercing Titan's atmosphere would seriously limit the ability of such a low-altitude permanent balloon to map the surface composition of Titan itself with near-IR, could it use a cluster of small lasers at different frequencies to illuminate the surface and allow such a near-IR spectrometer on the balloon to look for especially interesting spectral lines?)

All this, to put it mildly, is uncertain within the NF budget; but then we ARE just trolling for possibilities right now. And NASA has already announced that it will include as many as 6-10 overall Solar System mission concepts within its next New Frontiers AO in 2008.