I'm back from the Europa Focus Group meeting... Options

[Guest_BruceMoomaw_*]

...which I decided to attend literally at the last possible minute, which is why I didn't alert you guys in advance. Very interesting -- both the discussions about the likely design of the mission (and how to retrieve it from cancellation), and many of the actual science presentations (which aren't on the Web yet, although they probably soon will be). I'll give you some more information tomorrow -- although I can't resist telling Alex that Tom Spilker's subgroup took my ideas about a Europa penetrator, and the printed information I gave them on the subject, seriously enough to recommend making further inquiries to NASA HQ on it. (And without my browbeating them, either. Nyaah.) The case for it, however, is still extremely far from certain.

As I say, more tomorrow.

[Guest_BruceMoomaw_*]

The Europa Ball has little teeny camera ports -- of the sort that could easily be concealed by a crushed outer layer -- and it carries 16 of them to maximize the chances that some will be pointed in the right direction for both close-up and longer range Post-landing photos. (It seems to have no provision for descent photos -- something else, I think, that needs to be changed and easily could be, even given its lack of attitude stabilization.) One could, I suppose, put the camera lenses outside the crushable layer and run optical-fiber lines to them (which do, in fact, run from the camera ports on the current version to a single CCD, with other optical-fiber lines running from the 12 sample cups to a single Raman spectrometer) -- but I'd assume that such O.F. lines would be extremely vulnerable to damage when the layer is crushed.

So the plan, to repeat, is to make the whole thing so rigid and solid-state that it can survive up to 10,000 G -- as with the most sophisticated penetrator designs. (NASA's tests in the late 1970s included repeatedly crashing penetrators even into solid boulders, with a whole variety of scientific instruments onboard, including seismometers 100 times more sensitive than Apollo's -- and the only one that suffered any problems was a CCD camera on the afterbody.)

As for the history of Luna, the JBIS article (Sept. 2000, by Asif Siddiqi et al) is extremely thorough in its sources, and cites both the most recent and detailed Russian accounts and recently declassified US tracking of the Luna probes to confirm that Lunas 5 and 7 didn't brake at all, while Luna 8, during its tumbling final descent, fired its braking engine for only 9 seconds and then in the wrong direction. There's also a lot of detail on the airbags (including Soviet documents grousing about their design problems) -- the Soviets may have kept silent about them at the time to try to make the landings look more like the more sophisticated full-fledged Surveyor soft landings. The article is co-authored by Timothy Varfolomeyev, who's done somc excellent earlier stuff for JBIS in digging up, archaeologist-style, the true space past of his own nation's former secretive tyranny -- including an earlier JBIS article on the first block of Luna missions (1958-60), which I may report on later over in our "Moon" section.