The First Europa Lander, What can be done first, cheapest & best? Options

[nprev]

I think that many people in this forum would agree that somebody's going to have to land on Europa someday before the rather elaborate schemes to penetrate the outer ice layer will ever fly, if for no other reason than to get some relevant ground truth before committing to such an elaborate, expensive, and risky mission.

EO seems to have ruled out any surface science package for that mission (though it would be nice to change their minds! ), but I think that there is a valid requirement at some point to directly assess the surface properties of Europa in an inexpensive yet creative way. Some candidate instrument payloads might be:

1. A sonar transducer/receiver set embedded within a penetrometer to determine crust density and examine the uniformity of the ice layer within the operational radius of the instrument (looking for cracks and holes, in other words).

2. A conductivity sensor again embedded inside a penetrometer to measure the native salinity of the surrounding material and possibly derive some constraints on the composition of metallic salts in the European crust (saltiness has a major effect on ice properties, in addition to the obvious need to derive the salt content of any underlying ocean).

3. A seismometer for all sorts of reasons.


How does this sound? Any critiques, additions, or subtractions? I omitted a surface imager not only because of bandwidth/extra complexity considerations but also because it seems desirable to penetrate the crust in order to minimize as much as possible reading any contaminants from Io during surface measurements. The orbiter data could be used to sense and subtract this from the penetrometer readings.

[djellison]

I'm sure everyone would love a massive long life rover on the surface of Europa....who wouldn't. Every scientist, every engineer would LOVE to have a rover on Europa.

And we'd all like New Horizons to be a Pluto Orbiter, and DAWN to be sample return, and Messenger to be a lander......

But you have to do what is feasable given time, money, and in this case technology. I would wager that if you put MSL on the surface of Europa - it would be dead with a week due to radiation, MC might be able to comment, but I'd think Mastcam would just get quietly fried. 'Shield it' you might say....that would requrie so much shielding the thing would never get off the pad. (because every kg of shielding requires kg's of fuel for landing, and THAT required multiple kg's of payload capacity )

A comparatively simple impactor / hard lander, perhaps with a decent imager, short life etc...that's currently feasable in a sensible time frame and budget and would tell us a hell of a lot about Europa.

MSL will be ( hopefully ) the 7th succesfull landing on Mars. 4 of those were/will be static landers.

If we were talking out 4th Europan lander..I'd be going 'hell yeah - let's go for wheels' - but for our first effort....one needs to be modest in requirements.

As Alan has said w.r.t. NH.....better is the enemy of good enough.

Doug