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.

[Cugel]

Why would you go all the way down to the liquid water (if any is present at all)?
All that ice has to come from somewhere and it didn't come falling out of the blue sky.
It's the same ocean that everybody is looking for, just in a frozen state!
Now, the top 1 meter or so might be seriously altered by Jupiter's radiation,
but just 2 or 3 meters down and you're in the ocean.
Melt it, pump it up to the lander and analyse it for organics and other ingredients.
It will probably cost you a billion or 3 but at least it is technically doable.

[JRehling]

Why would you go all the way down to the liquid water (if any is present at all)?
All that ice has to come from somewhere and it didn't come falling out of the blue sky.
It's the same ocean that everybody is looking for, just in a frozen state!
Now, the top 1 meter or so might be seriously altered by Jupiter's radiation,
but just 2 or 3 meters down and you're in the ocean.
Melt it, pump it up to the lander and analyse it for organics and other ingredients.
It will probably cost you a billion or 3 but at least it is technically doable.

Icebergs on Earth also come from the ocean, but I bet they don't contain many squid, clams, or blue whales.

The "3 meter down" lander may have to be the next step, but it will leave a lot to be desired.

[tty]

Icebergs on Earth also come from the ocean, but I bet they don't contain many squid, clams, or blue whales.

Couldn't that possibly be related to the fact that the ocean water has been evaporated (=distilled), then fallen as snow, lain around at subzero temperature in an icecap for thousands of years before finally being calved back into the Ocean?

If you analyzed sea-ice that has actually frozen in/on the ocean you wouldn't have any problems finding organic material and even an occasional small squid frozen into it. Clams are bottom animals and whales sink after death so I wouldn't expect finding them.