Wouldn't one of the biggest challenges be dealing with the high speed of the return capsule for such a mission, aren't we talking about speeds higher than that of the Stardust mission?
The other challenge--really more of a drawback--is that you get essentially zero science return until the sample gets back to Earth. And it is a long mission. So do you fund a mission knowing that you will wait 18 years for ANY data, and that it could fail at any point during those 18 years? There are much less risky missions you could fund.
Fourth, how could SLS change this equation? I am an SLS agnostic. Although I think that HLV is necessary for many human missions, and it _can_ be enabling for some robotic missions, I'm skeptical of the cost in the current political environment. However, SLS might be the only viable way to do sample return at Europa, so I think that this would be worth studying.
What about Curiosity-style spectrometry, mass spec and other instruments for sample analysis?
What I was referring to boils down to this: up until now, nobody has discussed Europa sample return missions. They have discussed Enceladus sample return missions. A-what would be the parameters of a Europa sample return mission?
B-could SLS make any difference for that mission given its difficult parameters (like delta-vee)?
Quote from: Star One on 12/26/2013 09:16 amCould the JUICE mission be reconfigured to if not do sample return then to fly through these plumes & do in situ science on them?Almost certainly not. It's an entirely different mission with entirely different goals. They might be able to shift their observation strategy a bit, but they couldn't really change the main parameters of the mission without it being an entirely different mission--and maybe not workable.
Could the JUICE mission be reconfigured to if not do sample return then to fly through these plumes & do in situ science on them?
There's probably not real reason to go through the plumes. What you'd want is some kind of assessment, particularly looking for organics. Cassini has done that at Saturn with Enceladus.
One thing that just occurred to me is that there might be a benefit to turning JUICE to look at Europa at a point where the plumes might be illuminated by the sun. They might not have considered that yet, and the new data might cause them to reevaluate.
Quote from: ugordan on 12/26/2013 03:16 pmThere ought to be some freedom in tweaking the sub s/c point to move it to higher southern latitudes, but I wonder if flying through the plumes would be considered too hazardous to the solar panels. Even if they wanted to rotate them to present the lowest cross-section to the plume flux, I'd imagine the uncertainty in the actual plume/particle velocities would make predicting the "ram" direction difficult.There's probably not real reason to go through the plumes. What you'd want is some kind of assessment, particularly looking for organics. Cassini has done that at Saturn with Enceladus. But JUICE is only supposed to have a few observations of Europa, so it simply may lack any flexibility to expand the Europa observations without substantially impacting the Ganymede science objectives.
There ought to be some freedom in tweaking the sub s/c point to move it to higher southern latitudes, but I wonder if flying through the plumes would be considered too hazardous to the solar panels. Even if they wanted to rotate them to present the lowest cross-section to the plume flux, I'd imagine the uncertainty in the actual plume/particle velocities would make predicting the "ram" direction difficult.
Quote from: Star One on 12/26/2013 09:16 amCould the JUICE mission be reconfigured to if not do sample return then to fly through these plumes & do in situ science on them? So the U.S. has a lot of Mars scientists, and therefore generates a lot of interest in more Mars missions. There are positives to this and negatives. The positive is that it results in great expertise and focus on a subject. The negative is that it results in slower response to new discoveries, and even neglect of potentially great scientific subjects. For instance, the ice giants remain the last major unexplored objects in our solar system (after New Horizons flies by Pluto), but there is still limited interest in them, meaning that it will probably be 30-40 years before we mount a robotic mission to Uranus or Neptune.
Quote from: mdatb on 12/28/2013 07:53 pm1-I agree. Mars gets a lot of interest and focus due to the many scientists who focus on mars. Thus, we get a lot of information on the subject and focus on putting missions there, but other objects get exploration-starved and projects focusing on them get cut or canceled.2-This comment somewhat helped me understand why we have a 2020 mars rover. 1-But that is not the ONLY reason Mars gets a lot of attention. Mars is a high-value scientific target. There is no way to deny that. Mars is also easily accessible, with regular launch windows and relatively short transit times compared to just about every other target in the solar system. Finally, Mars has always occupied a greater public role than any other planet, a fact that goes back centuries.2-It's not that easy. The Mars 2020 rover was the right decision. The decadal survey prioritized the MAX-C rover mission and the Mars 2020 rover is going to do what MAX-C laid out. That's the way it is supposed to happen. Any other decision would have been in defiance of the wishes of the scientific community. And the only reason that MAX-C came out ahead of a Europa mission was because the Europa mission presented to the decadal survey was both too expensive to recommend, and could not be downscoped by the decadal survey committee itself.
1-I agree. Mars gets a lot of interest and focus due to the many scientists who focus on mars. Thus, we get a lot of information on the subject and focus on putting missions there, but other objects get exploration-starved and projects focusing on them get cut or canceled.2-This comment somewhat helped me understand why we have a 2020 mars rover.
Yes, I was too lazy to check if JUICE will be carrying something similar to Cassini's INMS - which apparently it won't. I agree there's little added value in flying through the plumes in this case.
Quote from: Star One on 12/29/2013 12:34 pmBut now that the Mars rover has been commissioned there should be no further Mars projects initiated when Europa is clearly the next target to be investigated.Where does it say that?
But now that the Mars rover has been commissioned there should be no further Mars projects initiated when Europa is clearly the next target to be investigated.
Sample collection has effectively been agreed for Mars with MSL 2 so let's start looking down the list so to speak.
... then maybe NASA could get started on a Europa mission by 2020 or so. But that should only happen after the overall balance has been restored to the program.
Mars sample return has been a high priority for decades and is only now being implemented.