"Jupiter showers its moon Europa with enough radiation to kill a human in just a few days."
Of course you'll freeze in a matter of minutes. Or suffocate in a matter of seconds. Also, there's like nothing to eat.
Point is, probably the only place where you could built a viable habitation unit is below the ice anyway, where radiation is a bit less of a concern. And in any case, in space you have to protect against so many things that radiation may not add a lot of marginal complexity.
...Or it might be completely prohibitive, depending on what sort of radiation is present. High fluxes of low energy radiation are much easier to shield against than low fluxes of high energy radiation. This is incidentally why there is at present no realistic plan to deal with GCR's in interplanetary travel.
Getting beneath Europa is a perfectly workable plan only if you assume that you can get to the Europan surface safely. It may be that just approaching it for landing gives too much dose for short-term survival.
Absent good reason, though, Europa makes little sense for a manned mission relative to Ganymede or Callisto, which likely also have oceans, or Titan, which has an atmosphere to boot.
Fair enough. It's just that 'kills you in days'-phrasing that sounds strangely ...not urgent, given the context of all the other things that'll kill you right away.
>Of course you'll freeze in a matter of minutes. Or suffocate in a matter of seconds. Also, there's like nothing to eat.
The surface does have organic matter, together with rock mixed in with the ice, so there is potential for in-situ resource utilization to support human habitation.
This crucially depends on a 70ton (LEO) launcher and it's no guarantee SLS will get off the ground. It's also uncertain if private actors manage to put together reliable heavy launchers, even by 2020-2025.
This is also only a lander and not a rover, but any lander will be valuable, mobile or not. Obviously, Europa has only 35% of Mars' gravity, so a wheeled rover may not even work in those conditions, including the rugged and difficult surface to traverse.
The best would be an underwater robot on a tether. But then you have to get through the ice. I believe there was once a proposal to melt through the ice using some sort of fission device, but these days people don't like nucolar things.
Why not one class of small NEP orbiter-surveyor for every outer system moon, and fly ten or twenty missions of this class, before we bother thinking about landers?
There's only so much data you can gather in flybys.
I don't think NASA has the budget to launch 23+ orbiter missions, regardless of how cheap and generic the orbiters are. Anyway, I think if you're going to spend a large fraction of a Billion dollars just getting there, it makes sense to spend a bit more to make sure the payload is optimised for the job. Each one of these missions has a good chance of being the only one of it's kind for one or more generations. Better to do it right the first time.
We are entering an era of cheap launch costs. Duplication of a design costs near-zero, all the price is in the fabrication capacity, the design, the testing, the engineering, keeping a subject-matter-expert control team on standby to make executive decisions for a few hours a month, and the remaining launch costs.
In practice, the Space Shuttle Transportation System, fully ammortized, cost about $1.5B per launch to loft 15 tons to low orbit in practice.
Falcon Heavy will launch about 40 tons for ~$100M, a factor of 40 improvement. The Russian launch vehicle Proton-M was already at about 20 tons for ~$100M, and Atlas V 552 about 20 tons for ~$200M.
"Politics ultimately called, and he ended up taking a Congressional seat that covers much of the affluent western suburbs of Houston. His district doesn’t include Johnson Space Center, but as a member of the House Appropriations Committee, its leaders there look to him for support. Yet they sometimes grumble that the Houston House member seems more interested in JPL than his hometown space center."
Of course you'll freeze in a matter of minutes. Or suffocate in a matter of seconds. Also, there's like nothing to eat.
Point is, probably the only place where you could built a viable habitation unit is below the ice anyway, where radiation is a bit less of a concern. And in any case, in space you have to protect against so many things that radiation may not add a lot of marginal complexity.