
A daring lander for Jupiter’s icy moon - lisper
http://arstechnica.com/science/2015/11/attempt-no-landing-there-yeah-right-were-going-to-europa/
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ant6n
"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.

~~~
mapt
...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.

~~~
ant6n
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.

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iwwr
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.

~~~
simonh
> This crucially depends on a 70ton (LEO) launcher and it's no guarantee SLS
> will get off the ground.

That's a fair point of course, but equally there's no point building the
rocket if we don't also plan for things for it to launch.

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mapt
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.

~~~
simonh
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.

~~~
mapt
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.

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hackuser
Representative John Culberson's district is in Houston. Does anyone know if it
includes many NASA facilities or people in the space industry?

~~~
adventured
No it does not.

From the article:

"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."

