[ExI] one way ticket to mars

[spike]

>... On Behalf Of Eugen Leitl
...
> 
>>... Anyone wish to refute the notion that any humanned trip to Mars will 
> be one-way?  If you figure out a way to do it, this company would 
> surely be happy to hear from you.  I sure as hell never did figure out 
> a way to get back, and we tried approximately a jillion different
concepts.

>...I would argue that any manned mission would involve sending automation
ahead to build habitat and closed-loop ecosystem, so needs not to be one-way
in principle...

Agreed, and perhaps the 3D printing tech is what we need for that.  If we
get good enough at it, a version of Zubrin's Mars Direct approach might
work.

>...Novel propulsion seems to make travel in 30-40 days feasible...

Disagree.  The only thing we have even vaguely plausible for a non-Hohmann
transfer orbit is fission nuclear, assuming any reasonable extrapolation of
today's tech.  Nuclear is better, but not enough better to give us fast
rides.  I argued 20 years ago that a really good alternative is really not
on our horizon.  That was not popular, but turned out to be right.  It is
farther away today than it was then.  It's chemical rockets for us, and 8
months trip to Mars, any time in the next 50-ish years.  Damn.  {8-[

>... and return is even easier (chemical rocket launch from Mars, and
aerobraking
reentry) so even less need for one-way.
_______________________________________________

I hope you are right.  I am betting on semi-autonomous 3D printers and
assemblers (not nano) building a habitat ahead of the astronauts.

spike