When all the planets are explored in the solar system

Martin Brown wrote:
[Mars Evacs]
The rescue trip would have to fly with 50% more food resources than the
original mission to cater for the crowded return trip.

Does the rescue trip have to be crewed on the way there?

Having said that... if I was going then I'd want to know there was
enough return-trip fuel /before/ I left. If it's manufactured on site
then by the time I get there they've probably manufactured an excess.

I'd also want the space vehicle(s) to have a lot of redundant systems.
I want to get home if things break.

I'm assuming I'm coming home, I'm not settling. I'd take a little more
persuading to settle. Internet access speed totally sucks.

If we're going for some reason other than to say we did, probably
sustainable development is on the agenda - a standing base.

John Schilling wrote:
In article , Sea Wasp says...


There are reasonable ways for them to make
air and water from what's there, as opposed to the Moon, where you
really CAN'T do that unless you happen to be incredibly lucky about
what you bring and where you land. You can make fuel on Mars a lot
more easily than you can make it on the Moon.


s/can/must

Exploring Mars means, your e.g. water reclamation unit has to work or
you die. Exploring the Moon means, your water reclamation unit should
work or you have to go home and come back later.

Only if THAT is the disaster you are postulating. You can't postulate
"undefined disaster", and then specify one that's necessarily worse on
one end than the other. What about "lose 90% of your breathing
supply"? That would be lethal -- and nonrecoverable -- on the Moon,
but on the postulated Mars mission it's just a PITA.




If you assume each one starts with IDENTICAL equipment -- and that
the equipment in both cases is optimized for the Moon -- then hell
yeah, the Mars group is screwed.


Aren't I entitled to assume identical, or at least similar, equipment?

No, because the voyage requirements are different.


Your claim is that exploring Mars is roughly as easy as exploring the
Moon.

Yes and no. My claim is that the two are relatively equally
reachable. More supplies does translate to more COST, but not more
technical difficulty. My other claim is that there's much more
worthwhile to use/get ON Mars than there is on the Moon, such that
it's not really worthwhile to GO to the Moon if your actual intent is
to end up on Mars. I.e., the Moon is NOT a stepping-stone to Mars,
it's a side trip with no real use.


If exploring Mars requires, to ensure safe return, many tons
of expensive, exotic equipment that must work right, whereas the Lunar
case requires a duffle bag full of gear that I can buy at my local
boat & dive shop, then exploring Mars is not as easy as exploring the
Moon.

Fortunate that this is not the case. The "expensive exotic equipment"
is overall less technically demanding to create than most of the
equipment that comes standard in the Shuttle.

MORE stuff, yes. More bizarre, cutting-edge stuff, no. I would
contend that exploring Hawaii is roughly as easy as exploring
Antarctica (assuming, say, 1950s tech but no aircraft), if I'm
starting off from Tierra Del Fuego and have to not resupply on the
way, and only use either what I find when I get there, or what I sent
ahead of me, or what I brought along. Hawaii is much farther away, and
while I can use the same general technology to get there, I'd better
bring a lot more stuff along. And if something goes badly wrong, I
could die in either place. If it's something that I cannot find a
solution for locally, I probably have a better chance of rescue in
Antarctica, if it's not immediately lethal, as the rescue mission will
get there a lot quicker. On the other hand, I'm more likely to find
a solution locally on Hawaii than Antarctica.

(Note that I am *NOT* saying that either of those places is in
actuality equivalent to either the Moon or Mars, both of which are
much more hostile)


Your hypothesis explicitly requires that exploring Mars and the Moon
require similar kinds and ammounts of equipment.

Kinds. Not amounts.


Equal in probability of success, or at least survival, but very *different*
in the ammount of effort required to achieve that probability of success
or survival.

Making the one harder than the other.

Only in certain ways, and not even in all the ways one necessarily
assumes.




The KEY point about BOTH of them is that it is a nontrivial effort to
mount a rescue mission unless (in both cases) you have such a mission
STANDING BY.


What, you're only planning to go to Mars, *once*?

OK, you're a Zubrin fan, so if you go to Mars at all it will only be once,
maybe twice.

Huh? You're making no sense at all here. Zubrin's goal is ongoing
exploration and eventual colonization. Dozens, even hundreds of trips.


But if you're going to stay, there's always going to be a
next mission gearing up, a ship that can be retasked for emergency rescue
at need.

Um, not in the timeframe we're talking about. Or are you going to
contend that we could have gotten another Saturn 5 set up and launched
in 3 days if one of the Apollos had gone funky? They weren't set up
THAT fast.

If your mission is months long, and something goes wrong toward the
END of those months, yeah, probably there's another mission on the
way, or close to on the way. But not on average, until you get to the
"interplanetary travel as routine" stage in which case we're in a very
different kind of situation.


--
Sea Wasp
/^\
;;;
Live Journal: http://www.livejournal.com/users/seawasp/

: Sea Wasp
: My claim is that the two are relatively equally
: reachable. More supplies does translate to more COST, but not more
: technical difficulty.

A longer coast phase *does* translate to more technical difficulty.

: My other claim is that there's much more worthwhile to use/get ON Mars
: than there is on the Moon, such that it's not really worthwhile to GO
: to the Moon if your actual intent is to end up on Mars. I.e., the
: Moon is NOT a stepping-stone to Mars, it's a side trip with no real
: use.

Building infrastructure on the moon (and other near-earth locations)
is worthwhile if your goal is to make regular trips to mars. If you
aren't going to make regular trips, I don't see the "use/get" thing.

Yes, yes, I realize that you contest that infrastrucre on the moon is
worthwhile, because of the 2x(2.5km/s) delta-v required to reach it,
among other issues. But for a sizeable extra-atmosphere presense, it beats
the alternatives, naict.


Wayne Throop http://sheol.org/throopw

Wayne Throop wrote:

Yes, yes, I realize that you contest that infrastrucre on the moon is
worthwhile, because of the 2x(2.5km/s) delta-v required to reach it,
among other issues. But for a sizeable extra-atmosphere presense, it beats
the alternatives, naict.

Well, since you'll have to be building everything on the Moon
completely sealed, completely self contained, etc., barring a
discovery of some hidden water stash or something, what's the real
advantage of building it on the Moon rather than in orbit, where it's
NOT at the bottom of that gravity well?

If you've got something on the moon that we actually want, then yeah,
there's excellent reason to go there. But if you just want it as a
landing pad, is it really worth it to have a landing pad with a
noticeable gravity well?




--
Sea Wasp
/^\
;;;
Live Journal: http://www.livejournal.com/users/seawasp/

: Sea Wasp
: Well, since you'll have to be building everything on the Moon
: completely sealed, completely self contained, etc., barring a
: discovery of some hidden water stash or something, what's the real
: advantage of building it on the Moon rather than in orbit, where it's
: NOT at the bottom of that gravity well?

Mass to hide under wrt solar flares etc, and to supply some of the heavy
bits to construction projects.

However, yes, if it were me, I wouldn't go to either the moon or mars as
a *goal* in the near term, except insofar as the moon might have things
you could catapult to construction projects elsewhere instead of lugging
from earth. But that's just me.

What does mars, or the moon, have that you can't get on earth easier?

And as to going to mars or beyond, if you have a habitat that's been
run for years stably, and you've proven it self-sufficient, lofting it
on an orbit to most anywhere becomes much less risky.


Wayne Throop http://sheol.org/throopw

Sea Wasp wrote:

Martin Brown wrote:

Sea Wasp wrote:

John Schilling wrote:


Your argument might as well be that wintering over at the South Pole is
as easy a trip as a weekend in the local state park, for a Boy Scout
troop. Because, see, only incompetents would make the trip without
adequate training and equipment, therefore the Boy Scouts will have
right training and equipment whether they're going to the state park
or Antarctica, therefore it's just as safe and easy either way.

Not really. It does depend on the assumptions you make, true, but
you exaggerate a number of issues. Mars offers opportunities to
support your marooned astronauts, assuming they brought the right
equipment,

Which includes a fully robotic hospital to care for the invalid humans
whilst they re-adjust to Mars gravity after 300 days weightless.

No, actually. They spend most of the trip in Mars gravity. Read The
Case For Mars.

Great science fiction and wildly optimistic. You have to admire Zubrin
but you do not have to swallow his Mars tale hook line and sinker...

Regards,
Martin Brown

Martin Brown wrote:

Great science fiction and wildly optimistic. You have to admire Zubrin
but you do not have to swallow his Mars tale hook line and sinker...

Can you point me to a cogent critique, then? There are two points I
recall thinking him overly optimistic on, but those weren't really
central to his argument.




--
Sea Wasp
/^\
;;;
Live Journal: http://www.livejournal.com/users/seawasp/

:: What does mars, or the moon, have that you can't get on earth easier?

: "
: Land. According to reputable authorities, it isn't being made around
: here any more. (Give or take sea reclamation projects. I think the
: Star Trek movie novelisation established they drained the
: Mediterranean.)
:
: However, it mostly can be bought more cheaply than a space rocket. And
: there isn't much terrific farming land elsewhere in the solar system.

Right; don't compare prices for land in manhattan, or even prime
farming land. Compare prices for land in the gobi desert, or antarctica,
or death valley, or subsea habs, or whatever.

The notion that you can obtain land by terraforming mars much more easily
than you can by terraforming the moon is fine... but it's much easier
to terraform earth.

One might say, "a second basket to put some of the species' eggs in".
But that's so long term, it's much like "we should stop burning fossil
fuels". Plus, what has the species done for me *lately*? Sure, yeah,
we should. But eh, shrug. (Mind you, the "eh, shrug" is not how *I*
feel about these issues; it's how they are going to be treated by most.)

I used to think that I was cool, driving around on fossil fuel.
Then I found what I was doin' was driving down the road to ruin.

--- James Taylor (no longer as persuasive as in the 70s,
but still a nifty lyric IMO)


Wayne Throop http://sheol.org/throopw

"Wayne Throop" wrote in message
...
:: What does mars, or the moon, have that you can't get on earth easier?

: "
: Land. According to reputable authorities, it isn't being made around
: here any more. (Give or take sea reclamation projects. I think the
: Star Trek movie novelisation established they drained the
: Mediterranean.)
:
: However, it mostly can be bought more cheaply than a space rocket. And
: there isn't much terrific farming land elsewhere in the solar system.

Right; don't compare prices for land in manhattan, or even prime
farming land. Compare prices for land in the gobi desert, or antarctica,
or death valley, or subsea habs, or whatever.

The notion that you can obtain land by terraforming mars much more easily
than you can by terraforming the moon is fine... but it's much easier
to terraform earth.

One might say, "a second basket to put some of the species' eggs in".
But that's so long term, it's much like "we should stop burning fossil
fuels". Plus, what has the species done for me *lately*? Sure, yeah,
we should. But eh, shrug. (Mind you, the "eh, shrug" is not how *I*
feel about these issues; it's how they are going to be treated by most.)


the thing is, what happens when the earth and moon are used? for them to
drain the Med, that is pretty severe, even in the 24th century a la Picard
they were trying to raise a continent. Land was on a premium on earth in
star trek.

In message , Sea Wasp
writes
John Schilling wrote:
In article , Sea Wasp says...


There are reasonable ways for them to make
air and water from what's there, as opposed to the Moon, where you
really CAN'T do that unless you happen to be incredibly lucky about
what you bring and where you land. You can make fuel on Mars a lot
more easily than you can make it on the Moon.
s/can/must
Exploring Mars means, your e.g. water reclamation unit has to work
or
you die. Exploring the Moon means, your water reclamation unit should
work or you have to go home and come back later.

Only if THAT is the disaster you are postulating. You can't
postulate "undefined disaster", and then specify one that's necessarily
worse on one end than the other. What about "lose 90% of your breathing
supply"? That would be lethal -- and nonrecoverable -- on the Moon, but
on the postulated Mars mission it's just a PITA.

Once again, why? It's a highly unlikely accident, but in neither case
will the crew have a complete reserve for a long stay.
The most likely accident is that something fails in your rocket (which
was always a concern with Apollo. The CM pilot knew he might have to
come back alone). On the moon _if you have the rescue ship_ which is not
guaranteed with current plans or funding, you just sit tight for the
time it takes to reach you - a few days plus time to prepare the ship.