Bush Space Plan - unwise?

John Glenn said that Bush's space plan "pulls the rug out from under our scientists" and might fail to put astronauts on Mars.

http://www.cygo.com/

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> From: cygonaut [mailto:george@...]
> John Glenn said that Bush's space plan "pulls the rug out
> from under our scientists" and might fail to put astronauts on Mars.
> http://www.cygo.com/

Two clicks later and I hit a dead end. At no point am I told what is actually going to be cancelled. What I am told is, "Plan X is bad! Don't support plan X!"

Personally I'd prefer to be told what Plan X is and why I shouldn't support it than be lectured by a politician. Firstly it makes me think Glenn probably doesn't understand what he's saying. Then I think that Glenn's doing this just so the Kerry camp can bash what's possibly the one good (or least bad) thing the Bush camp has managed to do. Finally it makes me believe that both NASA & Glenn think I'm too stupid to understand the issues and need it spoonfeed to me in ver-ry sim-ple terms con-tain-ing less than one syl-i-ble.

True or not, that's my gut reaction. And I *support* spending money on space. God I hate politics...

By the by, anyone know what Glenn was talking about specifically?

ANTIcarrot.

>By the by, anyone know what Glenn was talking about specifically?

De-funding some of Hubble's and ISS's future plans, and cancelling plans for
robotic missions not yet launched, in order to be able to fund lunar and
Mars missions without increasing NASA's budget much.

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Here's my take on Glenn's criticism of Bush's space plan:

1. -- For a few bucks we can do science that was planned before and
has absolutely nothing to do with Bush's moon-Mars plan.. and what
the heck's wrong with that by the way?
2. -- The moon is a waste of money. If you you want to go to Mars
just GO dammit!

Here's Mars Society's interpretation of Glenn's criticism of Bush's
space plan:

John Glenn Calls for "Direct to Mars" Plan
March 5, 2004
For further information about the Mars Society, visit our website at
www.marssociety.org.

In a speech delivered at Cape Canaveral, former astronaut and US
Senator from Ohio John Glenn called for designing the new space
initiative around "the direct to Mars" plan.

John Glenn's comments were repoerted in Reuters wire story by Broward
Liston, part of which is reproduced below.

>From Reuters:

Glenn said he would support returning to the moon for research
purposes, but urged the panel to seriously consider whether building
habitable moon bases as a stepping stone to Mars was cost effective.

"In effect you're making a Cape Canaveral out on the moon. It would
be a smaller one, I'm sure, but it would be enormously complex,"
Glenn said. "It just seems to me the direct-to-Mars (route) is the
way to go."

He warned NASA might "use up all our money on the moon and never get
to Mars." One commission member, Neil de Grasse Tyson, an
astrophysicist and director of the Hayden Planetarium in New York,
called Glenn's testimony "refreshing in its candor."

**** **** ****

Glenn's comments about the need to avoid a massive Lunar diversion
are right on the mark. From the engineering point of view, the idea
of launching Marsbound spacecraft from the Moon is utter nonsense.
The reason why this is so is because rocket propulsion requirements
to go from Low Earth Orbit (LEO) to the Moon and land are a delta V
of 6 km/s, while it only requires 4.5 km/s of delta-V to go from LEO
to Mars and land. So EVEN IF THE LUNAR CAPE CANAVERAL WERE ALREADY
BUILT, and large supplies of rocket fuel were available right now,
sitting in tanks on the lunar surface, and available FOR FREE, it
would still make no sense for a Marsbound spacecraft to go to the
Moon and refuel, as it would take more propellant in LEO to go to the
Moon than it would to go straight to Mars.

The "Lunar Cape Canaveral" is thus really a LUNAR TOLLBOOTH, which
will cost decades of time and tens of billions of dollars to
construct, and whose use, forced as a bureacratic imposition on Mars
mission planners, would at least double the cost of Mars missions,
assuming that any budget were available for Mars missions after the
logistic burden costs required to support the Lunar Tollbooth itself
are paid for.

If you want to go to Mars, you need to go to Mars.

An extensive disccusion on Mars mission designs that can actually
achieve the goal of human Mars exploration will be held at the 7th
International Mars Society Convention, Palmer House Hilton, Chicago,
August 19-22, 2004. Registration is now open at www.marssociety.org.

For further information about the Mars Society, visit our website at
www.marssociety.org, or contact info@m....

> From: George Perkins [mailto:george@...]

> 2. -- The moon is a waste of money. If you you want to go to Mars
> just GO dammit!

The problem is that Mars is a complete waste of time once the issue of life has been resolved, and an even bigger waste of time if it isn't resolved quickly. Really. It is. There's absolutely nothing else to do there aside from finding life, and planting flags and foot-prints. For the next hundred years at least...

The moon is potentially useful for He3 and general building material. Both missions also give us the vehicles and experience to go to the asteroids, which are also a source of scientific curiosity and potential monetary value. Intended or not, that could be the true value of Bush's space plan. It would give us the vehicles and experience to go to other places very easily and within a reasonable budget, since NASA would be using completely off the shelf equipment. Of course we've been there before with the Saturn 5. :(

And, erm, quite frankly if (and it's a big if) it was done properly, it might be worth the loss of the Hubble and science time on the ISS. A Luna base could well include a 4m 'hubble'. I am however well aware of the problems of putting all your eggs in one basket. Besides which the Hubble should be saved anyway as a piece of global heritage.

Glenn says:
> "In effect you're making a Cape Canaveral out on the moon. It would
> be a smaller one, I'm sure, but it would be enormously complex,"
> Glenn said. "It just seems to me the direct-to-Mars (route) is the
> way to go."

It's very likely that using the Moon 'as a stepping stone' translates more accurately to 'as a proving ground' rather than 'as a petrol station'. Unless Glenn has seen Bush's detailed plans (and he's a lucky sod if he has - 'cause no one else seems to) then his statement is either naivety, the onset of senility, or just so much political BS.

> He warned NASA might "use up all our money on the moon and never get
> to Mars."

Quite true. But better wasting money going somewhere & writing history than going round in circles on the station. Sometimes you learn more actually doing something than you do practising for it.

Mars Direct says:
> Glenn's comments about the need to avoid a massive Lunar diversion

> Moon than it would to go straight to Mars.

The Mars Society *really* should know better. Of course it's perfectly in line with their own agenda to use rubber science to publicly discourage anything that would postpone or jeopardise a mars landing. And to suck up to the potential new administration, who seems to be organising this particular NASA/Bush bash.

> The "Lunar Cape Canaveral" is thus really a LUNAR TOLLBOOTH,

More of a Luna red herring I suspect.

ANTIcarrot.

Public support is not that great either. This would color
Congressional budgetary consideration.

The New York Times/CBS News poll conducted January 12-15 revealed
that 40 percent of the public believes that the US is spending too
much on space exploration programs, the highest fraction from four
such polls dating back to October 1998. The poll also showed that 48
percent of the public favors, but 47 percent oppose, a human mission
to Mars, a result similar to a recent AP poll. Fifty-eight percent
of the public were also opposed to a permanent base on the Moon,
with 35 percent in favor.

http://www.spacetoday.net/Summary/2143

That's part of why I predicted immediately that the Shrub plan wasn't
going to fly; people weren't introduced to it in a fashion that lets
them appreciate it properly.
I try to educate people about things as often as I run into negative
sentiments about space:
During the height of Apollo spending, space never got more than 3 to
5% of the budget, and now it's a small fraction of 1%. We actually do
spend more on junk food, alcohol, cosmetics, pets, illegal drugs,
lotteries and many more things (each thing, individually) than we
spend on the space program.

I'll have to look up the articles and figures, but I believe that
1996 (ish) was the first year that industries making use of the
unique space environment produced enough economic profits that it was
greater than the total expense by all global space efforts that year
(telecommunications and such zero-mass efforts simply using the space
environment as a medium of traffic).

And a more complicated side issue -which should appeal to this list-
is that an ultimate (though actually rather near-term goal) is to
make the space effort economically self-suficient through conducting
much of the activity in space, using space resources. If we can
engender a savings -for instance by producing water and fuels from
NEA materials, then we effectively make a profit. Everything we
launch to LEO which is bound for GEO or interplanetary space is ~45%
by IMLEO the oxidiser in the upper stage for sending it beyond LEO.

Strategic metals from NEAs is also a not-too-far-out longer term
way, with SPS power and eventual space industries replacement of
heavy polluting industries on the ground being the longer term goals.
The end-goal of removing polluting industries from the biopsphere is
the ultimate -not to mention mitigating the risk of planetary
impactors (NEAs are the key).
Eventually, space industries can make profits from goods and
services to drive the civilization's economies to such immense scales
to absolutely dwarf what we today are accustomed to think of as
global economic scale (Read John S. Lewis).

George Perkins wrote:

Sorry for being almost a week behind on this - I've been incommunicado.

Message: 2
Date: Fri, 05 Mar 2004 21:44:10 -0000
From: "George Perkins"
Subject: Re: Bush Space Plan Unwise?

[SNIP]

> Here's Mars Society's interpretation of Glenn's criticism of Bush's
> space plan:

> John Glenn Calls for "Direct to Mars" Plan
> March 5, 2004
> For further information about the Mars Society, visit our website at >
www.marssociety.org.

> In a speech delivered at Cape Canaveral, former astronaut and US
> Senator from Ohio John Glenn called for designing the new space
> initiative around "the direct to Mars" plan.

> John Glenn's comments were repoerted [sic] in Reuters wire story by
> Broward Liston, part of which is reproduced below.

> From Reuters:

> Glenn said he would support returning to the moon for research
> purposes, but urged the panel to seriously consider whether building
> habitable moon bases as a stepping stone to Mars was cost effective.

> "In effect you're making a Cape Canaveral out on the moon. It would
> be a smaller one, I'm sure, but it would be enormously complex,"
> Glenn said. "It just seems to me the direct-to-Mars (route) is the
> way to go."

> He warned NASA might "use up all our money on the moon and never get
> to Mars." One commission member, Neil de Grasse Tyson, an
> astrophysicist and director of the Hayden Planetarium in New York,
> called Glenn's testimony "refreshing in its candor."

> **** **** ****

> Glenn's comments about the need to avoid a massive Lunar diversion
> are right on the mark.

This is exactly the position you would expect Bob Zubrins pet martians
to take; Zubrin's books - and his scholarship and positions as advocated
in them - have, in this group, been criticized as intellectually
dishonest. His major fault seems to be the very human and
understandable failing of letting his desires dictate his beliefs; in
his eagerness to get a human footprint on Mars, he is willing to
dispense with anything which would seem to be a delay - even if that
means discarding prudence (establishing a permanent space-based
infrastructure) or intellectual honesty (the giant mirrors for an SPS
being utterly impossible in his estimation - but being part of his
design for martian terraforming). First and foremost, Zubrin (and, by
extension his Mars Society) is an ADVOCATE; he is trying to PUSH an idea
- it is a pursuit more akin to evangelism than to scholarly debate.
Data not favorable to his position is never mentioned - or sometimes
distorted.

> From the engineering point of view, the idea of launching Marsbound
> spacecraft from the Moon is utter nonsense. The reason why this is so
> is because rocket propulsion requirements to go from Low Earth Orbit
> (LEO) to the Moon and land are a delta V of 6 km/s, while it only
> requires 4.5 km/s of delta-V to go from LEO to Mars and land. So EVEN
> IF THE LUNAR CAPE CANAVERAL WERE ALREADY BUILT, and large supplies of
> rocket fuel were available right now, sitting in tanks on the lunar
> surface, and available FOR FREE, it would still make no sense for a
> Marsbound spacecraft to go to the Moon and refuel, as it would take
> more propellant in LEO to go to the Moon than it would to go straight
> to Mars.

Okay, here's an example of a distortion. These numbers seem familiar...
Ah, yes - here it is on page 98 in my copy of Zubrin's "Entering Space",
almost word for word. Trouble is, are these numbers accurate? For
reference, let me point you to
http://www.pma.caltech.edu/~chirata/deltav.html , which I found on my
first Google search for '"Delta V" Mars Moon'. I am sure other sources
are available. First, note the 'Apples to Oranges' comparison the
Delta-V for trips to and from each of the destinations are given FROM
LEO, as if all Mars bound craft launched from the moon would have to
burn 3.2 km/s to reach LEO before beginning its journey to mars! Zubrin
could have chosen to use the C3=0 earth orbit as the basis for his
comparison, but it would not have served his goal. The diagram on the
web page I have pointed you to is very helpful - and reveals this
fallacy in a very intuitive way. Doing the numbers, do they add up?
Well, from LEO to GTO to C3=0 to Lunar Orbit to Lunar surface is 2.5 +
0.7 + 0.7 + 1.6 = 5.5km/s; close enough that we can give Bob the benefit
of the doubt. And the trip from LEO to GTO to C3=0 to Mars Low Energy
Transfer Orbit to Mars C3=0 and beyond works out as 2.5 + 0.7 + 0.6 3.8km/s but note that this requires the use of aerobraking, making your
trip much slower or much deadlier - and one way. But what about leaving
from the moon? Let's see - Lunar Surface, to Lunar Orbit, to Earths
C3=0, to a similar Mars Low Energy Transfer Orbit is 1.6 + 0.7 + 0.6 2.9km/s.

> The "Lunar Cape Canaveral" is thus really a LUNAR TOLLBOOTH, which
> will cost decades of time and tens of billions of dollars to
> construct, and whose use, forced as a bureacratic [sic] imposition on
> Mars mission planners, would at least double the cost of Mars
> missions, assuming that any budget were available for Mars missions
> after the logistic burden costs required to support the Lunar
> Tollbooth itself are paid for.

I think here it is the "... decades of time ..." that Zubrin (and his
Mars Society) really hates; don't bother doing it right, just do it NOW.

> If you want to go to Mars, you need to go to Mars.

> An extensive disccusion [sic] on Mars mission designs that can
> actually achieve the goal of human Mars exploration will be held at
> the 7th International Mars Society Convention, Palmer House Hilton,
> Chicago, August 19-22, 2004. Registration is now open at
> www.marssociety.org.

> For further information about the Mars Society, visit our website at
> www.marssociety.org, or contact info@m....

Don't get me wrong, I like Bob Zubrin a lot - he has thought outside the
box on behalf of space at least once, and as an advocate for science
education and getting folks lined up behind a "Humanity Amongst the
Stars" vision, he's pretty good. But don't let him fool you - he can
blarney with the best of them, and his positions are carefully
constructed to support the irrational belief that everything in space
must be, always and only, Mars.

It is unfortunate that Bush spoke in terms of building spacecraft on the
surface of the moon (a very distant prospect) and refueling them on the
surface. He just got some bad advice there. A far more sensible plan
is recovery of lunar oxygen (and maybe hydrogen too if the polar ices
can be mined economically) and then its delivery by tanker to the L-1
point. Then, a space ship bound for Mars (or any other points beyond)
can rendezvous with the tanker at L-1, refuel, and then slip back off
the L-point towards Earth. If the craft then whips around the Earth
while burning most of the fuel near the lowest point of the gravity
well, it will gain a significant potential-to-kinetic energy boost in
the process.

This is a scenario the Mars-first crowd will never address, because,
unlike refueling on the lunar surface, it makes good sense.

Regards,

Mike Combs

Was Bush that specific about it? I thought it was more a vague
statement about using the resources of the Moon - which is clearly the
right way to go, whether in your scenario or another (other lunar
orbits may make more sense than L1 for rendezvous). You're right - I've
never understood why Zubrin and others (even John Lewis) insist, in
their comparisons, on landing their entire interplanetary craft on the
Moon and then taking off from there again, obviously that's a waste.
The real question is how we take those steps that make use of lunar
resources happen...

Arthur

On Mar 12, 2004, at 9:31 AM, Combs, Mike wrote:

Last time I talked with Bob he considered using the
moon at all a waste of time and not necessary. Though
since then he has gone back from that viewpoint and is
embracing the Bush plan for the Moon to Mars.

As for the refuleing, I agree. I think of it alot
like flying a fighter jet long distance, you never
land to refuel, just do it on course. I belive that
the moon is a very viable resource for oxygen.
However, I am not holding my breath on economically
ways to mine hydrogen, at this time I see it only as a
potential.

I'd be very interested to see if we could find a nice
dormant comet with H2O that we could take advantage
of, or some kind of carbanoceous chondrite with some
hydrogen on it. This is my biggest criticism of
Bush's plan, no mention of NEO exploitation.

Ryan Z

--- "Arthur P. Smith" wrote:

From: Arthur P. Smith [mailto:apsmith@...]

> Was Bush that specific about it? I thought it was more a vague
> statement about using the resources of the Moon -

He didn't spend a lot of words on the subject, but did say that we might
save expense by building space craft on, and launching them from, the
moon.

> which is clearly the
> right way to go, whether in your scenario or another (other lunar
> orbits may make more sense than L1 for rendezvous).

What orbits were you thinking about?

> You're right - I've
> never understood why Zubrin and others (even John Lewis) insist, in
> their comparisons, on landing their entire interplanetary craft on the

> Moon and then taking off from there again, obviously that's a waste.

I think it's because of all the gas stations we've pulled into in our
lifetime, every single one of them was built on the ground. None of
them were built up in the clouds floating around. There's just a
conceptual bias that in order to build a refueling station (or a
telescope, or a manufacturing facility), we first have to find a plot of
land to build it on. It's a bias so ubiquitous that most don't even
recognize it as a bias.

Regards,

Mike Combs

> From: Ryan Z [mailto:ryjaz@...]

> I'd be very interested to see if we could find a nice
> dormant comet with H2O that we could take advantage
> of, or some kind of carbanoceous chondrite with some
> hydrogen on it. This is my biggest criticism of
> Bush's plan, no mention of NEO exploitation.

Unfortunately many people see a mars landing as science fiction. Say 'asteroid mining' to them and really wouldn't understand what you're talking about. If the same basic hardware can go to the moon and mars there's no reason it couldn't be sent to a small NEO rock. since at that point the hardware is designed and thoroughly flight tested, it would be cheap.

IF - and it's a big capital if - there is political will for it. Last time we didn't. In twenty years time, who can tell? Hopefully by then commercial space flight will mean more than TV & comm satellites.

ANTIcarrot.

On Mar 12, 2004, at 11:33 AM, Combs, Mike wrote:
>
>> which is clearly the
>> right way to go, whether in your scenario or another (other lunar
>> orbits may make more sense than L1 for rendezvous).
>
> What orbits were you thinking about?

Depends how long the craft is waiting there for fueling/refueling. If
it's days, a low orbit like those used for the Apollo rendezvous makes
some sense; longer waits I would think a somewhat higher orbit, but not
necessarily as far as L1. My reasoning here is that the refueling
vehicle would presumably be reusable also and need extra fuel and time
to get to and from the higher orbits - though really this is somewhat
off the top of my head here :-)

Arthur

From: Arthur P. Smith [mailto:apsmith@...]

> On Mar 12, 2004, at 11:33 AM, Combs, Mike wrote:
> >
> > What orbits were you thinking about?
>
> Depends how long the craft is waiting there for fueling/refueling. If
> it's days, a low orbit like those used for the Apollo rendezvous makes

> some sense; longer waits I would think a somewhat higher orbit, but
not
> necessarily as far as L1.

The logic of the whip-around maneuver is that you're taking fuel which
has lots of potential energy, due to having been pushed "uphill", and
converting much of it to kinetic energy at that burn at the lowest
practical point in the gravity well. So L-1 is favored since that's a
point of relatively high potential energy in the Earth-moon system.
There are other Lagrange points with higher potential energy, but an
advantage of L-1 is that it's relatively easy to slip off the point and
swing back down toward the Earth. Easy as falling off the proverbial
log!

I've had others point out to me that the Earth-Sun L-1 point is a region
of even higher potential energy. But since travel to Earth-moon L-1
would be a matter of a couple of days, while travel to Earth-sun L-1
would be on the order of a couple of weeks, I'd consider the Earth-moon
L-1 point to be a more likely departure point for expeditions leaving
Earth.

> My reasoning here is that the refueling
> vehicle would presumably be reusable also and need extra fuel and time

> to get to and from the higher orbits - though really this is somewhat
> off the top of my head here :-)

I'd agree that we should expect the tanker to be a reusable vehicle, but
I'm envisioning the tanker shuttling between the surface of the moon and
the rendezvous point. In which case the higher Earth orbits are easier
to reach from the moon than the lower ones. One has to find a trade-off
between a point not too difficult to reach from Earth, nor too difficult
to reach from the moon either, since a substantial mass of fuel is
involved. L-1 strikes me as a good compromise.

Regards,

Mike Combs

--- "Combs, Mike" wrote:
> I'd agree that we should expect the tanker to be a
> reusable vehicle, but
> I'm envisioning the tanker shuttling between the
> surface of the moon and
> the rendezvous point.

Why use a tanker and not a stationary space station?
You could then use a mass driver to shoot the fuel to
the base. This owuld also have the side benefit of
gathering a lot of raw materials (used as containers
for the O and H) for structural expansion of such a
base.

Another option if going along with the base is to just
shoot regolith to a station and then do all processing
in the station to seperate out the fuel.

Ryan Z

Goodness,

Why use devices that consume so much energy when we have technologies
available that will perform these actions without using some much as a
volt not a drop of propellant?

How about using an automated IGV? An IGV is a "flying saucer" that
basically uses the Searl effect to create an inverse gravity field. Yes,
such a device was created by man, hang on, in 1946...

We need to think a bit more outside of the box people, if we have the
technology to make it worthwhile for stores to open in space (it costs
1/2 billion dollars to place the shuttle in orbit) then we also need to
discuss how to do this cheaply.

1/2 billion dollars for about 2 tons of cargo makes for a very expensive
box of kleenex... What, a box of kleenex is light? True, but you also
have a 3-dimensional space limit...

My 2 cents

Karell Ste-Marie
C.I.O. - BrainBank Inc.

From: Ryan Z [mailto:ryjaz@...]
Sent: Friday, March 12, 2004 5:14 PM
To: spacesettlers@yahoogroups.com
Subject: RE: [spacesettlers] RE: Bush Space Plan Unwise?

--- "Combs, Mike" wrote:
> I'd agree that we should expect the tanker to be a
> reusable vehicle, but
> I'm envisioning the tanker shuttling between the
> surface of the moon and
> the rendezvous point.

Why use a tanker and not a stationary space station?
You could then use a mass driver to shoot the fuel to
the base. This owuld also have the side benefit of
gathering a lot of raw materials (used as containers
for the O and H) for structural expansion of such a
base.

Another option if going along with the base is to just
shoot regolith to a station and then do all processing
in the station to seperate out the fuel.

Ryan Z

I was thinking of a nearer-term future, prior to the emplacement of mass
drivers on the lunar surface. But in the longer term, yes I certainly
agree that mass driver launch is far more efficient than rocketry, and
yes, I'd sooner see them lift everything in the most common lunar
materials into high orbit, rather than just the oxygen.

Regards,

Mike Combs

From: Ryan Z [mailto:ryjaz@...]
Sent: Friday, March 12, 2004 4:14 PM
To: spacesettlers@yahoogroups.com
Subject: RE: [spacesettlers] RE: Bush Space Plan Unwise?

--- "Combs, Mike" wrote:
> I'd agree that we should expect the tanker to be a
> reusable vehicle, but
> I'm envisioning the tanker shuttling between the
> surface of the moon and
> the rendezvous point.

Why use a tanker and not a stationary space station?
You could then use a mass driver to shoot the fuel to
the base. This owuld also have the side benefit of
gathering a lot of raw materials (used as containers
for the O and H) for structural expansion of such a
base.

Another option if going along with the base is to just
shoot regolith to a station and then do all processing
in the station to seperate out the fuel.

Ahem,

Why would we want to send oxygen back to earth? Or am I missing the idea
completely? If you want more oxygen on earth then plant a tree... Don't
go to the moon and spent millions of dollars to go dig up some ice,
process it and return a can of "perrier-air"

Minerals may be enough but I don't suspect so, they can be found on
earth. No the trick to using the moon if going to be much more as a
platform to interplanetary travel and building ships than anything else
(to start). There may be people living there to supervise the operation
but that will be it.

Anybody else think that we could be building ships out of concrete?
Would anyone like to debate that topic with me? We are in a zero-g
environment here where weight doesn't matter. Hell, it's rather take a
meteorite on a concrete wall than a meteorite on a plastic/metal wall.

Karell Ste-Marie
C.I.O. - BrainBank Inc.

From: Combs, Mike [mailto:mikecombs@...]
Sent: Monday, March 15, 2004 9:14 AM
To: spacesettlers@yahoogroups.com
Subject: RE: [spacesettlers] RE: Bush Space Plan Unwise?

I was thinking of a nearer-term future, prior to the emplacement of mass
drivers on the lunar surface. But in the longer term, yes I certainly
agree that mass driver launch is far more efficient than rocketry, and
yes, I'd sooner see them lift everything in the most common lunar
materials into high orbit, rather than just the oxygen.

Regards,

Mike Combs

From: Ryan Z [mailto:ryjaz@...]
Sent: Friday, March 12, 2004 4:14 PM
To: spacesettlers@yahoogroups.com
Subject: RE: [spacesettlers] RE: Bush Space Plan Unwise?

--- "Combs, Mike" wrote:
> I'd agree that we should expect the tanker to be a
> reusable vehicle, but
> I'm envisioning the tanker shuttling between the
> surface of the moon and
> the rendezvous point.

Why use a tanker and not a stationary space station?
You could then use a mass driver to shoot the fuel to
the base. This owuld also have the side benefit of
gathering a lot of raw materials (used as containers
for the O and H) for structural expansion of such a
base.

Another option if going along with the base is to just
shoot regolith to a station and then do all processing
in the station to seperate out the fuel.

From: Karell Ste-Marie [mailto:stemarie@...]

> Why would we want to send oxygen back to earth? Or am I missing the
idea completely?

No, the proposal wasn't to send the oxygen back to Earth, but to the L-1
point, where a space craft ascending from Earth could fuel up, and then
depart cislunar space. But I think it would be economical to send lunar
oxygen as far down as LEO.

> Minerals may be enough but I don't suspect so, they can be found on
earth.

I tend to agree. Even in the case of platinum from asteroids, I'd only
consider that an outside possibility (and a business far more likely in
the context of an existing industry to build SPS from asteroidal
material than outside it).

> Anybody else think that we could be building ships out of concrete?
Would anyone like to debate that topic with me? We
> are in a zero-g environment here where weight doesn't matter.

Weight doesn't matter, but mass does (in the form of inertia). Still,
it's true that we'll need about that amount of mass for radiation
shielding, even if using low-weight metals for the hull. Unless we can
get clever with the arrangement of the hydrogen tanks...

Regards,

Mike Combs

On Mon, 2004-03-15 at 12:06, Combs, Mike wrote:
> From: Karell Ste-Marie [mailto:stemarie@...]
> > Minerals may be enough but I don't suspect so, they can be found on
> earth.
>
> I tend to agree. Even in the case of platinum from asteroids, I'd
> only consider that an outside possibility (and a business far more
> likely in the context of an existing industry to build SPS from
> asteroidal material than outside it).
>

Although, one item of speculation with respect to asteroids is whether
or not they originally went through stratifications/differentiation. On
earth we find deposits of minerals in concentration due to the
'settling' of the earth's strata. In most cases the reason the minerals
are accessible to us is through volcanic action (gold is found in cracks
when it is driven into them by heat from magma). So the question to be
answers is whether or not asteroids have larger deposits of hard to find
minerals simply because they went through the same stratification but
then broke up latter, giving us access to minerals at depths that are
impossible to get to on earth...

-MM

Sounds like a lottery game, yes we may find one asteroid that will make
the whole trip worthwhile but will we be finding those on a regular
basis?

Furthermore, it takes very valuable materials to finance a trip and
technology that takes you into the billion dollar financing range, the
biggest oil company on the planet would think about it several time
before signing the dotted line even if told that it would be a "sure
thing" and that is would be impossible for *anything* to go wrong.

How much payload of gold would you need to finance a 2 billion dollar
excursion into space? And then how to you return so much mass of such a
metal? You can't just send it through the atmosphere as is, mind you
that would make the most expensive "sunset" at 2pm that the east coast
ever saw as the gold "evaporates" on re-entry.

And if you don't dump it, then you are carrying that weight, no amount
of parachutes will help you there, the weight will just tear them away,
even if made from iron. You can't flide with that weight (plus the
payload will simply be too huge)

With out current technology I don't see a lot of options.

I don't mean to discredit anything (for anyone), I'm not a scientist,
I'm a different kind of evil, I'm the guy that oversees the purchase of
technology equipment, I need to justify those purchases and I also need
to get them approved by the CTO.

If you think politicians are bad, you've never been in a CTO's office -
those guys go straight for the jugular. If you have one thing that could
cost 1000, 500 and 250$ based on features, no amount of crying will get
you anything better than the 250$ model unless you come up with some
rock-solid arguments that he *understands*, trying to dazzle him with
smoke and mirrors and scientific talk is NOT going to work. People don't
sign checks when they don't understand why... Do you give money to
someone knocking at your door when they only reason is "because"

Karell Ste-Marie
C.I.O. - BrainBank Inc.

From: Michael Mealling [mailto:michael@...]
Sent: Monday, March 15, 2004 12:15 PM
To: spacesettlers@yahoogroups.com
Subject: RE: [spacesettlers] RE: Bush Space Plan Unwise?

On Mon, 2004-03-15 at 12:06, Combs, Mike wrote:
> From: Karell Ste-Marie [mailto:stemarie@...]
> > Minerals may be enough but I don't suspect so, they can be found on
> earth.
>
> I tend to agree. Even in the case of platinum from asteroids, I'd
> only consider that an outside possibility (and a business far more
> likely in the context of an existing industry to build SPS from
> asteroidal material than outside it).
>

Although, one item of speculation with respect to asteroids is whether
or not they originally went through stratifications/differentiation. On
earth we find deposits of minerals in concentration due to the
'settling' of the earth's strata. In most cases the reason the minerals
are accessible to us is through volcanic action (gold is found in cracks
when it is driven into them by heat from magma). So the question to be
answers is whether or not asteroids have larger deposits of hard to find
minerals simply because they went through the same stratification but
then broke up latter, giving us access to minerals at depths that are
impossible to get to on earth...

-MM

> From: Karell Ste-Marie [mailto:stemarie@...]

> Sounds like a lottery game, yes we may find one asteroid that
> will make
> the whole trip worthwhile but will we be finding those on a regular
> basis?
>
> Furthermore, it takes very valuable materials to finance a trip and
> technology that takes you into the billion dollar financing range, the
> biggest oil company on the planet would think about it several time
> before signing the dotted line even if told that it would be a "sure
> thing" and that is would be impossible for *anything* to go wrong.

Historically Asteroid mining was intended for bulk materials, not valuable
ones. (They'd be just a spin off.) It's the kind of thing you do if you
want to build lots of SSPSs or space colonies. Though there are good
arguements for trying to drag cometetary ice fragments into earth orbit.
At a few hundred tons arrival mass that's within current technological
limits, and could have similar fuel return to mining the moon.

ANTIcarrot.

My problems (and I would assume this would would your rant) is that
people aren't focusing their energies where they should be, allow me to
explain:

Why would I want to get on a plane just to go pick an apple when I can
plant an apple tree in my backyard? Of course, that requires knowledge,
care and time. Most people don't have the time it takes to do that, and
even less the patience.

However there are some advantages to doing things like that - freedom

Yes, once we are in space we will require materials - however we cannot
assume that it will be worth the expense to bring them back to earth -
that's not realistic.

It may be realistic to bring them back to the moon however, where the
need for those materials is going to be greater (it's expensive for us
to ship there), on that point I completely agree.

Are we sort-of saying the same thing here?

Karell Ste-Marie
C.I.O. - BrainBank Inc.

--- In spacesettlers@yahoogroups.com, "Karell Ste-Marie"
wrote:

> Anybody else think that we could be building ships out of concrete?
> Would anyone like to debate that topic with me? We are in a zero-g
> environment here where weight doesn't matter. Hell, it's rather
> take a meteorite on a concrete wall than a meteorite on a
> plastic/metal wall.

Why yes, there are two people on the SSI list who are attracted to
the idea of building ships out of concrete. You missed the debate by
a month or so, but I'm sure you could re-ignite it.

You may want to consider what Mike wrote, about the greater mass
that now has to be propelled. When considered in light of the rocket
equation you'll have to carry more fuel on the ship. IOW, you've
scaled the whole project up.

Also, consider crack propogation in the hull, and porosity.

TangoMan

Em Seg 15 Mar 2004 14:35, Karell Ste-Marie escreveu:
(...)
> How much payload of gold would you need to finance a 2 billion dollar
> excursion into space?
(...)

Let me see... 1Kg of gold is worth something like 10,000 dollars... Then you
would need something like 200 tonnes of gold to pay the excursion.

Dropping it on Earth would not be that problematic. You can divide it in a few
tens of capsules a few tonnes each and use conventional parachute-assisted
landing or splashdown.

But I doubt that you would get that much space gold using only 2 billion
dollars. Also, since the value of gold is tied to its scarcity, dropping
massive amounts of gold on Earth would like drop the prices and make the
operation unprofitable.

Hi Mike,

its an interesting point to accelerate at the closest point to earth.

Do I get this right if I say the effect is based on delta-v adding
linearly, while kinetic energy grows squared with speed?
Example: 7.9 km/s LEO + 3.3 km/s delta-v gives escape velocity of 11.2
km/s and a kinetic energy of 0.5*(7900+3300)^2 J/kg = 62.72 MJ/kg,
which is just enough to take you away from earth, but you will have no
speed left afterwards.
Alternatively, go down from a potential that adds 1 km/s (or whatever L1
to LEO is). Then accelerate, which gives E=0.5*(1000+7900+3300)^2 J/kg =
74.42 MJ/kg. After getting away from Earth we have left 74.42-62.72 =
11.7 MJ/kg, which translates to a speed of sqrt(2*11.7 MJ/kg) = 4.84
km/s. 5 km/s generated from 1 km/s! Magic, magic.

For going up the 1km/s potential in the beginning we have to pay a
delta-v of 1 km/s from LEO, which is only 0.5 MJ/kg. At a first glance
this looks like we are creating energy from nothing. But if we look at
it closer, we have to use some mass/fuel to achieve that 1 km/s delta-v.
And to get that mass/fuel from somewhere to LEO (which has a speed of
7.9 km/s) takes a lot of energy.

So your way of explaining it as using the high potential of the fuel
added at L1 is a good point of view too, I'd say.
To rendevous with the fuel in LEO the difference in kinetic energy would
have to be killed first (e.g. by aerobraking the fuel) and will be
wasted. Unless of course we would use inverted aerobraking to transfer
the energy more directly to the space ship. Inverted aerobraking seems
to be a good idea for any delta-v between fuel and space ship larger
than somewhere between 1/2 to 2/3 of typical exhaust speeds of the fuel
when used in traditional rocket propulsion, say like 3 km/s or more (see
http://walthelm.net/inverted-aerobraking.html for details).

But either way (if you believe inverted aerobraking is feasible or not),
bringing fuel from the moon or NEO-asteroids to LEO is still
energetically cheaper than bringing it from earth. And from the space
side you have more time to create the necessary delta-v.

So I'd say we should do both: use some of the fuel from space to get the
space ship from LEO to L1, and then add more fuel for the trip to mars
and beyond.

Regards,
Axel

Combs, Mike wrote: