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Space review: The vision thing



 
 
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  #1  
Old November 11th 03, 03:19 PM
Kaido Kert
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Default Space review: The vision thing

http://www.thespacereview.com/article/59/1
Jeff Foust writes a good review on the recent buzz over the new vision for
the possible new space policy directions. I found one aspect severely
lacking in the article, though.
It looks like economic and ecologic reasons are totally neglected like
possible triggers or drivers for "the space vision".
Quote:
"What this review makes clear is that there is widespread interest in
developing some kind of vision for NASA in the form of a goal or goals for
human spaceflight beyond Earth orbit. Beyond that general interest, however,
there is little consensus regarding not only what that vision should
be-Moon, Mars, asteroids, or elsewhere-but how that vision should be
developed among the executive and legislative branches and the general
public. That dissonance is a recipe for yet another space policy failure."

As you see, the possible "visions" on the table are only what one would call
destinations. I'd see no purpose on visiting the moon, if it werent for
turning it into economic benefit for humankind later on. I'd think selling a
destination, like it was done with Apollo, would be a tough trick to pull
off the second time around.
But selling a better future for people or their children, either through
potential for clean energy sources from space ( SPS) , prospects of getting
a chance to visit the space for themselves ( space tourism ), utilizing
other vast resources from space apart from energy to make for better living
on earth. That could actually sell, if a coherent plan is put forth, with
measurable progress milestones. Of course, one of the methods to implement a
coherent plan is through a destination like moon, but the reasons for going
there should be clearly stated, and actually serve some useful purpose.
So its still a question of finding a appealing purpose of being in space,
which, then, can be tied to a destination to drive the developments better.
I havent heard of any serious speculations on what that new underlying
purpose might be. Until now, its been a generic "to explore and advance
humankind, expand frontiers". A tough sell which is hard to get behind.

-kert


  #2  
Old November 11th 03, 06:16 PM
Terrell Miller
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Default Space review: The vision thing

"Kaido Kert" wrote in message
...

But selling a better future for people or their children,


NASA's been flying the Spinoffs flag for decades. People stopped believing
them years ago.

I once witnessed a speech made by the guy who invented teh high-pressure
turbopumps used in SSMEs. The guy was blatantly pimping for NASA, adn one of
the "future uses" he claimed for the shuttle was to act as "ambulances" to
take critically ill people to orbiting space hospitals. When I asked him
just how many critically ill people would survive the actual launch, he
replied that that was a myth, the shuttle was way smoother than Apollo, in
fact it pulled fewer Gs than a rollercoaster. To which I replied "okay, how
many critically ill people would survive a roller coaster ride?" Never got
an answer to that one...

either through
potential for clean energy sources from space ( SPS) ,


Bull****. utter bilge. SPS as a ground-based power supply is a massive
boondoggle.

Even the proponents of solar power satellites (or Space Solar Power, for
those trying to evade the subject) eventually have to admit that the launch
and operations costs of SPS are prohibitive, and always will be so as long
as we're stuck using chemical rockets.

To give you some idea: a single SPS would have to be roughly 20-25 square
miles. Has to be, no way to build 'em smaller and still beam enough power
down to Earth to mean anything.

Question: how do you send up enough material into GEO to build that first
SPS? Well, the current idea is to use "millions" (direct quote from several
SPS proponents) of individual modules, each of which is 500-600 feet across
when fully deployed. They get launched individually, then use something like
a solar-to-ion drive (similar to Deep Sace 1) to propel tehmselves into GEO,
where they attach themselves automatically to their fellow modules.
Eventually, the entire SPS is constructed and away we go.

Sounds like a plan, right? Wrong. Each "module" would be "very compact" and
"lightweight", of course. Powersat.com's plan seems to be fairly
representative of the general scheme. It calls for each module to stow into
a 36'x21' launch configuration. (which is too wide to fit in the shuttle
bay, btw, so you have to send it up on its own ELV).

Getting accurate, consistent numbers out of SPS studies is challenging at
best. Powersat.com claims that each module would deploy to be about 600 feet
across, in which case you would need about 2000 to form the entire receiver
(that's totally ignoring the transmitter, which itself is humongous, or the
rectenna on the ground). That's *two thousand* separate boosters just to get
the solar cells on orbit. And since their sales pitch claims that the SPS
would comprise "millions" of individual modules, I'm assuming that the
600x600 configuration is just to propel itself into GEO, at which point it
discards most of its mass.

So at bare minimum, you'd need several thousand launchers just to get the
space-based components for *one* SPS (which would only supply enough power
for *one* large city) into space.

Anybody out there think it's remotely feasible for anybody on Earth to
assemble, check out, and launch a couple thousand boosters within a 5-10
year span? Didn't think so.

Second, there's teh economics of SPS. Frankly, they suck. Even the
proponents of SPS admit that. An SPS would have startup costs roughly 150%
of a similar terrestrial power plant. And then, *maybe*, after 15-25 years
they could get the retail price of the electricity down to 7-10 cents per
kWH. But terrestrial power is currently about 5-6 cents. So *at best*, after
decades of development and improvement, the power from an SPS would be
40-60% more expensive than from a coal-fired or nuke plant. At *best*.

One of life's little ironies is that some of the more prominent space
advocates who criticize NASA because they way overhyped the performance and
profitability of the Shuttle are making *exactly* the same kind of utter
bull**** claims about SPS, and have been doing so for *exactly* the same
length of time that NASA has been bull****ting about the shuttle.

Funny, that...

--
Terrell Miller


"Very often, a 'free' feestock will still lead to a very expensive system.
One that is quite likely noncompetitive"
- Don Lancaster


  #3  
Old November 12th 03, 01:37 AM
Derek Lyons
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Default Space review: The vision thing

"Terrell Miller" wrote:

Anybody out there think it's remotely feasible for anybody on Earth to
assemble, check out, and launch a couple thousand boosters within a 5-10
year span? Didn't think so.


With a properly designed booster, and production/checkout system,
there's no particular reason why a one-launch-a-day rate can't be
sustained indefinitely. (Assuming the money is available and barring
a strike or massive bank failures.)

D.
--
The STS-107 Columbia Loss FAQ can be found
at the following URLs:

Text-Only Version:
http://www.io.com/~o_m/columbia_loss_faq.html

Enhanced HTML Version:
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Corrections, comments, and additions should be
e-mailed to , as well as posted to
sci.space.history and sci.space.shuttle for
discussion.
  #4  
Old November 12th 03, 05:01 AM
Henry Spencer
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Default Space review: The vision thing

In article ,
Derek Lyons wrote:
Anybody out there think it's remotely feasible for anybody on Earth to
assemble, check out, and launch a couple thousand boosters within a 5-10
year span? Didn't think so.


With a properly designed booster, and production/checkout system,
there's no particular reason why a one-launch-a-day rate can't be
sustained indefinitely. (Assuming the money is available...


2000 launches in 10 years is 200/yr, which is only twice the rate that the
Soviets consistently sustained during their busiest launch years. And
much of that traffic was Semyorkas -- fairly complex rockets with a long
checkout/launch cycle. (You wouldn't think anyone would build an ICBM
with a countdown longer than the B-52 flight time from Maine to Plesetsk,
but that's exactly what they did...)

It's not merely remotely feasible, it's clearly and straightforwardly
feasible. Good design in the launcher and the ground-support facilities
will certainly help, but the only part that's *necessary* is ample money.
--
MOST launched 30 June; first light, 29 July; 5arcsec | Henry Spencer
pointing, 10 Sept; first science, early Oct; all well. |
  #5  
Old November 12th 03, 10:11 PM
Stefan Dobrev
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Default Space review: The vision thing

(Henry Spencer) wrote in message ...
In article ,
Derek Lyons wrote:
Anybody out there think it's remotely feasible for anybody on Earth to
assemble, check out, and launch a couple thousand boosters within a 5-10
year span? Didn't think so.


With a properly designed booster, and production/checkout system,
there's no particular reason why a one-launch-a-day rate can't be
sustained indefinitely. (Assuming the money is available...

....
It's not merely remotely feasible, it's clearly and straightforwardly
feasible. Good design in the launcher and the ground-support facilities
will certainly help, but the only part that's *necessary* is ample money.

Does anybody have a clue how much money is needed to design such a
booster (Zenit?, Angara?, ??) and the related automated production and
launch facilities? The scale (thousands of launches) would certainly
justify investing
quite a big $$$ into production/launch automation.

A rocket could (and should), after all, be simpler then the car I am
driving. While it would have much more metal and fuel, the costs of
those should be in the noise (about as much as in my car).

Stefan

P.S. What I would like to see (in addition, and in parallel with the
research into cheap launchers) is basic engineering research into
- simple, low cost and reliable reentry systems (ballutes?, ...)
- how to operate machinery in the lunar environment (dust, thermal
extremes)
- how to process lunar regolith into solar panels (the panels
could be inefficient, but the process should be automatic)
- trying out a small scale rotovator with currently available
technology (spectra?), just to figure out the potential unknown
problems
- ...

All of this done in real space, not just viewgraph engineering.
  #6  
Old November 13th 03, 12:59 AM
Terrell Miller
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Default Space review: The vision thing

"Henry Spencer" wrote in message
...

2000 launches in 10 years is 200/yr, which is only twice the rate that the
Soviets consistently sustained during their busiest launch years. And
much of that traffic was Semyorkas -- fairly complex rockets with a long
checkout/launch cycle. (You wouldn't think anyone would build an ICBM
with a countdown longer than the B-52 flight time from Maine to Plesetsk,
but that's exactly what they did...)

It's not merely remotely feasible, it's clearly and straightforwardly
feasible. Good design in the launcher and the ground-support facilities
will certainly help, but the only part that's *necessary* is ample money.


Henry, will you please take a moment and actually listen to your own
rhetoric?

You just said that a flight rate that has *never* been achieved *anywhere*,
under any political or economic system, and is in fact twice that of the
nearest analog, is "clearly and straightforwardly feasible".

There's *no way* you can make that assertion, amigo. None.

*Possible*, maybe, given all the handwaved requirements you spelled out.

But *clear*, *straightforward* and *feasible*?!?

Look bro, nobody wants a robust space infrastructure more than you and I,
but it's still a pipe dream and will be for decades *at best*, unless we
find a way to dump our chemical rocket dependency. And if that happens, who
knows whether we'll even need SPS anymore, we may find something orders of
magnitude better and cheaper.

--
Terrell Miller


"Very often, a 'free' feestock will still lead to a very expensive system.
One that is quite likely noncompetitive"
- Don Lancaster


  #7  
Old November 13th 03, 03:47 AM
George William Herbert
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Default Space review: The vision thing

Terrell Miller wrote:
"Henry Spencer" wrote:
2000 launches in 10 years is 200/yr, which is only twice the rate that the
Soviets consistently sustained during their busiest launch years. And
much of that traffic was Semyorkas -- fairly complex rockets with a long
checkout/launch cycle. (You wouldn't think anyone would build an ICBM
with a countdown longer than the B-52 flight time from Maine to Plesetsk,
but that's exactly what they did...)

It's not merely remotely feasible, it's clearly and straightforwardly
feasible. Good design in the launcher and the ground-support facilities
will certainly help, but the only part that's *necessary* is ample money.


Henry, will you please take a moment and actually listen to your own
rhetoric?

You just said that a flight rate that has *never* been achieved *anywhere*,
under any political or economic system, and is in fact twice that of the
nearest analog, is "clearly and straightforwardly feasible".

There's *no way* you can make that assertion, amigo. None.

*Possible*, maybe, given all the handwaved requirements you spelled out.

But *clear*, *straightforward* and *feasible*?!?


Yes.

One: Is a rocket necessarily more complex or difficult to manufacture
than a jet airliner or bomber? No. What was Boeing's peak production
of aircraft post-war? I'm looking for some better statistics, but in
the 2003 year to date, arguably one of the worst years for air transport
purchases in a long time, it's 174 aircraft. 14,000 since 1954,
which works out to an annual average of around 280 aircraft.

Two: Is there anything about rocket operations which are inherently
difficult to launch at a rate of one per day, on the launch side?
No. The Russians' limitations on launch rates were due to their
vehicle assembly limits, not their pad facilities. And their rockets
were just sort of well designed for rapid launch from the pad.
Designs done with operability as the major goal from step one
would do much better. The Soyuz flight history, going from the
list in Iaskowitz 3rd edition (1979 onwards) includes quite a
few multiple launches in one day, many more launches with 2 or 3
flying one per day for that many days in a row.

And these are with conventional complicated rockets, albeit well
engineered robust models. BDBs could use 2 orders of magnitude
fewer parts; RLVs will eventually operate with aircraft-like
maintenance requirements.

No credible examination of the historical data and engineering
issues involved can avoid the conclusion that high flight rates
are supportable if there are sufficient payloads. Just looking
at the US experience, and failing to note the real lessons of
the Soviet program, are not credible examinations. What the
Soviets proved was that they could build the infrastructure
for a given flight rate, could expand that on demand, could
build as many rockets as they needed for demand up to about
100 flights a year, and keep their operational tempo and quality
going over the course of a year or longer flying several flights
a week on the average.

The additional infrastructure, rocket production and assembly
capabilities, and staff to support 200 versus 100 flights
per year would be merely incremental. And designing rockets
to be cheaper and easier to assemble and stack and launch
would make it even easier than that.


-george william herbert


  #8  
Old November 13th 03, 04:29 PM
Henry Spencer
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Default Space review: The vision thing

In article ,
Terrell Miller wrote:
It's not merely remotely feasible, it's clearly and straightforwardly
feasible. Good design in the launcher and the ground-support facilities
will certainly help, but the only part that's *necessary* is ample money.


You just said that a flight rate that has *never* been achieved *anywhere*,
under any political or economic system, and is in fact twice that of the
nearest analog, is "clearly and straightforwardly feasible".


Yes. Exactly.

I don't have to have built a dining-room table to assert confidently that
it is possible for me to do so. I *did* design and build the desk I'm now
sitting at; it is not as large as a dining-room table, but it is actually
significantly more complicated. The same tools and skills apply.

In the case of launch *rate*, it's particularly easy. Building rockets
that are ten times bigger can be a technical challenge, but building ten
times as many of the existing design is just a matter of more production
plants. The Soviets showed that they -- with their poor technology and
miserably inefficient economy -- could launch 100 times a year. And that
was never a large fraction of their government spending. Even they could
have launched 200 times a year quite straightforwardly: all they needed
to do was build and staff a second copy of each facility involved. More
manufacturing plants, more assembly buildings, more rail lines, more pads.
The only really scarce resource -- engineering brainpower -- doesn't have
to be duplicated, not when you're just building a second copy of something
that's already debugged. Want 300/year? Build a third copy.

Look bro, nobody wants a robust space infrastructure more than you and I,
but it's still a pipe dream and will be for decades *at best*, unless we
find a way to dump our chemical rocket dependency.


Your obsession with the inadequacy of chemical rockets is not supported by
facts. While not ideal, they are perfectly adequate to get us into orbit
cheaply and conveniently, if built and used properly.
--
MOST launched 30 June; first light, 29 July; 5arcsec | Henry Spencer
pointing, 10 Sept; first science, early Oct; all well. |
  #9  
Old November 14th 03, 05:31 AM
Rand Simberg
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Default Space review: The vision thing

On Wed, 12 Nov 2003 19:59:48 -0500, in a place far, far away, "Terrell
Miller" made the phosphor on my monitor glow
in such a way as to indicate that:

It's not merely remotely feasible, it's clearly and straightforwardly
feasible. Good design in the launcher and the ground-support facilities
will certainly help, but the only part that's *necessary* is ample money.


Henry, will you please take a moment and actually listen to your own
rhetoric?

You just said that a flight rate that has *never* been achieved *anywhere*,
under any political or economic system,


No one has ever attempted it.

and is in fact twice that of the
nearest analog, is "clearly and straightforwardly feasible".

There's *no way* you can make that assertion, amigo. None.


There must *some* way, because he did so. And it's true.

--
simberg.interglobal.org * 310 372-7963 (CA) 307 739-1296 (Jackson Hole)
interglobal space lines * 307 733-1715 (Fax) http://www.interglobal.org

"Extraordinary launch vehicles require extraordinary markets..."
Swap the first . and @ and throw out the ".trash" to email me.
Here's my email address for autospammers:
 




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