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SSTO's would have made possible Arthur C. Clarke's vision of 2001.



 
 
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  #1  
Old July 19th 11, 04:21 PM posted to sci.space.policy,sci.astro,sci.physics,sci.space.history,rec.arts.sf.science
Robert Clark
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Posts: 1,150
Default SSTO's would have made possible Arthur C. Clarke's vision of 2001.

This discussion thread on the SecretProjects forum, showed such
SSTO's were already being proposed in the 60's, as well as ambitious
lunar exploration proposals as exemplified by the lunar bases in the
film, 2001:

ROMBUS, Pegasus, Ithacus .
http://www.secretprojects.co.uk/foru...p?topic=4577.0

We didn't have the required high efficiency kerosene or hydrogen
engines in the 60's. But we did in the 70's with the NK-33 for
kerosene and the SSME's for hydrogen.


Bob Clark


On Jul 4, 12:28*pm, Robert Clark wrote:
Space Travel: The Path to Human Immortality?
Space exploration might just be the key to human beings surviving mass
genocide, ecocide or omnicide.
July 24, 2009
"On December 31st, 1999, National Public Radio interviewed the
futurist and science fiction genius Arthur C. Clarke. Since the author
had forecast so many of the 20th Century's most fundamental
developments, the NPR correspondent asked Clarke if anything had
happened in the preceding 100 years that he never could have
anticipated. 'Yes, absolutely,' Clarke replied, without a moment's
hesitation. 'The one thing I never would have expected is that, after
centuries of wonder and imagination and aspiration, we would have gone
to the moon ... and then stopped.'"http://www.alternet.org/news/141518/space_travel:_the_path_to_human_i...

I remember thinking when I first saw 2001 as a teenager and could
appreciate it more, I thought it was way too optimistic. We could
never have huge rotating space stations and passenger flights to orbit
and Moon bases and nuclear-powered interplanetary ships by then.
That's what I thought and probably most people familiar with the space
program thought that. And I think I recall Clarke saying once that the
year 2001 was selected as more a rhetorical, artistic flourish rather
than being a prediction, 2001 being the year of the turn of the
millennium (no, it was NOT in the year 2000.)
However, I've now come to the conclusion those could indeed have been
possible by 2001. I don't mean the alien monolith or the intelligent
computer, but the spaceflights shown in the film.
It all comes down to SSTO's. As I argued previously [1] these could
have led and WILL lead to the price to orbit coming down to the $100
per kilo range. The required lightweight stages existed since the 60's
and 70's for kerosene with the Atlas and Delta stages, and for
hydrogen with the Saturn V upper stages. And the high efficiency
engines from sea level to vacuum have existed since the 70's with the
NK-33 for kerosene, and with the SSME for hydrogen.
The kerosene SSTO's could be smaller and cheaper and would make
possible small orbital craft in the price range of business jets, at a
few tens of millions of dollars. These would be able to carry a few
number of passengers/crew, say of the size of the Dragon capsule. But
in analogy with history of aircraft these would soon be followed by
large passenger craft.
However, the NK-33 was of Russian design, while the required
lightweight stages were of American design. But the 70's was the time
of detente, with the Apollo-Soyuz mission. With both sides realizing
that collaboration would lead to routine passenger spaceflight, it is
conceivable that they could have come together to make possible
commercial spaceflight.
There is also the fact that for the hydrogen fueled SSTO's, the
Americans had both the required lightweight stages and high efficiency
engines, though these SSTO's would have been larger and more
expensive. So it would have been advantageous for the Russians to
share their engine if the American's shared their lightweight stages.
For the space station, many have soured on the idea because of the ISS
with the huge cost overruns. But Bigelow is planning on "space hotels"
derived from NASA's Transhab[2] concept. These provide large living
space at lightweight. At $100 per kilo launch costs we could form
large space stations from the Transhabs linked together in modular
fashion, financed purely from the tourism interests. Remember the low
price to orbit allows many average citizens to pay for the cost to
LEO.
The Transhab was developed in the late 90's so it might be
questionable that the space station could be built from them by 2001.
But remember in the film the space station was in the process of being
built. Also, with large numbers of passengers traveling to space it
seems likely that inflatable modules would have been thought of
earlier to house the large number of tourists who might want a longer
stay.
For the extensive Moon base, judging from the Apollo missions it might
be thought any flight to the Moon would be hugely expensive. However,
Robert Heinlein once said: once you get to LEO you're half way to
anywhere in the Solar System. This is due to the delta-V requirements
for getting out of the Earth's gravitational compared to reaching
escape velocity.
It is important to note then SSTO's have the capability once refueled
in orbit to travel to the Moon, land, and return to Earth on that one
fuel load. Because of this there would be a large market for passenger
service to the Moon as well. So there would be a commercial
justification for Bigelow's Transhab motels to also be transported to
the Moon [3].
Initially the propellant for the fuel depots would have to be lofted
from Earth. But we recently found there was water in the permanently
shadowed craters on the Moon [4]. Use of this for propellant would
reduce the cost to make the flights from LEO to the Moon since the
delta-V needed to bring the propellant to LEO from the lunar surface
is so much less than that needed to bring it from the Earth's surface
to LEO.
This lunar derived propellant could also be placed in depots in lunar
orbit and at the Lagrange points. This would make easier flights to
the asteroids and the planets. The flights to the asteroids would be
especially important for commercial purposes because it is estimated
even a small sized asteroid could have trillions of dollars worth of
valuable minerals [5]. The availability of such resources would make
it financially profitable to develop large bases on the Moon for the
sake of the propellant.
Another possible resource was recently discovered on the Moon: uranium
[6]. Though further analysis showed the surface abundance to be much
less than in Earth mines, it may be that there are localized
concentrations just as there are on Earth. Indeed this appears to be
the case with some heavy metals such as silver and possibly gold that
appear to be concentrated in some polar craters on the Moon [7].
So even if the uranium is not as abundant as in Earth mines, it may be
sufficient to be used for nuclear-powered spacecraft. Then we wouldn't
have the problem of large amounts of nuclear material being lofted on
rockets on Earth. The physics and engineering of *nuclear powered
rockets have been understood since the 60's [8]. The main impediment
has been the opposition to launching large amounts of radioactive
material from Earth into orbit above Earth. Then we very well could
have had nuclear-powered spacecraft launching from the Moon for
interplanetary missions, especially when you consider the financial
incentive provided by minerals in the asteroids of the asteroid belt.

* * Bob Clark

1.)Newsgroups: sci.space.policy, sci.astro, sci.physics,
sci.space.history
From: Robert Clark
Date: Sat, 25 Jun 2011 21:36:07 -0700 (PDT)
Subject: A kerosene-fueled X-33 as a single stage to orbit
vehicle.http://groups.google.com/group/sci.s...b9bcc5ca2dc05?...

2.)TransHab.http://en.wikipedia.org/wiki/TransHab

3.)Private Moon Bases a Hot Idea for Space Pioneer.
by Leonard David, SPACE.com's Space Insider Columnist
Date: 14 April 2010 Time: 02:23 PM EThttp://www.space.com/8217-private-moon-bases-hot-idea-space-pioneer.html

4.)Mining the Moon's Water: Q & A with Shackleton Energy's Bill Stone.
by Mike Wall, SPACE.com Senior WriterDate: 13 January 2011 Time: 03:57
PM EThttp://www.space.com/10619-mining-moon-water-bill-stone-110114.html

5.)Riches in the Sky: The Promise of Asteroid Mining.
Mark Whittington, Nov 15, 2005http://www.associatedcontent.com/article/11560/riches_in_the_sky_the_...

6.)Uranium could be mined on the Moon.
Uranium could one day be mined on the Moon after a Japanese spacecraft
discovered the element on its surface.
By Julian Ryall in Tokyo 4:58PM BST 01 Jul 2009http://www.telegraph.co.uk/science/space/5711129/Uranium-could-be-min...

7.)Silver, Gold, Mercury and Water Found in Moon Crater Soil by LCROSS
Project.
Catherine Dagger, Oct 22, 2010http://www.associatedcontent.com/article/5922906/silver_gold_mercury_...

8.)NERVA.http://en.wikipedia.org/wiki/NERVA


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  #2  
Old October 22nd 13, 03:43 PM posted to sci.space.policy,sci.astro,sci.physics,sci.space.history,rec.arts.sf.science
David Spain
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Posts: 2,486
Default SSTO's would have made possible Arthur C. Clarke's vision of2001.

On 10/22/2013 9:32 AM, Robert Clark wrote:
[snip]

SpaceX Hit Huge Reusable Rocket Milestone with Falcon 9 Test Flight (Video)
By Mike Wall, Senior Writer | October 17, 2013 02:01pm ET
http://www.space.com/23230-spacex-fa...milestone.html

SpaceX also plans to transition the half-scale Grasshopper VTVL test vehicle
to a full scale Falcon 9 first stage:

Final flight of Grasshopper v1.0 sets new record.
By Brian Dodson
October 14, 2013
http://www.gizmag.com/grasshopper-re...-record/29384/

[snip]
Bob Clark


Bob these links are truncated. Do you have the full links?

Thanks,
Dave

  #3  
Old October 22nd 13, 03:58 PM posted to sci.space.policy,sci.space.history,rec.arts.sf.science
David Spain
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Posts: 2,486
Default SSTO's would have made possible Arthur C. Clarke's vision of2001.

Newsgroups sci.astro and sci.physics elided...

On 10/22/2013 9:32 AM, Robert Clark wrote:

Final flight of Grasshopper v1.0 sets new record.
By Brian Dodson
October 14, 2013
http://www.gizmag.com/grasshopper-re...-record/29384/

This article says this "Grasshopper 2", as it were, would have all 9
engines of the regular F9 first stage. However, discussions on other forums
have said it would only have 3 engines. That would make sense since on stage
return, you are using at most 3 engines, and moreover this way, you would
not be risking an expensive loss of 9 copies of the Merlins during these
Grasshopper test flights.
Still, in point of fact there would be an advantage of using all 9 engines
on this first stage Grasshopper, and with a full propellant load. In
November, 2012 Elon Musk gave a lecture in London at the Royal Aeronautical
Society.


Bob do you know if they are replacing the other 6 engines with mass
equivalent dummy mass? From the other forums which 3 are staying? The 3
across the center bisection? Would it not might make sense to preserve
the nozzles in the octaweb configuration to keep the aerodynamics as
close to actual as possible?

Dave

  #4  
Old October 22nd 13, 06:13 PM posted to sci.space.policy,sci.astro,sci.physics,sci.space.history,rec.arts.sf.science
Jeff Findley[_2_]
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Posts: 1,388
Default SSTO's would have made possible Arthur C. Clarke's vision of 2001.

In article , [email protected]
127.0.0.1 says...

Bob these links are truncated. Do you have the full links?



SSTO's would have made possible Arthur C. Clarke's vision of 2001.
http://tinyurl.com/meucpvu

SSTO's would have made possible Arthur C. Clarke's vision of 2001.
http://tinyurl.com/m7q6cvs

Jeff
--
"the perennial claim that hypersonic airbreathing propulsion would
magically make space launch cheaper is nonsense -- LOX is much cheaper
than advanced airbreathing engines, and so are the tanks to put it in
and the extra thrust to carry it." - Henry Spencer
  #5  
Old October 22nd 13, 09:09 PM posted to sci.space.policy,sci.astro,sci.physics,sci.space.history,rec.arts.sf.science
Rick Jones
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Default SSTO's would have made possible Arthur C. Clarke's vision of 2001.

In sci.space.history Robert Clark wrote:
Elon Musk lecture at the Royal Aeronautical Society - YouTube.
http://www.youtube.com/watch?v=wB3R5Xk2gTY


About 30 minutes in, he gave the propellant fraction of the new Falcon 9
v1.1 as around 96%, or perhaps 95.5%. The 96% propellant fraction number
gives a 25 to 1 mass ratio. But at an Isp of 311 s for the Merlin 1D, the
rocket equation gives a delta-v of 311*9.81ln(25) = 9,800 m/s. Since the
delta-v to orbit is only about 9,100 m/s, this would allow a significant
amount of payload.
Then using the 9 engines and the full propellant load on the F9 first stage
would allow in fact not just a VTVL test vehicle, but in fact a fully
reusable and fully orbital vehicle.


Modulo the small matter of a re-entry shield no?

rick jones
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it is one of "Ring Around the Rosy" or perhaps "Duck Duck Goose."
- Rick Jones
these opinions are mine, all mine; HP might not want them anyway...
feel free to post, OR email to rick.jones2 in hp.com but NOT BOTH...
  #6  
Old October 22nd 13, 11:03 PM posted to sci.space.policy,sci.space.history,rec.arts.sf.science
David Spain
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Posts: 2,486
Default SSTO's would have made possible Arthur C. Clarke's vision of2001.

On 10/22/2013 4:09 PM, Rick Jones wrote:
In sci.space.history Robert Clark wrote:
Elon Musk lecture at the Royal Aeronautical Society - YouTube.
http://www.youtube.com/watch?v=wB3R5Xk2gTY


About 30 minutes in, he gave the propellant fraction of the new Falcon 9
v1.1 as around 96%, or perhaps 95.5%. The 96% propellant fraction number
gives a 25 to 1 mass ratio. But at an Isp of 311 s for the Merlin 1D, the
rocket equation gives a delta-v of 311*9.81ln(25) = 9,800 m/s. Since the
delta-v to orbit is only about 9,100 m/s, this would allow a significant
amount of payload.
Then using the 9 engines and the full propellant load on the F9 first stage
would allow in fact not just a VTVL test vehicle, but in fact a fully
reusable and fully orbital vehicle.


Modulo the small matter of a re-entry shield no?

rick jones


Well there is that, but also note that not all that propellant can be
used for uplift. Some has be kept in reserve for the landing. Doesn't
that affect the mass ratio? Using Bob's figures there is a ~700 m/s
leeway in delta-v, but each unit drop of the mass ratio is a 125 m/s
loss in delta-v. Go down ~5 1/2 units and you're not at SSTO any longer.

If 30% of the propellant is kept in reserve how would that effect the
mass ratio?*

Dave

*Aerospace is not my specialty. I could probably spend an hour+
researching the answer for myself, or just ask the group and wait for
the answer. I'm lazy. I'll take option #2. ;-)

  #7  
Old October 22nd 13, 11:09 PM posted to sci.space.policy,sci.space.history
David Spain
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Posts: 2,486
Default SSTO's would have made possible Arthur C. Clarke's vision of2001.

On 10/22/2013 6:03 PM, David Spain wrote:
If 30% of the propellant is kept in reserve how would that effect the
mass ratio?*


Admittedly that reserve figure may be too high.

Dave


 




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