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NASA studies new booster (UPI)
Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Scott Lowther wrote: Dick Morris wrote: That original paragraph is a bit misleading, by itself. Read the rest of the original (4 May) post and you will see that I propose using the orbiter stage of a (two-stage) VTOL RLV to do the TMI burn, after being refueled in LEO. Well, there goes the whole "affordable" thing.... Non-sequitur. I'd like to see your reasons for believing that a mostly expendable HLLV would be cheaper. The Mars-bound payload, incidentally, would be integrated with the orbiter on the ground, so there would be no on-orbit assembly required. A Shuttle-class paylosd is all that you want for a manned Mars mission? We can do quite a bit with 80,000 lb. [deleted] For example, the orbiter stage of a ballistic RLV would, necessarily, have landing gear, so it could land on the Moon. And would it have this useless-on-Eath landing gear on regular launch flights? Or would it have a completely separate landing gear? And would it have a deletable TPS system for lunar flights? or would it carry that weight all the way to the moon and back? The Earth landing gear would work just fine on the Moon. And unless you plan on a one-way trip, you *have* to carry the heat shield all the way to the Moon and back. Lunar LOX will make the additional penalty of carrying it down to the surface and back quite affordable. Doing that will be cheaper for quite a while than developing a new system, without TPS, that could be based on the Moon. It would *have* to based on the Moon since, lacking a TPS we would not be able to bring it back to Earth. Bringing it back to LEO for servicing would require propulsive braking, which would require about twice the delta-v capability that it would need just to go between the lunar surface and LLO. Having two separate vehicles would also require transferring payloads in zero-g. In short... a do-everything stage is a neat idea, but impractical with conventional chemical propellants. Developing separate vehicles for each application is impractical with any propellants. Propellants are cheap, so spending a lot of money developing special purpose hardware that is highly optimized for minimum mass just to save a modest amount of propellants does not pay. But having a common, reusable launch system for many different applications could save 10's of billions of dollars. [deleted] |
#492
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NASA studies new booster (UPI)
Dick Morris wrote:
I'd like to see your reasons for believing that a mostly expendable HLLV would be cheaper. I have not proposed such a thing, so I see no reason to provide a rationale for it. -- Scott Lowther, Engineer Remove the obvious (capitalized) anti-spam gibberish from the reply-to e-mail address |
#494
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NASA studies new booster (UPI)
Michael Gallagher wrote in message . ..
We have maps of the Moon and Mars at resolutions Lewis and Clark never dreamed of. I don't see why you keep denying the obvious. I am not denying anything; I am saying that even with all that, we have barely scratched the surface. Then by your logic, Lewis and Clark "barely scratched the surface." Did that mean we needed a hundred Lewis and Clark expeditions before anyone could settle the American West? .... Settlement means establishing permanent homes, villages, towns, and cities --not conducting "extended" campouts. Then what President Bush is talking about, particularly WRT the Moon, is more akin to modern military bases -- a "presence" on foriegn soil that people are rotated in and out of. US military bases are established to protect the United States, not to provide entertainment. There are no Moonmen threatening the United States, so why do we need to establish military bases there? No one is talking about an *infinite* series of anything, and these expiditions would be from Bases on the Moon or Mars to other parts of those bodies. Did I say they wouldn't be from the Moon or Mars? That doesn't explain why we need military bases on the Moon or Mars or why you think the rest of us must stay home. The real Lewis and Clark conducted only one expedition, and it had one specific goal -- to enable the immediate opening of the American West to settlement and commercial exploitation. And you are saying we don't need to do anymore of that, we can just go ahead to colonization and hang learning the lay of the land first. We already know the lay of the land, down to a few centimeters. Why do you keep on denying that -- and then denying that you denied it? I disagree. Yes, we have maps and data Lewis and Clark couldn't have dreamed of, and even then, we have barely scratched the surface. How much subsurface data do you think Lewis and Clark collected? Did they even have a seismograph? I doubt you will find a reputable planetary scientist anywhere who will disagree with that. I'm sure planetary scientists are well aware of how much data they have compared to what Lewis and Clark had. Besides, where is it written that no one is allowed to live in a place until the scientists are through studying it? |
#495
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NASA studies new booster (UPI)
Michael Gallagher wrote in message . ..
On 4 May 2004 16:03:00 -0700, (Edward Wright) wrote: ..... You're still talking about an infinite series of "Lewis and Clark expeditions" for no discernable purpose except to enable more "Lewis and Clark expeditions." No one is talking about an *infinite* series of anything, and these expiditions would be from Bases on the Moon or Mars to other parts of those bodies. The Corps of Discovery had ample experience in exploring wilderness, living outdoors, etc. For them the new bit in their exploration was the territory. Trekking through Oregon is not all too different from trekking through Virginia, except you don't know where anything is ahead of time. For the Moon it's switched around. We know a fair amount about the territory, but we have very little experience in doing anything there. Walking around the Moon is quite a lot different than walking around Nevada. |
#496
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NASA studies new booster (UPI)
Scott Lowther wrote: Dick Morris wrote: I'd like to see your reasons for believing that a mostly expendable HLLV would be cheaper. I have not proposed such a thing, so I see no reason to provide a rationale for it. OK, how about a link to the design you *are* proposing. -- Scott Lowther, Engineer Remove the obvious (capitalized) anti-spam gibberish from the reply-to e-mail address |
#497
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NASA studies new booster (UPI)
Scott Lowther wrote: Dick Morris wrote: I'd like to see your reasons for believing that a mostly expendable HLLV would be cheaper. I have not proposed such a thing, so I see no reason to provide a rationale for it. OK, show your reasons for believing that what you are proposing would be cheaper. -- Scott Lowther, Engineer Remove the obvious (capitalized) anti-spam gibberish from the reply-to e-mail address |
#498
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NASA studies new booster (UPI)
Dick Morris wrote:
Scott Lowther wrote: Dick Morris wrote: I'd like to see your reasons for believing that a mostly expendable HLLV would be cheaper. I have not proposed such a thing, so I see no reason to provide a rationale for it. OK, how about a link to the design you *are* proposing. I have already suggested an Ares-type vehicle. Boosters reusable, rpopulsion module reusable, ET used on-orbit. Consequently, "mostly expendable" is not a relevant description. -- Scott Lowther, Engineer Remove the obvious (capitalized) anti-spam gibberish from the reply-to e-mail address |
#499
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NASA studies new booster (UPI)
On 6 May 2004 16:35:53 -0700, (Edward Wright)
wrote: A roundtrip to the Moon does not take years .... A round trip to Mars does. ..... and we have far more data on the Moon than European explorers had on the New World. And there's still more to be collected. We want to put more people on the Moon and start sooner than the timid "initiative" that you consider holy writ. If that's possible, great. If it can be coordinated with Bush's initiative, even better. But if it doesn't look like that's going to happen, then axiong Bush's "timid initiative" results in no one going anywhere. Why should we defer all those things just because you are "not interested" in any significant human space activity? I never said I wasn't interested in that. See above. ----== Posted via Newsfeed.Com - Unlimited-Uncensored-Secure Usenet News==---- http://www.newsfeed.com The #1 Newsgroup Service in the World! 100,000 Newsgroups ---= 19 East/West-Coast Specialized Servers - Total Privacy via Encryption =--- |
#500
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NASA studies new booster (UPI)
On 6 May 2004 17:24:44 -0700, (Edward Wright)
wrote: Michael Gallagher wrote in message . .. No one is calling for an "endless" series of missions, Really -- you called for an end to "Lewis and Clark" missions?.... No, I didn't say that, either. I am saying it may be premature to declare the "Lewis and Clark" phase over. ..... *Why* would sending three or four astronauts be a better way to find it than sending hundreds of scientists, engineers, and other specialists? These days, "astronaut" includes scientists, engineers, and other specialists under the headings of mission and payload specialists. They've been a regular part of Shuttle crews for about twenty years now, and I see no reason why NASA would abandon that model in building a Moon base. Furthermore, a base could have hundreds of specialists rotate through it during the years of its operation. And the base could grow over time, until it has hundreds of people on it. The CATS architectures you and Rand are talking about could provide the infrastructure to expand the base and rotate crews and materials through it. So everybody wins. ----== Posted via Newsfeed.Com - Unlimited-Uncensored-Secure Usenet News==---- http://www.newsfeed.com The #1 Newsgroup Service in the World! 100,000 Newsgroups ---= 19 East/West-Coast Specialized Servers - Total Privacy via Encryption =--- |
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