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The 5.2 meter diameter exterior of Shuttle C is totally inadequate for any reasonably proportioned aeroshell type transhab with adequate mass to carry more than two people at a time to Mars and support them for the surface stay. Just how you propose to fit Zubrin's 10m "tuna can" on Shuttle C is beyond me. Nothing smaller than Ares can support Zubrin's Mars Direct. Shuttle C's payload capacity is grossly inferior to Ares.
The 5.2 meter shroud was for the Shuttle C studies related to launching Space Stattion Freedom back in the late 1980's. Martin considered many different styles of payload fairing, including fairings as big as 8.7 meters for "Shuttle C block II." Similarly large fairings would have been needed for "ISS option C," a single-piece space station tha would be launched by a shuttle-derived booster.
When the term "Shuttle C" is used in the context of this forum, it can refer to any shuttle derived boosterwhich replaces the orbiter with a payload element. Perhaps "Shuttle Derived Vehicle," or "SDV," would be more appropriate. Prior to Shuttle C, there was a similar concept called IHLLV. After Shuttle C was scrapped (because it was tied to SSF,) NASA looked at SDV's, essentially resurrected Shuttle C's, for launching components of the Mars spacecraft.
Because Shuttle C was never built, it is not fair to judge its cargo capacity. In theory, the SDV's payload, including any payload fairings, would approximate the weight of the shuttle orbiter (~100 tonnes.) This number can decrease based on the modifications needed to build the SDV, or it can increase if newer technology (RS-68 engines, five-segment solid rocket boosters) is worked into the design.
But you will not see any HLLV's built as long as there is no demand from the commercial sector for one. Of course, there doesn't need to be a demand from the market if government(s) decide to go to Mars. If NASA ever decides to take part in humans-to-Mars, an SDV would minimize redundant costs by using shuttle facilities, launch pads, tankage, and boosters (five-segment solids are being considered as a shuttle upgrade.) An all-Europe show would be better off with Energia's services because it doesn't have access to anything shuttle-related.
"I'm not much of a 'hands-on' evil scientist."--Dr. Evil, "Goldmember"
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Re. facilities available to support the new Energia M,
To clarify, I meant that no part of MIK-RN is needed. I am not suggesting that the low bays of this building should be used, as Starsem currently uses them for other purposes. Neither Energia M operations from Baikonur, nor Energia Mars International HLLV operations from Kourou require any part of MIK-RN at site 112 to be repaired.
http://www.starsem.com/index.html
Parts of the giant MIK-OK building on site 254 are currently used by RKK(RSC) Energia for Soyuz and Progess pre-launch processing. In another section of this building, they also process the Block D upper stage used on Proton. The Energia M upper stage can be processed in this section because Energia M replaces Proton. The new Energia M upper stage is identical to that already planned for the Angara heavies.
http://www.russianspaceweb.com/baikonur … a_254.html
Energia M payloads can be processed in building 92A-50, which currently processes Proton payloads.
http://www.russianspaceweb.com/baikonur_proton.html
MZK is available for main stage processing and final assembly of the entire launch vehicle.
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I have never suggested production of complete Energia launch vehicles duplicating those flown with Buran/Polyus be restarted. I have never argued that the same former Soviet firms and subcontractors be 100%, or even 50% responsible for the overall Mars HLLV programme, or that the RKA provide most of the funding for this launch vehicle.
Mark, please clarify just exactly what "obstacles" you are talking about? Nothing you have said bears any relevance whatsoever to the plan I am promoting. It is indeed possible that the original tooling for the core tank production has been destroyed. How is this supposed to effect EADS? You and I may not have details as to the exact condition of all the Energia-Buran support facilities at Baikonur. So what? How does this effect Kourou?
Mark, why continue to repeat your incredibly misleading propaganda? Although I hope that the Russian economy may continue to improve, my proposal is not in the least dependant upon any such growth. The level of Russian participation in the International programme I propose is limited almost exclusively to contributions to the HLLV. These contributions would require about 20% of the existing RKA budget. As I have demonstrated, such funds will be readily available once the Progress ISS re-supply programme is wound down.
If you're changing the configuration of Energia, can you still call it "Energia" ? All of these changes will require more R&D and more money spent on tooling. RSC-Energia may or may not have cut the tooling for an inline upper stage, but I'm inclined to believe they didn't based on what I've seen. Farming the "new Energia" out to new companies and building new launch facilities at Korou would negate the benefis of resurrecting Energia because it's an extra expense. Rebuilding an old vehicle is advantageous when it represents a savings in cost, but money spent on totally re-inventing an old vehicle might be better spent on something newer and better.
I understand now your arguments about how Energia could be restarted with an infusion of European cash. But I don't think it's safe to say there is a future for a commercialized Energia-M when the launch market is doing so poorly. Finishing the development for Energia-M would also represent an extra cost on top of resurrecting and modifying Energia.
My "incredibly misleading propaganda?" :angry: I seek not to deceive, and I must apologize if you jumped to the conclusion that I was trying to lump Energia with Saturn V when the Saturn would be much more impractical to resurrect. I believe that Energia production would be practical, but only if the original tooling is mostly intact and the existing facilities are used.
It is unfair to say at this point whether a Shuttle Derived Vehicle or Energia would be better for humans-to-Mars without a detailed study. Such a project should take into account the R&D costs of building the SDV and modifications to the baseline Energia; it should look at current payload capabilities and opportunities for future growth, and it should also examine the operating costs for both types. A humans-to-Mars mission may also be served by combining elements from Energia, the shuttle, and the EELV's. The reason I argue for an SDV is because I believe that the existence of facilities to build and operate the vehicle, in addition to the availability or ongoing production of the vehicle's main elements, will outweigh the expenses associated with forming a new production line and rebuilding or replacing damaged infrastructure.
"I'm not much of a 'hands-on' evil scientist."--Dr. Evil, "Goldmember"
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Mark S,
You accuse me of "totally reinventing" Energia, then you proceed to say that the term "Shuttle C" can rightly be used to describe any "SDV", using RS-68s, ARSBs, differing shroud dimensions, or whatever other major variations suit your fancy. It is perfectly fair to judge the cargo capacity of the thing that everyone in the world except you recognizes as what is meant by "Shuttle C". Here it is:
http://www.astronautix.com/lvs/shuttlec.htm
If you wish to reject the possibility of having Europe, Russia, Ukraine etc. cover most of the Earth to Mars transport costs of an International Humans to Mars programme, and insist upon a Shuttle derived launch vehicle, then it makes much more sense to back Ares than Shuttle C. Ares is far more suitable for Humans to Mars applications.
Here we go again. Forgive me if I am repeating myself. Zenit is in demand from the commercial sector. Vulcain 2, which can be used to power the Energia derived Main Core stage is in commercial production for commercial consumption. The market for Proton is real, therefore the market for a vehicle cheaper to operate than Proton, with equal or better performance, is real. An evolved Energia M commercial Proton replacement will be quicker to develop and cheaper to operate than Angara 5 and Angara 5-UOHB. This remains true even if new tooling is required to fabricate the Energia M core tank. This same Energia M core stage can be used as the upper stage for the Energia derived Mars Programme HLLV, regardless of wether Energia M commercial launchers are ever actually brought into service. This upper stage can be powered by surplus SSMEs or RD-0120s. The only element of this HLLV that that is not in commercial demand or available as surplus is the Main Core Stage. This is basically a big cylindrical tank, not very complex, just an improved/modifed version of what was built and flown years ago. No new technology is required. No magic needed, only some money from the ESA to give to EADS to build it. Is this what you mean by "farming out"?
The fact that no private commercial demand for the delivery of any more than 35 tonnes at a time to LEO exists, nor is ever likely to exist in our lifetimes, is of not the obstacle you make it out to be. The suggestion that we must wait for the market to come up with such a demand is absurd.
The related idea that the mission should be split up into ISS module sized pieces just so that existing commercial launchers can be used is also insane. Why not just wait for the wonderful magical power of the marketplace to bring Humans to Mars all by itself? Why not disband the Mars Society? Why not destroy every public space agency on Earth so that all the funding can go into things governments are supposed to do, like building more bombs? Mark, I know you have not promoted any of the ideas I have mentioned in this paragraph, but there are some people in this world who actually think this way.
What do you mean by "totally reinventing"? This is what I mean by "misleading" remark I was complaining about. Is having EADS build an improved core tank and fitting it with Vulkain 2s "totally reinventing"? The differences between Ares and the current STS launch stack are greater than those between the original "as flown" Energia and the Energia derived system I have described. For example he recoverable Ares SSME pod is a completely new spacecraft. Unlike Energia M, the Ares upper stage is a totally new design. The ASRB is not the same thing as the SRB.
I have always gone to great pains to use terms like "Energia Derived" or "Vulkan ILV" etc., and to make explicitly clear exactly what I was talking about. All the facilites reqired to build it exist and are active. Obviously, some new tooling will be needed for the Energia Main Core and possiblly for the upper stage.
The an Enegia derived HLLV system offers the highest performance, greatest reliability, and lowest cost per tonne delivered to TMI of any other near term launch system I have ever seen. If you don't believe me, believe this:
www.mars.caltech.edu/chris_its/mars/cmsm2r.html
(I hope their server is back up ; )
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If you wish to reject the possibility of having Europe, Russia, Ukraine etc. cover most of the Earth to Mars transport costs
I have to comment on this. Russia is untrustworthy. They screwed up on the ISS, causing our budget to overrun completely. I wouldnt trust russia to build a toilet seat on a humans to mars mission.
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The related idea that the mission should be split up into ISS module sized pieces just so that existing commercial launchers can be used is also insane. Why not just wait for the wonderful magical power of the marketplace to bring Humans to Mars all by itself? Why not disband the Mars Society? Why not destroy every public space agency on Earth so that all the funding can go into things governments are supposed to do, like building more bombs? Mark, I know you have not promoted any of the ideas I have mentioned in this paragraph, but there are some people in this world who actually think this way.
Does the Mars Society support your plan for humans-to-Mars, and would that make me disloyal to the Mars Society for disagreeing with it?
I don't believe that Mars Direct is the best way for getting to Mars, and I don't think that support of Mars Direct and its variants should be a prerequisite for joining the Mars Society.
It should also be noted that Zubrin has not endorsed any particular method for funding humans-to-Mars. International collaboration is one of three options. But Zubrin also suggested a system of cash prizes to finance humans-to-Mars. This plan is more in line with my capitalistic line of thinking. I'm perfectly happy with breaking the spacecraft into more manageable pieces so they can be launced by reusable rockets. I also think that the X-Prize will validate what I and many others believe about the "Mars Prize" that Zubrin and Gingrich dreamed of.
The definition of "Shuttle C" and the more generic "Shuttle Derived Vehicle" have become muddled; I'm getting my information from Romance to Reality. And please don't confuse the five-segment solid with the stillborn ASRM. Five segment solids are a stretched version of the current SRM's, being studied by NASA as a Shuttle upgrade.
Rob, I respect your opinions and I do think your ideas have merit. All I ask is that you share the same respect for me by not being so vitriolic in disagreeing with me.
"I'm not much of a 'hands-on' evil scientist."--Dr. Evil, "Goldmember"
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Ok, can we get away from hyperbole and insults? We are all very passionate about Mars and want to get there within our lifetime. I personally would like to own the company that builds the first colonization ship to Mars. Not the first manned mission to Mars, the first ship to carry colonists for permanent emigration to Mars. I want to see it fly within my lifetime. That means the first exploratory manned mission to Mars must be very soon; we can't wait until 2025.
Rob C Willis and Mark S, you are among the most technically capable individuals I have communicated with on this board. I have communicated with Mr. Willis on the previous message board about the Energia launch vehicle. It is truly refreshing and encouraging to be able to hold meaningful conversations. Let us not start tearing each other down. A humans to Mars program will always require participation by multiple countries. The International Space Station could not have been built without Russian participation: NASA did not have any form of recycling life support system, or a docking mechanism that could handle two craft each of which mass 100 tonnes, such as the space shuttle orbiter and space station. NASA also lacked the means to automatically dock modules in orbit. Russia had these, and still does. Since Apollo has been well and thoroughly eliminated, NASA did not have a capsule or any form of lifeboat for the station; Russia had Soyuz as well as a relatively inexpensive cargo re-supply vessel. Canada contributed the remote manipulator system (CanadArm) for space shuttle, and the space station remote manipulator system (CanadArm2) for ISS. If nothing else, participation by multiple countries is necessary to pay for a mission to Mars. You could argue that Russia didn't contribute money, but they did contribute the necessary technology I already mentioned.
If the Russian news reports that they will abandon Baikonur by 2005 are just bull shit attempts to pressure Kazakhstan to reduce their "rent", then we still have the Energia launch facilities. I have heard various reports of the poor condition of Russian facilities, but the strongest and most detailed criticism is from a major American aerospace company, and large American companies are notorious for slandering their competition. Russia has always built their aircraft, military bases and space facilities so they are robust and can operate after severe weathering has caused major cosmetic damage. Up-to-date, operational Russian air force airfields look to American eyes as if they have been abandoned for decades. The guy I am referring to said that building #112 had major rust on its support walls when I talked to him 1 month before the roof collapsed. Pictures I have from a tour group that went through in April 1997 shows MIK-RN sparkling clean and no rust. The rail tracks leading from MIK-RN to the launch pad have tall weeds growing through them, but the ties are concrete and the rails look like they are in good shape; all they need is someone to mow the weeds. I can't tell the condition of the gantry from the pictures, but it is there. One Buran orbiter was located outside in a safing area, and had a significant number of heat tiles hacked off its nose. This was not the Buran orbiter that flew in space once, but I can't tell if it is one of the other 2 orbiters or one of the full size mock-ups. It does have real tiles, not just a paint job.
I encourage both of you to continue working on new launch vehicle designs. I will still advocate a simple, minimum-change design for the first mission. This could be done with Energia LV using 4 strap-on boosters and EUS to lift large modules into LEO for assembly, or by breaking the mission into independent craft slightly smaller than Mars Direct and using Energia for direct throw to Mars. Then we wouldn't have to develop any Trans-Mars Injection stage, the EUS would be the TMI stage. Shuttle-C doesn't have such a side-mounted stage available, at least not such a large one that could be used for direct throw, but it could lift large modules to LEO. Notice the variation of Shuttle-C that I advocated: the same vehicle assembly and launch facilities as the space shuttle, no change. The same external tank and SRBs, no change. The same total launch mass, thrust profile, and total mass delivered to orbit, no change. The same external diameter as the shuttle orbiter's fuselage to avoid aerodynamic problems or reduced lift from increase drag. The same 3 main engines, same fuel pumps, same Orbital Manoeuvring System (OMS). Replacement of the orbiter by an engine pod with ablative heat shield, X-38 derived parafoil, orbiter launch software and X-38 landing software, and a Titan IV derived fairing means a very low cost, relatively small piece of hardware. The only new launch equipment would be a support pillar to replace the orbiter wing supports on the Mobile Launch Platform (MLP). The only new landing equipment would be a medium flat-bed truck with dual rear axle and a truck crane. The only new equipment onboard such a Shuttle-C engine pod would be a radiation hardened, single board computer, and smaller manoeuvring thrusters; both are available off-the-shelf. This is different than the variation of Shuttle-C depicted in Astronautix; that one uses just 2 SSMEs, is expendable and has lower lift capacity.
Don't worry about the "establishment" not accepting anything non-American. One document I have on Magnum lists several variations, I just keep talking about the variation that is closest to the "baseline" established before the study. Variations include:
- 2 SRB's, ET core with 5 foot stretch, 2 "low pressure" SSME's, kick stage
- 4 SRB's, ET core with 5 foot stretch, 3 "low pressure" SSME's, kick stage
- 2 SRB's, ET core with 5 foot stretch, 2 pressure assist modules with 2 SSME's per module, kick stage
- 2 pump-fed Liquid Rocket Boosters with 3 RD180 per LRB, ET core with 5 foot stretch, 2 "low pressure" SSME's with LOX/RP fuel, kick stage
- 2 pressure fed LRB's with 4 "800K" engines per LRB, ET core with 5 foot stretch, 2 "low pressure" SSME's with LOX/RP fuel, kick stage
- 2 Liquid Flyback Boosters with RD180 type engines, ET core with 5 foot stretch, 2 "low pressure" SSME's with LOX/RP fuel, kick stage
Each of these variations has different development cost, operational cost, and lift capacity. However, notice the use of RD180 engines. Another page of the same document lists the engine options: RS-68, SSME w/PA mod, TRW Eng., RD-170, RD-171, RD-180. Notice the inclusion of Russian engines in design of Magnum, which is a Shuttle derived vehicle.
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Rob D.,
Your points are well taken. Mark S. certainly does deserve respect, and some of my comments have been rather sarcastic. I'll blame this on cultural differences. I'm originally from the U.K., so sarcasm runs in my blood. I'll try to tone things down a little for the American audience.
I must respond to Soph. To date, less than 15 to 20 percent of the total NASA "cost overruns" bill on the ISS programme is in any way even remotely related to "bailing out" those "untrustworthy" Russians. Despite what Boeing and Lock-Mart would like you to think, it is U.S. based firms that have been sucking the lions share of the cost overrun gravy out of NASA. This should make clear exactly who is screwing who.
And now for some more sarcasm in the form of a rhetorical question for Soph (I can't help myself. Sorry):
If you were aboard the ISS and faced with a catastrophic systems failure, would you hop onboard the Soyuz built and paid for by those "untrustworthy" Russians, or hold your breath until a shuttle shows up a few months later?
I said I would tone it down a "little".
Cheers everyone.
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And heres a little nugget for you. My dad had to do a few large jobs in less than a month that the russians bailed out on, and hes just a minor subcontractor. "Boeing and Lock-Mart" arent out to do anything-im basing it on personal experience. Are you going to say that a small contractor is out to screw Russia? Do you even know that most of Boeing and Lockheed's work is done by small contractors?
Dont even begin to say that my father is out to screw NASA-the government is far too powerful. You cant sue the government, you cant force them to pay you, and so on.
15-20% of 100 billion is 15 to 20 billion dollars. That money could be better spent building Mars Direct. I dont know about you, but I would like 15 to 20 billion dollars.
But thats a dumb, irrelevant question. And how much does a Soyuz cost? Im sure it is nothing like 15 to 20 billion dollars.
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On a more serious note,
The Energia derived HLLV is semi-reusable. Zenit Strapons were designed for ten reuses, recoverable by a parachute/airbag system. RD-170 was also required to last for at least ten flights, but has been proven to withstand 20 full duration burns.
STS derived SRBs are more properly described as "recyclable". Again, I don't have exact figures, but it costs almost as much to dismantle, strip down, refurbish, refuel and re-assemble an SRB as it costs to build a new one.
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I just realized Lock-Mart wasnt being deragatory...Lockheed is actually a better way to refer to them. Martin is just retained for contractual reasons.
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Soph,
You have misunderstood and misinterpreted almost everything I have said. Contractors bail out on subcontractors all the time. This is not a uniquely Russian phenomena. What Boeing and Lockheed, as well as Mitsubishi, Krunichev, Ford, Mary Kay Cosmetics and every other corporation is out to do is make as much money as possible. That's the way of the world. Do you deny this?
You have just made a couple rather stupid remarks. I don't live under a rock. I know exactly how money flows through and between large and small businesses. I work for a bank. I never said that your Dad is out to screw Russia, NASA, or anyone else! Where do you get this stuff?
I don't know which United States you live in, but the one I'm familiar with features individuals, small companies and large corporations bringing lawsuits against government agencies all the time. They are sometimes awarded millions of dollars in payments. The newspapers are full of such stories.
Your figures on the ISS are completely wrong. Total programme cost contribution by the U.S. to date is less than 30 billion. You seem to forget there are other participants in the programme, like the ESA, JSA, CSA etc. Thats why they call it the ISS. The 15 to 20 percent figure I quote is not 15 to 20 percent of 30 billion, but a percentage of the COST OVERRUNS. The actual total "bailout" figure that actually ended up as a cash payments from NASA to "the Russians" over the last ten years amounts to less than two billion. Try getting to Mars on that.
Please don't take your Dad's experience out on me.
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I tried to be reasonable, but you are simply moronic.
No, if the government doesnt want you to sue them, you cant. The only exceptions are very large businesses with large clout, or societal issues that have political backing. i guess youre not familiar with the fact that the supreme court only takes cases that it wants to take.
I dont know where i got the $100 billion figure from. However, I would like to know just how international this project is.
Despite what Boeing and Lock-Mart would like you to think, it is U.S. based firms that have been sucking the lions share of the cost overrun gravy out of NASA. This should make clear exactly who is screwing who.
Yes, I guess I just got it right from your words. I must be an idiot.
Im not taking anything out on anybody. So keep your anger to yourself.
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I said you made a couple stupid remarks. I did not call you an idiot. You say you are trying to be reasonable, then proceed to call me a moron. How productive of you. Which one of us has the anger management problem?
I never said it was easy for an idividual to bring to court and win such cases, only that it does happen.
Can we possibly bring the topic back to launch vehicles now?
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You only implied that im stupid in every possible way without saying it.
Let the flamewar end...fine.
I dont think we should be developing HLVs as heavily as we should be developing the space elevator.
I also think we should start investing more into nuclear HLVs. The benefits are so much greater than anything existing, its worth any cost.
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The public will never tolerate nuclear HLVs spewing radioactive exhaust plumes into the atmosphere, let alone be willing to pay for their development
However, I would agree with you that once existing stocks of surplus SSMEs and RD-0120s are used up, a nuclear-thermal upper stage/TMI stage does make a great deal of sense. Once a Mars programme is well under way, money may also be found to develop a nuclear-electric inter orbital tug, which could also be quite cost effective.
In the future, space elevators will provide an excellent method of launching payoads from the surface of Mars and the Moon.
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Radioactive exhaust plumes? Thats an anti-nuclear propoganda line. This simply wouldnt happen. It sounds nice as an anti-nuclear protest line, but its not valid in reality.
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Soph,
You are mistaken. The propellant of all nuclear thermal rocket engines is irradiated as it is heated and expelled.
The Soviets developed the YaRD OKB-456 nuclear/ ammonia engine for the "Superraket" HLLV study back the 1950s, and rejected it because of the level of radioactive contamination it would cause. These are the same people who were perfectly comfortable with the first generation Soviet graphite core reactors , and whose industries had the worst environmental protection record in the world.
I myself have not stood in any nuclear thermal rocket exhaust plumes holding a geiger counter, but in addition to the technical articles I have read, my information comes directly from five different individuals who are expert in the field, four of whom I met at various Mars Society conferences.
One was formerly with the U.S. Air Force. He had worked on the Project Pluto nuclear ramjet. The second had worked for NASA on the NERVA programme. Unfortunately, I don't remember their names, but they both confirmed what I had read.
The third is Richard Lawler, who holds Doctorates in Physics and Chemistry. Although a civillian, he worked on hydrogen slush propellant research for the Air Force.
The fourth is Chris Hirata, an orbital mechanics specialist from Caltech.
The fifth is Dr. James Powell, a nuclear physicist who also happens to be my best friends older brother.
I have discussed nuclear thermal rockets with all of them. They all support their use, but not for booster applications in Earths atmosphere. For the time being, I shall conclude that they are correct, and that you are mistaken.
Perhaps the people who wrote the following are also all liars:
http://www.orionsarm.com/ships/fission.html
http://www.vectorsite.net/tarokt2.html
http://www.fas.org/nuke/space/c07sei_2.htm
I could go on, and on, and on....
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That is quite interesting. Janyce Wynter recently told me that the Pluto nuclear ramjet would not produce radioactive exhaust. Janyce is an aerospace engineer with Bombardier Aerospace, she designs and tests business jets. I tried to work out the radiation effects of a uranium nuclear reactor on air, and found it produces some beta emitters with half-lives measured in seconds, and tritium. Tritium is also a beta emitter but has a much longer half-life. However, not much tritium would be generated. This calculation is different from what Janyce told me, but the extremely short half-life of the majority of the beta emitters in nuclear jet engine exhaust means it will dissipate quickly. The short half-lives are 7.13 and 26.9 seconds. The one with a half-life of 26.9 seconds will decay 99.63% to a non-radioactive form in 2 hours. The one with a half-life of 7.13 seconds will decay 99.90% in that time. Beta radiation is non-infectious and lacks the energy to penetrate beneath the skin, so is that really a hazard?
Tritium has a half-life in years, but only 0.0115% of the hydrogen of moisture in the air is deuterium, and only that would be transmuted into tritium. Most of the neutron radiation will not be absorbed by deuterium in the air, so most of the tiny quantity of deuterium that is in air will flow through without becoming tritium. Is this really a hazard?
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Two questions.
1) How much waste deuterium are we talking about here (per launch, etc)?
2) What happens if a launch vehicle unexpectedly blows up on launch? What kind of cleanup are we looking at, etc?
Some useful links while MER are active. [url=http://marsrovers.jpl.nasa.gov/home/index.html]Offical site[/url] [url=http://www.nasa.gov/multimedia/nasatv/MM_NTV_Web.html]NASA TV[/url] [url=http://www.jpl.nasa.gov/mer2004/]JPL MER2004[/url] [url=http://www.spaceflightnow.com/mars/mera/statustextonly.html]Text feed[/url]
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The amount of solar radiation reaching the surface of the earth totals some 3.9 million exajoules a year.
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I dont really support a nuclear launch from earth either-my thoughts are to send them up on the elevator and use them in space.
I was just throwing an idea out there.
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I was also thinking the exhaust from a ground-launched Nuclear Thermal Rocket would be radioactive, and therefore would not be acceptable until you're in space. It is an interesting idea. If you used liquid hydrogen as the reaction mass, as most NTR designs do, but use hydrogen with all the deuterium removed, then there would be no tritium in the exhaust. In fact, a NTR with pure 1H as its reaction mass would not have any radiation in the exhaust. Hmm, something to think about.
The problem with a ground-launched NTR is what happens in the case of catastrophic failure? As I have mentioned in a previous post, I have seen a video of nuclear reactor workers loading uranium oxide powder into a steel tube to make fuel rods. They just wore white lab coats, a plastic hair cap, and the same plastic gloves you get with oven cleaner. They poked the powder into the tubes with their fingers. Uranium before it goes into the reactor really is that safe. The uranium in Nerva was encased in ceramic capsules so strong that it could fall all the way out of orbit and strike the ground without cracking. The rocket would smash to bits, and you would have uranium fuel capsules littered all over the debris field, but all of the uranium would still be sealed. After a reactor is turned on the nuclear waste is very radioactive. The same video from a nuclear power plant showed a robot removing fuel rods and taking them to a storage pool; you don't want to be in the same room as spent reactor rods. This means launching a NTR upper stage and activating it after it is safely in orbit is just as safe as any rocket launch. However, catastrophic failure of a NTR launch vehicle would be a radioactive mess. All the uranium capsules would remain intact, but after the reactor had been operating the level of radiation from each capsule would be high. Catastrophic failure before the reactor is operational would only require a pair of barbecue tongs and a plastic bag to pick them up. After operation the capsules would be a radiation hazard.
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Yeah, I was reading about the Pluto Nuclear Ramjet or whatever, and apparently that's one of the reasons it was canceled. Not because it had a radioactive exhaust, but because of the failure risk (the nuclear design is very very complicated, and any number ofthings could fail to make the whole system fail). It's impossible to provide 100% no-fail risk. Heh, another thing was that it could theoretically go Mach 3 at 1000 feet, which was sepeculated to create a soundwave so powerful it would tear down property.
Some useful links while MER are active. [url=http://marsrovers.jpl.nasa.gov/home/index.html]Offical site[/url] [url=http://www.nasa.gov/multimedia/nasatv/MM_NTV_Web.html]NASA TV[/url] [url=http://www.jpl.nasa.gov/mer2004/]JPL MER2004[/url] [url=http://www.spaceflightnow.com/mars/mera/statustextonly.html]Text feed[/url]
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The amount of solar radiation reaching the surface of the earth totals some 3.9 million exajoules a year.
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Small world. I also know Janyce. I actually don't remember talking with the Project Pluto guy all that much about the ramjet, but we did talk about NTRs.
At any rate, Just as you and John C. have indicated, the radioactive mess resulting from an NTR explosion in the atmosphere would be infinitely worse than the low level contamination of the exhaust plume from normal operations. I should have mentioned this in my earlier post. Soph was quite right to have questioned my remark on the exhaust issue.
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Bumping lost message.
Yeah, I didn't think the exhaust would be that much of an issue, because even with how crazy the military is, they wouldn't design something that spreads lethal radiation all over the friggin place.
Some useful links while MER are active. [url=http://marsrovers.jpl.nasa.gov/home/index.html]Offical site[/url] [url=http://www.nasa.gov/multimedia/nasatv/MM_NTV_Web.html]NASA TV[/url] [url=http://www.jpl.nasa.gov/mer2004/]JPL MER2004[/url] [url=http://www.spaceflightnow.com/mars/mera/statustextonly.html]Text feed[/url]
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The amount of solar radiation reaching the surface of the earth totals some 3.9 million exajoules a year.
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