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Since Falcon Heavy is supposedly a super-heavy rocket, what do you call something that's on par with Energia?
They're being very sketchy on the details though. There's a Flight Global article here - http://www.flightglobal.com/news/articl … ightglobal
But... 150 tonnes to orbit, and a 7m diameter stage - which means that the payload can be that wide? We'd only need a few launches to build up a Lunar fuel infrastructure, and then we can start taking all 150 tonnes that's launched to the surface and properly build up the base. If we got a launch each month, and it cost $250 million dollars (so about the same cost as Falcon Heavy per tonne)...
After a year spent building up the Lunar infrastructure and fuel depot's, we launch a 150 tonne Mars craft, complete with centrifuge and landers. We then launch the crew in two Dragon launches (why skimp - if we need to, launch the craft in two launches, or launch it as an empty shell and use the second launch to furnish it; actually, do that, it's more awesome and gets more done), fuel the craft and send it to EML1. There, fuel it up again and execute a slingshot around Terra, sending our 300 tonne ship with it's landers on a 3 month trip to Mars.
Wait, before we do that, send a big mining probe to produce fuel for the landers and the return journey from Phobos, if there's ice there, and from the surface if there isn't.
Anyway, 3 months later our crew of 12 arrive...
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Before the West started working with Russia, NASA considered "Heavy Lift" to be something on the order of a Saturn V. A Saturn 1B was considered "Medium Lift". That was able to lift 21,000kg to LEO. That's about the same as a Russian Proton rocket. But Russia called Proton "Heavy Lift". So Boeing started calling their Delta IV and Lockheed-Martin their Atlas V "Heavy". Their engineers called the version of these rockets with a single core module "Medium", but the version with 3 core modules "Heavy". But those "Heavy" versions were no where near a Saturn V. Now their sales people call even the single core modules "Heavy". Need I say anything more about sales people?
Russia called Proton "Heavy", and Energia "Super Heavy". Even the Russians have difficulty using the word "Heavy" for the 3 core module versions of EELVs. I consider the new proposed SpaceX rocket "Heavy", but to use the Russian terms it would be "Super Heavy".
As for lunar fuel, have you read "The Case for Mars"? Lunar fuel is not at all useful. The Moon is a valid destination itself for science, but there's no fuel there, and any attempt to harvest oxygen will consume more resources than it produces. Your better off launching for Mars directly from Earth orbit.
Energia was able to lift 88 metric tonnes to 200km orbit at 51.6° inclination (passing over Baikonur). That's without its upper stage. An aerospace engineer in Canada, an immigrant from Ukraine who was educated in Russia, told me that with its upper stage, Energia lift 120 metric tonnes to LEO. I don't know if that's 185km orbit, the usual altitude that American rocket manufacturers use for their statistics. I could look it up when I get home.
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As for Lunar fuel, Robert Dyck, have you been keeping up with recent discoveries? Ice is not that hard to turn into Oxygen and Hydrogen, and the poles have lots of ice available. You're better of launching to Mars from the Lunar L1 point.
So, this launcher would launch much more than Energia? Mmmm. I wonder if we could man rate the launcher and use it for lofting colonists, 100 at a time. That would cost maybe $3 million per person.
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Water on the Moon is probably best left ON the Moon, for use by scientists going there.
Water in passing asteroids has no higher benefit use, however -- fair game to harvest those and probably no more expensive, all things considered.
[color=darkred][b]~~Bryan[/b][/color]
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Scientists don't need 600 million tonnes of the stuff. By the time we need that much, we can import it cheaply from elsewhere.
Saying that we should leave it for the colonists makes as much sense as saying that we should leave hydrogen and oxygen on Terra for use by the people here, rather than wasting it in rockets.
Anyway, what about the rocket?
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As for Lunar fuel, Robert Dyck, have you been keeping up with recent discoveries? Ice is not that hard to turn into Oxygen and Hydrogen, and the poles have lots of ice available.
I have. Lunar Prospector found no chunks of ice what so ever. It did find hydrogen, which could be ice crystals the size of a grain of salt, or could be hydrated minerals such as clay or gypsum. It's believed the source is meteors and asteroids, so material from a carbonaceous chondrite asteroid is entirely possible. If it is ice, then the richest deposits have one cup of water over an area the size of a football field. But some scientists didn't want to accept that, so challenged the instruments. Odd, considering it's the same instrument that was on Mars Odyssey, the same instrument that measured hydrogen in the top metre of Mars soil. That has since been confirmed by ground penetrating radar on Mars Express and MRO, as well as Phenix, Sprit, Opportunity, and now Curiosity. But the lunar data was challenged, so NASA sent LCROSS. It impacted the greatest concentration found by Lunar Prospector. It found 100kg of water in 30 million kg of regolith. That's 3 parts per million. And again, that's the richest concentration on the Moon. Equipment to harvest that water would weigh more than any water you would collect. That's without taking into account cost, or energy to operate the equipment. So no, there isn't lots of ice.
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Erm, yes there is. Do remember Lunar Prospector was a mission that ended 14 years ago. It is by no means recent research.
http://nssdc.gsfc.nasa.gov/planetary/ice/ice_moon.html
"Analysis of the results indicates concentrations of roughly 6% water in the impact area, including nearly pure ice crystals in some spots. The Indian Chandrayaan-1 Moon Mineralogy Mapper experiment showed low-concentration hydroxyl signatures over much of the lunar surface, not just in permanently shadowed craters (2), and the Mini-SAR experiment indicated possible large deposits of water-ice in the northern lunar craters (3). "
6% is not "3 parts per million".
It's just some people don't want to accept that building up Lunar infrastructure, rather than heading to Mars directly, makes sense.
Anyway, this thread went off topic quickly...
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LCROSS was 2009.
http://lcross.arc.nasa.gov/
At the time they announced 100kg of water ice was thrown up. But they refused to say how much regolith was thrown up with it. Robert Zubrin estimated regolith, he came up with 30 million kg. So that's 3ppm. The web page you link claims 6%. That isn't consistent with official science results.
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The web page I link is from the space agency that was responsible for the mission in question...
That's not the only evidence we have. The Indian orbiter found quite significant indicators of thick ice sheets.
Google "ice at the lunar poles", and you'll turn up lots of websites (official and not) and articles claiming that there's ice there, and none claiming that there isn't. One lone guy without access to all the data and with a vested interest in keeping people away from Luna does not strike me as a reliable source...
Last edited by Terraformer (2013-04-10 06:08:20)
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Zubrin = "vested interest in keeping people away from Mars"?
I thought he was the Mars Direct guy ....?
[color=darkred][b]~~Bryan[/b][/color]
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On a lighter note .... what are the theories as to why the water would be more concentrated at the lunar poles? Did the ice comets just happen to crash there? Or did the lunar gravity pull them there? Or did a gaseous volatile meteor strike give the Moon a brief atmosphere and allow the water to gather at the poles and freeze out in a cap, like Mars?
On Mars, the very presence of water ice caps on the poles is prima facie evidence of the warmer wetter Mars of the past -- it had to be airborne as vapour and carried there by weather patterns away from a past temperate zone in order to freeze out on the caps.
[color=darkred][b]~~Bryan[/b][/color]
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My mistake. I meant to say Luna.
If he wants to, he can pay to have his share of the fuel hauled from Terra rather than taking advantage of the depot. It will quadruple his rip costs, but hey, if he wants that...
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The theory is that comets and carbonaceous chondrite asteroids hit the Moon everywhere. But where sunlight shines, water boils to steam. Surface temperature can get up to +123°C during the day, but -153°C at night. The Moon has 2 weeks of daylight, then 2 weeks of night. That boils then re-freezes water. Each time it boils, some water will escape the Moons gravity into space. But if water re-freezes at the bottom of a crater at the poles where sunlight never touches it, then the ice will remain permanently. So polar craters are cold traps.
As for large chunks of ice, Lunar Prospector had a neutron spectrometer and gamma ray spectrometer. That's the same instrument that Mars Odyssey used to measure hydrogen in the top metre of Mars soil. Large chunks of ice will absorb high speed neutrons, causing a dip in neutron emissions from the Moon. Lunar Prospector did not detect any such dip. That means no large chunks of ice. None. Not at all. Nothing. Period.
This makes sense. When asteroids hit, they will boil off any water. When it re-freezes, expect tiny crystals. Snow flakes won't grow like on Earth because no air. Expect re-freezing steam will form crystals far too small to be detected by the high speed neutron spectrometer. The epithermal neutron spectrometer did detect a dip in emissions. Those neutrons are absorbed by any hydrogen, not just large chunks of ice.
Free neutrons do not survive long enough to make the trip from the Sun, any neutrons will decay to protons before they reach Mercury. So solar wind has plenty of proton radiation, but no neutron radiation. When solar wind impacts the Moon, there's no magnetic field or atmosphere to stop it, so it hits the surface. When solar wind (proton and heavier radiation particles) hits the lunar surface, some neutron radiation is created. Since neutron radiation will not survive long enough to come from the Sun or any other planet, that means it's coming from the body the probe is orbiting. This uses the Sun's radiation itself as the energy source to scan the surface of the Moon or Mars. Solar radiation will only penetrate 1 metre depth, so what you get is reflected radiation from everything in that 1 metre. It won't tell you what's deeper underground, or what is at any specific depth. The radiation is a mix of every in that 1 metre of soil and rock.
Some people have speculated that ice "might" be in concentrated pockets rather than evenly spread. But I told you how it gets there. That means evenly spread frost and snow-like ice crystals. There isn't any evidence of concentrated pockets, and the theory precludes it. Rather it's evenly spread at the bottom of craters so deep that sunlight never touches them.
Robert Zubrin is an aerospace engineer. He calculated that if space aliens had left depots of fuel waiting on the Moon, so no mining or refining was required, it would still cost more to get it for a Mars mission than direct launch from the surface of Earth to Mars. Of course he also argued (strongly) to not build any space station. We have the station now, so I've argued to use it. And he argued for human exploration of Mars instead of unmanned probes. I've argued we've already sent the probes so that argument is now moot. Since we have so much data from unmanned probes, we can already choose a location for a permanent base. So start building that base with the first human mission. But none of that changes the physics of trying to bring anything from the Moon.
I'll throw you a bone. There isn't enough water on the Moon to produce fuel. That's long since determined. Wishful thinking won't change that. But "Lunar Soil Propellant" is powdered aluminum with liquid oxygen. There's plenty of rock on the Moon. You can smelt that to make aluminum. It would take a lot of processing to smelt aluminum from feldspar, either anorthite or bytownite, but it is possible. It's already been demonstrated you can mix them in a single tank to form monopropellant. Is that safe? That's another question.
Last edited by RobertDyck (2013-04-10 16:44:04)
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Yet again, you reject what everyone else is fairly confident of.
Robert Zubrin seems to think that the idea is to go to Luna and then go to Mars Directly from Mars, because Robert Zubrin has a nasty habit of using strawman arguments. I believe it was Hop who posted about the absurdity that mining petroleum in Texas is absurd if you want to go from New York to Boston, or something along those lines, if one uses the same reasoning that Zubrin does.
Anyway, this really ought to be in the thread about fuel depots...
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Hey, I would like a fuel depot in Earth orbit. We could harvest fuel from a carbonaceous chondrite Near Earth Asteroid (NEA). You can get oxygen from lunar regolith as a by-product of smelting. There are plenty of metals: aluminum, iron, titanium. And of course lots of silicon because there's lots of rock. But no carbon, and too little water to be worth harvesting.
And helium-3 is another Moon idea that has been debunked, but Moon fans don't want to listen. Currently there is no fusion technology that produces more power than it consumes. A couple experimental reactors achieved break-even for a fraction of a second, but over a multi-hour or multi-day period even they consume more power than they produce. But once we achieve stable fusion, then heat from a deuterium/tritium fuel mixture to increase temperature even further to achieve double-deuterium fusion. That allows nothing but deuterium for fuel. Deuterium is in every drop of water on Earth. Ask any businessman: would he spend the billions of dollars to harvest helium-3 from Luna, or just consume more tap water? Deuterium from tap water. Any businessman would say more tap water. So helium-3 for fusion will never be an economically viable export from the Moon.
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Getting back to the point of this thread, the Saturn V had various design variants. The C5 was used to send men to the Moon. It was rated to lift 127,000kg to LEO. Another document states 118,000kg to 185km @ 28° inclination (over KSC). I'm not sure if the difference is launch vehicle configuration, or orbital altitude. In any case, it's rated for 47,000kg to a trans-Lunar trajectory, or 45,000kg to escape Earth all together.
The web page you linked said SpaceX expects to get Falcon 9 Heavy ready this year, able to lift 53t (53,000kg) to LEO. That's just Falcon 9 rockets bolted together. The new rocket would lift 150-200t to LEO, to eclipse SLS. And it says SLS will lift 130t to LEO. That makes SLS equal to a Saturn V, and the proposed SpaceX rocket even larger.
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If the new rocket can throw the same fraction to trans-Lunar trajectory and escape, then that's about 55 tonnes towards Luna, and 53 tonnes to escape (so, I'll concede that Mars Direct could be done fine with it - not that I think that's an efficient use of resources) if it's 150 tonnes to LEO. If it's 200 tonnes to LEO, that's 74 tonnes and 70 tonnes respectively (all figures are rounded down). I don't know if rockets are more efficient today, in which case we could throw even more...
That's... a lot...
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My understanding is that the engines in the Grasshopper are supposed to be significantly more effective than previous.
I see that the site is quiet. A large part of me wants to stop corresponding. I can see that I have my footprint all over the place, and in fact I really don't want to bogart (American local thing) the place.
However, following your reference to the Moon, and apparent affinity for the Moon, I implore you to consider certain thoughts that I have to offer.
We have to work within the constraints of what Nasa will do or SpaceX, and they are responding to social and financial pressures that they cannot ignore.
Here are some links:
http://www.space.com/20609-nuclear-fusi … -mars.html
http://io9.com/5908499/could-helium+3-r … y-problems
(I really think that the above article is too negative. I don't think you have to heat the regolith, but rather expose it to a microwave energy tuned to Helium 3, so as to make it mobile. Maybe I am wrong, but I think that would loosen some of it. Then you would be able to try to capture it with ionic processes and electrostatic force).
http://www.space.com/20612-nasa-asteroi … ained.html
Have you considered Helium 3? Granted there is much more water associated with the Moon than the Apollo era supposed, and there is no reason to not try to utilize that. But if the 2nd link could prove true, my understanding is that a fusion fuel is available on the Moon, that could open up Mars to 30 to 90 day missions.
I have included the 3rd link because we also have to factor in the fact that it might be possible to extract propellants and structural materials from small asteroids that can be moved into L1-2-3-4-5 locations about the Moon.
I would say being flexible is a good plan. All of this might fit together into a master plan. Perhaps water from the Moon used to loft Helium 3 into low lunar orbit, and propellants from small captured asteroids to get it up to higher orbits (L#). And Fusion of Helium3 and/or Helium 3-Tritrium to get a fast and powerful ride to Mars.
I really hope I am not driving others away from this web site, that is not my intention.
Last edited by Void (2013-04-10 22:17:43)
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That would be good - if we had fusion rockets...
Though, Helium-3 is pretty valuable at the moment, even without fusion. It costs, what, $500-1000/g, so a kilogram of the stuff could retail for $500k. Though I don't think we could base a Lunar economy on that, since we'd probably crash the market...
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Grasshopper uses one Merlin-1D engine, which has a higher engine thrust/weight than the Merlin-1C engines powering Falcon-9 right now. Merlin-1D will be flown soon on Falcon-9, upping its 28-degree LEO payload out of Canaveral to 13 tons from the current 10 tons. The 53 ton capability of Falcon-Heavy is, and always has been, predicated up Merlin-1D's. (Metric tons.) That's based on their website.
I dunno what good Helium-3 is right now, or why it might be valuable right now, since there are no fusion reactors or fusion rockets to use it. Once there are, I understand that it could be a good fusion fuel. But those technologies still appear to be a good ways off, controlled fusion being "just around the corner" since the mid-1950's. Not a good trend, that. We're gonna need a breakthrough.
GW
Last edited by GW Johnson (2013-04-11 14:46:53)
GW Johnson
McGregor, Texas
"There is nothing as expensive as a dead crew, especially one dead from a bad management decision"
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I hear you.
However I always like to keep the door to the future open a crack.
I am not surprised at your post, since your scope seems to be "Get a mission to Mars", which is not wrong at all.
I like to look at the short (Which is actually a very big thing) to get such a first mission to Mars, and the Medium and the long.
I also like to try to conciliate the tribes, the Marsies, the Lunies, the Asteroidies. Why not see if everyone can be on the same team in some way? In the long run, odds are it will be for the better.
Some of these groups are going to do what they do anyway. Go for Asteroids, the Moon, Mars Flyby, and National entities will try for Mars. An attempt at a master plan might be able to integrate at least part of these into some type of mutual support which could be useful.
Just now I am pondering if there is any way to integrate the Mars flyby idea with some type of Phobos sample return. In this case, I think I likely will come up empty, but it is worth pondering just a bit more.
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I just thought I would add this about "Limited" fusion process in some Brown Dwarf Stars:
http://en.wikipedia.org/wiki/Brown_dwarf
Brown dwarfs are substellar objects too low in mass to sustain hydrogen-1 fusion reactions in their cores, unlike main-sequence stars, which can. They occupy the mass range between the heaviest gas giants and the lightest stars, with an upper limit around 75[1] to 80 Jupiter masses (MJ). Brown dwarfs heavier than about 13 MJ are thought to fuse deuterium and those above ~65 MJ, fuse lithium as well.[2]
I guess nobody is thinking about human created hydrogen-1 fusion, but deuterium fusion typically, and also there has been speculation about using Helium 3 as an additive.
The statement that a 13 M Brown Dwarf can fuse deuterium, but a 65+ M can fuse lithium (But not hydrogen-1), implies to me that if you can kickstart a deuterium (Or Helium 3 mix), and then cause a Lithium fusion, there could be some significant additional power there.
If I am not mistaken, fusion burns are a reality in laboratory settings now, and since your process objective would not be to harness energy as electricity, perhaps a fusion rocket thrust were a small match can be lit to ignite a lithium fusion reaction to propel a rocket might make more sense (And be more reachable) then trying to compete with coal power here on Earth with a fusion power plant using non-Lithium and non-Hydrogen-1 fuels.
My intuition suggests to me that in their process where not only magnetic forces are used, but the inertia of solid lithium, and where you do not regard the burning of the walls of the confinement by plasma to be a problem (The lithium), but a part of the process, then you have greatly reduced the constraints on success, the requirements of control by magnetism.
As for saturating the HE3 market on Earth, I would speculate that that could happen, but if He3 from the Moon facilitated fast trips by miners, and some of their equipment to asteroids holding valuable metals, and propellants, the Helium 3 would translate into profit, by making those materials economically available.
I am going to check how much lithium there might be on the Moon It is more made of lighter but not too light things.
Well, this will do. It is there, don't know how hard to extract, but likely can be:
http://rsta.royalsocietypublishing.org/ … 85/1327/49
I suppose maybe the asteroids, also, but who can say what works best later?
Last edited by Void (2013-04-12 15:08:14)
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This was the in between state for getting to BFR with the Raptor engines and Space x canned it instead...
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