zaterdag 21 december 2013

Lunar resources and a new Space Race

With the successful landing of Chang'e 3, the attention of the world's spaceflight enthusiasts and experts alike once again turns towards the moon. These things spawn up discussions about why we should go to the moon, whether there is economical benefit to it, or about the "new space race", as well as the usual complaining about NASA's lack of productivity or that those damn commies is taking muh spaceflight.

And to be honest, when these things happen, I can't help but feel a slight annoyance. Many of these things are based upon false premises, or people who live in the 1960's, or general ignorance of spaceflight that results in xenophobia, anti-americanism, armchair experts (I'm being a little bit of a hypocrite here, I'll admit that) schooling others like it's their job and nationalist slapfights. 


Lunar resources

Something I've seen so many times lately is that we can use lunar resources to pay off our debt, make fusion attainable, makes spaceflight more sustainable and many more things. But is this really true? Can lunar resources make the moon an economically viable source for materials needed on Earth? I don't think so. Let me show you this with an example.

Say we assume the cheapest LV in terms of cost/kg currently available in the near future, Falcon heavy. With ~2500 $/kg, this vehicle could get 53 metric tons into LEO with a cost of $135 million. The ∆V needed to return from the lunar surface is 3 km/s. A 53 ton stage with a 0.87 PMF (realistic since there have to be legs and everything attached to the stage) could get about ~35 tonnes back to Earth. This stage would land on the moon, be refueled there, and could be sent back. So how much would this cost?

The cost of this material would be $3900 per kg. But it gets worse. This assumes that the entire payload is nothing but the actual material. If you put it in a container, it becomes more expensive. Something like a Dragon capsule can return 3/4 of it's own mass back down to the surface, or 3/7 of total mass. Suddenly, you're looking at 4 tons returned to Earth, and a cost of $9000/kg. And in the case of a low density material like Helium 3, you get even lower return down to the surface. 

To make things even better, this assumes that the base put there was entirely free and that the stage could be refueled there for free. If you don't assume refueling there's no payload at all, and if you take into account the cost of a lunar mining base, which is on the order of $100 billion, you'll quickly see why lunar mining isn't very economical currently. This also assumed the cheapest vehicle to LEO available in the near future; if you went with Delta IV it would cost 6 times as much.

So, lunar resources are, for the time being, a pie in the sky dream. They are extremely expensive to get back and the ROI would take so long (if there was any profit at all) that it simply isn't worth it for a long, long time. I'm not saying they can't be useful, a prop depot in lunar orbit or a small refueling base could really ease up lunar exploration. I don't think it should be held like a good reason to go there. If lunar resources are to be seriously considered as a reason for lunar exploration, we should first get launch costs down by one or two orders of magnitude before it is a serious argument in favour of lunar resources for use on earth.

And Helium-3... How about we perfect Tritium-Deuterium fusion before we go there to pick it up? And there's always Proton-Boron fusion if neutron-less fusion is so important. It's not really necessary for attainable fusion.

A new Space Race and China's space dominance

By far my favorite. Go on any thread on reddit related to China's space program and you'll find a bunch of people preaching about the new space race, that the US should step up their game because the Chinese are overtaking "us", etc. And I usually just sit there laughing or being slightly frustrated with this.

First, why a new space race? There certainly are no signs of one. China is stepping up their game but neither the US nor Russia show any sign of doing the same. Their plans have changed little regarding exploration; the US still has to work in the direction of an asteroid, and Russia still works in the direction of the moon and Lagrange points. There is no space race going on at the moment.

What surprises me even more are all the people who wish for a new space race. And I flat out don't get it. What happened the last time we had one? The US landed on the moon. The costs, which were so high in part because of time pressure, sent Congress and the administration into shell shock.  Apollo applications was canceled and a "cheaper" LV, the space shuttle, was signed into law. That "cheap" LV got the US stuck into orbit for 30 years. Apollo was expensive, accomplished little and forced NASA into the terrible position it was in for the past few decades, until it was decided to finally axe the shuttle in favor of a conventional rocket with a normal capsule. A safer, more affordable and more flexible vehicle. Alright, Orion and Ares 1 are a bad example. Falcon 9 and Dragon, or Atlas V with CST-100 are better examples. Still, the last space race got us stuck for a long time. 

A new space race would get NASA to the surface of the moon, maybe Mars, for a few times. We would alienate a potential spaceflight partner, would cause NASA to create an expensive and unsustainable program similar to CxP, only to cause massive budget cuts once the program is over and we'll never go anywhere for many years afterwards. The other option is teaming up with China/Russia/whatever dirty commie country 'Murica is afraid of for no reason/ESA and spread costs and effort over several different nations, allowing large scale exploration for much lower cost in a more sustainable way. Which one do you think will result in more stuff getting done? 

Second thing is, why are people so afraid of China? As reddit user Ambiwlans so eloquently put it, "Since Russia collapsed all the people that need a bad guy to fear seem to have latched on to China." Since there is no big scary red Russia to fear, people start irrationally fearing the other "big scary commie country" out there, which is China. But is China really that big of a danger to the US space "dominance"? Let's compare the two, shall we:

China:
Biggest LV: Long March 2F/G, 11.2 tons into LEO. 25 ton launcher in the works.
One crewed spacecraft, three crew, a few days on orbit life time. No new one in the works.
Budget $1.3 billion

US:
Biggest LV: Delta IV Heavy, 28.8 tons to LEO. 53 and 70 ton launchers in the works.
No crewed spacecraft, but four in the works. One can support crew of four for three weeks.  
Budget $16.8 billion

So yeah. Another big red scare that really isn't that scary. China is not yet capable of doing anything the US hasn't long been able to do, and they don't have the means to do anything significant for the time being. They have a focus, which is a big improvement over what the US has. But should the next administration of the US decide to switch focus, all that has to be done is developing a lunar lander and the US could be back on the moon by 2025. China isn't even trying to land earlier than that. Older articles claim 2017 but these are usually very outdated.


"NASA should get off their arse and do something productive, they don't do anything unlike China"

Let me just answer with a few pictures. 

Curiosity is a lot cooler than Yutu.







Cassini, currently orbiting Saturn
New Horizons spacecraft, currently underway to Pluto
SLS tank barrels being manufactured right now
Dragon spacecraft, funded and co-developed by NASA

9 opmerkingen:

  1. 1. While the leadership in America is mostly dominated by cynical lawyers, the leadership in China is mostly dominated by scientist and engineers. China is thinking decades ahead-- not just a few years ahead

    2. The first nation to establish a self sustaining industrial colony on the Moon will dominate the satellite manufacturing and launch industry because of the Moon's enormous gravity well advantage over the Earth. Satellites are currently at the core of a $200 billion a year satellite based telecommunications industry.

    3. Clean energy for the Earth could be supplied directly from the Moon from solar power plants or even nuclear power plants

    4. Some regions of the Moon are rich in thorium. Exporting thorium enriched up to 1% with fissile uranium 233 could be exported from the Moon to Earth for use in nuclear power plants on Earth

    5. The US NAVY has already invented the portable electric gun that could launch material off the surface of the Moon. If this terrestrial weapon were used to launch lunar material into orbit, light sails that use no fuel at all could hurl that material into Earth orbit. Space planes that fly home empty could return with lunar materials such as enriched thorium.

    6. The first nation to have a reliable lunar transport system that could allow people to travel round trip to the Moon for less than $50 million per ticket could dominate the emerging space tourism business. Their are currently 14,000 people in the world worth more than $250 million. Just 50 super wealthy individuals traveling to the Moon every year would be a multi-billion dollar a year industry.

    Marcel F. Williams

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    1. 1. This is mostly true. However, China's ambitions quite obviously also have political motives, and I doubt it's as black and white as that.

      2. That satellite business is mostly from commercial companies. A self-sustaining moon base would be state-run; there is no near-term return of investment so few commercial entities would want to invest in that. Commercial companies would likely want to keep their satellite manufacturing business down on Earth. Think about it, it wouldn't be very efficient to ship groups of workers and materials to the moon, which takes far more than just going to GTO, only to launch spacecraft from there for slightly less.

      3. There is no reason to put this on the moon instead of in orbit or down on Earth. Any potential saving from higher efficiency is completely minimal compared to the massive costs of assembling and maintaining such a facility in orbit.

      Elon Musk has said he wants to stab space-based solar power in the heart, and he's bloody right. It doesn't work, it's inefficient, it's expensive and there really is no reason why we couldn't do it much more cheaply and efficiently down on Earth. Nuclear, I don't even know why that would have to be space based. We have it on earth, it works fine, and newer generations of nuclear are even safer than the ones we currently have, which have only failed us once because of a tsunami.

      4. Thorium is common on Earth, there is no reason to take it from the moon.

      5. That's an interesting concept and I'll admit that I can't argue against it.

      6. Can't really argue against that either, although I doubt it would be very profitable.

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    2. May I add something to point 5? It might be an idea to send lunar resources to Earth using magnets. Couldn't we build something that works with MagLev that propels containers with resources, thanks to the moon's low gravity and lack of atmosphere, to Earth? You could launched them on certain points in the moon's orbit so that they'll land around a place where you can easily retrieve it.

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  2. " They are extremely expensive to get back and the ROI would take so long (if there was any profit at all) that it simply isn't worth it for a long, long time."

    Fortunately, getting raw materials off lunar surface does not require rocket propulsion, which throws your entire calculation out of the window.
    Also, not everything is supposed to be profitable within 3-5 year investor time window, some things take long time to pay back.

    Funny that you can open a 12 year old bottle of whiskey ?

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    1. How else do you want to do it? A cannon? Won't allow for global lunar access. Setting up the network to move it around the moon will cost you decades and trillions.

      There won't be a return of investment for 5 years, there won't even be one in 12 years, it will take decades or even centuries and hundreds of billions of dollars. This isn't making a bottle of whiskey.

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  3. A satellite manufacturing and launching facility on the lunar surface would require more than a government Moon base. It would require a lunar colony probably numbering in the thousands-- even though a lot of the work could probably be done by people on Earth utilizing tele-operated robots.

    But the US government really doesn't manufacture anything. Private industry does. Private factories on the Moon, within government licensed territories, for manufacturing and launching satellites could be up an running by the 2040s or 2050s, IMO.

    Marcel

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  4. Launching the few dozen satellites for slightly less is not a good reason for setting up a colony with thousands of inhabitants.

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  5. Thanks for the calculation. However, I can give a heuristic argument that a mineral processing plant on the Moon would cost far less than $100 billion. Such estimates are based on what the Apollo program cost, or the Constellation program would have cost.
    But that was based on including the huge development costs for the large HLV launcher and all the individual components from scratch. However, we're assuming the development of the launcher, the Falcon Heavy, will be paid for by SpaceX itself. That takes off a really large component of the development cost.
    Remember also all the various in space stages could be taken from all the already developed stages we have available now which again takes off a large amount from the development cost. During Apollo remember all these stages had to be developed from scratch since it was still in the early days or orbital rockets.
    Now the delta-v to the lunar surface is about 6 km/s from LEO. A high efficiency Centaur-like stage can get about its own fueled mass in payload to 3 km/s. So about 1/2 the total mass would be payload to 3 km/s. Then by using staging about 1/2 again, or 1/4th, the total mass would be needed to get to the 6 km/s needed for lunar landing. So taking the cost to LEO by the Falcon Heavy as $2,500 per kg, the cost to the lunar surface would be in the range of $10,000 per kg, assuming smaller costs for the much smaller in space stages than the Falcon Heavy itself.
    Then if you were to take a $100 billion cost to set up a processing plant on the Moon, since the plant itself would cost far less than that even if it were say $1 billion, you would be saying the launch cost to the Moon would be in the range of $100 billion. But this would be saying the mass of the processing plant would be in the range of 10,000,000 kg. Clearly it would not have to be anything near that. For instance there exist small *portable* processing assemblies for purifying gold ore.


    Bob Clark

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  6. I didn't say that a colony on the Moon should be set up to manufacture and launch satellites. I said that an-- already established-- colony on the Moon would dominate the satellite manufacturing and launching of satellites.

    The first true colonies on the Moon (thousands of people) will probably grow gradually as the result of space tourism to the lunar surface probably starting in the late 2020's IMO. There are 14,000 people on Earth worth more than 250 million dollars. By the time lunar tourism starts, the cost of traveling to the Moon could be less than $50 million per individual if reusable lunar shuttles and orbital transfer vehicles are utilized. And those prices are likely to drop dramatically if at least 100 wealthy people or lunar lotto winners a year travel to the lunar surface.

    Human space flight is expensive because there is so little demand for it. But once hundreds of people are traveling into space on an annual basis then prices are going to fall dramatically and soon thousands will be traveling into space causing prices to decline even more dramatically.

    Marcel

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