All Astronautical Evolution posts in 2017:
What is a Supercivilisation? (Aug.)
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Short story The Marchioness
2016: Stragegic goal for manned spaceflight…
2015: The Pluto Controversy, Mars, SETI…
2014: Skylon, the Great Space Debate, exponential growth, the Fermi “paradox”…
2013: Manned spaceflight, sustainability, the Singularity, Voyager 1, philosophy, ET…
2012: Bulgakov vs. Clarke, starships, the Doomsday Argument…
2011: Manned spaceflight, evolution, worldships, battle for the future…
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Building Selenopolis (2008)
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Five Principles of a Sustainable Manned Mars Programme
Note: this blog post has been amended and corrected since it first appeared.
An expanded version has now been published in Spaceflight magazine,
Sept. 2017, p.336-342.
Lockheed Martin’s plan
I recently made a contribution to issue 10 of the space journal Room, thanks to an invitation from its editor Clive Simpson. Right after my own article comes a report by six Lockheed Martin executives entitled “Blueprint for NASA’s journey to Mars”, describing their company’s Mars Base Camp concept.
Room, by the way, started publication only a couple of years ago, and is extremely well designed and produced. Although published in Vienna, all the text is in English.
Anyway, reading that Lockheed Martin article got me thinking about how I might draw up my own blueprint. What are the fundamental principles that one would want to follow in order to make a success of a humans to Mars programme? How might one score competing proposals? I have identified five key points.
(1) Extraterrestrial propellant manufacture
In his famous 2011 Keynote Speech, Jeff Greason emphasised the need to “make gas” at each extraterrestrial destination we reach. There are in fact several options:
The importance of “making gas” can hardly be overstated. The large amounts of rocket propellant required to go anywhere in the Solar System for any purpose mandate a refuelling industry independent of Earth as soon as possible.
(2) Extraterrestrial food production
Current manned Mars plans propose to feed the crew with rations packed on Earth; this is obviously unacceptable for any but the most fleeting of visits. A serious Mars programme will need to get to grips with extraterrestrial food production, as well as full recycling of water and oxygen from human biological wastes, both to avoid a Mark Watney situation (as in the novel and movie The Martian by Andy Weir) and to enable long-term growth.
Clearly, local food production with full recycling of human wastes would be the first step in a process which would extend local self-sufficiency to manufacture of cleaning materials, clothing, drugs, furniture, machinery, electronics and ultimately the full range of products available on Earth.
(3) Artificial gravity on the Earth-Mars cruise
Given the problems astronauts have had adapting to weightlessness, with at least two hours a day of exercise essential for their health, this is a no-brainer. Zubrin’s Mars Direct architecture adopts it as a matter of course. Three further points are of particular weight here:
Therefore experience with partial gravity space stations in the Earth-Moon system will come before a manned flight to Mars in any case, so the mission architecture might as well use the technology to generate whatever level of artificial gravity is found to provide an effective antidote to the stress of microgravity on the long (6 months or more) interplanetery transfer.
(4) Hardware commonality for both exploration and commercial use
Another of Jeff Greason’s points was that each capability gained by the space agency must be designed for transition to the private sector when technologically mature, since only in that way is it possible to add new capabilities at constant budget.
The converse is equally attractive: space agencies should improve their capabilities by using technology already developed for commercial purposes. The historical record provides examples of this pattern, for example with commercial ships being used for ocean exploration, and with commercial aircraft being used to access Antarctica. For example, the first aircraft to land at the South Pole, in 1956, was a US Navy adaptation of the famous DC-3.
Of course it may well be that space agency officials and governments want to press ahead with a Mars orbiting or landing mission when the technical heritage they need is not yet there, and so end up losing the mutually beneficial coordination with the development of commercial services. That’s their choice.
(5) Create safe havens wherever possible along the way
It need hardly be stated that the first explorers of Mars will be cut off from all the resources of civilisation in an unremittingly hostile environment to a greater degree than any explorers ever before in history.
Of course, if one corrects for contemporary technology and knowledge, they will in many respects be better off than were the explorers of the world’s oceans in the age of sail. It’s an interesting coincidence that a round trip to Mars would last approximately the same time as Drake’s circumnavigation of the world from December 1577 to September 1580.
Be that as it may, one wishes to avoid the attrition of ships and men suffered by Magellan, Drake, Anson and others. The way to achieve this is to accumulate reserves of propellants, consumables, spare parts and radiation shielding at strategic points along the way. The programme needs to focus on setting up a permanent and growing extraterrestrial infrastructure:
Clearly, full advantage should be taken of the capability to build infrastructure robotically prior to human occupation.
Designing for growth
What after all is the overall purpose of a humans to Mars programme? It boils down to the choice posed by John Marburger in his 2006 Keynote Address: “whether we want to incorporate the Solar System in our economic sphere, or not”.
Since the benefits of doing so include safeguarding the long-term future of our civilisation and our species, maintaining the culture of growth and progress critical to our society’s success without unduly overburdening planet Earth, and developing humanity’s creative potential to its maximum extent, and since the benefits of not doing so are negligible except when seen through the lens of a highly distorted vision of mankind’s place in the universe, I take it that the answer has to be that we do.
Therefore space systems need to be capable of growth:
That last point has the corollary that peaceful, sustainable development must continue on Earth itself, for everything we do in space will depend on Earth’s continued prosperity for centuries to come. Furthermore, the overwhelming majority of the human population will continue to live on Earth for the next thousand years or so. If after that period they are outweighed by the numbers living off the mother planet, it will be because of extraterrestrial growth, not terrestrial decline.
People sometimes argue – the popular cliché! – that we should not be spending an effort to explore or colonise Mars when there are still so many problems on Earth. This is too simplistic, based on household economics where one has ten pounds in one’s pocket and is trying to decide whether to spend it on green vegetables or chocolate. The choice at the level of national economies is different: whether to encourage a dynamic, growing, problem-solving society, or to suppress it. If the former, then some entrepreneurs will develop life on Mars, others will do so on Earth.
As the Americans would say: we can walk and chew gum at the same time.
The foregoing is, of course, a restatement of the ideas of the Astronist Mars Strategy from a couple of years back.
The reorganising of those ideas into five basic principles here is to help focus on specific mission architectures. So how do the current crop of Mars designs measure up?
Robert Zubrin’s Mars Direct, first presented 27 years ago (on 20 April 1990 at the Marshall Space Flight Center in Huntsville, Alabama), made a quantum leap forward by introducing the first practical scheme for propellant manufacture on Mars. It uses artificial gravity on the interplanetary cruise, builds up a safe haven on the martian surface and devotes considerable attention to building up local self-sufficiency with local resources.
Zubrin’s vision of martian food production is, however, based entirely on conventional crops (possibly related to the fact that he is keen to emphasise the superiority of Mars for crop-growing in comparison with the Moon). I would therefore give him only half a point for extraterrestrial food production.
Although Zubrin goes on to discuss the growth of a martian civilisation, he remains vague on the process by which government missions could metamorphose into commercially self-sustaining ones, and the major omission in his book is any mention of how his space agency Mars rockets and spacecraft would share costs and markets with commercial activities such as space tourism and orbital manufacturing. Without such sharing, they would quickly go the way of the Saturn V and Apollo vehicles when the government lost interest.
I would therefore give him 3½ out of 5, which is a still high bar for more recent plans to match.
The Elon Musk/SpaceX plan was announced in some detail at the International Astronautical Congress in Mexico on 27 September last year, as I reported earlier. Given the nature of the company, I think we can be sure that any Mars vehicles it builds will be fully exploited for their commercial potential, even though Musk did not explicitly say this. It’s also clear that he would quickly build a safe haven on the martian surface as the nucleus of a colony specifically designed for growth towards self-sufficiency. His plan also embraces martian propellant production from local resources.
Musk’s own four key elements for success are in fact all focused on transport: full reusability of vehicles, refuelling in orbit through tanker flights, propellant production on Mars, and choosing the right propellant (methane/oxygen). But he has so far omitted to consider important human factors. Although local production and recycling are implicit in his goals, he did not say anything explicit on the subject, so for local food production I can only give him half a point.
He has not recognised the major difficulties that still stand in the way of setting up a full biosphere independent of Earth and able to support a human colony. Musk’s vehicle design furthermore suffers from the lack of provision of artificial gravity on the interplanetary crossings, despite looking ahead to even longer flights from Earth as far as the Jupiter and Saturn systems.
His resulting score: 3½ out of 5, matching, but not surpassing, Mars Direct.
Finally, Lockheed Martin’s Mars Base Camp concept was what inspired this post in the first place. Despite the name, the base camp they have in mind is a station in a highly elliptical geosynchronous Mars orbit. Most of the station doubles as the interplanetary transport craft, with just a laboratory and a space tug being pre-positioned (using solar-electric propulsion) and then left behind at the end of the mission for future use, together with a number of remotely operated rovers and aerial vehicles on the surface. There is certainly no sense of a safe haven being cumulatively built up with any greater capabilities than the transport vehicles themselves.
In their IAC 2016 presentation (available on YouTube), the Lockheed Martin representatives mention studying Phobos and Deimos for their possible water resources, but these do not form part of their mission architecture.
Two of Lockheed Martin’s own fundamental principles are clear from the various presentations:
Regarding the first of these, I can only say that the extra risk involved in going all the way to the surface is small, and the benefit of establishing a safe haven on the surface is large – such a base has access to local resources, does not suffer from orbital decay, and can be reached by other crews even if their rendezvous maneouvres are tens of kilometres off. This is of course all described in Zubrin’s The Case for Mars; so too is the case for not worrying too much about interplanetary “contamination”. But Lockheed Martin themselves expect to see a manned landing on only a later mission following one or more Mars Base Camp orbital missions, leaving open the very plausible scenario that living organisms are not discovered on Mars until a manned surface base has been active for many years and has acquired the ability to drill down to the water table.
As for the second of Lockheed Martin’s principles: orbital rendezvous and docking is a mature technology thanks to decades of LEO experience; surface rendezvous is still more reliable as a guarantor of crew safety; so the effect of this principle is not to increase safety, but to cut off any opportunities to utilise surface resources for refuelling. Given the fact that everyone concerned no doubt has the comparison with Mars Direct at the back of their mind, this effect is presumably not a bug, as the saying goes, but a feature.
In fact the Mars Base Camp architecture fails to incorporate any of our own five principles listed above, earning Lockheed Martin a score of 0 out of 5.
NASA itself has a different strategy (Spaceflight, July 2016, p.252-59). Like Lockheed Martin, it uses solar-electric propulsion for the interplanetary voyage. Notably it envisages manufacturing methane and oxygen propellants on the surface of Mars, but only using them for the return to Mars orbit – a scheme which Zubrin described as Mars Semi-Direct.
While NASA is now very open to commercial activities in low Earth orbit, it does not attempt to describe how the SLS and other vehicles used for Mars could fulfil any economic function, limiting its score here to half a point. The other three principles being altogether absent, NASA’s roadmap earns a score of 1½ out of 5.
The privately proposed Mars settlement ventures, from Robert Zubrin (1990) and Elon Musk (2016) and their collaborators, are therefore well out in front so far as the sustained exploration and settlement of Mars is concerned, even while leaving some room for improvement.
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